JP2005266657A - Optical waveguide, optical waveguide device, and optical information processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical waveguide which allows desired incident light to efficiently impinge thereon and be propagated to a light exit side and be emitted, while having a relatively simple structure and to provide an optical waveguide device and an optical information processing apparatus which use the optical waveguide. <P>SOLUTION: In an optical waveguide 40a, a core structure, comprising first cores 5A, 5B, and 5C having refractive indexes higher than those of the lower clad 11 and the upper clad 12 and second cores 6A, 6B, and 6C which have refractive indexes higher than those of the first cores 5A, 5B, and 5C and partially project from light exit sides of the first cores 5A, 5B, and 5C and are jointed, is jointed to the lower clad 11 and the upper clad 12, and light incidence surfaces 4A, 4B; and 4C of the first cores 5A, 5B, and 5C are arranged facing LEDs 3R, 3G, and 3B; and the light incidence areas of at least light incidence surfaces 4A, 4B, and 4C are larger than light propagation areas of the second cores 6A, 6B, and 6C; and the second cores 6A, 6B, and 6C are extended from a junction area of the first cores 5A, 5B, and 5C toward a light-exiting surface 8. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical information processing apparatus such as an optical waveguide, an optical waveguide apparatus, and a display, which is composed of a joined body of a core and a clad and is suitable for a light source module, optical interconnection, optical communication, and the like.

  Until now, information transmission over a relatively short distance, such as between boards in an electronic device or between chips in a board, has been carried out mainly by electrical signals, but in order to improve the performance of integrated circuits, And high-density signal wiring are required. However, in the electric signal wiring, it is difficult to increase the speed of the electric signal and increase the density of the electric signal wiring due to problems such as signal delay and noise generation due to the time constant of the wiring.

  Optical wiring (optical interconnect cushion) that solves these problems has attracted attention. Optical wiring can be applied to various locations such as between electronic devices, between boards in electronic devices, or between chips in a board. For example, chips are used for transmission of signals over a short distance such as between chips. It is possible to construct an optical transmission and communication system in which an optical waveguide is formed on a substrate on which it is mounted, and a signal modulation laser beam or the like is used as a transmission path.

  On the other hand, it is also known to use an optical waveguide as a light source module of a display. For example, the development of a head mounted display that allows you to enjoy video software, games, computer screens, movies, etc. on your own day screen has been developed. There is a personal display that can be easily felt anywhere (see US Pat. No. 5,467,104).

  Red, green and blue light emitting diodes (LEDs) are used as the light source for this head mounted display, but the LED light is not coherent, has a wide radiation angle, and is condensed to combine the three colors. Is difficult. Therefore, a technique is known in which three types of LED light are combined through an optical waveguide to create uniform white light (Nikkei Electronics 2003.3.31, p127).

  Further, there is an image display device 61 as shown in FIG.

  In the structure of the image display device 61, incident light 79, which is emitted light from the LED (R) 53R, LED (B) 53G, and LED (G) 53G, is a G-reflecting dichroic mirror 52 or an R-reflecting dichroic mirror. After passing through or totally reflecting 55, the light reaches the eyeball 60 through the color liquid crystal panel 50 and the eyepiece lens 56 provided with the convex lens 51 in order.

  Here, the dichroic mirror 52 or 55 has a function of coating a surface of a glass substrate with various dielectric multilayer films and selecting and reflecting a desired specific wavelength. When it is disposed on the optical path with an inclination of 45 ° with respect to the direction, light of a specific wavelength is reflected among light incident on the mirror 52 or 55, but light of other wavelengths is transmitted.

  In driving the image display device 61, the light emitted from the LED (G) 53G is totally reflected by the action of the G reflecting dichroic mirror 52 and transmitted through the R reflecting dichroic mirror 55, and then the color liquid crystal panel. To 50. The light emitted from the LED (R) 53R is totally reflected by the action of the R reflecting dichroic mirror 52 and then guided to the color liquid crystal panel 50. The light emitted from the LED (B) 53B is guided to the color liquid crystal panel 50 after passing through the G-reflecting dichroic mirror 52 and the R-reflecting dichroic mirror 55. In this way, the three primary colors are combined and guided to the color liquid crystal panel 50 (see Patent Document 1 described later).

  Further, there is a virtual retina display 63 which is the image display device shown in FIG.

  In this structure, a single mode monofilament optical fiber or single strand optical fiber 66 is used to couple incident light 79 from a light source such as photon generator 64 to the scanning system. The single monofilament optical fiber 66 has an inlet opening 65 leading to a single core 84 of the fiber 66, and the core 84 extends to the outlet opening 67 by the length of the optical fiber 66. It is.

  For driving the virtual retina display 63, the light from the point light source that is converged by the convex lens 51 and propagates through the core 84 in the optical fiber 66 and is emitted from the exit opening 67 of the optical fiber 66 is another convex lens. 51 is coupled to the horizontal microscanner 68 of the scanning system. Light incident on the horizontal microscanner 68 is totally reflected and directed onto the vertical microscanner 69 and then further totally reflected and scanned on the retina of the user's eye 60 through the optical scanning system 70 and another convex lens 51. (See Patent Document 2 described later).

  Further, there is an optical waveguide as shown in FIG.

  That is, in the optical waveguide 90 shown in FIG. 49A, the core is divided into three types of cores 83R, 83G, and 83B each having a curved inclined surface 59, and these light incident surfaces 54A, 54B, and 54C are respectively provided on the light incident surfaces 54A, 54B, and 54C. LDs (laser diodes) 53R, 53G, and 53B, which are light sources, are disposed (LEDs may be disposed), and the cores 83R and 83B are joined to the core 83G in front of the light emitting surface 58, respectively. The incident light 79 is guided to the exit surface 58 through the light and exits. Here, assuming that the width of the exit surface 58 is fixed to 50 μm, the pitch between adjacent cores is P (μm), and the distance from the entrance surfaces 54A, 54B and 54C to the exit surface 58 is d (mm). FIG. 49B shows the correlation characteristics (excluding loss due to multiplexing) between the length d (mm) from the surfaces 54A, 54B and 54C to the exit surface 58 and the optical loss (dB) due to waveguide propagation. become that way.

  According to this, when the allowable optical loss of the optical waveguide 90 is set to 2 dB or less indicated by a broken line, for example, under the condition a in which the pitch P between adjacent cores is set to 200 μm, the incident surfaces 54A, 54B and 54C are exited from the exit surface. The length d up to 58 is required to be about 6 mm or more. Similarly, if the pitch P between adjacent cores is set to 400 μm and 600 μm, the length d from the entrance surfaces 54A, 54B and 54C to the exit surface 135 is about 20 mm or more. About 60 mm or more is required.

  From this result, even if the pitch P between the adjacent core portions is narrowed and the inclination angle of the curved inclined surfaces 59 of the cores 83R and 83B is moderated, the above-mentioned length d is set to suppress the optical loss to 2 dB or less. It is necessary to increase it to about 6 mm or more. This is because the light leakage from the cores 83R, 83G, 83B and the common core 57 to the lower cladding 62 cannot be sufficiently suppressed because the inclination angle of the curved inclined surfaces 59 of the cores 83R and 83B is still steep. This is because if the length d is not increased, the inclined surface of the curved inclined surface 59 cannot be made gentle to reduce the light leakage (see Patent Document 3 described later).

JP-A-8-76078 (page 4, right column, line 37 to page 5, left column, line 16, line 6)

Japanese Patent Publication No. 11-505627 (page 21, line 24 to page 24, line 17, FIG. 9)

Japanese Unexamined Patent Publication No. 2003-386686 (page 11, line 5 to page 11, line 27, FIG. 15)

  For example, in the conventional example shown in FIG. 47, a convex lens or the like (not shown) is used to make incident light 79, which is light emitted from each LED, incident on each dichroic mirror. This is because LED light tends to diffuse unlike laser light and the like, and it is necessary to converge the emitted light in order to efficiently make the emitted light from the light source enter each dichroic mirror.

  The same applies to the conventional example shown in FIG. 48. When light is incident on the optical fiber 66, the horizontal micro scanner, the eyeball 60, and the like, the light is converged by using a plurality of convex lenses 51 to increase the incident efficiency. ing.

  In addition, in the conventional example shown in FIG. 49, since the cross-sectional area that is the light propagation area of each core is relatively small, in order to make incident light 79 from each LED efficiently incident on each incident surface, it is not shown. Arranges a lens etc. between each LED and each entrance plane.

  In the above conventional example, since the light incident area of the light incident object is smaller than the diffusion region of the light emitted from each LED, the light source that collects the light emitted from each LED using a mirror, a lens, or the like And incident. However, this method increases the size of the light source device, increases the number of mounted parts such as lenses and mirrors, makes the structure complicated, and increases manufacturing costs. In addition, there is a problem that it is necessary to mount each component such as a mirror or a lens with high accuracy in order to collect light.

  The present invention has been made in view of the situation as described above, and the object thereof is to make incident light efficiently incident and propagate to the light emitting side and output, while the structure is relatively simple. An optical waveguide that can be used, an optical waveguide device using the optical waveguide, and an optical information processing apparatus.

  That is, according to the present invention, a first core portion having a refractive index higher than that of the cladding and a refractive index higher than that of the first core portion, and a part of the first core portion is protruded and joined from one end face side. A core composed of two core parts is joined to the clad, the other end face of the first core part is arranged to face the light emitting element, and at least the light incident area of the other end face is the light of the second core part. The present invention relates to an optical waveguide having a larger propagation area and the second core portion extending from the junction region with respect to the first core portion to the light emitting side.

  In the present invention, a core having a refractive index higher than that of the clad is joined to the clad, the core has a continuous structure of a first core portion and a second core portion, and an end surface of the first core portion is a light emitting element. The light incident area of at least the end face is larger than the light propagation area of the second core portion, and the second core portion is extended from the continuous region with respect to the first core portion to the light emitting side. It relates to the optical waveguide.

  The present invention also provides an optical waveguide device comprising the optical waveguide and a light emitting element.

  The present invention also provides an optical information processing apparatus in which the optical waveguide device is disposed on an optical path.

  According to the optical waveguide of the present invention, the end surface of the first core portion having a light incident area larger than the light propagation area of the second core portion for propagating incident light to the light exit surface is opposed to the light emitting element. Therefore, the emitted light from the light emitting element can be incident into the first core portion relatively efficiently, and the amount of incident light can be increased, and the concentration between the light emitting element and the first core portion can be increased. Optical means can be omitted, and a relatively small and simple optical waveguide structure can be obtained.

  Furthermore, since the refractive index of the second core part is higher than that of the first core part, the light in the first core part can easily enter the second core part. In addition, since the second core part is joined in a state where a part projects from one end face side of the first core part, the joining area between the first core part and the second core part is relatively large. Thus, the light in the first core part is more likely to enter the second core part.

  According to another optical waveguide of the present invention, the end face of the first core portion having a light incident area larger than the light propagation area of the second core portion for propagating incident light to the light exit surface is a light emitting element. Since the light emitted from the light emitting element is incident on the first core part relatively efficiently, the amount of incident light can be increased, and between the light emitting element and the first core part. The light condensing means can be omitted, and the optical waveguide can be made relatively small and simple. Further, since the core has a continuous structure of the first core portion and the second core portion, the core can be manufactured integrally, and the manufacturing process can be simplified.

  In addition, an optical waveguide device including the optical waveguide and a light emitting element and an optical information processing device in which the optical waveguide device is disposed on the optical path are effectively configured with the above-described features of the optical waveguide. Can do.

  In the present invention, in order to efficiently propagate the light propagating in the first core part into the second core part, the light propagation area of the second core part gradually increases or decreases in the light propagation direction. It is desirable.

  In this case, it is desirable that the light propagation area of the first core portion gradually decreases in the light propagation direction.

  Further, in order to increase the degree of freedom of arrangement of the light emitting elements and the amount of light incident on the first core portion, the other end surface of the first core portion forms an inclined surface, and the inclined surface is separated from the light emitting element. It is desirable that the light is reflected and guided into the first core portion.

  In addition, in order to multiplex incident light incident from a plurality of the light emitting elements, a plurality of the cores are provided corresponding to the light emitting elements, and the second core portions of these cores join to the light emitting side. It is desirable to extend.

  In this case, in order to increase the arrangement of the cores, the types of the light emitting elements, and the degree of freedom of the arrangement, the plurality of cores includes a first core and a second core, and the merging positions of these cores It is preferable that a means for selectively transmitting or reflecting light of a specific wavelength is arranged, and light propagated from the plurality of cores is combined through this means.

  In this case, multiplexing for selectively transmitting or reflecting the light guided from the second core part of the third core and the light guided through the common core part from the joining position is combined. It is desirable that the means is disposed at a joining position between the third core and the common core portion.

  In addition, in order to increase the arrangement of the cores, the types of the light emitting elements, and the degree of freedom of the arrangement, a plurality of the first core parts are provided, and these first core parts merge to extend to the light emitting side. It is desirable that the core is formed by joining or continuously connecting the second core portion at a position on the light emission side from the joining position.

  In this case, a means for selectively transmitting or reflecting light of a specific wavelength is arranged at the joining position of the plurality of first core parts, and the light propagated from the plurality of first core parts via this means. Are preferably combined.

  And in this case, there is a multiplexing means for selectively transmitting or reflecting the light guided from the third first core part and the light guided through the common core part from the joining position. It is desirable that the third core portion and the common core portion are disposed at a merging position.

  Further, a step may be present between the first core portion and the second core portion at a position where the first core portion and the second core portion are connected.

  In this case, it is preferable that the center line of the second core part coincides with the center line of the first core part in order to make the incident light quantity incident on the first core part more incident on the second core part. .

  The bottom surface or top surface of the second core portion may be on the same plane as the bottom surface or top surface of the first core portion.

  In order to make the emitted light from the light emitting element enter the first core portion more efficiently, it is desirable that a condenser lens is disposed between the light emitting element and the first core portion.

  Further, light from a light source such as a light emitting diode or laser light can be collected by the optical waveguide.

  The core and the clad may be formed of a photocurable resin. This is because it is easy to pattern the core corresponding to the exposure pattern by irradiation with light (particularly ultraviolet rays), and it is also advantageous as a constituent material of the clad. Examples of such a photocurable resin include high molecular organic materials such as oxetane resins described in JP 2000-356720 A. Such a high molecular weight organic material preferably transmits 90% or more of possible visible light having a wavelength of 390 nm or less. In addition to the photocurable resin, an inorganic material may be used for the core material or the clad material.

  In addition, as the optical waveguide material, for example, an oxetane resin made of an oxetane compound having an oxetane ring or a polysilane made of an oxirane compound having an oxirane ring can be used. A composition containing a cationic polymerization initiator capable of initiating polymerization by a chain reaction is preferably used.

  In the present invention, the signal light emitted from the optical waveguide is scanned and projected by the scanning means, and the light is incident on the light receiving element (optical wiring, photodetector, etc.) of the next stage circuit. Thus, it can be effectively used for an optical information processing apparatus such as optical communication configured as described above.

  Next, a preferred embodiment of the present invention will be specifically described with reference to the drawings.

First Embodiment An optical waveguide device according to this embodiment will be described with reference to FIGS.

  First, as shown in the plan view of FIG. 1A, in this optical waveguide 40a, a linear second core 6B as a second core portion, second cores 6A and 6C having a curved inclined surface 9, The linear first cores 5A, 5B, and 5C, which are the first core portions, are formed in combination as three cores. The back surface is connected and fixed to the electrode 1A on the substrate 10 on the side of the light incident surfaces 4A, 4B and 4C which are the end surfaces of the first cores 5A, 5B and 5C, and the metal wire 2 is connected to the electrode 1B on the substrate 10 The red LED (R) 3R, the green LED (G) 3G, and the blue LED (B) 53B, which are the light emitting elements, are arranged to face each other. In addition, the second core 6A joined to the first core 5A in the joining region and the second core 6C joined to the first core 5C in the joining region at the front of the light emitting surface 8 are joined to the first core 5B and the joining region. Combined with the joined second core 6B to form the common core 7, combine the propagation light from each first core, guide the combined light of the incident light 29 to the emission surface 8 through the common core 7, and output as the output light 30 It has a structure to do.

  Further, as shown in the cross-sectional view along the line AA ′ in FIG. 1A, in this optical waveguide 40a, a lower cladding having a predetermined shape and thickness is formed at a predetermined position on the silicon substrate 10 having a predetermined shape and thickness. 11, a first core 5B, a second core 6B, and an upper clad 12 having a predetermined shape and thickness are sequentially formed on the lower clad 11. The light incident side of the second core 6B protrudes toward the LED 3G to form a buried portion 13 in the first core 5B up to the position of the central portion of the cross section of the first core 5B. The first cores 5A and 5C and the second cores 6A and 6C are formed in the same manner.

  Further, as shown in FIG. 2A (a cross-sectional view taken along the line BB ′ in FIG. 1A), first cores 5A, 5B, and 5C having a rectangular cross section are provided on the lower clad 11 at predetermined intervals. The upper clad 12 is formed so as to cover them. Further, as shown in FIG. 2B (a cross-sectional view taken along the line CC ′ in FIG. 1A), the second cores 6A, 6B having a rectangular cross section in the center at predetermined intervals on the lower cladding 11 and First cores 5A, 5B, and 5C having a rectangular cross section in which 6C is embedded are provided, and an upper clad 12 is formed so as to cover them. Further, as shown in FIG. 2C (cross-sectional view taken along the line DD ′ in FIG. 1A), the second cores 6A and 6B having a rectangular cross section in the upper clad 12 on the lower clad 11 at a predetermined interval. And 6C are provided.

For example, the cross section of each of the first cores 5A, 5B, and 5C is 50 × 50 μm, the cross section of the cores of the second cores 6A, 6B, and 6C is 10 × 10 μm, and the second cores 6A, 6B, and 6C. The cross sections of the first cores 5A, 5B, and 5C are larger than those of the first cores 5A, 5B, and 5C. Further, the refractive index of the lower cladding 11 is 1.505, the relative refractive index difference with the first cores 5A, 5B, and 5C is 0.2%, and the second refractive index is larger than those of the first cores. The relative refractive index difference with the cores 6A, 6B and 6C is 0.3%. Overlapping length L _{1 of} the first cores 5A, 5B and 5C and the second cores 6A, 6B and 6C (the length of the embedded portion 13 in which the second cores 6A, 6B and 6C project to form a double core structure) ) Is 1000 μm.

  Further, the center lines of the second cores 6A, 6B and 6C (or the center axis in the length direction: the same applies hereinafter) are arranged so as to coincide with the center lines of the first cores 5A, 5B and 5C. In addition, light emitted from each LED arranged to face the first cores 5A, 5B, and 5C enters the first cores 5A, 5B, and 5C, and then enters the second cores 6A, 6B, and 6C. For example, each of the second cores having a gently curved inclined surface 9 having a radius of curvature of 30 mm is guided to the common core 7 which is a confluence of these, and the light is emitted after the lights merge in the common core 7. The light is emitted as 10 μm spot light 30 from the surface 8.

  According to the present embodiment, the first cores 5A, 5B and 5C having a light incident area larger than the light propagation area of the second cores 6A, 6B and 6C for propagating the incident light 29 to the light exit surface 8 Since the incident surfaces 4A, 4B, and 4C are arranged to face the LEDs 3R, 3G, and 3B, the light emitted from the LEDs 3R, 3G, and 3B is incident on the first cores 5A, 5B, and 5C relatively efficiently. The amount of incident light can be increased, and a lens or the like as a condensing means between the LEDs 3R, 3G, and 3B and the first cores 5A, 5B, and 5C can be omitted, and the optical waveguide 40a has a relatively simple structure. It can be.

  Furthermore, since the refractive indexes of the second cores 6A, 6B, and 6C are higher than those of the first cores 5A, 5B, and 5C, the light in the first cores 5A, 5B, and 5C is incident on the second cores 6A, 6B, and 6C. It becomes easy to do and it becomes difficult to leak outside. In addition, since the second cores 6A, 6B, and 6C are joined in a state in which a part protrudes from the emission side of the first cores 5A, 5B, and 5C, the first cores 5A, 5B, and 5C The joint area with the second cores 6A, 6B, and 6C is relatively large, and the light in the first cores 5A, 5B, and 5C is more likely to enter the second cores 6A, 6B, and 6C.

  Further, for example, generally, when an optical waveguide is used, there is a merit that a light source device that can easily couple light of each LED can be reduced in size. However, since the size of the light emitting surface of a general LED is large, for example, when a point light source having a size of about 10 μm is to be realized using a core having a cross section of 10 μm square, the optical relationship between the LED and the core is reduced. The coupling efficiency becomes worse.

  Therefore, by using the structure in which the cross section of the first cores 5A, 5B, and 5C at the portions facing the respective LEDs 3R, 3G, and 3B is enlarged as described above, and the common core 7 having a small cross section is arranged on the emission surface 8. The optical coupling efficiency between the LEDs 3R, 3G, and 3B and the first cores 5A, 5B, and 5C is improved, and a point light source with a small emission light size can be realized.

  In this case, since the center lines of the first core and the second core coincide with each other, the connection loss at the connection portion (or stepped portion 42 described later) between the first core and the second core is the highest. (Same in the following example).

  In addition, since the light basically has a property of being guided through a region having a high refractive index, in the above structure, the light from each LED is incident on the first cores 5A, 5B and 5C with high coupling efficiency. Later, the light guides efficiently through the second cores 6A, 6B, and 6C having a higher refractive index than the first cores 5A, 5B, and 5C, and reaches the exit surface 8. As a result, on the emission surface 8, emission light having a small size and high light intensity can be obtained. In addition, since the first cores 5A, 5B, and 5C have a large cross-section at the coupling portion with the LED, a wide positional deviation tolerance with the LED can be obtained, so that alignment during mounting is relatively easy.

  The optical waveguide and the device according to the present embodiment are suitable as a light source for an image display device (display) as shown in FIGS. 47 and 48, for example.

  Next, a manufacturing method of the optical waveguide 40a will be described with reference to FIGS.

  First, as shown in FIG. 3A, after a substrate 10 having a predetermined shape and thickness is arranged, a lower clad having a predetermined shape and thickness is formed at a predetermined position on the substrate 10 as shown in FIG. 3B. Part 11a is formed.

  Next, as shown in FIG. 3C, a core portion 5a having a predetermined shape and thickness is formed at a predetermined position on the lower clad portion 11a.

  Next, as shown in FIG. 3 (d), a lower clad portion 11b having a predetermined shape is formed in a portion other than the core portion 5a on the lower clad portion 11a with the same thickness as the core portion 5a. The lower cladding portions 11a and 11b are integrated to form the lower cladding 11, and a boundary line between the lower cladding portion 11a and the lower cladding portion 11b is represented by a broken line.

  Next, as shown in FIG. 3E, a second core 6B having a predetermined shape and thickness is formed from the lower clad 11 to the core portion 5a.

  Next, as shown in FIG. 3F, a core portion 5b having a predetermined shape and thickness is formed on the core portion 5a so as to embed a part of the second core 6B. The core portions 5a and 5b are integrated to form the first core 5B, and the boundary line between the core portion 5a and the core portion 5b is indicated by a broken line. A portion of the second core 6B embedded in the first core 5B is referred to as an embedded portion 13. The core forming process is the same when the second core portions 6A and 6C are partially embedded in the first core portions 5A and 5C, and the description thereof is omitted.

  Next, as shown in FIG. 4G, an upper clad 12 having a predetermined shape and thickness is formed so as to cover the second core 6B and the first core 5B.

  Next, as shown in FIG. 4 (h), the portions on the light incident side of the core 5B and the clads 11 and 12 are removed, and on the substrate 10 on the light incident end face side of the first core 5B in this removal region, Each LED 3G, 3R, 3B is mounted via the electrode 1A, and the optical waveguide 40a is produced. Note that the optical waveguide may be peeled off from the substrate 10 in the state of FIG. 4G and bonded and fixed on another substrate 10 in the same manner as in the process of FIG. 32 described later (hereinafter the same).

  Next, with reference to FIG. 5 to FIG. 6 (a cross-sectional view corresponding to FIG. 2B orthogonal to the light propagation direction), a method of manufacturing the optical waveguide 40a and the device will be described.

  As shown in FIG. 5A, after the substrate 10 having the predetermined shape and thickness is arranged, the lower clad portion 11a having the predetermined shape and thickness is formed at a predetermined position on the substrate 10 as shown in FIG. 5B. Form.

  Next, as shown in FIG. 5C, after the core material 25 having a predetermined shape and thickness is formed on the lower clad portion 11a, the core 25 material is processed as shown in FIG. Three core portions 5a having a predetermined shape are formed at predetermined locations on the lower clad portion 11a.

  Next, as shown in FIG. 5E, the lower cladding portion 11b is formed between the core portions 5a formed on the lower cladding portion 11a with the same thickness as the core portion 5a. The lower cladding portions 11a and 11b are integrated to form the lower cladding 11, and a boundary line between the lower cladding portion 11a and the lower cladding portion 11b is represented by a broken line.

  Next, as shown in FIG. 5F, a core material 28 having a predetermined shape and thickness is formed on the lower cladding portion 11b and the core portion 5a.

  Next, as shown in FIG. 6G, the core material 28 is processed to form second cores 6A, 6B, and 6C having rectangular cross sections on the three core portions 5a. The center lines of the second cores 6A, 6B and 6C are formed so as to coincide with the center lines of the first cores 5A, 5B and 5C.

  Next, as shown in FIG. 6 (h), the second cores 6A, 6B, and 6C are embedded in the core portion 5a, the lower cladding portion 11b, and the second cores 6A, 6B, and 6C, and the predetermined shape and A thick core material 25 is formed.

  Next, as shown in FIG. 6 (i), the core material 25 is processed to form the core portions 5b at three locations. The core portions 5a and 5b are integrated to form first cores 5A, 5B, and 5C having a rectangular cross section, and a boundary line between the core portion 5a and the core portion 5b is represented by a broken line.

  Next, an upper clad 12 having a predetermined shape and thickness is formed so as to cover the respective core portions 5b of the first cores 5A, 5B, and 5C, and light incident on the first cores 5A, 5B, and 5C. Each LED is mounted on the substrate 10 on the end face side to produce the optical waveguide 40a.

Second Embodiment In the present embodiment, as shown in the plan view of FIG. 7A and the cross-sectional view of FIG. 7B, the light incidence of the first cores 5A, 5B, and 5C in the optical waveguide 40b. The surfaces 4A, 4B, and 4C are each provided with an inclined surface 14 that is processed at an angle of 45 °, and the LEDs 3R, 3G, and 3B are disposed in a recess 15 that is formed by processing the substrate 10 below the inclined surface 14. Except for the arrangement, the second embodiment is the same as the first embodiment.

  In the present embodiment, as shown in FIG. 7B, the incident light 29 radiated from the LEDs 3R, 3G, and 3B is incident from the lower surface of the lower clad 11 made of a light-transmitting material. The light is totally reflected by the inclined surface 14 of the first core 5B, enters the first core 5B, propagates through the first core 5B, further propagates through the second core 6B, and then exits from the exit surface 8 as a 10 μm spot light source. .

  According to the present embodiment, in general, many inexpensive LEDs have a structure in which a light emitting surface is a surface (upper surface), and emitted light is emitted upward. For this purpose, by making the incident surface of each first core into the inclined surface 14, the emitted light emitted upward is reflected in the lateral direction (light propagation direction) of each first core and into each first core. And can be guided efficiently.

  Further, in the arrangement of the LEDs, when the inclined surface 14 is turned upside down, the LEDs may be arranged on the upper part.

  In addition, in this embodiment, the same operations and effects as described in the first embodiment are obtained.

Third Embodiment In the present embodiment, as shown in the plan view of FIG. 8A and the cross-sectional view of FIG. 8B, each embedded in the first cores 5A, 5B and 5C of the optical waveguide 40c. In the portion 13, the widths of the second cores 6A, 6B, and 6C gradually increase from the incident surfaces 4A, 4B, and 4C of the first cores 5A, 5B, and 5C toward the exit surface (or each The second embodiment is the same as the second embodiment except that the width gradually decreases toward the incident surface.

In the present embodiment, as shown in FIG. 8A, the widths of the first cores 5A, 5B, and 5C are constant, but the widths of the second cores 6A, 6B, and 6C in the embedded portion 13 are It has a planar shape that gradually increases linearly from 2 μm to 10 μm over a distance of 1000 μm (the above-mentioned L ₁ ) from the front end portion 41 of the embedded portion 13 to the end face side of the first cores 5A, 5B, and 5C. Yes.

  Further, as shown in FIG. 9A (a cross-sectional view taken along line BB ′ in FIG. 8A), first cores 5A, 5B, and 5C having a rectangular cross section are provided on the lower clad 11 at predetermined intervals. The upper clad 12 is formed so as to cover them. Further, as shown in FIG. 9B (a cross-sectional view taken along the line CC ′ in FIG. 8A), the second core 6A having a rectangular cross section with a predetermined width on the lower clad 11 and a narrow central section. , 6B and 6C are respectively embedded in the first cores 5A, 5B and 5C having a rectangular cross section, and an upper clad 12 is formed so as to cover them. Further, as shown in FIG. 9C (cross-sectional view taken along the line DD ′ in FIG. 8A), the second cores 6A and 6B having a rectangular cross section in the upper clad 12 on the lower clad 11 at a predetermined interval. And 6C are provided. The center lines of the second cores 6A, 6B and 6C are arranged so as to coincide with the center lines of the first cores 5A, 5B and 5C.

  With this configuration, as shown in FIG. 10, in the embedded portion 13 in the first core 5A, the width of the second core 6A gradually decreases toward the incident surface of the first core 5A. Therefore, the optical coupling efficiency between the first core 5A and the second core 6A can be improved.

  In other words, the shape of the optical mode 31a of the second core 6A gradually increases toward the vicinity of the tip 41, which is the finest detail of the second core 6A, and the shape of the optical mode 31b of the first core 5A having a larger core width. Since the mode shapes approach each other, the shapes of the modes 31a and 31b easily match in the vicinity of the tip 41 of the second core 6A, and the optical coupling efficiency can be improved.

  In addition, in the present embodiment, the same operations and effects as described in the second embodiment described above can be obtained.

Fourth Embodiment In the present embodiment, as shown in the plan view of FIG. 11A and the cross-sectional view of FIG. 11B, each embedded in the first cores 5A, 5B, and 5C of the optical waveguide 40d. In the vicinity of the portion 13, the first cores 5A, 5B, and 5C have the width of the third core described above except that the width is gradually narrowed by the linear inclined surface 16 from the incident surfaces 4A, 4B, and 4C toward the emission side. This is the same as the embodiment.

  In the present embodiment, the widths of the first cores 5A, 5B, and 5C are 50 μm to 14 μm wide due to the linear inclined surface 16 extending over a length of 1500 μm from the middle of the first core to the emission side end surface. The widths of the second cores 6A, 6B and 6C are linear from 2 μm to 10 μm over 1000 μm from the front end 41 of the embedded portion 13 to the end face side of the first cores 5A, 5B and 5C. It has become wide.

  Also, as shown in FIG. 12A (a cross-sectional view taken along line BB ′ in FIG. 11A), first cores 5A, 5B, and 5C having a rectangular cross section are provided on the lower clad 11 at predetermined intervals. The upper clad 12 is formed so as to cover them. Further, as shown in FIG. 12B (a cross-sectional view taken along the line CC ′ in FIG. 11A), the second core 6A having a rectangular cross section with a narrow width at the center on the lower clad 11 at a predetermined interval. , 6B and 6C, each having a narrow cross-sectional first core 5A, 5B and 5C, and an upper clad 12 is formed so as to cover them. Further, as shown in FIG. 12C (a cross-sectional view taken along the line DD ′ in FIG. 11A), the second cores 6A and 6B having a rectangular cross section in the upper clad 12 on the lower clad 11 at a predetermined interval. And 6C are provided, and an upper clad 12 is formed so as to cover them. The center lines of the second cores 6A, 6B and 6C are arranged so as to overlap the center lines of the first cores 5A, 5B and 5C.

  As shown in FIG. 13, in the embedded portion 13 of the first core 5A, the shape of the second core 6A has a structure in which the width gradually decreases toward the incident surface of the first core 5A. The optical coupling efficiency between the first core 5A and the second core 6A can be improved by making the shape of 5A have a structure in which the width gradually decreases toward the emission side end face.

  That is, the shape of the optical mode 31a of the second core 6A gradually increases toward the vicinity of the tip 41, which is the finest detail of the second core 6A, and the light of the first core 5A represented by a thick line with a larger core width. Since the mode shape approaches the shape of the mode 31b, the mode shapes are easily matched and the optical coupling efficiency can be improved.

  In addition, the shape of the optical mode 31b represented by a thick line gradually decreases toward the vicinity of the emission side end of the first core 5A, and the mode shape is changed to the shape of the optical mode 31a of the second core 6A having a smaller core width. Therefore, the mode shapes are more easily matched therewith, and the optical coupling efficiency can be improved. Therefore, the optical coupling efficiency of the first core with respect to the second core is further improved.

  In addition, in this embodiment, the same operations and effects as described in the third embodiment are obtained.

Fifth Embodiment In the present embodiment, as shown in the plan view of FIG. 14A and the cross-sectional view of FIG. 14B, each embedded in the first cores 5A, 5B, and 5C of the optical waveguide 40e. In the portion 13, the second cores 6A, 6B, and 6C have the widths of the second cores described above except that the widths of the second cores 6A, 6B, and 6C gradually increase toward the incident side of the first cores 5A, 5B, and 5C. This is the same as the embodiment.

  In the present embodiment, the first cores 5A, 5B and 5C have a constant width of 50 μm, but the second cores 6A, 6B and 6C are connected to the first cores 5A and 5B from the tip 41 of the embedded portion 13. And a planar shape in which the width linearly narrows from 25 μm to 10 μm over 1000 μm up to the emission side of 5C.

  Further, as shown in FIG. 15A (a cross-sectional view taken along line BB ′ in FIG. 14A), first cores 5A, 5B, and 5C having a rectangular cross section are provided on the lower clad 11 at predetermined intervals. The upper clad 12 is formed so as to cover them. Further, as shown in FIG. 15B (a cross-sectional view taken along the line CC ′ in FIG. 14A), the second core 6A having a rectangular section with a wide width at the center at a predetermined interval on the lower clad 11. , 6B and 6C are provided with first cores 5A, 5B and 5C having a rectangular cross section, and an upper clad 12 is formed so as to cover them. Further, as shown in FIG. 15C (cross-sectional view taken along the line DD ′ in FIG. 14A), the second cores 6A and 6B having a rectangular cross section in the upper clad 12 on the lower clad 11 at a predetermined interval. And 6C are provided, and an upper clad 12 is formed so as to cover them. The center lines of the second cores 6A, 6B and 6C are arranged so as to coincide with the center lines of the first cores 5A, 5B and 5C.

  As shown in FIG. 16, in the embedded portion 13 of the first core 5A, the shape of the second core 6A is a structure that gradually increases in width toward the incident surface of the first core 5A, so that the first core The optical coupling efficiency between 5A and the second core 6A can be improved.

  That is, the shape of the optical mode 31a of the second core 6A gradually increases toward the vicinity of the tip 41, which is the thickest part of the second core 6A, and the optical mode 31b of the first core 5A having a larger core width. Since the mode shape approaches the shape, the mode shapes can easily be matched, and the optical coupling efficiency can be improved.

  In addition, in the present embodiment, the same operations and effects as described in the second embodiment described above can be obtained.

Sixth Embodiment In the present embodiment, as shown in the plan view of FIG. 17A and the cross-sectional view of FIG. 17B, each embedded in the first cores 5A, 5B and 5C of the optical waveguide 40f. In the portion 13, the widths of the second cores 6A, 6B, and 6C are gradually narrowed by the linear inclined surface 17 from the incident surfaces 4A, 4B, and 4C toward the exit side of the first cores 5A, 5B, and 5C. The fifth embodiment described above except that the widths of the first cores 5A, 5B and 5C are gradually narrowed by the linear inclined surface 16 from the incident surfaces 4A, 4B and 4C toward the exit side. It is the same.

  In the present embodiment, the widths of the second cores 6A, 6B, and 6C are narrowed from 25 μm to 10 μm over 1000 μm from the distal end portion 41 of the embedded portion 13 to the emission side of the first cores 5A, 5B, and 5C. Has a planar shape. Further, the width of the first cores 5A, 5B, and 5C is a plane that narrows from 50 μm to 14 μm over 1500 μm from the vicinity of the front end portion 41 of the embedded portion 13 to the emission side end portions of the first cores 5A, 5B, and 5C. It has a shape.

  Further, as shown in FIG. 18A (a cross-sectional view taken along the line BB ′ in FIG. 17A), first cores 5A, 5B, and 5C having a rectangular cross section are provided on the lower clad 11 at predetermined intervals. The upper clad 12 is formed so as to cover them. Further, as shown in FIG. 18B (a cross-sectional view taken along the line CC ′ in FIG. 17A), the second core 6A having a rectangular section with a wide width at the center at a predetermined interval on the lower clad 11. , 6B and 6C, each having a narrow cross-sectional rectangular first core 5A, 5B and 5C, and an upper clad 12 is formed so as to cover them. Further, as shown in FIG. 18C (cross-sectional view taken along the line DD ′ in FIG. 17A), the second cores 6A and 6B having a rectangular cross section in the upper clad 12 on the lower clad 11 at a predetermined interval. And 6C are provided, and an upper clad 12 is formed so as to cover them. The center lines of the second cores 6A, 6B and 6C are arranged so as to coincide with the center lines of the first cores 5A, 5B and 5C.

  As shown in FIG. 19, in the embedded portion 13 of the first core 5A, the shape of the second core 6A is gradually increased toward the incident surface of the first core 5A, and the shape of the first core 5A By adopting a structure in which the width gradually increases toward the incident surface of the first core 5A, the optical coupling efficiency between the first core 5A and the second core 6A can be improved.

  That is, the shape of the optical mode 31a of the second core 6A gradually increases toward the vicinity of the tip 41, which is the thickest part of the second core 6A, and the optical mode 31b of the first core 5A having a larger core width. Since the mode shape approaches the shape, the mode shapes can easily be matched, and the optical coupling efficiency can be improved.

  In addition, the shape of the optical mode 31b indicated by a thick line gradually decreases toward the most detailed portion of the first core 5A, and the mode shape approaches the shape of the optical mode 31a of the second core 6A having a smaller core width. As a result, the mode shapes are more easily matched, and the optical coupling efficiency can be further improved.

  In addition, in this embodiment, the same operations and effects as described in the fifth embodiment are obtained.

Seventh Embodiment In the present embodiment, as shown in the plan view of FIG. 20A and the cross-sectional view of FIG. 20B, light is incident from each of the light incident surfaces 4A, 4B, and 4C in the optical waveguide 40g. The cores 33A, 33B, and 33C are integrated into a continuous structure up to the exit surface 8, and the widths of the cores 33A, 33B, and 33C are reduced so that the light transmission areas of the cores 33A, 33B, and 33C are reduced in the middle. Except for providing each of the step portions 42 in the thickness direction, it is the same as the first embodiment described above.

  Each core according to the present embodiment includes a core 33A including a first core portion 5A ′ and a second core portion 6A ′ having the same refractive index, and a first core portion 5B ′ and a second core portion having the same refractive index. It is formed as a core 33B composed of 6 ′ and a core 33C composed of a first core portion 5C ′ and a second core portion 6C ′ having the same refractive index.

  Further, the light transmission area of the cores 33A, 33B and 33C facing the respective incident surfaces 4A, 4B and 4C corresponding to the respective LEDs 3R, 3G and 3B is made relatively larger than that of the opposite exit surface 8, Cores 33A, 33B and 33C (that is, 6A ′, 6B ′, 6C ′) are connected to the first portions 5A ′, 5B ′ and 5C ′ and the second portions 6A ′, 6B ′ and 6C ′. ) To form a stepped portion 42 with a small light transmission area.

  The light transmission areas of the first portions 5A ′, 5B ′, and 5C ′ corresponding to the LEDs 3R, 3G, and 3B are 50 × 50 μm, and the second portions 6A ′, 6B ′ on the emission surface 8 on the opposite side. And 6C ′ has a light transmission area of 10 × 10 μm. The refractive index of the lower clad 11 is 1.505, and the relative refractive index difference of each core with respect to this clad is 0.3%. The light transmission cross-sectional area of each core is 50 × 50 μm from the incident surfaces 4A, 4B and 4C of the first portions 5A ′, 5B ′ and 5C ′ to 2000 μm.

  Further, as shown in FIG. 21A (a cross-sectional view taken along line CC ′ in FIG. 20A), first core portions 5A ′, 5B ′, and 5C having a rectangular cross section on the lower clad 11 at a predetermined interval. 'Is provided, and the upper clad 12 is formed so as to cover them. Further, as shown in FIG. 21C (a cross-sectional view taken along the line DD ′ in FIG. 20A), the second core portion 6A ′ having a rectangular cross section in the upper clad 12 on the lower clad 11 at a predetermined interval. , 6B ′ and 6C ′, and the upper clad 12 is formed so as to cover them. The center lines of the second core portions 6A ', 6B' and 6C 'are arranged so as to coincide with the center lines of the first portions 5A', 5B 'and 5C'.

  Next, with reference to FIGS. 22 to 23, a method for manufacturing the optical waveguide 40g and the device thereof will be described.

  First, as shown in FIG. 22A, after a substrate 10 having a predetermined shape and thickness is disposed, a lower clad having a predetermined shape and thickness is formed at a predetermined position on the substrate 10 as shown in FIG. 22B. After forming the portion 11a and forming the core portion 5a having a predetermined shape and thickness at a predetermined location on the lower clad portion 11a as shown in FIG. 22C, as shown in FIG. A lower clad portion 11b having a predetermined shape is formed at a portion other than the core portion 5a on the lower clad portion 11a with the same thickness as the core portion 5a. The lower cladding portions 11a and 11b are integrated to form the lower cladding 11, and a boundary line between the lower cladding portion 11a and the lower cladding portion 11b is represented by a broken line.

  Next, as shown in FIG. 22E, a second portion 6B 'having a predetermined shape and thickness is formed from the lower clad 11 to the core portion 5a. The second portion 6B 'and the core portion 5a are integrated, and the boundary line between the second portion 6B' and the core portion 5a is represented by a broken line.

  Next, as shown in FIG. 22F, a core portion 5b having a predetermined shape and thickness is formed on the core portion 5a so as to embed a part of the second portion 6B '. The core portions 5a and 5b are integrated to form the first portion 5B ', and the core portions 5a and 5b and the second portion 6B' are integrated to form the core 33B. A boundary line between the second portion 6B 'and the core portion 5b is represented by a broken line.

  Next, as shown in FIG. 23G, the upper clad 12 having a predetermined shape and thickness is formed so as to cover the second portion 6B 'and the core portion 5b.

  Next, as shown in FIG. 23 (h), a part of the light incident side of the core 33B is removed, and the LED (G) 3G is formed on the substrate 10 on the light incident end face side of the core 33B via the electrode 1A. An optical waveguide 40g is manufactured by arranging

  According to the present embodiment, since the cores 33A, 33B, and 33C can be integrally manufactured, the optical waveguide 40g can be easily manufactured using the same material.

  In addition, in this embodiment, the same operations and effects as described in the first embodiment are obtained.

Eighth Embodiment In the present embodiment, as shown in the plan view of FIG. 24A and the cross-sectional view of FIG. 24B, in the optical waveguide 40h, the first core portions 5A ′, 5B ′ and 5C. The light incident surfaces 4A, 4B, and 4C are respectively provided with inclined surfaces 14 that are processed at an angle of 45 °, and in the recesses 15 that are formed by processing the substrate 10 below the inclined surfaces 14, each LED 3R, The third embodiment is the same as the seventh embodiment except that 3G and 3B are arranged.

  In the present embodiment, as shown in FIG. 24B, the incident light 29 radiated from the LEDs 3R, 3G, and 3B is incident from the lower surface of the lower clad 11 made of a light transmissive material. After being totally reflected by the inclined surface 14 of the first core portion 5B ′ and entering the first core portion 5B ′, propagating through this, and further propagating through the second core portion 6B ′, 10 μm from the exit surface 8 It is emitted as a spot light source.

  According to the present embodiment, in general, many inexpensive LEDs have a structure in which a light emitting surface is a surface (upper surface), and emitted light is emitted upward. For this purpose, the incident surface of each first core is the inclined surface 14 so that the emitted light emitted upward is reflected in the lateral direction (light propagation direction) of each first core portion, and each first core portion is reflected. Can be efficiently guided inward.

  In addition, in the present embodiment, the same operations and effects as described in the seventh embodiment are obtained.

Ninth Embodiment In the present embodiment, as shown in the plan view of FIG. 25A and the cross-sectional view of FIG. 25B, light is incident from each of the light incident surfaces 4A, 4B, and 4C in the optical waveguide 40i. The cores 33A, 33B and 33C reaching the exit surface 8 are integrated, and the width of the first core portions 5A ′, 5B ′ and 5C ′ is gradually increased by the linear inclined surface 16 from the middle toward the exit surface side. Except for being narrow, it is the same as in the eighth embodiment described above.

  In the present embodiment, over the length of 1000 μm from the incident surfaces 4A, 4B and 4C of the first portions 5A ′, 5B ′ and 5C ′ to the middle of the first portions 5A ′, 5B ′ and 5C ′. The cross-sections of the cores 33A, 33B and 33C are 50 × 50 μm, and the width gradually decreases from 50 μm to 10 μm over the length of the inclined surface 16 of 2000 μm from this position.

  Further, as shown in FIG. 26A (a cross-sectional view taken along line BB ′ in FIG. 25A), first portions 5A ′, 5B ′, and 5C ′ having a rectangular cross section on the lower clad 11 at a predetermined interval. And an upper clad 12 is formed so as to cover them. Further, as shown in FIG. 26B (cross-sectional view taken along the line CC ′ in FIG. 25A), the first portions 5A ′ and 5B having a narrow cross-sectional rectangle at a predetermined interval on the lower clad 11 are formed. 'And 5C' are provided, and the upper clad 12 is formed so as to cover them. In addition, as shown in FIG. 26C (cross-sectional view taken along the line DD ′ in FIG. 25A), the second portion 6A ′ having a rectangular cross section at a predetermined interval in the upper clad 12 on the lower clad 11; 6B ′ and 6C ′ are provided, and an upper clad 12 is formed so as to cover them. The center lines of the second parts 6A ', 6B' and 6C 'are arranged so as to coincide with the center lines of the first parts 5A', 5B 'and 5C'.

  As shown in FIG. 27, the optical coupling efficiency between the first core portion 5A ′ and the second core portion 6A ′ is obtained by making the width of the first core portions 5A ′, 5B ′ and 5C ′ gradually narrow. Can be improved.

  That is, in this portion, the shape of the optical mode 31 of the first portion 5A ′ represented by the bold line gradually decreases and approaches the shape of the optical mode of the second portion 6A ′ having a smaller width. It becomes easy to match, the optical coupling efficiency can be improved, and the coupling loss of the optical mode 31 due to the change in the size of the core can be reduced. That is, if the core size changes abruptly as in the stepped portion 42 described above, mismatch loss in the optical mode 31 occurs, but the core size is changed gently as described above. The mismatch loss of 31 is reduced, and the coupling loss is reduced.

  In addition, in this embodiment, the same operations and effects as described in the above eighth embodiment can be obtained.

Tenth Embodiment In the present embodiment, as shown in the plan view of FIG. 28A and the cross-sectional view of FIG. 28B, the condensing lens 18 is provided above each LED except that the condensing lens 18 is provided. This is the same as the fourth embodiment.

  In the present embodiment, in the optical waveguide 40j, the convex condensing lens 18 is arranged on the upper surface, which is the light emitting surface of each LED 3R, 3G, and 3B, thereby condensing the emitted light of each LED 3R, 3G, and 3B. Since the light can be incident on the inclined surfaces 14 of the first cores 5A, 5B, and 5C, the coupling loss of this portion can be reduced, and the emitted light can be efficiently incident into the first cores 5A, 5B, and 5C. can do.

  In addition, in the present embodiment, the same operations and effects as described in the fourth embodiment described above can be obtained.

Eleventh Embodiment In the present embodiment, as shown in the plan view of FIG. 29A and the cross-sectional view of FIG. 29B, the bottom surfaces of the second cores 6A, 6B, and 6C are formed in the optical waveguide 40k. , Except for being on the same plane as the bottom surfaces of the first cores 5A, 5B and 5C.

  Further, as shown in FIG. 30A (a cross-sectional view taken along the line BB ′ in FIG. 29A), first cores 5A, 5B, and 5C having a rectangular cross section are provided on the lower clad 19 at predetermined intervals. The upper clad 20 is formed so as to cover them. In addition, as shown in FIG. 30B (a cross-sectional view taken along the line CC ′ in FIG. 29A), the second core 6A having a rectangular cross section at the bottom at a predetermined interval on the lower clad 19, Narrow rectangular first cores 5A, 5B and 5C provided with 6B and 6C, respectively, are provided, and an upper clad 20 is formed so as to cover them. Further, as shown in FIG. 30C (a cross-sectional view taken along the line DD ′ in FIG. 29A), second cores 6A, 6B, and 6C having a rectangular cross section are provided on the lower clad 19 at predetermined intervals. The upper clad 20 is formed so as to cover them. The bottom surfaces of the second cores 6A, 6B and 6C are arranged on the same plane as the bottom surfaces of the first cores 5A, 5B and 5C.

  Next, with reference to FIGS. 31 to 32, a method of manufacturing the optical waveguide 40k and the device will be described.

  First, as shown in FIG. 31A, after disposing a temporary substrate 10a having a predetermined shape and thickness, a lower clad 19 having a predetermined thickness is formed on the temporary substrate 10a.

  Next, as shown in FIG. 31B, a second core 6B having a predetermined shape and thickness is formed at a predetermined position on the lower clad 19.

  Next, as shown in FIG. 31C, the first core 5B having a predetermined shape and thickness is formed on the lower clad 19 and a part of the second core 6B.

  Next, as shown in FIG. 31D, an upper clad 20 having a predetermined thickness is formed on a part of the second core 6B and on the first core 5B.

  Next, as shown in FIG. 32 (e), the end surface side where the lower clad 19, the first core 5B, and the upper clad 20 are sequentially laminated is cut at an angle of 45 ° to obtain a light incident surface on the first core 5B. An inclined surface 14 is formed.

  Next, as shown in FIG. 32 (f), the temporary substrate 10 a is peeled from the bottom surface of the lower clad 19.

  Next, as shown in FIG. 32 (g), the light emitted from the LED 3G is inclined after fixing the bottom surface of the lower clad 19 on the substrate 10 provided with the recess 15 for disposing the LED 3G having the electrode 1A. The LED 3G is disposed so as to enter the first core 5A through the surface 14 to produce the optical waveguide 40k.

  In the present embodiment, since the bottom surfaces of the second cores 6A, 6B, and 6C are arranged on the same plane as the bottom surfaces of the first cores 5A, 5B, and 5C, the manufacturing process of the optical waveguide 40k is reduced. Can be produced relatively easily. This manufacturing process may be similarly applied to the other examples described in the second embodiment and the like, although the method for forming the core and the clad is different.

  In addition, in the present embodiment, the same operations and effects as described in the fourth embodiment described above can be obtained.

Twelfth Embodiment In the present embodiment, as shown in the plan view of FIG. 33A and the cross-sectional view of FIG. 33B, the top surfaces of the second cores 6A, 6B, and 6C are the first core. Except for being on the same plane as the top surfaces of 5A, 5B and 5C, it is the same as in the fourth embodiment described above.

  Further, as shown in FIG. 34A (a cross-sectional view taken along the line BB ′ in FIG. 33A), a first core 5A having a rectangular cross section that is semi-buried at a predetermined interval in a predetermined portion in the lower clad 35, 5B and 5C are provided, and an upper clad 21 is formed so as to cover them. Further, as shown in FIG. 34B (a cross-sectional view taken along the line CC ′ in FIG. 33A), a half-width rectangular cross section is embedded in the lower clad 35 and at a predetermined interval at the top. The first cores 5A, 5B and 5C having a narrow cross section provided with the second cores 6A, 6B and 6C, respectively, are provided, and an upper clad 21 is formed so as to cover them. Also, as shown in FIG. 34C (cross-sectional view taken along the line DD ′ in FIG. 33A), second cores 6A, 6B, and 6C having a rectangular cross section and a square shape are provided on the lower clad 35, An upper clad 21 is formed so as to cover them. The top surfaces of the second cores 6A, 6B and 6C are arranged on the same plane as the top surfaces of the first cores 5A, 5B and 5C.

  In the present embodiment, since the top surfaces of the second cores 6A, 6B, and 6C are arranged on the same plane as the top surfaces of the first cores 5A, 5B, and 5C, the manufacturing process of the optical waveguide 401 is reduced. And can be manufactured relatively easily.

  In addition, in the present embodiment, the same operations and effects as described in the fourth embodiment described above can be obtained.

Thirteenth Embodiment In the present embodiment, as shown in the plan view of FIG. 35A and the cross-sectional view of FIG. 35B, the bottom surfaces of the second core portions 6A ′, 6B ′ and 6C ′ are It is the same as that of the above-mentioned 9th Embodiment except being on the same plane as the bottom face of 1st core part 5A ', 5B', and 5C '.

  Further, as shown in FIG. 36A (a cross-sectional view taken along line BB ′ in FIG. 35A), the first core portions 5A ′ and 5B having a rectangular cross section at predetermined intervals on the lower cladding 19 at predetermined intervals. 'And 5C' are provided, and the upper clad 20 is formed so as to cover them. Further, as shown in FIG. 36B (cross-sectional view taken along the line DD ′ in FIG. 35A), the second core portions 6A ′, 6B ′, and 6C having a rectangular cross section on the lower clad 19 at a predetermined interval. 'Is provided, and an upper clad 20 is formed so as to cover them. The bottom surfaces of the second core portions 6A ', 6B' and 6C 'are arranged on the same plane as the bottom surfaces of the first core portions 5A', 5B 'and 5C'.

  In the present embodiment, since the bottom surfaces of the second core portions 6A ′, 6B ′ and 6C ′ are arranged on the same plane as the bottom surfaces of the first core portions 5A ′, 5B ′ and 5C ′, the optical waveguide The manufacturing process of 40 m can be reduced, and it can be manufactured relatively easily.

  In addition, in this embodiment, the same operations and effects as described in the ninth embodiment are obtained.

Fourteenth Embodiment In the present embodiment, as shown in the plan view of FIG. 37A and the cross-sectional view of FIG. 37B, the top surfaces of the second core portions 6A ′, 6B ′ and 6C ′ are formed. , Except for being on the same plane as the top surfaces of the first core portions 5A ′, 5B ′ and 5C ′.

  Further, as shown in FIG. 38A (a cross-sectional view taken along the line BB ′ in FIG. 37A), the first core portion 5A having a rectangular cross section is embedded in a predetermined portion of the lower cladding 35 halfway at a predetermined interval. '5B' and 5C 'are provided, and an upper clad 21 is formed so as to cover them. Further, as shown in FIG. 38B (a cross-sectional view taken along the line DD ′ in FIG. 37A), second core portions 6A ′, 6B ′, and 6C having a rectangular cross section on the lower cladding 35 at a predetermined interval. 'Is provided, and an upper clad 21 is formed so as to cover them. The top surfaces of the second core portions 6A ', 6B' and 6C 'are arranged on the same plane as the top surfaces of the first core portions 5A', 5B 'and 5C'.

  In the present embodiment, since the top surfaces of the second core portions 6A ′, 6B ′ and 6C ′ are arranged on the same plane as the top surfaces of the first core portions 5A ′, 5B ′ and 5C ′, The manufacturing process of the optical waveguide 40n can be reduced, and the optical waveguide 40n can be manufactured relatively easily.

  In addition, in this embodiment, the same operations and effects as described in the ninth embodiment are obtained.

Fifteenth Embodiment In the present embodiment, as shown in the plan view of FIG. 39, incident light from the LED (G) 3G that sequentially propagates through the first core 5B and the second core 6B, and the first core 5C. In addition, incident light from the LED (B) 3B that sequentially propagates through the second core 6C is merged through the wavelength filter 39 in the merge unit 23. In addition, the combined light propagating through the linear common core 37 and the incident light from the LED (R) 3R sequentially propagating through the first core 5A and the second core 6A are combined in the wavelength filter 23 ′. It is the same as that of the above-mentioned 4th Embodiment except that this joined light which joins via 39 'and propagates the linear common core 38 is radiate | emitted as the emitted light 30 from the output surface 8. FIG.

  In the optical waveguide 40o according to the present embodiment, the groove portions 36 and 36 ′ having a depth of 150 μm, a width of 30 μm, and a length of 1200 μm are formed in the second cores 6A, 6B, 6C, and 45 in the merge portions 23 and 23 ′. The wavelength filters 39 and 39 'are inserted into the grooves 36 and 36'. The size of each common core 37 and 38 is 10 × 10 μm, which is the same as the size of each second core. Further, the first core 5A, the second core 6A, the first core 5C, and the second core 6C are arranged in a direction orthogonal to the first core 5B and the second core 6B.

  In addition, incident light from the LED (G) 3G that sequentially propagates through the first core 5B and the second core 6B is transmitted through the wavelength filter 39 to propagate through the common core 37 and further through the wavelength filter 39 ′. After propagating through the common core 38, the light exits from the exit surface 8. In addition, incident light from the LED (B) 3B that sequentially propagates through the first core 5C and the second core 6C is reflected by the wavelength filter 39, propagates through the common core 37, and further passes through the wavelength filter 39 ′. After propagating through the common core 38, the light exits from the exit surface 8. Incident light from the LED (R) 3R that sequentially propagates through the first core 5A and the second core 6A is reflected by the wavelength filter 39 ', propagates through the common core 38, and then exits from the exit surface 8.

  Further, as shown in FIG. 40A (a cross-sectional view taken along the line BB ′ in FIG. 39), a first core 5B having a rectangular cross section is provided at a predetermined position of the lower clad 11, and the upper clad 12 is covered so as to cover it. Has a formed structure. Further, as shown in FIG. 40B (a cross-sectional view taken along the line CC ′ in FIG. 39), the second core 6B having a narrow cross-sectional rectangle is formed at a predetermined portion of the lower clad 11 at the center thereof. A first core 5B having a narrow rectangular cross section is provided, an upper clad 12 is formed so as to cover the first core 5B, and a wavelength filter 39 is inserted into a groove 36 having a predetermined shape. Further, as shown in FIG. 40C (cross-sectional view taken along the line DD ′ in FIG. 39), a common core 38 having a rectangular cross section is provided at a predetermined position on the lower clad 11, and the upper clad 12 is covered so as to cover this. Is formed.

  According to the present embodiment, compared with the above-described fourth embodiment, since the wavelength filter is provided at the confluence, the second core can be formed in a straight line, and for this reason, the second core Thus, light leakage to the clad as seen when a curved inclined surface exists is less likely to occur, and light can be propagated efficiently. Therefore, the coupling loss at the core junction is reduced and an efficiency of 90% or more can be obtained. Moreover, since the length of the core may be short, the optical waveguide can be miniaturized. Further, each LED (and hence each core) can be arbitrarily arranged on each side of the substrate 10 by a combination with the wavelength filters 23 and 23 ′. Further, as compared with the case where each core is disposed only on one side of the substrate 10, the optical waveguide itself can be reduced in size, and light mixing between different light sources can be prevented. The optical waveguide structure according to this embodiment can be applied to the other embodiments described above.

  In addition, in the present embodiment, the same operations and effects as described in the fourth embodiment described above can be obtained.

Sixteenth Embodiment In the present embodiment, as shown in the plan view of FIG. 41, incident light from an LED (G) 3G propagating through the first core 5B and an LED (B propagating through the first core 5C) ) The incident light from 3B merges through the wavelength filter 39 at the merge section 23. In addition, the combined light propagating through the linear common core 37 ′ and the incident light from the LED (R) 3R propagating through the first core 5A are passed through the wavelength filter 39 ′ at the confluence portion 23 ′. The above-mentioned fifteenth embodiment is the same as the above-described fifteenth embodiment except that the merged light that merges with the common core 38 ′ and sequentially propagates through the common core 50 ′ that is narrower than the common core 38 ′ is emitted from the emission surface 8 as the emission light 30. This is the same as the embodiment. Both the cores 38 ′ and 50 ′ have a structure in which the core 6 is partially embedded in the core 5 similarly to the cores 5 and 6 of the fourth embodiment described above.

  In the optical waveguide 40p of the present embodiment, in each of the merging portions 23 and 23 ′, the groove portions 36 and 36 ′ having a depth of 150 μm, a width of 30 μm, and a length of 1200 μm are formed with the first cores 5A, 5B and 5C. An angle of 45 ° is provided, and wavelength filters 39 and 39 ′ are inserted into the grooves 36 and 36 ′. In addition, the size of the common core 37 ′ is 50 × 50 μm, the width of the common core 38 ′ gradually decreases from 50 × 50 μm to 14 × 14 μm in the light propagation direction, and the size of the common core 50 ′ is 10 ×. × 10 μm.

  Further, the incident light from the LED (G) 3G propagating through the first core 5B is transmitted through the wavelength filter 39 and propagated through the common core 37 ′, and further transmitted through the wavelength filter 39 ′ and transmitted through the common core 38 ′ and After sequentially propagating through the common core 50 ′, the light exits from the exit surface 8. Further, the incident light from the LED (B) 3B propagating through the first core 5C is reflected by the wavelength filter 39 and propagates through the common core 37 ′, and further passes through the wavelength filter 39 ′ to pass through the common core 38 ′ and After sequentially propagating through the common core 50 ′, the light exits from the exit surface 8. Incident light from the LED (R) 3R propagating through the first core 5A is reflected by the wavelength filter 39 ', propagates through the common core 38' and the common core 50 ', and then exits from the exit surface 8.

  According to the present embodiment, since the size of each first core and the second core is 50 × 50 μm and the mode of the propagation light from each first core is large, they are coupled via the wavelength filter. And can propagate light efficiently with low loss.

  In addition, in this embodiment, the same operations and effects as described in the fifteenth embodiment can be obtained.

Seventeenth Embodiment In the present embodiment, as shown in the plan view of FIG. 42B (A) and the sectional view of FIG. 42B (B), the curved inclined surfaces 9 of the second cores 6A, 6B and 6C are provided. It is the same as that of the above-mentioned 1st Embodiment except extending 1st core 5A, 5B, and 5C until it reaches the middle.

  In the optical waveguide 40g of the present embodiment, the first cores 5A, 5B, and 5C are extended to the middle of the curved inclined surfaces 9 of the second cores 6A, 6B, and 6C. The contact area between the second cores 6A, 6B, and 6C and the first cores 5A, 5B, and 5C in the portion 13 is increased, and light propagating through the first cores 5A, 5B, and 5C is transmitted into the second cores 6A, 6B, and 6C. Therefore, it can enter efficiently.

  In addition, in this embodiment, the same operations and effects as described in the first embodiment are obtained.

Eighteenth Embodiment In the present embodiment, as shown in the plan view of FIG. 43A and the cross-sectional view of FIG. 43B, the upper cladding 12 is eliminated, and the second cores 6A, 6B, and 6C Except for forming an air ridge type optical waveguide in which one core 5A, 5B and 5C is exposed, it is the same as in the first embodiment.

  In the optical waveguide 40r of the present embodiment, since the second cores 6A, 6B, and 6C and the first cores 5A, 5B, and 5C are exposed, they are in contact with the air having a lower refractive index than these. As a result, light propagating through the first cores 5A, 5B and 5C and the second cores 6A, 6B and 6C is less likely to leak from the respective cores, and propagates more efficiently and is more focused from the exit surface. Can be emitted.

  In addition, in this embodiment, the same operations and effects as described in the first embodiment are obtained.

Nineteenth Embodiment In the present embodiment, as shown in the plan view of FIG. 44A and the cross-sectional view of FIG. 44B, the second cores 6A, 6B, and 6C that are not embedded in the embedded portion 13 are used. This portion is the same as that of the first embodiment described above except that this portion is exposed in the space 22 between the lower cladding 11.

  In the optical waveguide 40s of the present embodiment, since the portions of the second cores 6A, 6B, and 6C that are not embedded in the embedded portion 13 are exposed to the space 22, they are in contact with the air having a low refractive index. Thus, the light propagating in the second cores 6A, 6B, and 6C is difficult to leak from the core, and the light in the second cores 6A, 6B, and 6C can be propagated more efficiently. Here, the portions of the second cores 6A, 6B, and 6C that are not embedded in the embedded portion 13 are formed on the substrate 10 (lower cladding) by supporting means such as spacers provided on the lower surface of the upper cladding 12 where these second cores do not exist. 11) Desirably supported on top.

  In addition, in this embodiment, the same operations and effects as described in the first embodiment are obtained.

20th Embodiment The plan view of FIG. 45 shows various shapes of the second core 6A in the embedded portion 13 in the first core 5A. The following description also applies to the structures of the second core 6B in the embedded portion 13 in the first core 5B and the second core 6C in the embedded portion 13 in the first core 5C.

  First, as shown in FIG. 45 (A), for example, in the embedded portion 13 in the first core 5A, the first core 5A is provided via the linear second core 6A provided on the center line of the first core 5A. In order to make light propagating in the core 5A easily enter the second core 6A, the tip 41 of the second core 6A forms a circular protrusion 24, and the width thereof is the width of the first core 5A. And almost the same. Accordingly, the optical mode shape of the second core 6A and the optical mode shape of the first core 5A are easily coupled in the vicinity of the tip 41, and the light in the first core 5A is more likely to enter the second core 6A. . The same applies to the other first and second cores (hereinafter the same).

  In the example shown in FIG. 46 (B), in the embedded portion 13 in the first core 5A, the first core 5A is inserted into the first core 5A via the linear second core 6A provided on the center line of the first core 5A. In order for the light propagating through the second core 6A to easily enter the second core 6A, the tip 41 of the second core 6A forms a triangular protrusion 43, and the width thereof is substantially the same as the width of the first core 5A. It is said. Accordingly, similarly to FIG. 46A, the optical mode shape of the second core 6A and the optical mode shape of the first core 5A are easily coupled in the vicinity of the tip 41, and the light in the first core 5A is second. It becomes easy to enter into the core 6A.

  In the example shown in FIG. 46C, in the embedded portion 13 in the first core 5A, there is a portion of the linear second core 6A so as to contact the side surface 44 of the first core 5A, and the first core 5A. Therefore, the size of the optical mode shape of the first core 5A is gradually reduced, so that the second core 6A is gradually reduced in size so that the width of the first core 5A gradually decreases from the incident surface 4A toward the second core 6A. It becomes easy to couple | bond with the light mode shape of this, and the light in the 1st core 5A becomes easy to inject into the 2nd core 6A.

  In the example shown in FIG. 46 (D), in the embedded portion 13 in the first core 5A, the first core 5A is inserted into the first core 5A via the linear second core 6A provided on the center line of the first core 5A. The side surface 44 and the side surface 45 are respectively inclined so that the width of the first core 5A gradually becomes narrower from the incident surface 4A toward the second core 6A so that the light of the first light enters the second core 6A. For this reason, the size of the optical mode shape of the first core 5A is gradually reduced and it becomes easier to combine with the optical mode shape of the second core 6A, and the light in the first core 5A enters the second core 6A. It becomes easy.

Twenty-first Embodiment In the present embodiment, as shown in the cross-sectional view of FIG. 46, for example, the LED (G) 3G has a structure that emits light from both the upper and lower surfaces, and the material of the electrode 1A and the substrate 10 is light transmissive. The second embodiment is the same as the second embodiment except that the optical waveguide structure including the first core 5B and the second core 6B is provided not only on the upper surface of the substrate 10 but also on the lower surface thereof.

  In the optical waveguide 40t of the present embodiment, the emitted light emitted from the upper surface of the LED (G) 3G enters the first core 5B via the inclined surface 14 of the first core 5B, and the incident light 29 is the first light 29 After sequentially propagating through the first core 5B and the second core 6B, the light is emitted as emitted light 30. In addition, at the same time, the emitted light emitted from the lower surface of the LED (G) 3G is sequentially transmitted through the light-transmitting electrode 1A and the substrate 10, and passes through the inclined surface 14 of the first core 5B provided on the lower surface of the substrate 10. The incident light 29 enters the first core 5B through the first core 5B and sequentially propagates through the first core 5B and the second core 6B provided on the lower surface of the substrate 10, and then is emitted as the emitted light 30.

  Therefore, since the substrate 10 is used in common and two emitted lights 30 are obtained at the upper and lower sides thereof, the number of point light sources (that is, the arrangement density of the light sources) can be increased, and the resolution of the image can be increased. I can expect.

  In addition, in the present embodiment, the same operations and effects as described in the second embodiment described above can be obtained.

  The embodiment described above can be variously modified based on the technical idea of the present invention.

  For example, the substrate, each clad, each LED, each core, each first core, each second core, each first part, each shape, size, number of installation, installation location, material, thickness, etc. Various changes may be made as long as a desired effect can be realized. In particular, the number of cores may be one, the number, pattern, size, and the like may be variously changed, and the shape may be changed not only in the width direction of each core but also in the thickness direction. Moreover, you may use an optical fiber for each 2nd part of each core. Moreover, the front-end | tip of the embedding part of each 2nd core may reach the entrance plane of each 1st core.

  Further, by providing the second core separately into a plurality of points, point light sources may be arranged at a plurality of arbitrary positions, and the number thereof may be increased.

  Further, the constituent material and the layer structure of the optical waveguide may be variously changed. For example, an inorganic material such as lithium niobate is used, and this is formed as a core material on a substrate by CVD (chemical vapor deposition), and etched into a predetermined pattern using a resist mask. A core equivalent to this core can be formed.

  The core shape of the optical waveguide is not limited to the type having a linear inclined surface at the end surface in the width direction, but may be a core having a curved inclined surface at the end surface in the width direction. The core may be produced by molding with a mold.

  Further, the configuration of the optical system including the above-described optical waveguide may be appropriately employed. For example, a micromirror device or a polygon mirror may be employed as a scanning unit, or projection may be performed on a screen.

  The present invention includes a display using an LED as a light source, for example, optical communication in which signal light from an optical waveguide is incident on a light receiving element (optical wiring, photodetector, etc.) of a next stage circuit using a laser of emitted light. It is widely applicable to various optical information processing such as

  The present invention provides an optical waveguide that is capable of efficiently entering desired incident light and propagating to and exiting from the light exit side while having a relatively simple structure, and scanning the emitted signal light with a scanning means. It can be effectively used for a display configured to project, or for optical information processing such as optical communication configured to cause the signal light to be incident on a light receiving element (such as an optical wiring or a photodetector) of the next-stage circuit.

1A is a plan view of an optical waveguide device according to a first embodiment of the present invention, and FIG. FIG. 5B is a cross-sectional view taken along line B-B ′, a cross-sectional view taken along line C-C ′, and a cross-sectional view taken along line D-D ′ in FIG. FIG. 6 is a cross-sectional view sequentially showing the manufacturing steps of the optical waveguide device. FIG. 6 is a cross-sectional view sequentially showing the manufacturing steps of the optical waveguide device. It is a top view which shows the manufacturing process of an optical waveguide apparatus sequentially in the same. It is a top view which shows the manufacturing process of an optical waveguide apparatus sequentially in the same. 6A is a plan view of an optical waveguide device according to a second embodiment of the present invention, and FIG. It is the top view (A) and its A-A 'sectional view (B) of the optical waveguide device by a 3rd embodiment of the present invention. FIG. 5B is a cross-sectional view taken along line B-B ′, a cross-sectional view taken along line C-C ′, and a cross-sectional view taken along line D-D ′ in FIG. It is a top view which shows the change of mode shape similarly. 6A is a plan view of an optical waveguide device according to a fourth embodiment of the present invention, and FIG. FIG. 5B is a cross-sectional view taken along line B-B ′, a cross-sectional view taken along line C-C ′, and a cross-sectional view taken along line D-D ′ in FIG. It is a top view which shows the change of mode shape similarly. It is the top view (A) of the optical waveguide device by the 5th Embodiment of this invention, and its A-A 'sectional view (B). FIG. 5B is a cross-sectional view taken along line B-B ′, a cross-sectional view taken along line C-C ′, and a cross-sectional view taken along line D-D ′ in FIG. It is a top view which shows the change of mode shape similarly. It is the top view (A) of the optical waveguide device by the 6th Embodiment of this invention, and its A-A 'sectional view (B). FIG. 5B is a cross-sectional view taken along line B-B ′, a cross-sectional view taken along line C-C ′, and a cross-sectional view taken along line D-D ′ in FIG. It is a top view which shows the change of mode shape similarly. It is the top view (A) of the optical waveguide device by a 7th embodiment of the present invention, and its A-A 'line sectional view (B). FIG. 4 is a cross-sectional view taken along line C-C ′ and a cross-sectional view taken along line D-D ′ of the optical waveguide device (B). FIG. 6 is a cross-sectional view sequentially showing the manufacturing steps of the optical waveguide device. FIG. 6 is a cross-sectional view sequentially showing the manufacturing steps of the optical waveguide device. It is the top view (A) and its A-A 'sectional view (B) of the optical waveguide device by an 8th embodiment of the present invention. It is the top view (A) and its A-A 'sectional view (B) of the optical waveguide device by a 9th embodiment of the present invention. FIG. 5B is a cross-sectional view taken along line B-B ′, a cross-sectional view taken along line C-C ′, and a cross-sectional view taken along line D-D ′ in FIG. It is a top view which shows the change of mode shape similarly. It is the top view (A) and its A-A 'sectional view (B) of the optical waveguide device by a 10th embodiment of the present invention. It is the top view (A) and its A-A 'sectional view (B) of the optical waveguide device by an 11th embodiment of the present invention. FIG. 5B is a cross-sectional view taken along line B-B ′, a cross-sectional view taken along line C-C ′, and a cross-sectional view taken along line D-D ′ in FIG. FIG. 6 is a cross-sectional view sequentially showing the manufacturing steps of the optical waveguide device. FIG. 6 is a cross-sectional view sequentially showing the manufacturing steps of the optical waveguide device. It is the top view (A) and its A-A 'sectional view (B) of the optical waveguide device by a 12th embodiment of the present invention. FIG. 5B is a cross-sectional view taken along line B-B ′, a cross-sectional view taken along line C-C ′, and a cross-sectional view taken along line D-D ′ in FIG. It is the top view (A) of the optical waveguide device by the 13th Embodiment of this invention, and its A-A 'sectional view (B). FIG. 4 is a cross-sectional view taken along line B-B ′ and a cross-sectional view taken along line D-D ′ of the optical waveguide device (B). It is the top view (A) and its A-A 'sectional view (B) of the optical waveguide device by a 14th embodiment of the present invention. FIG. 4 is a cross-sectional view taken along line B-B ′ and a cross-sectional view taken along line D-D ′ of the optical waveguide device (B). It is a top view of the optical waveguide device by a 15th embodiment of the present invention. FIG. 5B is a cross-sectional view taken along line B-B ′, a cross-sectional view taken along line C-C ′, and a cross-sectional view taken along line D-D ′ in FIG. It is a top view of the optical waveguide device by a 16th embodiment of the present invention. It is the top view (A) and its A-A 'sectional view (B) of the optical waveguide device by a 17th embodiment of the present invention. It is the top view (A) of the optical waveguide device by the 18th Embodiment of this invention, and its A-A 'sectional view (B). It is the top view (A) and its A-A 'sectional view (B) of the optical waveguide device by a 19th embodiment of the present invention. It is a top view (A), (B), (C), (D) of an optical waveguide by a 20th embodiment of the present invention. It is sectional drawing of the optical waveguide apparatus by the 21st Embodiment of this invention. It is a block diagram of the image display apparatus by a prior art example. It is a block diagram of another image display apparatus same as the above. FIG. 6 is a plan view (A) of the optical waveguide device and a graph showing the relationship between optical loss and inter-core pitch.

Explanation of symbols

1A, 1B ... electrode, 2 ... metal wire, 3R ... LED (R), 3G ... LED (G),
3B ... LED (B), 4A, 4B, 4C ... incident surface, 5A, 5B, 5C ... first core,
5A ', 5B', 5C '... 1st core part, 5a, 5b ... Core part,
6A, 6B, 6C ... 2nd core, 6A ', 6B', 6C '... 2nd core part,
7, 37, 38 ... common core, 8 ... emitting surface, 9 ... curved inclined surface, 10 ... substrate,
11, 35 ... lower cladding, 11a, 11b ... lower cladding, 12 ... upper cladding,
13 ... buried portion, 14 ... inclined surface, 15 ... concave portion, 16, 17 ... linear inclined surface,
18 ... Condensing lens, 19 ... Lower cladding, 22 ... Space, 23, 23 '... Junction,
25, 28 ... core material, 29 ... incident light, 30 ... outgoing light, 31, 31a, 31b ... mode,
33A, 33B, 33C ... Core, 36, 36 '... Groove, 39, 39' ... Wavelength filter,
40a, 40b, 40c, 40d, 40e, 40f, 40g, 40h, 40i, 40j, 40k, 40l, 40m, 40n, 40o, 40p, 40q, 40r, 40s, 40t ... optical waveguide,
41 ... tip part, 42 ... step part, L ₁ ... length of buried part, L ₂ ... length of first core

Claims (31)

The first core portion having a refractive index higher than that of the clad, and the second core portion having a refractive index higher than that of the first core portion and partially projecting and joined from one end face side of the first core portion. The core is bonded to the cladding,
The other end face of the first core portion is disposed opposite to the light emitting element, and the light incident area of at least the other end face is larger than the light propagation area of the second core portion, and from the junction region with respect to the first core portion. The second core portion is extended to the light emitting side,
Optical waveguide.   The optical waveguide according to claim 1, wherein a light propagation area of the second core portion gradually increases in a light propagation direction.   The optical waveguide according to claim 1, wherein a light propagation area of the second core portion is gradually reduced in a light propagation direction.   The optical waveguide according to claim 2, wherein a light propagation area of the first core portion is gradually reduced in a light propagation direction.   2. The optical waveguide according to claim 1, wherein the other end surface of the first core portion forms an inclined surface, and light from the light emitting element is reflected by the inclined surface and guided into the first core portion.   The optical waveguide according to claim 1, wherein a plurality of the cores are provided, and the second core portions of the cores merge to extend toward the light emitting side.   The plurality of cores are composed of a first core and a second core, and means for selectively transmitting or reflecting light of a specific wavelength is disposed at a merging position of these cores. The optical waveguide according to claim 6, wherein light propagated from the plurality of cores is multiplexed.   A multiplexing means for selectively transmitting or reflecting the light guided from the second core part of the third core and the light guided through the common core part from the joining position; The optical waveguide according to claim 7, wherein the optical waveguide is disposed at a joining position between the three cores and the common core portion.   A plurality of the first core portions are provided, and the first core portions merge to extend to the light emission side, and the second core portion is joined at a position on the light emission side from the merge position. The optical waveguide according to claim 1, wherein the core is provided.   Means for selectively transmitting or reflecting light of a specific wavelength is disposed at the joining position of the plurality of first core portions, and light propagated from the plurality of first core portions through this means is multiplexed. The optical waveguide according to claim 9.   A multiplexing means for selectively transmitting or reflecting the light guided from the third first core part and the light guided through the common core part from the merging position is combined with the third The optical waveguide according to claim 10, wherein the optical waveguide is disposed at a joining position between the first core portion and the common core portion.   The optical waveguide according to claim 1, wherein a center line of the second core portion coincides with a center line of the first core portion.   The optical waveguide according to claim 1, wherein a bottom surface or a top surface of the second core portion is on the same plane as a bottom surface or a top surface of the first core portion.   The optical waveguide according to claim 1, wherein a condensing lens is disposed between the light emitting element and the first core portion. A core having a refractive index higher than that of the clad is joined to the clad, and the core has a structure in which the first core portion and the second core portion are connected,
The end face of the first core portion is disposed opposite to the light emitting element, and at least the light incident area of the end face is larger than the light propagation area of the second core portion,
The second core portion extends from the continuous region with respect to the first core portion to the light emitting side,
Optical waveguide.   The optical waveguide according to claim 15, wherein a step is present between both the core portions at a position where the first core portion and the second core portion are connected.   The optical waveguide according to claim 16, wherein a light propagation area of the first core portion is gradually reduced in a light propagation direction.   The optical waveguide according to claim 15, wherein the end surface of the first core portion forms an inclined surface, and light from the light emitting element is reflected by the inclined surface and guided into the first core portion.   The optical waveguide according to claim 15, wherein a plurality of the cores are provided, and the second core portions of the cores merge to extend toward the light emitting side.   The plurality of cores are composed of a first core and a second core, and means for selectively transmitting or reflecting light of a specific wavelength is disposed at a merging position of these cores. The optical waveguide according to claim 19, wherein light propagated from the plurality of cores is multiplexed.   A multiplexing means for selectively transmitting or reflecting light guided from the second core part of the third core and light guided through the common core part from the joining position; The optical waveguide according to claim 20, wherein the optical waveguide is disposed at a joining position between the three cores and the common core portion.   A plurality of the first core portions are provided, and the first core portions are merged and extended to the light emission side, and the second core portion is continuously provided at a position on the light emission side from the merge position. The optical waveguide according to claim 15, wherein the core is provided.   Means for selectively transmitting or reflecting light of a specific wavelength is disposed at the joining position of the plurality of first core portions, and light propagated from the plurality of first core portions through this means is multiplexed. The optical waveguide according to claim 22, wherein   A combining means for selectively transmitting or reflecting the light guided from the third first core part and the light guided from the joining position through the common core part, joins the third third part. The optical waveguide according to claim 23, wherein the optical waveguide is disposed at a joining position of one core part and the common core part.   The optical waveguide according to claim 15, wherein a center line of the second core portion coincides with a center line of the first core portion.   The optical waveguide according to claim 15, wherein a bottom surface or a top surface of the second core portion exists in the same plane as a bottom surface or a top surface of the first core portion.   The optical waveguide according to claim 15, wherein a condensing lens is disposed between the light emitting element and the first core portion.   An optical waveguide device comprising the optical waveguide according to claim 1 and a light emitting element.   An optical information processing apparatus, wherein the optical waveguide device according to claim 28 is disposed on an optical path.   An optical waveguide device comprising the optical waveguide according to claim 15 and a light emitting element.   An optical information processing apparatus, wherein the optical waveguide device according to claim 30 is disposed on an optical path.

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