WO2019000845A1

WO2019000845A1 - Light collector, light emitting device, and projection light source

Info

Publication number: WO2019000845A1
Application number: PCT/CN2017/114706
Authority: WO
Inventors: 徐梦梦; 胡飞; 李屹
Original assignee: 深圳市光峰光电技术有限公司
Priority date: 2017-06-27
Filing date: 2017-12-06
Publication date: 2019-01-03
Also published as: CN109143745B; CN109143745A

Abstract

Provided are a light collector (2), a light emitting device, and a projection light source. The light collector (2) has a light emergent surface (212), a light incident surface (211, 213), and a side surface (214) opposite the light emergent surface (212). The light collector (2) has a stacked multilayer structure. The multilayer structure comprises at least one core layer (20) located at the center and a cladding layer (21, 22) stacked on two sides of the at least one core layer (20). Light having a first wavelength distribution can penetrate the cladding layer (21, 22), and the at least one core layer (20) can convert the light having the first wavelength distribution into a light having a second wavelength distribution. The side surface (214) is provided with a light blocking element for preventing light leakage, wherein an area of the light incident surface (211, 213) is greater than that of the light emergent surface (212). The light emitting device and the projection light source are provided with the light collector (2) and a light source (11). The invention can suppress a drastic change in the temperature of the light collector (2), thereby preventing a device fault caused by a drastic change in an internal temperature. Furthermore, the invention provides a more even distribution of the thermal field inside the light collector (2), reducing thermal effects.

Description

Light concentrator, illuminating device and projection light source

[0001] The present invention relates to a light concentrator, a light emitting device, and a projection light source. In particular, the present invention relates to a light-emitting concentrator in which a thermal field is uniformly distributed, and a light-emitting device and a projection light source using such a light-emitting concentrator.

Background technique

[0002] In recent years, in the field of spotlight illumination, digital light projection, etc., how to obtain a light source with higher brightness and more energy saving has been a research hotspot. Among them, a light-emitting device using a wavelength converter that converts light of a shorter wavelength into a longer-wavelength light in a highly transparent luminescent material has become a major research direction.

[0003] For example, Philips HLD (High Lumen Density) light source uses a highly transparent luminescent material to convert light with shorter wavelengths into longer wavelength light and extract longer wavelengths on a small area surface. Thus, a high-brightness, small optical expansion light output is achieved. In this light source, the highly transparent luminescent material serves as both condensing and wavelength converting, which may be called a luminescent concentrator.

[0004] The light-emitting concentrator as described above causes heat to accumulate inside thereof due to the Stokes shift during wavelength conversion, resulting in a more severe thermal effect. In the prior art, the concentrating concentrator is typically cooled using an ambient cooling system. However, this method causes uneven distribution of the thermal field inside the illuminating concentrator, which produces a more serious thermal effect, thereby affecting the optical and mechanical properties of the device.

Problem solution

Technical solution

In view of the above problems, the present invention is intended to provide a light-emitting concentrator in which internal temperature transition is uniform and heat effect is reduced, and a light-emitting device using the same.

According to an embodiment of the present invention, there is disclosed a light-emitting concentrator having a light exit surface, a light incident surface, and a contralateral surface opposite to the light exit surface, and the light-emitting gather The device has a stacked multilayer structure. The multilayer structure includes at least one core layer located at a center and a cladding layer laminated on both sides of the at least one core layer, the cladding layer being capable of transmitting light having a first wavelength distribution, At least one core layer is capable of converting light having the first wavelength distribution into light having a second wavelength distribution. The opposite side surface is provided with a light blocking member that prevents light from leaking out, and an area of the light incident surface is larger than an area of the light exit surface.

[0007] Preferably, in the light-emitting concentrator, when the at least one core layer is an odd-numbered layer, the impurity concentration of the rare earth element ions is from the light-emitting concentrator in a stacking direction of the multilayer structure The center of the layer gradually decreases toward both sides; when the at least one core layer is an even layer, the impurity concentration of the rare earth element ions gradually increases from the center of the light-emitting concentrator to both sides in the stacking direction of the multilayer structure Decreasing or gradually decreasing from the center of one of the core layers closest to the center of the light-emitting concentrator to both sides.

In some embodiments, preferably, the at least one core layer is composed of two or more layers of luminescent ceramic layers having different concentrations of rare earth ions. In other embodiments, preferably, the at least one core layer comprises two or more layers of different luminescent ceramic layers. For example, each of the luminescent ceramic layers may be formed of a luminescent ceramic material that is miscible with different rare earth ions.

[0009] Preferably, the shading element may be a specular reflection film. Furthermore, the light-emitting concentrator may additionally be provided with a reflective element which is disposed on at least one surface other than the light incident surface and the light exit surface. For example, the reflective element is a specularly reflective layer having a reflectance greater than 95%; or the reflective element is a layer of diffusely reflective material having a reflectivity greater than 90%.

[0010] Preferably, the light incident surface of the light-emitting concentrator is further provided with an optical film that can only transmit light having the first optical distribution. In some implementations, the optical film can be a dichroic film that is permeable to light having the first wavelength distribution. Alternatively, the optical film may be an angle selective filter film that is only permeable to light having the first wavelength distribution incident at a predetermined range of incident angles.

[0011] In some embodiments, the illuminating concentrator may have a wedge shape such that the area of the light exit surface is smaller than the area of the surface opposite thereto.

[0012] Preferably, the cladding layer is an A1 ₂ 0 ₃ ceramic layer.

[0013] Preferably, the light exiting surface is provided with an optical coupling element optically coupled to the optical concentrator, the optical coupling element having a refractive index equal to or lower than the core layer of the illuminating concentrator and The lowest refractive index in the cladding.

[0014] The present invention also discloses a light emitting device provided with any of the light emitting aggregators and light sources as described above. The light source is disposed toward the light incident surface of the light concentrator, the light source capable Light having the first wavelength distribution is emitted.

The present invention also discloses a projection light source provided with any of the illumination aggregators and light sources as described above.

Advantageous effects of the invention

Beneficial effect

[0016] According to the present invention, a light-emitting concentrator has a multilayer ceramic structure including a core layer and a cladding layer, and in the multilayer structure, the core layer is a luminescent ceramic having a rare earth element, the cladding is a crystal structure and Non-luminescent ceramics with similar physicochemical properties to the core layer but higher thermal conductivity. Due to the above multilayer structure, the core layer which generates heat during the illuminating process does not directly contact the surrounding cooling system, and the cladding layer acts to suppress the temperature of the core layer from being drastically changed between the core layer and the surrounding cooling system, thereby preventing Device failure due to drastic changes in internal temperature. In addition, since the impurity concentration of the rare earth element ions gradually decreases from the center to the both sides in the height direction, the distribution of the quantum dots which generate heat inside the light-emitting concentrator is more uniform, thereby making the heat field distribution more uniform and reducing the thermal effect. It should be understood that the benefits of the present invention are not limited to the above effects, but may be any of the benefits described herein.

Brief description of the drawing

DRAWINGS

1 is a schematic structural view showing a light emitting apparatus according to a first embodiment of the present invention.

2 is a side view and a plan view of a multilayer structure of a light-emitting concentrator in the light-emitting device shown in FIG. 1.

3 is a schematic structural view showing a modification of the light emitting apparatus according to the first embodiment of the present invention.

4 is a schematic view showing a Ce ion concentration distribution in a ceramic thickness direction in a light-emitting concentrator of a light-emitting device according to a first embodiment of the present invention.

[0021] FIG. 5 is a side view and a plan view showing a multilayer structure of a light-emitting concentrator of a light-emitting device according to a second embodiment of the present invention.

6 is a schematic view showing a Ce ion concentration distribution in a ceramic thickness direction in a light-emitting concentrator of a light-emitting device according to a second embodiment of the present invention.

7 is a side view and a plan view showing a multilayer structure of a light-emitting concentrator of a light-emitting device according to a third embodiment of the present invention.

8 is a view showing a ceramic thickness in a light-emitting concentrator of a light-emitting device according to a third embodiment of the present invention. Schematic diagram of the Ce ion concentration distribution in the direction.

9 is a schematic view showing a concentration distribution of Ce ions in a ceramic thickness direction in another light-emitting concentrator of a light-emitting device according to a third embodiment of the present invention.

10 is a side view and a plan view showing a multilayer structure of a light-emitting concentrator of a light-emitting device according to a fourth embodiment of the present invention.

Embodiments of the invention

[0027] Hereinafter, various embodiments in accordance with the present invention will be described in detail with reference to the accompanying drawings. It is to be emphasized that all dimensions in the figures are merely schematic and are not necessarily illustrated in true scale and are therefore not limiting. For example, it should be understood that the thicknesses and thickness ratios of the layers in the multilayer structure of the illustrated light-emitting concentrator are not shown in actual size and scale, and are merely for convenience of illustration.

First Embodiment

1 is a schematic structural view showing a light emitting apparatus according to a first embodiment of the present invention. As shown in Fig. 1, the light-emitting device includes a light source 1 and a light-emitting concentrator 2. The light source 1 includes a substrate 10 and at least one solid state light source 11 disposed on the substrate. The solid state light source 11 can in principle be any type of point source, such as a light emitting diode (LED), a laser diode or an organic light emitting diode (OLED). In the case where a plurality of solid-state light sources 11 are provided, the plurality of solid-state light sources 11 are arranged in the form of a two-dimensional light-emitting array. In the present example, a laser light emitting array composed of a laser diode is taken as an example, and as shown in FIG. 1, light emitted from a plurality of solid-state light sources 11 in the light-emitting array is irradiated to the light incident surface 211 of the light-emitting concentrator 2. . In addition, it is also possible to introduce light emitted from a plurality of laser diodes into the optical fiber and then respectively guide them to the light incident surface of the light-emitting concentrator 2, or the light from the light source 1 can be guided to a luminescent concentration by a specific light distribution by a light shaping device. The light of the device 2 is incident on the surface. Each solid state light source 11 is capable of emitting light having a first wavelength distribution such as, but not limited to, ultraviolet light, blue light, green light, yellow light, or red light. For example, when the solid-state light source 1 1 is a blue light source 吋, the first wavelength distribution is 300 to 550 nm, preferably 380 to 480 nm. Further, when the solid-state light source 11 is an ultraviolet (UV) or violet light source, the first wavelength distribution is 420 nm or less. Further, when the solid-state light source 11 is a red light source, the first wavelength distribution is 600 to 800 nm. When a plurality of solid state light sources 11 are included, the plurality of solid state light sources 11 may also be solid state light sources 11 of two or more different colors.

[0030] As shown in FIG. 2, the illuminating concentrator 2 generally has a height 11 and a width extending in mutually perpendicular directions. W and length L rod or rod-like device. Here, the horizontal direction in FIG. 1 is referred to as the longitudinal direction of the light-emitting concentrator 2, the vertical direction in FIG. 1 is referred to as the height direction of the light-emitting concentrator 2, and the direction perpendicular to the paper surface in FIG. The width direction of the concentrator 2. The light-emitting concentrator 2 has a multilayer ceramic laminate structure in which a core layer and a cladding layer are stacked in the height direction of the light-emitting concentrator 2. The incident light emitted from the light source 1 is irradiated to the outer surface of the outermost cladding of the light-emitting concentrator 2. In other words, the outer surface of the outermost cladding of the light-emitting concentrator 2 is the light incident surface of the light-emitting concentrator 2. 1 shows a three-layer laminated structure in which a light-emitting concentrator 2 is sequentially laminated with a cladding layer 21, a core layer 20, and a cladding layer 22 in a height direction, and an outer surface 211 of the cladding layer 21 is a light incident surface of the light-emitting concentrator 2. It should be understood that the light source 1 may be disposed on both sides of the light-emitting concentrator 2 such that incident light is incident from the sides of the light-emitting concentrator 2 at the same time. In this case, both the outer surface 21 1 of the cladding 21 and the outer surface 213 of the cladding 22 are the light incident surfaces of the light-emitting concentrator 2. One end surface 212 of the light-emitting concentrator 2 extending in the height direction and the width direction is a light-emitting surface. The other end face 212 of the illuminating concentrator 2 opposite to the light exit surface 212 is referred to as a contralateral surface, and is provided with a shading element such as a specular reflection film to ensure that light in the illuminating concentrator 2 does not escape from the opposite side surface 214. leakage. It should be understood that the illuminating concentrator 2 is a rod-like or rod-shaped device, and therefore, the areas of the light exit surface 212 and the opposite side surface 214 are apparently smaller than the areas of the light incident surfaces 211 and 213. Further, preferably, the above-described light shielding members may be provided on the other surfaces of the light-emitting concentrator 2 except the light incident surface, the light exit surface, and the opposite side surface to prevent the light beams traveling in the light-emitting concentrator 2 from being at these surfaces No total reflection occurred and leaked out. Alternatively, other surfaces of the light-emitting concentrator 2 other than the light incident surface, the light exit surface, and the opposite side surface may be roughened to further increase the probability that the light beam is totally reflected.

[0031] It should be understood that the cross section perpendicular to the length direction of the illuminating concentrator 2 may have various shapes such as a square, a rectangle, a circle, a triangle, a polygon, and the like. In addition, the light-emitting concentrator 2 in the present embodiment may be disposed such that the area of the cross-section perpendicular to the longitudinal direction gradually decreases as it approaches the light-emitting surface, so that the area of the light-emitting surface is smaller than that of the light-emitting surface. The area of the surface of the concentrator 2 opposite the light exit surface. For example, the illuminating concentrator 2 may have the shape of a wedge or truncated vertebral body. This enables the area of the light exit surface to be further reduced to achieve better light extraction efficiency.

[0032] In the multilayer laminated structure of the light-emitting concentrator 2, the core layer 20 is made of a luminescent ceramic material capable of converting light of the incident first wavelength distribution into light of the second wavelength distribution. For example, the core layer 20 is a yttrium aluminum garnet (YAG, Y ₃ A1 ₅ 0 ₁₂ ) or yttrium aluminum garnet (LuAG, Lu ₃ A1 ₅ 0 ₁₂ ) ceramic having a rare earth element. . The rare ions of the rare earth element may be cryptic ions such as Ce ³⁺ , Pr ³⁺ , Nd ³⁺ , Sm ³⁺ , Eu ³⁺ , Tb ³⁺ , Dy ³⁺ , Ho ³⁺ , Er ³⁺ , Tm ³⁺ , Yb ³⁺

One or more of the others. Among them, Ce 3+ is preferably used. The cladding layers 21 and 22 are non-luminescent ceramics having a crystal structure and a physicochemical property similar to the core layer but having a higher thermal conductivity. In this example, claddings 21 and 22 are formed of YA G ceramic. It should be noted that the above rare earth elements are not originally miscellaneous in the YAG ceramics for forming the cladding layers 21 and 22, but during the preparation of the light-emitting concentrator 2 (see below), the cryptic ions contained in the core layer 20 The diffusion into the cladding layers 21 and 22 causes the impurity concentration of the rare earth element to gradually decrease from the center to the outer side of the core layer in the lamination direction of the multilayer laminated structure of the light-emitting concentrator 2.

Incident light having a first wavelength distribution enters the light-emitting concentrator 2 from the light incident surface 211 and/or 213, and passes through the cladding 21 or 22 to reach the core layer 20. At least a portion of the incident light having the first wavelength distribution is converted into a laser light having a second wavelength distribution in the core layer 20. The laser is propagating within the illuminating concentrator and directed to the light exit surface 212 under the total reflection between the shading elements of the side surface 214 and the different media, and ultimately exits the light exit surface 212.

[0034] Furthermore, a reflective element may be additionally provided on at least one surface of the light-emitting concentrator 2 other than the light incident surface and the light exit surface. The reflective element 3 may be a specular reflective layer, such as a high anti-silver layer or a high anti-aluminum layer, and the reflectance is preferably greater than 95%; and may also be a diffuse reflective material layer formed of a diffuse reflective material such as Ti0 ₂ or BaSO ^Al ₂ 0 ₃ The reflectance is preferably greater than 90%. Such a reflective element is in non-optical contact with the illuminating concentrator 2, reflecting light escaping from the illuminating concentrator 2, which does not satisfy the total reflection condition, back to the illuminating concentrator 2 and finally to the light exiting surface 212, improving the light transmission efficiency. In the case where the light source 1 illuminates the above-described light-emitting concentrator 2 only from the light incident surface 211 side, an example in which the reflective member 3 is provided on the outer surface 213 of the cladding 22 and the end surface 214 is shown in FIG. Further, in order to improve the light extraction efficiency, an optical coupling element or an optical coupling structure may be disposed at the light exit surface 212. The optical coupling element may be an optical glue, lens or lens array having a refractive index equal to or lower than the lowest refractive index of each core layer and each cladding of the light-emitting concentrator 2, and optically coupled to the optical concentrator. Further, an optical film capable of transmitting only light having a first wavelength distribution may be disposed or coated at a light incident surface of the light-emitting concentrator 2. For example, the optical film may be a dichroic film such that incident light of a first wavelength distribution emitted from the light source can enter the light-emitting concentrator through the dichroic film, and a second wavelength distribution generated within the light-emitting concentrator The laser is totally reflected at the dichroic diaphragm. Alternatively, a filter film may be selected at an angle of incidence on the light incident surface (211, 213) of the polished ceramic, It is only possible to transmit a light beam of a first wavelength that is incident at a predetermined range of incident angles. For example, the angle selective filter film may be a blue light transmissive film selected only by the angle of blue light incident at an incident angle in the range of -8.5° to +8.5°. It should be understood that the range of the above incident angles is merely an example, and may be other angle ranges.

[0035] The prior art light-emitting concentrator has a single-layer structure, so that when the outer surface of the light-emitting concentrator contacts the surrounding cooling system, the outer surface of the light-emitting concentrator is drastically cooled, so that the temperature difference between the inside and the outside of the light-emitting concentrator is large, and the temperature A sharp change, which not only causes uneven distribution of the thermal field inside the illuminating concentrator, but also may cause the device to break due to rapid temperature changes. In the present invention, since the illuminating concentrator 2 has a multi-layer structure, when the illuminating concentrator 2 is cooled using the surrounding cooling system, the cladding having excellent thermal conductivity is in direct contact with the surrounding cooling system, generating heat during the illuminating process. The core layer does not come into direct contact with the surrounding cooling system. The cladding acts between the core layer and the surrounding cooling system to suppress the drastic change of the core temperature, achieving a gentle transition between the temperature of the core layer and the temperature of the surrounding cooling system, preventing the internal temperature from drastically changing. Device failure. Further, during the wavelength conversion process, the rare earth element ions in the luminescent concentrator 2 can be regarded as the quantum points at which heat is generated by the Stokes red shift. In the present invention, the impurity concentration of the rare earth element ions in the luminescent concentrator 2 gradually decreases from the center to the both sides in the height direction. That is to say, the distribution of the quantum dots generating heat gradually decreases from the center to the both sides. Therefore, the thermal field inside the illuminating concentrator 2 is more evenly distributed, reducing the thermal effect.

[0036] Next, a specific preparation method of the light-emitting concentrator 2 will be briefly explained.

[0037] according to Y ₃ A1 ₅ 0 ₁₂ and (¥ !_ _x Ce J ₃ A1 ₅ 0 ₁₂ (where x = 0.001 ~ 0.1, the specific value according to the intensity of the incident light of the light source, the size of the illuminating concentrator, The color temperature and color coordinates of the product, determined by theoretical calculations and experimental analysis. Stoichiometric ratio Weigh high-purity commercial A1 ₂ 0 ₃ powder, Y ₂ 0 3 powder and CeO ₂

Powder. Then, a ceramic body is prepared by using a tape casting process. Among them, a surfactant such as EDS is used as a dispersing agent, and alcohol is used as a solvent, and a vinyl polymer (PVA, PVB or PVC) is used as a binder, and a phthalate plasticizer is used as a plasticizer. The specific steps are as follows: the raw material powder is mixed with a solvent and a dispersing agent into a ball mill for ball-milling mixing; after the mixing is uniform, a binder and a plasticizer are added for secondary ball milling to obtain a slurry; then, the mixture is uniformly mixed. The slurry is placed in a vacuum system to remove air bubbles from the slurry; thereafter, the slurry is formed on a tape casting machine to obtain a cast film , then dry at room temperature for 24 hours. After drying, a precursor cast film of Y ₃ A1 ₅ 0 _{12 and} a precursor cast film of C^ _-x Ce J 3A1 ₅ 0 ₁₂ were obtained, respectively. Next, the precursor cast film is cut according to the design size of the light-emitting concentrator (length 1 and width w as shown in FIG. 2) to obtain a cast film of a corresponding size, in consideration of subsequent sintering of the cast film. The size shrinkage and subsequent machining allowance in the process, the size of the cast film is slightly larger than l*w. The specific value of the size can be determined by theoretical simulation combined with experimental analysis. Then, take! !! The precursor cast film of the sheet (Y, _ _x Ce _x ) ₃ A1 ₅ 0 ₁₂ was laminated, and n, and 11 ₂ pieces of the precursor cast film of ¥ ₃ 1 ₅ 0 ₁₂ were laminated on both sides. Where η. η

The value of ₂ is obtained by comprehensively considering the thickness of each layer (cU, dd ₂ ) of the illuminating concentrator to be obtained, the dimensional shrinkage in the subsequent sintering process, the Ce ion diffusion at the interface of the core layer and the cladding, and the subsequent machining. Factors such as balance are determined by combining theoretical simulations and experimental results. Thereafter, the laminated cast film is placed in an environment of 50 to 90 ° C, and 20-80 is applied.

The pressure of MPa allows the laminated cast films to be better combined. Thereafter, the rubber discharge treatment was carried out at a temperature of 500 to 900 ° C for 12 hours, followed by cold isostatic pressing at a pressure of 200 to 300 MPa to obtain a ceramic green body having a multilayer structure. The ceramic green body was vacuum sintered at a temperature of 1650 to 1850 ° C for 5 to 30 hours to obtain a multilayer ceramic having a multilayer laminated structure. During the sintering process, it was originally located at n. The film (the Ce ion in the Y _x Ce J ₃ Al ₅ 0 ₁₂ cast film (the core layer 20 after sintering) is cast into the Y ₃ A1 ₅ 0 ₁₂ film on both sides (the cladding layers 21 and 22 after sintering) In the finally obtained multilayer ceramic, the Ce ion concentration decreases from the center to the surface. Figure 4 shows the concentration distribution of Ce ions in the height direction in the ceramic of the multilayer structure. The multilayer ceramic was subjected to a polishing treatment to obtain a light-emitting concentrator 2.

Second Embodiment

5 is a side view and a plan view showing a multilayer structure of a light-emitting concentrator of a light-emitting device according to a second embodiment of the present invention.

[0040] A light-emitting device according to a second embodiment of the present invention is different from the light-emitting device of the first embodiment in that: the core layer in the multilayer structure is composed of n layers (n>2, and n is an odd number). The rare earth ions are composed of a luminescent ceramic layer of a heterogeneous concentration, and the rarer ion concentration of the luminescent ceramic layer closer to the center is higher. Compared with the illuminating device of the first embodiment, the transition from the center to the both sides of the illuminating concentrator 2 is more gradual, so that the thermal field distribution in the illuminating concentrator 2 is more uniform, further reducing the thermal effect. . Except for this, the illuminating device is almost identical in construction to the illuminating device of the first embodiment, The repeated explanation will be omitted below.

[0041] Hereinafter, a case where the core layer is sintered by two kinds of YAG: Ce luminescent ceramic layers having different Ce ion concentrations will be exemplified with reference to FIG. 5, and the preparation of the luminescent concentrator 2 in this example will be briefly described. method. In the example shown in Fig. 5, three core layers are provided, that is, n=3.

[0042] according to Y ₃ A1 ₅ 0 ₁₂ , (Y !_ _a Ce _a ) ₃ A1 ₅ 0 ₁₂ fP(Y _b Ce _b ) ₃ A1 ₅ 0 ₁₂ (where x=0.001~0.1, and a>b, The specific value is based on the intensity of the incident light of the light source, the size of the illuminating concentrator, the color temperature and color coordinates of the product, and the stoichiometric ratio determined by theoretical calculation and experimental analysis. The high purity commercial A1 ₂ 0 _{3 is} weighed. Powder, ¥ ₂ 0 ₃ powder and ^0 ₂ powder. Then, a ceramic body is prepared by using a tape casting process. Among them, a surfactant such as EDS is used as a dispersing agent, and alcohol is used as a solvent, and a vinyl polymer (PVA, PVB or PVC) is used as a binder, and a phthalate plasticizer is used as a plasticizer. The specific steps are as follows: the raw material powder is mixed with a solvent and a dispersing agent into a ball mill for ball-milling mixing; after the mixing is uniform, a binder and a plasticizer are added for secondary ball milling to obtain a slurry; then, the mixture is uniformly mixed. The slurry was placed in a vacuum system to remove air bubbles in the slurry; thereafter, the slurry was molded on a tape casting machine to obtain a cast film, which was then dried at room temperature for 24 hours. After drying, a precursor cast film of Y ₃ A1 ₅ 0 _{12 ,} a precursor cast film of (Y !_ _a Ce _a ) ₃ A1 ₅ 0 ₁₂ and (Y ^Ce _b ) ₃ Al ₅ 0 _{12 were obtained, respectively.} The precursor cast film. Next, the precursor cast film is cut according to the design size of the light-emitting concentrator (length 1 and width w as shown in FIG. 5) to obtain a cast film of a corresponding size, in consideration of subsequent sintering of the cast film. The size shrinkage and subsequent machining allowance in the process, the size of the cast film is slightly larger than l*w. The specific value of the size can be determined by theoretical simulation combined with experimental analysis. Then, the sheet take n _Q (Y, _a Ce precursor casting membrane J ₃ A1 ₅ 0 ₁₂ are laminated, and are then laminated on both sides as shown in FIG n ₃ and n ₄ pieces (Y! _ _B Ce _b ) ₃ A1 ₅ 0 ₁₂ precursor cast film and n

₂ sheets of Υ ₃ Α _{1 5} 0 ₁₂ precursor cast film. Where η. , _{η ι} , η ₂ , η

The value of ₄ is obtained by comprehensively considering the thickness (d, , d ₂ , d ₃ , d ₄ ) of each layer of the light-emitting concentrator to be obtained, the dimensional shrinkage in the subsequent sintering process, and the Ce at the interface of each layer. Factors such as ion diffusion and subsequent machining allowances are determined in conjunction with theoretical simulations and experimental results. Thereafter, the laminated cast film is placed in an environment of 50 to 90 ° C, and 20-80 is applied.

The pressure of MPa allows the laminated cast films to be better combined. Thereafter, the rubber is discharged at a temperature of 500 to 900 ° C for 12 hours, and then cold isostatic pressing at a pressure of 200 to 300 MPa is obtained. A ceramic green body having a multilayer structure. The ceramic green body was vacuum sintered at a temperature of 1650 to 1850 ° C for 5 to 30 hours to obtain a multilayer ceramic having a multilayer laminated structure. Compared to Example 1, since the core layer is n located at the center. a sheet (Y !_ _a Ce J ₃ A1 ₅ 0 ₁₂ cast film and a precursor cast film on both sides of n ₃ and η (Υ i_ _b Ce _b ) ₃ A1 ₅ 0 ₁₂ , and a >b, the diffusion of Ce ions from the core layer to the cladding during sintering is more moderate. Thus, as shown in Fig. 6, the variation of the Ce ion concentration in the stacking direction is more gentle in this embodiment, and can be further reduced. Thermal effect.

Third Embodiment

In the second embodiment, the core layer in the multilayer structure is composed of an odd-numbered luminescent ceramic layer having different rare earth ion concentrations. In this case, the higher the rare earth ion concentration of the luminescent ceramic layer closer to the center, the higher the core layer at the center has the highest impurity concentration. In the third embodiment, the core layer in the multilayer structure is composed of an n-layer (n≥2, and n is an even number) luminescent ceramic layer having different rare earth ion impurity concentrations, and the closer to the center of the luminescence The higher the rare earth ion concentration of the ceramic layer. Except for this, the configuration of the light-emitting device is almost the same as that of the light-emitting device of the third embodiment, and therefore repeated explanation will be omitted below.

[0045] It should be understood that, in the present embodiment, as shown in FIG. 7, the core layer in the multilayer structure is an illuminating ceramic layer having a different rare earth ion impurity concentration in an even layer (two layers in the figure). Thus, there is no core layer 20 at the center of the light-emitting concentrator as shown in Fig. 5, but the core layers 20 and 23 are collectively located at the position closest to the center of the luminescent ceramic layer. In this case, if the two core layers (e.g., the core layer 20 and the core layer 23 in the drawing) are the same distance from the center of the light-emitting concentrator 2, they are sintered by the luminescent ceramic material containing the same rare earth ion concentration. Then, as shown in FIG. 8, in the multi-layered structure after sintering, the impurity concentration of the rare earth element ions in the luminescent ceramic layer is gradually decreased from the center to the both sides in the lamination direction of the multilayer structure. of. If the two core layers at the same distance from the center of the illuminating concentrator 2 are sintered by a luminescent ceramic material containing different concentrations of rare earth ions, the peak of the rare earth ion concentration is no longer located in the luminescent concentrator 2 The center, but appears in the center of the core layer having a higher rare earth ion concentration in the two core layers closest to the center of the light-emitting concentrator 2. FIG. 9 shows a case where the light-emitting concentrator 2 is provided with two core layers 20 and 23 and the rare earth ions in the core layer 20 have a dense concentration greater than that of the rare earth ions in the core layer 23. It should be understood that, in this case, although the peak position of the rare earth ion impurity concentration in the light-emitting concentrator 2 is shifted from the center of the light-emitting concentrator 2, as a whole, The rare earth ion concentration in the light concentrator 2 is still gradually decreased from the inside to the outside in the thickness direction. Therefore, compared with the illuminating device of the first embodiment, the transition of the impurity concentration of the rare earth ions in the illuminating concentrator 2 of the present embodiment is more gradual, so that the thermal field distribution in the illuminating concentrator 2 is more uniform, further reducing Thermal effect.

Fourth Embodiment

10 is a side view and a plan view showing a multilayer structure of a light-emitting concentrator of a light-emitting device according to a fourth embodiment of the present invention. The illuminating device according to the fourth embodiment of the present invention is different from the illuminating device of the first embodiment in that the core layer in the multilayer structure includes two or more layers of different luminescent ceramic layers. Except for this, the configuration of the light-emitting device is almost the same as that of the light-emitting device of the first embodiment, and thus the repeated description will be omitted below.

[0048] The different luminescent ceramic layers in the core layer are formed from luminescent ceramic materials that are miscellaneous with different rare earth ions. In the example of Fig. 10, in order to obtain a white light output with a high color rendering index, (Y.Ce _ε ) ₃ A1 50 ₁₂ ceramics (where c = 0.001 to 0.1), the specific value is based on the intensity of the incident light of the light source, and the luminescence is concentrated. The size of the device, the color temperature and color coordinates of the product, determined by theoretical calculations and experimental analysis) to form the core layer 20, using (Υ, - _d Eu _d ) ₃ Al ₅ 0 ₁₂ (where d = 0.001 ~ 0.1, specific The value is determined by the theoretical calculation and experimental analysis according to the intensity of the incident light of the light source, the size of the illuminating concentrator, the color temperature and color coordinates of the product, and the ceramic layer 25 is formed. D2, d5, d0 and dl in the figure indicate the thickness of each layer. During the sintering process, the Ce ions in the cast film constituting the core layer 20 and the Eu ions in the cast film constituting the core layer 25 are also diffused from the layer to the outer side of the layer, so that according to the present embodiment, In the luminescent concentrator 2 of the example, the impurity concentration of the rare earth ions is still decreasing from the center to both sides as a whole.

Further, in this example, since two YAG luminescent ceramic core layers containing different dent ions are provided, light having a first wavelength distribution emitted from the light source 1 passes through the light incident surface 211 of the luminescent concentrator 2 and And/or 213 enters the illuminating concentrator, at least a portion of the incident light having the first wavelength distribution is converted into a laser light having a second wavelength distribution by the Ce-doped core layer 20, and is guided to the light by total reflection. The exit surface 212 exits; at least a portion of the incident light having the first wavelength distribution is converted into a laser having a third wavelength distribution by the Eu-doped core layer 25, and is guided to the light exit surface 212 by total reflection. Exit. It is to be noted that a portion of the received laser light having a second wavelength distribution generated in the core layer 20 may enter the core layer 25 and be secondarily converted into a laser light having a third wavelength distribution, and vice versa. By regulating each The thickness of the layer, the parameters of various rare earth ions, and the like can adjust the ratio of the light having the first wavelength distribution, the second wavelength distribution, and the third wavelength distribution among the light emitted from the light exit surface 212, thereby obtaining a desired color. Light output. Therefore, the light-emitting device according to the present embodiment can achieve more desirable control of the color temperature and color coordinates of the output light in addition to the advantages of the foregoing embodiments.

[0050] The manufacturing method of the light-emitting concentrator 2 according to the present embodiment is similar to the preparation methods in the first embodiment and the second embodiment except that the materials, the order and the number of the layers are slightly different, and the like. I won't go into details.

Fifth Embodiment

A light-emitting device according to a fifth embodiment of the present invention is a modification of the light-emitting device of the first embodiment. The illuminating device of the present embodiment is different from the illuminating device of the first embodiment in that the cladding layers 21 and 22 are composed of A1 ₂ 0 ₃ ceramics. Compared with the cladding composed of YAG ceramic in Embodiment 1, the cladding composed of A1 ₂ 0 ₃ ceramic has higher thermal conductivity, so that the thermal effect of the luminescent concentrator in the illuminating device can be more effectively reduced. .

[0053] A method of preparing a light-emitting concentrator in the light-emitting device according to the present embodiment will be briefly explained below.

[0054] according to A1 ₂ 0 ₃ and (Y !_ _x Ce J ₃ A1 ₅ 0 ₁₂ (where x = 0.001 ~ 0.1, the specific value depends on the intensity of the incident light of the light source, the size of the light-emitting concentrator, and the color temperature of the product The requirements of the color coordinates are determined by theoretical calculations and experimental analysis. The stoichiometric ratio is used to weigh high-purity commercial A1 ₂ 0 ₃ powder, Y ₂ 0 ₃ powder and Ce0 ₂ powder. Then, cast molding The ceramic body is prepared by a process. Among them, a surfactant such as EDS is used as a dispersing agent, and alcohol is used as a solvent, and a vinyl polymer (PVA, PVB or PVC) is used as a binder, and a phthalate plasticizer is selected. As a plasticizer. Since the sintering temperature of dense A1 20 ₃ ceramics is higher than that of dense (Y ^Ce J ₃ A1 ₅ 0 ₁₂ ceramics sintering temperature, in order to sinter at the same temperature to obtain dense A1 ₂ 0 3 & ( Y , _ _x Ce J ₃ A1 ₅ 0 ₁₂ & A1 ₂ 0 ₃ Ceramics with a multilayer structure, it is necessary to add a sintering aid such as MgO and/or TEOS to the original slurry of A1 ₂ 0 ₃ ceramics. After the powder is uniformly mixed with the solvent and the dispersant, the binder and plasticization are added. The agent is subjected to secondary ball milling to obtain a slurry; the uniformly mixed slurry is placed in a vacuum system to remove bubbles in the slurry; thereafter, the slurry is formed on a tape casting machine to obtain a cast film, and then at room temperature After drying for 24 h, after drying, a precursor cast film of Al ₂ 0 _{3 and} a precursor cast film of (Y , _x Ce _x ) ₃ A1 ₅ 0 ₁₂ were respectively obtained. Next, according to the design size of the light-emitting collector ( Length 1 and width w) as shown in Figure 2, cutting precursor casting Membrane, a cast film of corresponding size is obtained. Considering the dimensional shrinkage and subsequent machining allowance of the cast film in the subsequent sintering process, the size of the cast film is slightly larger than l*w. The specific value of the size can be determined by theoretical simulation combined with experimental analysis. Then, take n. The precursor casting film of the sheet (Y, _x Ce J ₃ A1 ₅ 0 ₁₂ is laminated, and n is further laminated on both sides, and !1 ₂ pieces of A1 ₂ 0 3

The precursor casts the diaphragm. Where η. η

The value of ₂ is obtained by comprehensively considering the thickness of each layer (cU, dd ₂ ) of the illuminating concentrator to be obtained, the dimensional shrinkage in the subsequent sintering process, the Ce ion diffusion at the interface of the core layer and the cladding, and the subsequent machining. Factors such as balance are determined by combining theoretical simulations and experimental results. Thereafter, the laminated cast film is placed in an environment of 50 to 90 ° C, and a pressure of 20 to 80 MPa is applied, so that the stacked cast films can be well bonded. Thereafter, the rubber discharge treatment was carried out at a temperature of 500 to 900 ° C for 12 hours, followed by cold isostatic pressing at a pressure of 200 to 300 MPa to obtain a ceramic green body having a multilayer structure. The ceramic green body was vacuum sintered at a temperature of 1650 to 1850 ° C for 5 to 30 hours to obtain a multilayer ceramic having a multilayer laminated structure. During the sintering process, the Ce ions originally located in the η Λ (Υ _x Ce J ₃ A1 ₅ 0 ₁₂ cast film (the core layer 20 after sintering) are cast into the A1 ₂ 0 ₃ film on both sides (sintered after sintering) Diffusion in the cladding layers 21 and 22). In the finally obtained multilayer ceramic, the Ce ion concentration decreases from the center to the surface. Finally, the multilayer ceramic obtained by sintering is polished and covered at one end of the multilayer ceramic. A highly reflective film or a total reflection film, a light-emitting concentrator 2 for a light-emitting device according to a fifth embodiment of the present invention is obtained.

[0055] It should be understood that in the light-emitting devices of the second to fourth embodiments, the cladding of the light-emitting concentrator 2 may also be composed of Al ₂ 0 ₃ ceramic as described above.

[0056] Although the illuminating device according to the present invention has been described above with reference to the accompanying drawings, the invention is not limited thereto, and those skilled in the art should understand that the substance or scope defined by the appended claims In this case, various changes, combinations, sub-combinations, and variations can be made.

Claims

Claim

[Claim 1] 1. A light-emitting concentrator having a light exit surface, a light incident surface, and a contralateral surface opposite to the light exit surface, wherein

The illuminating concentrator has a laminated multi-layer structure including at least one core layer located at a center and a cladding layer laminated on both sides of the at least one core layer, the cladding layer being permeable to having Light of a first wavelength distribution, the at least one core layer capable of converting light having the first wavelength distribution into light having a second wavelength distribution, and the opposite side surface is provided with a light blocking member that prevents light from leaking, And the area of the light incident surface is larger than the area of the light exit surface.

[Claim 2] 2. The illuminating concentrator according to claim 1, wherein in the illuminating aggregator,

The viscous concentration of the rare earth element ions gradually decreases from the center to the both sides of the light-emitting collector in the stacking direction of the multilayer structure; or

The impurity concentration of the rare earth element ions gradually decreases from the center of one core layer closest to the center of the light-emitting concentrator to both sides.

[Claim 3] The light-emitting concentrator according to claim 2, wherein the at least one core layer comprises two or more layers of luminescent ceramic layers having different concentrations of rare earth ions .

[Aspect 4] The illuminating concentrator according to claim 2, wherein the at least one core layer comprises two or more layers of different luminescent ceramic layers.

[Attachment 5] The luminescent concentrator according to claim 4, wherein each of the luminescent ceramic layers is formed of a luminescent ceramic material having a different rare earth element ion.

[Attachment 6] The illuminating concentrator according to claim 1, wherein: the illuminating concentrator The light shielding member is also provided at least one surface other than the light incident surface, the light exit surface, and the opposite side surface.

The illuminating concentrator according to any one of claims 1 to 6, wherein the light shielding element is a specular reflection film.

[Aspect 8] The illuminating concentrator according to any one of claims 1 to 6, wherein the illuminating concentrator is further provided with a reflecting element, the reflecting element being disposed except for the light incident surface And at least one surface other than the light exiting surface.

[Aspect 9] The illuminating concentrator according to claim 8, wherein the reflective element is a specular reflection layer having a reflectance greater than ₉₅ <3⁄4; or the reflective element is a diffuse having a reflectance greater than 90% A layer of reflective material.

The illuminating concentrator according to any one of claims 1 to 6, wherein the light incident surface of the illuminating concentrator is further provided with only the first An optical film of optically distributed light.

[Aspect 11] The illuminating concentrator according to claim 10, wherein the optical film is a dichroic film capable of transmitting light having the first wavelength distribution, or is permeable only An angle selective filter film of light having the first wavelength distribution incident at a predetermined range of incident angles

The illuminating concentrator according to any one of claims 1 to 6, wherein the illuminating concentrator has a wedge shape such that an area of the light exiting surface is smaller than an area of a surface opposite thereto .

[Aspect 13] The illuminating concentrator according to any one of claims 1 to 6, wherein the package The layer is an A1 ₂ 0 ₃ ceramic layer.

[Aspect 14] The illuminating concentrator according to any one of claims 1 to 6, wherein an optical coupling element optically coupled to the optical concentrator is disposed on the light exiting surface, the light The refractive index of the coupling element is equal to or lower than the lowest refractive index in the core layer and the cladding of the light-emitting concentrator.

[Claim 15] 15. A light-emitting device, wherein the light-emitting device comprises:

A luminescent concentrator according to any one of claims 1 to 14;

a light source, the light source being disposed toward the light incident surface of the light concentrator, the light source being capable of emitting light having the first wavelength distribution.

[Claim 16] A projection light source, characterized in that the projection light source comprises the light-emitting concentrator according to any one of claims 1 to 14.