JP2018156731A - Illumination device and luminous flux control member - Google Patents

Abstract

The present invention achieves uniform surface light emission without the need for individual adjustment of light emitting elements in light emission by mixing colors of light emitting elements of a plurality of colors.
A light beam control member is arranged so that light emitted from a first light-emitting element and a second light-emitting element that emit light of different colors arranged side by side in an X direction is emitted in an X direction and a Z direction orthogonal thereto. The light distribution of the emitted light is controlled so as to expand and expand in the Y direction orthogonal to both directions. The light flux controlling member 130 controls the light distribution of the emitted light so that the emitted light of each light emitting element reaches a specific range in the X direction, particularly immediately above both light emitting elements.
[Selection] Figure 7

Description

  The present invention relates to an illumination device and a light flux controlling member.

  In recent years, lighting devices using light-emitting diodes (hereinafter also referred to as “LEDs”) as light sources have been used from the viewpoint of energy saving and environmental conservation. Examples of such an illuminating device include a bulb-type illuminating device having an LED as a light source, a fluorescent tube-type illuminating device, and a surface light source device having a plurality of LEDs arranged on a plane as a light source.

  Since the LED is small, it is effective in reducing the size and thickness of the lighting device. For this reason, the said surface light source device is useful as a backlight of a liquid crystal besides the use which illuminates the room. As the surface light source device for the backlight, a surface light source device in which LEDs of a plurality of colors are regularly arranged in a plane direction is known. This surface light source device suppresses the occurrence of local color unevenness by a specific regular arrangement of LEDs (see, for example, Patent Document 1).

JP 2012-104731 A

  However, in the surface light source device in which LEDs of a plurality of colors are arranged, in order to realize surface light emission with uniform color or brightness, the pitch between LEDs, the LED arrangement, the light emission intensity of each LED, etc. Adjustment of various conditions may be required. For this reason, a surface light source device is required to achieve uniform surface light emission without requiring individual adjustment of LEDs.

  It is an object of the present invention to realize uniform light emission without requiring individual adjustment of light emitting elements in light emission by mixing colors of light emitting elements of a plurality of colors.

  As a first means for solving the above-mentioned problems, the present invention is arranged in a first direction, and the second colors are different from each other in emission color and orthogonal to the first direction. A first light emitting element and a second light emitting element each having an optical axis along the direction; a light flux controlling member that covers the first and second light emitting elements from the second direction; and the light flux control in the second direction. A light diffusing member disposed at a position away from the member, wherein the light flux controlling member covers the first light emitting element and the second light emitting element away from them from the second direction. The incident portion that receives the emitted light from the first light emitting element and the second light emitting element, and a part of the light incident from the incident portion is made to be perpendicular to the first direction and the second direction. For total reflection in the direction The reflection portion and the total reflection portion in the third direction are arranged at positions adjacent to the optical axis side ends of the first light emitting element and the second light emitting element, and the light incident from the incident portion An outgoing part for emitting the other part outward and an end of the total reflection part extending in the third direction from the end opposite to the optical axis in the third direction. A light guide portion for guiding the light in the third direction and emitting the light outward, and the lighting device includes a light axis of the first light emitting element and a cross section including the light axis of the second light emitting element. The intersection of one light emitting element of the first light emitting element and the second light emitting element and its optical axis is A1, and the other light emitting element of the first light emitting element and the second light emitting element is the first light emitting element in the first direction. The end on the one element side is A2, and the one light emitting element in the emitting portion is B1 is the end on the other light emitting element side in the first direction of the part through which the emitted light passes, and the first part of the part through which the emitted light of the other light emitting element passes in the emitting part. The end opposite to the one light emitting element in the direction is B2, the intersection point with the straight diffusion member passing through A1 and B1, C1, and the straight diffusion member passing through A2 and B2 When the intersection point is C2, the C1 provides an illuminating device located on the outer side in the first direction than the C2.

  In addition, the present invention provides the light flux controlling member used in the illumination device as a second means for solving the above-described problem, wherein the exit part and the entrance part are both one, In the first direction, there is provided a light flux controlling member in which the positions of both ends of the emitting portion are positions separated from the positions of the optical axes of the first light emitting element and the second light emitting element.

  According to the present invention, it is possible to achieve uniform surface light emission without the need for individual adjustment of light emitting elements in light emission due to color mixing of light emitting elements of multiple colors.

FIG. 1A is a plan view schematically showing the illumination device (surface light source device) according to the first embodiment of the present invention, and FIG. 1B is an enlarged view of a portion B in FIG. 1A. FIG. 1C is an enlarged view showing a main part of a cross section of the illumination device taken along line CC in FIG. 1A. 2A is a perspective view from the front surface side of the light flux controlling member in the first embodiment, and FIG. 2B is a perspective view from the back surface side of the light flux controlling member. 3A is a front view of the light flux controlling member in the first embodiment, FIG. 3B is a plan view of the light flux controlling member, and FIG. 3C is a bottom view of the light flux controlling member. 3D is a side view of the light flux controlling member. 4A is a diagram showing a cross section taken along line AA in FIG. 3B of the light flux controlling member in the first embodiment, and FIG. 4B is taken along line BB in FIG. 3B of the light flux controlling member. It is a figure which shows a cross section. 5A is a front view of the light scattering member in the first embodiment, FIG. 5B is a bottom view of the light scattering member, and FIG. 5C is a side view of the light scattering member. 5D is a cross-sectional view taken along line DD in FIG. 5B of the light scattering member. FIG. 6A is a diagram schematically showing a positional relationship between the light flux controlling member and the light emitting element in the first embodiment for the purpose of explanation, and FIG. 6B is an XY diagram from the light emitting element. It is a figure for demonstrating the outgoing angle of the emitted light in a plane. FIG. 7A is a diagram schematically showing a light emitting element and a light flux controlling member in the surface light source device E1 according to the first example of the first embodiment, and FIG. 7B is a diagram showing the light flux of the surface light source device E1. FIG. 7C is a diagram showing the relationship between the position in the X direction of the central portion of the control member in the Z direction and the chromaticity of the light that illuminates the cover, and FIG. 7C shows the central portion of the surface light source device E1 in the Z direction of the light flux controlling member. It is a figure which shows the relationship between the position in X direction, and the illumination intensity in the cover of the emitted light derived from each of the 1st, 2nd light emitting element from an output part. It is a figure which shows the relationship between the emission angle of the emitted light of an example of the 1st light emitting element in embodiment of this invention, and a 2nd light emitting element, and its luminous intensity. FIG. 9A is a diagram schematically showing an emission angle of emitted light of the light emitting element in the light flux controlling member of the surface light source device E2 according to the second example in the first embodiment, and FIG. FIG. 9C is a diagram showing the relationship between the position in the X direction of the central portion in the Y direction of the light flux controlling member of the surface light source device E2 and the chromaticity of light that illuminates the cover, and FIG. 9C shows the light flux of the surface light source device E2. It is a figure which shows the relationship between the position in the X direction of the center part in the Y direction of a control member, and the illumination intensity in the cover of the emitted light originating in each of the 1st, 2nd light emitting element from an emission part. FIG. 10A is a diagram schematically showing an emission angle of emitted light of the light emitting element in the light flux controlling member of the surface light source device C1 according to the first example in the comparative example of the present invention, and FIG. 10B is a surface light source. It is a figure which shows the relationship between the position in the X direction of the center part in the Y direction of the light beam control member in the above in the apparatus C1 and the chromaticity of the light that illuminates the cover, and FIG. 10C shows the light beam in the surface light source device C1 in the above. It is a figure which shows the relationship between the position in the X direction of the center part in the Y direction of a control member, and the illumination intensity in the cover of the emitted light originating in each of the 1st, 2nd light emitting element from an emission part. FIG. 11A is a diagram schematically showing an emission angle of emitted light of the light emitting element and the light flux controlling member in the surface light source device E3 according to the third example of the first embodiment, and FIG. 11B is a surface light source. It is a figure which shows the relationship between the position in the X direction of the center part in the Z direction of the said light beam control member in the apparatus E3, and the chromaticity of the light which illuminates a cover, FIG. 11C shows Z of the said light beam control member in the surface light source device E3. It is a figure which shows the relationship between the position in the X direction of the center part in a direction, and the illumination intensity in the cover of the emitted light derived from each of the 1st, 2nd light emitting element from an output part. FIG. 12A is a perspective view from the front surface side of the light flux controlling member in the second embodiment of the present invention, and FIG. 12B is a perspective view from the back surface side of the light flux controlling member. FIG. 13A is a front view of the light flux controlling member in the second embodiment, FIG. 13B is a plan view of the light flux controlling member, and FIG. 13C is a bottom view of the light flux controlling member. 13D is a side view of the light flux controlling member. 14A is a view showing a cross section taken along line AA in FIG. 13B of the light flux controlling member in the second embodiment, and FIG. 14B is taken along line BB in FIG. 13B of the light flux controlling member. It is a figure which shows a cross section. FIG. 15A is a diagram schematically showing an emission angle of emitted light of the light emitting element and the light flux controlling member in the surface light source device in the second embodiment, and FIG. 15B is an example of the second embodiment. The relationship between the position in the X direction of the central portion in the Z direction of the light flux controlling member in the surface light source device E4 and the illuminance at the cover of the emitted light derived from each of the first and second light emitting elements from the emitting portion FIG. 15C is a diagram illustrating the position in the X direction of the central portion in the Z direction of the light flux controlling member in the surface light source device E5 of another example of the second embodiment, and the first from the emitting portion. It is a figure which shows the relationship with the illumination intensity in the cover of the emitted light originating in each of a 2nd light emitting element. FIG. 16A is a perspective view from the front surface side of the light flux controlling member in the third embodiment of the present invention, and FIG. 16B is a perspective view from the back surface side of the light flux controlling member. FIG. 17A is a bottom view of the light flux controlling member in the third embodiment, FIG. 17B is a view showing a cross section of the light flux controlling member taken along line BB in FIG. 17A, and FIG. It is a figure which shows the cross section which follows the CC line | wire in FIG. 17A of a light beam control member. It is a figure which shows typically the outgoing angle of the emitted light of the light emitting element in the light beam control member in 3rd Embodiment. FIG. 19A is a diagram schematically illustrating an emission angle of light emitted from the light emitting element and the light flux controlling member in the surface light source device E6 as an example in the fourth embodiment of the present invention, and FIG. 19B illustrates the surface light source device E6. FIG. 19C is a diagram showing the relationship between the position in the X direction of the central portion in the Z direction of the light flux controlling member in FIG. 5B and the chromaticity of the light that illuminates the cover, and FIG. It is a figure which shows the relationship between the position in this, and the illumination intensity in the cover of the emitted light derived from each of the 1st, 2nd light emitting element from an output part. FIG. 20A is a diagram schematically showing an emission angle of light emitted from a light emitting element and a light flux controlling member in another example of the surface light source device E7 in the fourth embodiment, and FIG. 20B is a diagram showing a surface light source device E7. It is a figure which shows the relationship between the position in the X direction of the center part in the Z direction, and the chromaticity of the light which illuminates the cover, FIG. 20C shows the position in the X direction of the center part in the Z direction in the surface light source device E7, and the emission. It is a figure which shows the relationship with the illumination intensity in the cover of the emitted light derived from each of the 1st, 2nd light emitting element from a part.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, embodiments of the present invention will be described in the form of a surface light source device as a representative example of the illumination device of the present invention.

[First Embodiment]
FIG. 1A is a plan view schematically showing the illumination device (surface light source device) according to the first embodiment of the present invention, and FIG. 1B is an enlarged view of a portion B in FIG. 1A. FIG. 1C is an enlarged view showing a main part of a cross section of the illumination device taken along line CC in FIG. 1A.

  The surface light source device 100 includes a substrate 110, a plurality of light emitting elements disposed on the substrate 110, a plurality of light flux control members 130 disposed at positions covering the light emitting elements on the substrate 110, and individual light flux control members. A plurality of light scattering members 140 disposed on the substrate 110, and a cover 150 disposed on the substrate 110 at a position away from the light flux controlling member 130.

  The substrate 110 is a member for supporting the light emitting element and the light flux controlling member 130. The substrate 110 may be a substrate normally used in a surface light source device, and includes a wiring for the light emitting element, a light diffusion layer for reflecting and diffusing incident light toward the cover 150, and the like. The substrate 110 supports the light emitting element and the light flux controlling member 130 at predetermined intervals in the X direction and the Z direction. The substrate 110 is made of a metal having high thermal conductivity such as aluminum or copper. In the case where the substrate 110 does not require high thermal conductivity, the substrate 110 can be made of a material having relatively low thermal conductivity such as a resin substrate obtained by impregnating a glass nonwoven fabric with an epoxy resin.

  The X direction is one direction in the plane direction of the substrate 110, the Y direction is a direction orthogonal to the plane direction, and the Z direction is a direction orthogonal to the X direction of the plane directions.

  On the substrate 110, a plurality of pairs of light emitting elements, each of which includes a first light emitting element 120a and a second light emitting element 120b, are arranged. For example, each of the first light emitting element 120a and the second light emitting element 120b is a light emitting diode (LED). The first light emitting element 120a and the second light emitting element 120b are arranged side by side in the X direction. Each of the first light emitting element 120a and the second light emitting element 120b has an optical axis along the Y direction.

  The first light emitting element 120a and the second light emitting element 120b emit light of different colors. Here, that the color of the emitted light is different means that the spectral distribution of the emitted light is different. Therefore, even if the emitted light has the same color, the color of the emitted light may be different. For example, the emission color of the first light emitting element 120a is magenta, and the emission color of the second light emitting element 120b is green.

  The light flux controlling member 130 and the light scattering member 140 will be described later.

  The cover 150 is a member that emits light emitted from the light flux controlling member 130, and usually has translucency and light diffusibility, and is also referred to as a diffusion member. The cover 150 is, for example, a resin flat plate, is opposed to the substrate 110, and is disposed away from any light flux controlling member 130 in the Y direction.

  Examples of the material of the cover 150 include a light transmissive resin such as polymethyl methacrylate (PMMA), polycarbonate (PC), polystyrene (PS), styrene / methyl methacrylate copolymer resin (MS), and a light transmissive resin. Glass. The light diffusibility of the cover 150 can be imparted to the cover 150 by a conventional method. For example, the cover 150 can be imparted by roughening the surface of the cover 150, or a scatterer such as a bead can be provided in the cover 150. It can be applied by dispersing.

  Next, the light flux controlling member 130 will be described. 2A is a perspective view from the front surface side of the light flux controlling member in the first embodiment, and FIG. 2B is a perspective view from the back surface side of the light flux controlling member. 3A is a front view of the light flux controlling member, FIG. 3B is a plan view of the light flux controlling member, FIG. 3C is a bottom view of the light flux controlling member, and FIG. 3D is the light flux controlling member. It is a side view of a control member. 4A is a view showing a cross section of the light flux controlling member taken along line AA in FIG. 3B, and FIG. 4B is a view showing a cross section of the light flux controlling member taken along line BB in FIG. 3B. is there.

  The light flux controlling member 130 is made of a translucent material. As the material, the resin material constituting the cover 150 described above can be used. The light flux controlling member 130 is, for example, an integrally molded product of such a resin. The light beam control member 130 may further have light diffusibility, and the light diffusibility can be imparted to the light beam control member 130 by the same method as that of the cover 150.

  The light flux controlling member 130 has a substantially rectangular plane shape that is long in the Z direction, and the shape of the surface side is confined at the center in the X direction and the Y direction. On the other hand, each has a line-symmetric shape. Moreover, the shape of the back surface side has a thick part in the substantially H shape of the center part in the Z direction and the both sides along the Z direction, and the other part is a thin part (concave part). A concave portion extending in the X direction is formed in the central portion in the Z direction of the central portion. The recess is formed in a position and size that covers the first light emitting element 120a and the second light emitting element 120b.

  The light flux controlling member 130 includes an incident part 131, a total reflection part, an emission part 138, and a light guide part 136.

  The incident part 131 is the surface of the recessed part formed in the thick part in the shape of the back surface side mentioned above. Thus, the incident part 131 is a part that covers the first light emitting element 120a and the second light emitting element 120b from the Y direction away from them, and receives the emitted light from the first light emitting element 120a and the second light emitting element 120b. Yes. A plane portion 133 is formed at the center of the incident portion 131 in the X direction and the Z direction, and a V-shaped groove 132 is formed adjacent to the plane portion 133 in the X direction. The plane portion 133 is formed in a range including the respective optical axes of the first light emitting element 120a and the second light emitting element 120b in the X direction (for example, between both optical axes), and is emitted from an emission unit 138 described later. Is formed to produce Thus, although the said center part in the incident part 131 is formed in the plane in this Embodiment, it is not restricted to it.

  The total reflection portion is a portion of a curved surface extending while expanding along the Z direction from the above-described constriction of the light flux controlling member 130, and is arranged on one side in the constricted Z direction. It includes a total reflection portion 135a and a second total reflection portion 135b disposed on the other side. The outer surfaces of the first total reflection part 135a and the second total reflection part 135b are both first light emitting element 120a and second light emitting element 120b in the Y direction and the X direction as they move away from the constriction along the Z direction. It is a convex curved surface having a shape in which the distance from is gradually increased. As described above, the total reflection part is configured to totally reflect a part of the light incident from the incident part 131 in the Z direction.

  The emission part 138 is formed in the constricted part of the light flux controlling member 130. Specifically, the emission part 138 is configured by a curved surface having a shape that is recessed in the Y direction with respect to the emission direction (outward) of the first light emitting element 120a and the second light emitting element 120b. More specifically, the emitting portion 138 is a concave curved surface portion that continuously connects the first total reflection portion 135a and the second total reflection portion 135b in the Z direction. The height of the emitting portion 138 (distance in the Y direction from the light emitting element) is constant in the X direction.

  The emission part 138 is disposed so as to intersect the optical axis of the first light emitting element 120a and the optical axis of the second light emitting element 120b in the X direction. For example, the emission part 138 is disposed at the center of the light flux controlling member 130 in the Z direction, and is disposed in the same range as the plane part 133 (that is, between both optical axes) in the X direction. As described above, the emission unit 138 is arranged at a position adjacent to the total reflection unit at the end near the optical axis (center side) of the total reflection unit in the Z direction, in addition to the light incident from the incident unit 131. Is configured to emit a part of the outside. That is, the emission part 138 may have any shape that emits the light reaching the emission part 138 outward, and is not limited to the shape in this embodiment.

  The light guide part 136 is a part that extends further outward along the Z direction from the total reflection part (a direction away from the optical axis of the first light emitting element 120a and the optical axis of the second light emitting element along the Z direction). is there. The light guide unit 136 has an outer surface and an inner surface whose shape when cut along the XY plane is substantially kamaboko. The outer surface has a tapered shape that slightly shrinks as it moves away from the total reflection portion along the Z direction. The inner surface has a substantially semi-cylindrical shape in the Z direction. Thus, the light guide 136 extends in the Z direction from the end of the total reflection part opposite to the optical axis in the Z direction, guides the incident light in the Z direction, and outwards from the light guide 136. It is comprised so that it may radiate | emit to.

  The above-mentioned constricted portion in the center in the Z direction of the light flux controlling member 130 is the convex curved surface of the first total reflection portion 135a and the convex curved surface of the second total reflection portion 135b opposite thereto, except for the above-described emission portion 138. It is comprised by the trough part formed between.

  Next, the light scattering member 140 will be described. FIG. 5A is a front view of the light scattering member in the present embodiment, FIG. 5B is a bottom view of the light scattering member, FIG. 5C is a side view of the light scattering member, and FIG. It is sectional drawing which follows the DD line in FIG. 5B of the said light-scattering member.

  The light scattering member 140 includes a main body 141 that covers the light flux controlling member 130, a diffuse transmission part 142 that is disposed at the center of the main body 141 in the Z direction, and a latch that is disposed at both ends of the main body 141 in the Z direction. It has a claw 143 and a projection 144 arranged at the center of the light scattering member 140 in the Z direction.

  The main body 141 is a semi-cylindrical member that covers most of the light flux controlling member 130 in the Z direction. The main body 141 only needs to have translucency, may be transparent, and may further have light diffusibility. The main body 141 can be made of the same material as the various materials described above for the cover 150 and the light flux controlling member 130.

  The diffuse transmission part 142 is composed of a plurality of parallel recesses 145 that extend along the X direction and are formed on the inner peripheral wall surface of the central part in the Z direction of the main body 141. The cross-sectional shape of each recess 145 in the YZ plane is, for example, a semicircular shape. The shape of the recess 145 may be the same or different.

  The locking claw 143 is a member for determining the position of the light scattering member 140 with respect to the light flux controlling member 130 and, for example, fits into a locking hole formed at both ends in the Z direction on the surface of the light flux controlling member 130. It is a member. Further, the protrusion 144 is a member for determining the position of the light scattering member 140 with respect to the substrate 110, for example, a member that fits into a positioning hole formed in the substrate 110.

  The light flux controlling member 130 is disposed at a position where the incident portion 131 covers the first light emitting element 120 a and the second light emitting element 120 b that are arranged in the X direction on the substrate 110. At this time, in the light flux controlling member 130, the optical axes of the first light emitting element 120 a and the second light emitting element 120 b are set at predetermined positions in the incident part 131 and the emission part 138, for example, the flat part 133 and the emission part in the incident part 131. 138 so as to intersect with 138.

  The light scattering member 140 is disposed so as to cover the light flux controlling member 130 disposed on the substrate 110 from the Y direction. The light scattering member 140 is disposed at a position determined with respect to one or both of the substrate 110 and the light flux control member 130, and the diffuse transmission portion 142 is disposed at a position covering the emission portion 138 of the light flux control member 130 in the Y direction. Is done.

  Thus, a light emitting device having the light emitting element and the light flux controlling member 130 is configured. Further, when the cover 150 is disposed on the substrate 110, an illumination device (surface light source device 100) is configured.

  The outgoing lights of the first light emitting element 120a and the second light emitting element 120b are incident on the light flux controlling member 130 from the incident part 131. Of the light incident on the incident portion 131, the light incident on the portion other than the plane portion 133 is basically totally reflected by the first total reflection portion 135 a or the second total reflection portion 135 b, and the light of the light guide portion 136. The light is emitted from the surface while being partially reflected on the surface. Thus, the light incident on the portion other than the flat portion 133 intersects in the X direction and the Y direction while being guided in the Z direction, and is emitted mainly from the light guide portion 136 outward.

  The light emitted from the light guide unit 136 is transmitted through the main body 141 of the light scattering member 140 in the portion where the light guide unit 136 is covered with the light scattering member 140, and mainly in the cover 150, the light flux control member 130. A region outside the portion corresponding to the central portion in the Z direction is illuminated uniformly. In other words, the area of the cover 150 corresponding to the light flux controlling member 130 and its periphery become the irradiation area by the light emitted from the light guide 136, but the brightness of the portion corresponding to the central portion in the Z direction of the light flux controlling member 130. Is supplemented by light other than the light emitted from the light guide unit 136. The magenta light of the first light emitting element 120a and the green light of the second light emitting element 120b are mixed toward the portions corresponding to both ends in the Z direction of the light flux controlling member 130 in the cover 150, and are emitted from the light guide 136. Is observed as white light.

  Of the light incident on the incident portion 131, a part of the light incident on the plane portion 133 is emitted from the emitting portion 138. The light emitted from the light emitting portion 138 is transmitted and diffused through the diffusing and transmitting portion 142 of the light scattering member 140 and reaches a portion of the cover 150 corresponding to the central portion in the Z direction of the light flux controlling member 130. The light emitted from the emission part 138 through the flat part 133 will be further described.

  FIG. 6A is a diagram schematically illustrating the positional relationship between the light flux controlling member and the light emitting element for the purpose of explanation, and FIG. 6B is an emission angle of the emitted light on the XY plane from the light emitting element. It is a figure for demonstrating. As shown in FIG. 6A, the planar shape of the light emitting element is a square, and the center thereof is on the central axis along the X direction passing through the center in the Z direction of the light flux controlling member 130. The optical axis of the light emitting element represents the optical center of the light emitted from the light emitting element, and is represented by a straight line passing through the center of the planar shape of the light emitting element along the Y direction. In FIG. 6B, OA1 represents the optical axis of the first light emitting element 120a, and OA2 represents the optical axis of the second light emitting element 120b. Of the X directions on the XY plane, the first light emitting element 120a side is defined as the X1 direction, and the second light emitting element 120b side is defined as the X2 direction.

  With respect to the light emitted from the emitting portion 138, in the X direction, the light from the center of one light emitting element exceeds the light from the inner edge of the other light emitting element (the edge on the one light emitting element side) and farther away. To reach. That is, the intersection of the first light emitting element 120a and its optical axis OA1 is A1, the end of the second light emitting element 120b on the X1 direction side is A2, and the portion of the emission portion 138 through which the emitted light from the first light emitting element 120a passes , The X2 direction end is B1, and the X2 direction end of the portion where the emission light of the second light emitting element 120b in the emission part 138 passes is B2, and the intersection with the cover 150 of the straight line L1 passing A1 and B1 Is C1 (not shown), and C1 is located on the X2 direction side (direction away from the optical axis OA2) from C2 when the intersection of the straight line L2 passing through A2 and B2 with the cover 150 is C2. . B1 and B2 overlap.

  Thus, when viewed from the X2 side, the light from the center of the farther first light emitting element 120a is farther away than the light from the inner edge (edge on the X1 direction side) of the closer second light emitting element 120b. Has reached. Although not shown, similarly, on the X1 side, light from the center of the second light emitting element 120b reaches farther than light from the inner edge (edge on the X2 direction side) of the first light emitting element 120a. Therefore, the emitted light emitted from the emitting part 138 from each of the first light emitting element 120a and the second light emitting element 120b overlaps with each other on the inner surface of the cover 150 with certainty.

  Further, with respect to the light emitted from the emitting portion 138, in the X direction, the ratio of the light intensity of one light emitting element to the light intensity of the other light emitting element is between specific positions on the inner surface of the cover 150. It is preferable that it is in a certain range from the viewpoint of improving the uniformity of the color mixture of light from both light emitting elements.

  That is, the intersection point between the optical axis OA1 of the first light emitting element 120a and the cover 150 is C3, the intersection point between the second light emitting element 120b and the optical axis OA2 is A3, and the end of the emitting portion 138 on the X1 direction side is B3, A1 and Let the intersection of the straight line (P3) passing through B3 and the cover 150 be C4. A straight line connecting A1 and C3 is P1, a straight line connecting A3 and C3 is P2, a straight line connecting A1 and C4 is P3, and a straight line connecting A3 and C4 is P4. Further, the luminous intensity of light from the first light emitting element 120a going from A1 to C3 (along the straight line P1) is I1, and the luminous intensity of light from the second light emitting element 120b going from A3 to C3 (along the straight line P2) is I2. The ratio I1 / I2 is IA, the luminous intensity of light from the first light emitting element 120a going from A1 to C4 is I3, and the luminous intensity of light from the second light emitting element 120b going from A3 to C4 is I4. When I3 / I4 is IB, it is preferable from the above viewpoint that IA is 0.9 to 1.1 times IB.

  Thus, when viewed from the X1 side, the ratio of the light intensity of the light emitted from the closer first light emitting element 120a to the light intensity of the light emitted from the farther second light emitting element 120b is closer to the first light emitting element 120a. It is substantially equal in a particular range of ranges in the X direction that light from the center reaches. Although not shown, similarly, when viewed from the X2 side, the ratio of the light intensity of the light emitted from the closer second light emitting element 120b to the light intensity of the light emitted from the farther first light emitting element 120a is closer to the second light emission. It is substantially equal in a specific range of the range in the X direction where the light from the center of the element 120b reaches.

  When the relationship between IA and IB is satisfied, the chromaticity difference in the overlapping portion of the light emitted from the first light emitting element 120a and the light emitted from the second light emitting element 120b in the cover 150 is sufficiently small, and color unevenness is caused. Virtually no longer observed. Thus, it is preferable that the above relationship is satisfied from the viewpoint of improving the uniformity of the color mixture of light in the cover 150.

  As is clear from the above description, the emitted light from the emitting portion 138 reaches the portion corresponding to the central portion in the Z direction of the light flux controlling member 130 in the cover 150 and is emitted from the other portion of the light flux controlling member 130. It is observed as white light in the same way as incident light. Accordingly, the cover 150 uniformly emits white light outward without forming a dark part in both the X direction and the Z direction.

  The positional relationship between C1 and C2 in the X direction and the relationship between IA and IB are as follows: the distance between the light emitting elements in the X direction, the length of the emitting portion 138 in the X direction, the X of the plane portion 133 It is possible to adjust by the length in the direction, or the optical distance. The optical distance is a distance from the light source to the irradiated surface. For example, in the surface light source device 100, the distance from the light emitting element installation surface to the inner surface of the cover 150 in the Y direction. For example, the optical distance can be appropriately determined from a range of 10 to 30 mm. The above-mentioned distance, length and optical distance are appropriately predicted and confirmed by one or both of simulation by a computer (for example, using a general-purpose PC and a known program for optical design) and actual measurement by a prototype. It is possible.

  FIG. 7A is a diagram schematically showing a light emitting element and a light flux controlling member in a surface light source device (herein also referred to as “surface light source device E1”) having the same configuration as that of the surface light source device 100, and FIG. It is a figure which shows the relationship between the position in the X direction of the center part in the Z direction of the said light beam control member of the said light source device E1, and the chromaticity of the light which illuminates a cover, FIG. 7C is the said light beam control of the surface light source device E1. It is a figure which shows the relationship between the position in the X direction of the center part in the Z direction of a member, and the illumination intensity in the cover of the emitted light derived from each of the 1st, 2nd light emitting element from an output part. The illuminance is expressed as a ratio when the maximum illuminance is 1.

  In FIG. 7A, the length of each light emitting element in the X direction is 2.5 mm, the pitch between the light emitting elements (the distance between the centers of both light emitting elements in the X direction) is 7 mm, and the optical distance OD is 20 mm. Both the length in the X direction of the plane portion and the emission portion are 7 mm, and both ends thereof are in contact with the optical axes OA1 and OA2. In FIG. 7B, dx represents the distance (mm) from the center in the X direction of the light flux controlling member E1, and the first light emitting element (X1 direction) side is positive and the second light emitting element (X2 direction) side from the center. Expressed negative. In FIG. 7C, Er represents the ratio of the illuminance to the maximum illuminance at the cover (irradiated surface) of the emitted light of each light emitting element. The broken line represents the illuminance ratio of the emitted light (magenta light) of the first light emitting element, and the solid line represents the illuminance ratio of the emitted light (green light) of the second light emitting element.

  In addition, the relationship between the emission angle of the emitted light of the 1st light emitting element and the 2nd light emitting element, and the luminous intensity is shown in FIG. The angle of the emission angle is displayed with the first light emitting element side being positive and the second light emitting element side being negative. In the light flux controlling member of the surface light source device E1, the distance between the optical axes OA1 and OA2, the length of the emitting portion, and the length of the flat portion are all the same. For this reason, in the above-mentioned C2, C1 is clearly on the X2 direction side than C2. Moreover, the above-mentioned C3 and C4 overlap. Therefore, the above IA and IB are also equal, and the ratio thereof is 1. Therefore, as shown in FIG. 7B, the difference in chromaticity u ′ in the X direction is sufficiently small. At this time, the illuminance of the light of each light emitting element in the cover exhibits a distribution having a peak slightly far from the center in the X direction. In the case of such an illuminance distribution, it can be seen that the light reaching the cover from the emitting portion appears to be sufficiently mixed in color.

  FIG. 9A is a diagram schematically showing an emission angle of the emitted light of the light emitting element in the light flux control member of the surface light source device E2, and FIG. 9B is a diagram of the surface light source device E2 in the Z direction of the light flux control member. 9C is a diagram showing the relationship between the position of the central portion in the X direction and the chromaticity of light that illuminates the cover, and FIG. 9C shows the position of the central portion in the Z direction of the light flux controlling member of the surface light source device E2 in the X direction. It is a figure which shows the relationship with the illumination intensity in the cover of the emitted light derived from each of the 1st, 2nd light emitting element from an emission part.

  The surface light source device E2 is configured in the same manner as the surface light source device E1 except that the length of the plane portion and the emission portion in the X direction is longer. More specifically, the lengths of the emission part and the plane part are both the length of the emission part when the end of the emission part is in contact with a straight line having a predetermined angle φ1 (= 10 °) with respect to the optical axis. The same.

  In the light flux controlling member of the surface light source device E2, the length of the emitting portion and the length of the flat portion are both longer than the distance between the optical axes OA1 and OA2, but the above-mentioned C1 is on the X2 direction side with respect to C2. It is clear. The above-mentioned C4 is located outside C3, but the difference is 10 °. According to FIG. 8, the light intensity of 10 ° in each light emitting element has almost no difference with respect to the peak value of light intensity, and thus the ratio of IA and IB is approximately 1. Therefore, as shown in FIG. 9B, the difference in chromaticity u ′ in the X direction is sufficiently small. At this time, the illuminance of the light of each light emitting element in the cover has a peak at substantially the center in the X direction, but the skirt has a distribution slightly shifted far away. It can be seen that even in such an illuminance distribution, the light reaching the cover from the emitting portion appears to be sufficiently mixed in color.

  In the surface light source devices E1 and E2, the cover is illuminated with white light in which two colors of light from the light emitting elements are appropriately mixed. Therefore, the white light is emitted from the cover, and both the surface light source devices E1 and E2 function as an illumination device that emits white light in a planar shape.

  FIG. 10A is a diagram schematically illustrating an emission angle of light emitted from the light emitting element in the light beam control member of the surface light source device C1, and FIG. 10B is a diagram illustrating the center of the surface light source device C1 in the Z direction of the light beam control member. 10C is a diagram showing the relationship between the position in the X direction and the chromaticity of the light that illuminates the cover, and FIG. 10C shows the position in the X direction of the central portion in the Z direction of the light flux controlling member of the surface light source device C1; It is a figure which shows the relationship with the illumination intensity in the cover of the emitted light derived from each of the 1st, 2nd light emitting element from an output part. The surface light source device C1 is configured in the same manner as the surface light source device E1 except that the light flux controlling member does not have a flat surface portion and an emission portion.

  As shown in FIG. 10A, in the surface light source device C1, the light emitted in all directions from each of the first and second light emitting elements is mainly guided in the Z direction in the total reflection portion, but the remaining light is The light distribution in the X direction is emitted from a slight valley between the total reflection portions without being controlled.

  Since the light emitted from the first light emitting element and the second light emitting element are not restricted in the X direction, the light emitted from the first light emitting element is farther in the X1 direction than the light emitted from the second light emitting element. The light emitted from the second light emitting element reaches farther in the X2 direction than the light emitted from the first light emitting element. That is, in the surface light source device C1, the aforementioned point C2 on the inner surface of the cover is farther than C1, and C3 exists but C4 does not exist.

  In the surface light source device C1, as shown in FIG. 10B and FIG. 10C, the light emitted from the first light emitting element has a stronger influence on the first light emitting element side than the center of the light flux controlling member, and is more than the center of the light flux controlling member. On the second light emitting element side, the light emitted from the second light emitting element has a stronger influence. As a result, the cover is illuminated by each of the two colors of light from the light emitting element, and the color unevenness due to the two colors of light occurs in the cover at a portion corresponding to the central portion in the Z direction of the light flux controlling member. To do.

  FIG. 11A is a diagram schematically illustrating an emission angle of light emitted from the light emitting element and the light flux control member in the surface light source device E3, and FIG. 11B illustrates a central portion in the Z direction of the light flux control member in the surface light source device E3. It is a figure which shows the relationship between the position in X direction, and the chromaticity of the light which illuminates a cover, and FIG. 11C shows the position in the X direction of the center part in the Z direction of the said light beam control member in the surface light source device E3, and an output part. It is a figure which shows the relationship with the illumination intensity in the cover of the emitted light originating in each of the 1st, 2nd light emitting element.

  The surface light source device E3 is configured in the same manner as the surface light source device E1 except that the length of the flat portion and the emitting portion in the X direction is longer. More specifically, the lengths of the emission part and the plane part are both the length of the emission part when the end of the emission part is in contact with a straight line having a predetermined angle φ2 (= 20 °) with respect to the optical axis. The same.

  In the light flux controlling member of the surface light source device E3, the length of the emitting portion and the length of the flat portion are both longer than the distance between the optical axes OA1 and OA2, but the above-mentioned C1 is on the X2 direction side with respect to C2. It is clear. The aforementioned C4 is located outside C3, and the difference is 20 °. According to FIG. 8, the luminous intensity of 20 ° in each light emitting element has a difference with respect to the peak value of luminous intensity.

  In the surface light source device E3, as shown in FIG. 11B, the chromaticity u ′ slightly increases or decreases in the X direction, but the difference in the chromaticity u ′ in the X direction is sufficiently small. However, with respect to the center in the X direction, the illuminance of the light of the first light emitting element is shifted to the X1 direction side, and the illuminance of the light of the second light emitting element is shifted to the X2 direction side. Therefore, it can be seen that in the surface light source device E3, it appears that there is some color unevenness in the portion corresponding to the emitting portion in the cover.

  As is clear from the above description, the illumination device according to the present embodiment is arranged side by side in the X direction, the light emission colors thereof are different from each other, and the optical axis OA1 along the Y direction orthogonal to the X direction, First light emitting element 120a and second light emitting element 120b each having OA2, light flux controlling member 130 covering first light emitting element 120a and second light emitting element 120b from the Y direction, and position away from light flux controlling member 130 in the Y direction And a cover 150 disposed on the surface. The light flux controlling member 130 covers the first light emitting element 120a and the second light emitting element 120b from the Y direction away from them, and receives an incident part 131 that receives the emitted light from the first light emitting element 120a and the second light emitting element 120b, and an incident part The first light emitting element 120a and the second light emitting element 120a and the second light emitting element 120a are configured to totally reflect a part of the light incident from 131 toward the Z direction orthogonal to the X direction and the Y direction, and the total reflection part in the Z direction. The light emitting element 120b is disposed at a position adjacent to the ends on the optical axes OA1 and OA2 side, and an emission part 138 for emitting another part of the light incident from the incident part 131 outward, and the total reflection part Extending in the Z direction from the end opposite to the optical axes OA1 and OA2 in the Z direction, the incident light is guided in the Z direction and emitted to the X and Y directions, that is, to the outside of the light flux controlling member 130. And a light guide portion 136 for. In the XY plane including the X direction and the Y direction (cross section including the optical axes OA1 and OA2), the intersection of one light emitting element of the first light emitting element 120a and the second light emitting element 120b and the optical axis is A1, Of the other light-emitting element of the first light-emitting element 120a and the second light-emitting element 120b, the end on the one element side in the X direction is A2, and X of the part through which the emitted light of the one light-emitting element passes in the emission part 138 B1 is the end on the other light emitting element side in the direction, and B2 is the end opposite to the one light emitting element in the X direction in the portion of the emitting portion 138 through which the emitted light from the other light emitting element passes. When C1 is the intersection of the straight cover 150 passing through B1 and B1, and C2 is the intersection of the straight cover 150 passing through A2 and B2, C1 is more in the X direction than C2. Kicking located on the outside. In the present embodiment, the above B2 overlaps with B1. With the above-described configuration, the lighting device can achieve uniform light emission without the need for individual adjustment of the light emitting elements in light emission due to the color mixture of a plurality of light emitting elements.

  In the illuminating device, the number of the emitting portions 138 can be one per light flux controlling member 130, and the number of the incident portions 131 can be one per light flux controlling member 130.

  In addition, the fact that the emission part 138 is formed of a concave curved surface that is recessed in the light emission direction constitutes the emission part 138 with the total reflection parts as continuous connection parts, and is a discontinuous connection part. This is more effective from the viewpoint of preventing defective light emission such as bright lines and dark lines in the cover 150 caused by the above.

  In addition, it is more effective that the illumination device further includes the light scattering member 140 that covers the emission part 138 from the Y direction from the viewpoint of improving the light intensity and color uniformity in the cover 150.

  Further, in the XY plane, the intersection of the optical axis of the one light emitting element and the cover 150 is C3, the intersection of the other light emitting element and the optical axis is A3, and the emitted light of the one light emitting element in the emission unit 138 Of the X-direction side in the X direction of the portion through which the straight line passes through B3, A1 and B3 and the intersection of the cover 150 with C4, the light intensity I1 of the light from the one light emitting element heading from A1 to C3 The ratio I1 / I2 to the luminous intensity I2 of the light from the other light emitting element going from A3 to C3 is IA, and the luminous intensity I3 of the light from the one light emitting element going from A1 to C4 is directed from A3 to C4. When the ratio I3 / I4 to the light intensity I4 of the light from the other light emitting element is IB, IA is 0.9 to 1.1 times IB. It shines light is more effective in terms of suppressing the color unevenness of the portion to reach.

  Further, in the light flux controlling member 130, there is only one emitting portion 138 and one incident portion 131, and the positions of both ends of the emitting portion 138 in the X direction are the optical axes OA1 of the first light emitting element 120a and the second light emitting element 120b. If the position is OA2 or more, the C1 can be positioned on the outer side in the X direction than the C2, regardless of the length of the optical distance.

[Second Embodiment]
The illumination device according to the second embodiment of the present invention is substantially the same as the first embodiment described above except that it has a light beam control member 230 instead of the light beam control member 130. Hereinafter, the light flux controlling member 230 will be described.

  FIG. 12A is a perspective view from the front surface side of the light flux controlling member in the second embodiment, and FIG. 12B is a perspective view from the back surface side of the light flux controlling member. 13A is a front view of the light flux controlling member, FIG. 13B is a plan view of the light flux controlling member, FIG. 13C is a bottom view of the light flux controlling member, and FIG. 13D is the light flux controlling member. It is a side view of a control member. 14A is a view showing a cross section of the light flux controlling member taken along line AA in FIG. 13B, and FIG. 14B is a view showing a cross section of the light flux controlling member taken along line BB in FIG. 13B. is there.

  The light flux controlling member 230 includes a first incident portion 231a, a second incident portion 231b, a first total reflection portion 235a, a second total reflection portion 235b, a first emission portion 238a, a second emission portion 238b, and a light guide portion 236. Have.

  Both the first incident portion 231 a and the second incident portion 231 b are concave portions formed in the central portion in the Z direction of the bottom surface of the light flux controlling member 230. The first incident portion 231a is disposed on the X1 direction side in the X direction of the central portion, and the second incident portion 231b is disposed on the X2 direction side. The planar shape of the opening of the first incident portion 231a is a hexagon. A V-shaped groove 232 is formed on the diagonal line of the first incident portion 231a opposite to the X direction in the hexagon. The second incident portion 231b is configured similarly to the first incident portion 231a.

  The first total reflection portion 235a is disposed on one side of the center of the light flux controlling member 230 in the Z direction, and the second total reflection portion 235b is disposed on the other side. In any case, the total reflection portion has a shape in which the distance to the light emitting element in the Y direction gradually increases as the distance from the light emitting element increases toward one or the other in the Z direction, and the YZ plane passes through the center in the X direction. It has a plane-symmetric shape, and has a trough formed at the boundary between two convex curved surfaces at the center. More specifically, each of the total reflection portions has a shape in which the centers of two hemispherical surfaces arranged in parallel are brought close to each other at a distance less than the radius and combined. Both total reflection parts are connected in the Z direction, and a trough is formed at the boundary.

  Each of the first emission part 238a and the second emission part 238b is independently arranged so as to protrude from a trough at the boundary (along the X direction) of the first total reflection part 235a and the second total reflection part 235b. ing. More specifically, each of the emission portions is a mountain-shaped section formed by a YZ plane formed by a top edge along the boundary and slopes inclined from the top edge to both sides in the Z direction. . However, in the XY plane, the first emission part 238a is arranged so that the center in the X direction is located on the X2 direction side of the optical axis OA1 of the first light emitting element 120a, and the second emission part 238b is The center in the X direction is arranged so as to be located on the X1 direction side with respect to the optical axis OA2 of the second light emitting element 120b.

  The light guide portion 236 is a portion extending along the Z direction from each of the total reflection portions. Each of the light guide portions 236 has a cylindrical outer surface and an inner surface that is a shallow recess having a length in the Y direction that is shorter than the length in the X direction on the XY plane. More specifically, the outer surface has such a shape that the central axes of two parallel semicircular bodies are brought close to each other at a distance less than the radius thereof, and the boundary of the combined semicylindrical bodies It has the trough part formed.

  The light flux controlling member 230 further includes a protrusion 239 that protrudes from the side edge in the X direction toward the Y direction (on the opposite side to the emitting portion). The protrusion 239 is a member for determining the position of the light flux controlling member 230 with respect to the substrate 110, for example, a member that fits into a positioning hole formed in the substrate 110.

  The light flux controlling member 230 includes the first light emitting element 120a and the first light emitting element 120a of the second light emitting element 120b arranged side by side in the X direction on the substrate 110 as the first incident portion 231a and the second light emitting element 120b as the first light emitting element 120b. It arrange | positions in the position which each covers with 2 incident part 231b. On the light flux controlling member 230, the light scattering member 140 is disposed at a position where the diffuse transmitting portion 142 covers both the first light emitting portion 238a and the second light emitting portion 238b of the light flux controlling member 230, and further on the substrate 110. The cover 150 is disposed on the illuminating device (surface light source device).

  The light emitted from each of the first light emitting element 120a and the second light emitting element 120b is incident on the light flux controlling member 230 from the first incident part 231a and the second incident part 231b. Of the light incident on the first incident portion 231a and the second incident portion 231b, the light incident on the portion other than the portion corresponding to the first exit portion 238a and the second exit portion 238b is basically the first total reflection. The light is totally reflected by the portion 235a or the second total reflection portion 235b, and is emitted from the surface of the light guide portion 236 while being partially reflected on the surface.

  Thus, the light incident on the part other than the part corresponding to the emitting part is guided in the Z direction, intersects the X direction and the Y direction, and is emitted mainly from the light guiding part 236 to the outside. The light is transmitted through the main body 141, and the region outside the portion of the cover 150 corresponding to the central portion in the Z direction of the light flux controlling member 230 is uniformly illuminated, and is observed as white light.

  On the other hand, magenta light of the first light emitting element 120a is emitted from the first light emitting element 238a among the light incident on the part corresponding to the light emitting part in the light incident part, and the green light of the second light emitting element 120b is The light is emitted from the second emission part 238b. The emitted light from these emission parts is transmitted and diffused through the diffusion transmission part 142 of the light scattering member 140, and reaches a part of the cover 150 corresponding to the central part in the Z direction of the light flux control member 130.

  FIG. 15A is a diagram schematically illustrating an emission angle of light emitted from the light emitting element and the light flux controlling member in the surface light source device of the present embodiment, and FIG. 15B illustrates a single surface light source device (“surface light source” in the present embodiment. (Also referred to as “device E4”) The relationship between the position in the X direction of the central portion of the light flux controlling member in the Z direction and the illuminance on the cover of the emitted light derived from each of the first and second light emitting elements from the emitting portion. FIG. FIG. 15C shows the position in the X direction of the central portion in the Z direction of the light flux controlling member in the other surface light source device (also referred to as “surface light source device E5”) in the present embodiment, and the first and first positions from the emitting portion. It is a figure which shows the relationship with the illumination intensity in the cover of the emitted light originating in each of 2 light emitting elements.

  In the surface light source device E4, one end on the outer side (X1 direction side) in the X direction of the first emitting portion 238a passes through the light emission center of the first light emitting element 120a and is a straight line representing an angle of 10 ° outward with respect to the optical axis OA1. It is in a position that overlaps. In addition, one end on the inner side (X2 direction side) in the X direction of the first emitting portion 238a passes through the light emission center of the first light emitting element 120a and is at a position where a straight line representing an angle of 30 ° overlaps the optical axis OA1. is there. Similarly, one end on the inner side (X1 direction side) in the X direction of the second emission part 238b overlaps with a straight line that passes through the emission center of the second light emitting element 120b and represents an emission angle of 30 ° inward with respect to the light source OA2. One end on the outer side (X2 direction side) passes through the light emission center of the second light emitting element 120b and overlaps with a straight line representing an emission angle of 10 ° outward with respect to the optical axis OA2.

  Further, the cover of the surface light source device E4 is disposed at a position having a sufficiently long optical distance (for example, 20 mm) in the Y direction. Therefore, an unillustrated intersection C1 between the straight line L1 passing through A1 and B1 and the cover in FIG. 15A and an unillustrated intersection C2 between the straight line L2 passing through A2 and B2 and the cover is outside of the X direction (X2). Located on the direction side). Further, although the above-mentioned C4 in the surface light source device E4 is located outside C3, the difference is 10 °. Therefore, the ratio of IA and IB in the surface light source device E4 is the same as that of the surface light source device E2. Similarly, it is almost 1. Therefore, the difference in chromaticity u ′ in the X direction is sufficiently small, and as shown in FIG. 15B, the illuminance of light of each light emitting element in the cover has a distribution having a peak slightly far from the center in the X direction. Presents.

  The surface light source device E5 is configured in the same manner as the surface light source device E4, except that the inner ends in the X direction of both emission portions are located at positions where straight lines representing an angle of 35 ° overlap with the respective optical axes. ing. Also in the surface light source device E5, C1 is located on the outer side in the X direction with respect to C2, and C4 is located on the outer side with respect to C3. However, the light intensity ratios in C3 and C4 can be regarded as almost the same. The ratio of IB and IB is approximately 1. Therefore, the difference in chromaticity u ′ in the X direction is sufficiently small, and as shown in FIG. 15C, the illuminance of light of each light emitting element in the cover has a distribution having a peak slightly far from the center in the X direction. Presents.

  Therefore, in any of the surface light source devices E4 and E5, the cover is illuminated with white light in which two colors of light from the light emitting elements are appropriately mixed. Therefore, the white light is emitted from the cover, and both the surface light source devices E4 and E5 function as an illumination device that emits white light in a planar shape.

  As is clear from the above description, in the illumination device of the present embodiment, the emission unit emits the first emission unit for emitting the emission light of the first light emitting element and the emission light of the second light emission element. A first emitting part for receiving light emitted from the first light emitting element, and a second incident part for receiving emitted light from the second light emitting element. This has substantially the same configuration as the illumination device of the embodiment. Therefore, similarly to the illumination device according to the first embodiment, the illumination device of the present embodiment can perform uniform surface light emission without requiring individual adjustment of the light emitting elements.

[Third Embodiment]
The illuminating device in the third embodiment of the present invention is substantially the same as the first embodiment described above except that it has a light flux control member 330 instead of the light flux control member 130. Hereinafter, the light flux controlling member 330 will be described.

  FIG. 16A is a perspective view from the front surface side of the light flux controlling member in the third embodiment, and FIG. 16B is a perspective view from the back surface side of the light flux controlling member. 17A is a bottom view of the light flux controlling member, FIG. 17B is a view showing a cross section of the light flux controlling member taken along line BB in FIG. 17A, and FIG. 17B is a diagram of the light flux controlling member. It is a figure which shows the cross section which follows the CC line in FIG. 17A.

  The light flux controlling member 330 is configured in the same manner as the light flux controlling member 130 except that the light flux controlling member 330 has a first incident portion 331a and a second incident portion 331b instead of the incident portion 131. The first incident portion 331a includes a predetermined position in the X direction, for example, a first incident surface portion 333a formed on the inner side (X2 direction side) from the center in the X direction of the first incident portion 331a, and the outer side (X1 direction side). It is comprised similarly to the 1st incident part 231a in 2nd Embodiment except including the V-shaped groove | channel 332 formed in this. Similarly, the second incident portion 331b is, for example, a second incident surface portion 333b formed on the inner side (X1 direction side) from the center in the X direction, and a V-shaped groove 332 formed on the outer side (X2 direction side). The configuration is the same as that of the second incident portion 231b in the second embodiment except that the second incident portion 231b is included. The emission part is configured the same as that of the first light flux controlling member 130.

  The first incident surface portion 333a and the second incident surface portion 333b are portions in which the V-shaped groove 332 is filled with the above-described resin material, and the surfaces of the first incident surface portion 333a and the second incident surface portion 333b are opposite sides of the V-shaped groove 332 in the YZ plane. This is the part represented by a straight line. The first incident surface portion 333 a and the second incident surface portion 333 b have the same function as the flat surface portion 133 of the light flux controlling member 130.

  FIG. 18 is a diagram schematically illustrating the emission angle of the emitted light from the light emitting element in the light flux controlling member 330. In the light beam control member 330, B <b> 1 and B <b> 2 described above overlap as in the light beam control member 130. In the illumination device of the present embodiment, the intersection C1 (not shown) between the straight line L1 and the cover in FIG. 18 is more outward in the X direction (X2 direction side) than the intersection C2 (not shown) between the straight line L2 and the cover. To position. Further, in the illumination device of the present embodiment, since the above-described C3 and C4 overlap as in the above-described surface light source device E1, the above-described IA and IB are equal, and the ratio thereof is 1.

  Therefore, similarly to the surface light source device E1, the illumination device of the present embodiment exhibits chromaticity u ′ having a sufficiently small difference in the X direction as shown in FIG. 7B, and the light of each light emitting element in the cover. The illuminance of has a distribution having a peak slightly far from the center in the X direction. And also in the illuminating device of this Embodiment, a cover is illuminated by the white light which two colors of light from a light emitting element mixed appropriately. Therefore, the white light is emitted from the cover, and the illumination device functions as an illumination device that emits white light in a planar shape.

  The illumination device in the present embodiment can also satisfy the conditions of the emitted light and the luminous intensity described in the first embodiment, and, similarly to the illumination devices according to the first and second embodiments, a light emitting element Therefore, uniform surface light emission is possible without the need for individual adjustment.

[Fourth Embodiment]
The illumination device according to the fourth embodiment of the present invention is substantially the same as the first embodiment described above except that the light beam control member 430 is provided instead of the light beam control member 130. The light flux controlling member 430 has a first emitting part 438a and a second emitting part 438b instead of the emitting part 138, and the incident part includes a first flat part 433a and a second flat part 433b corresponding thereto. The light beam control member 130 is configured in the same manner.

  For example, the first emission part 438a and the second emission part 438b are formed by forming a trough in the central part of the emission part 138, so that the first light emitting element 120a side (that is, the first emission part 438a) and the second light emitting element are formed. It has the same configuration as that of the case where it is divided into the portion on the 120b side (that is, the second emitting portion 438b). The first flat surface portion 433a and the second flat surface portion 433b also have the same configuration as the case where the flat surface portion is divided by forming a V-shaped groove in the central portion of the flat surface portion 133.

  The first emitting portion 438a is disposed at a position where the end of the first emitting portion 438a overlaps with the optical axis OA1 of the first light emitting element and a straight line having an angle of 30 ° inward with respect to the optical axis OA1 in the X direction. . The second emission part 438b is disposed at a position where the end thereof overlaps with the optical axis OA2 of the second light emitting element and a straight line forming an angle of 30 ° inward with respect to the optical axis OA2 in the X direction. . The first flat surface portion 433a is disposed at a position overlapping the first light emitting portion 438a in the Y direction, and the second flat surface portion 433b is disposed at a position overlapping the second light emitting portion 438b in the Y direction.

  FIG. 19A is a diagram schematically showing an emission angle of light emitted from the light emitting element and the light flux controlling member in one illumination device (also referred to as “surface light source device E6”) in the present embodiment, and FIG. It is a figure which shows the relationship between the position in the X direction of the center part in the Z direction of the light beam control member in the apparatus E6, and the chromaticity of the light which illuminates the cover, FIG. 19C is X of the center part in the Z direction of the surface light source device E6. It is a figure which shows the relationship between the position in a direction, and the illumination intensity in the cover of the emitted light derived from each of the 1st, 2nd light emitting element from an output part.

  In the surface light source device E6, similarly to the surface light source device E1, the above-described C3 and C4 overlap, so that the above-described IA and IB are equal, and the ratio thereof is 1.

  Therefore, similarly to the surface light source device E1, the surface light source device E6 exhibits a chromaticity u ′ whose difference in the X direction is sufficiently small as shown in FIG. 19B, and each of the covers as shown in FIG. 19C. The illuminance of light of the light emitting element exhibits a distribution having a peak slightly far from the center in the X direction. In the surface light source device E6, the cover is illuminated with white light in which two colors of light from the light emitting elements are appropriately mixed. Therefore, the white light is emitted from the cover, and the surface light source device E6 functions as an illumination device that emits white light in a planar shape.

  FIG. 20A is a diagram schematically showing an emission angle of emitted light of a light emitting element and a light flux controlling member in another illumination device (also referred to as “surface light source device E7”) of the present embodiment, and FIG. It is a figure which shows the relationship between the position in the X direction of the center part in the Z direction of the light beam control member in the light source device E7, and the chromaticity of the light which illuminates the cover, and FIG. 20C shows the Z direction of the light beam control member in the surface light source device E7. It is a figure which shows the relationship between the position in the X direction of the center part, and the illumination intensity in the cover of the emitted light derived from each of the 1st, 2nd light emitting element from an output part.

  In the surface light source device E7, the position and the size in the X direction of the first emission part 438a, the second emission part 438b, the first plane part 433a, and the second plane part 433b in the light flux controlling member 430 are the same as those in the surface light source apparatus E6. Except for these differences, the configuration is the same as that of the surface light source device E6.

  In the surface light source device E7, the first emitting portion 438a has an end that extends in the X direction through the light emission center of the first light emitting element and forms an angle of about 10 ° outward with respect to the optical axis OA1. It is arranged at a position overlapping with a straight line forming an angle of about 40 °. The second emitting portion 438b has a straight line whose end passes through the light emission center of the second light emitting element in the X direction and forms an angle of 10 ° on the outside with respect to the optical axis OA2, and a straight line that forms an angle of 40 ° on the inside. It is arranged at the position that overlaps. The first flat surface portion 433a is disposed at a position overlapping the first light emitting portion 438a in the Y direction, and the second flat surface portion 433b is disposed at a position overlapping the second light emitting portion 438b in the Y direction.

  Also in the surface light source device E7, the aforementioned C1 is located on the X2 direction side with respect to C2. In the surface light source device E7, as in the surface light source device E2, the above-mentioned C4 is located outside C3. However, the straight line connecting C3 and the light emission center of the first light emitting element, and C4 and the first light emitting element. Since the angle formed with the straight line connecting the emission center is 10 °, the ratio of IA and IB is approximately 1. Therefore, as shown in FIG. 20B, the difference in chromaticity u ′ in the X direction is sufficiently small. In addition, as shown in FIG. 20C, the illuminance of light of each light-emitting element has a distribution with a peak at a substantial center in the X direction, but its base is slightly shifted far away.

  Therefore, also in the surface light source device E7, the cover is illuminated with white light in which two colors of light from the light emitting elements are appropriately mixed, and the white light is emitted from the cover. Thus, the surface light source device E7 also functions as an illumination device that emits white light in a planar shape.

  As is clear from the above description, the illumination device in the present embodiment has a configuration in which the incident portion and the emission portion are substantially independent corresponding to the light emitting elements. In this way, the incident part and the emission part may be configured substantially independently corresponding to the light emitting elements, and the incident part covers both the first light emitting element and the second light emitting element from the viewpoint of mold manufacture and molding. You may comprise as one dent.

[Other embodiments]
In the above-described embodiment, the first light-emitting element and the second light-emitting element are elements that emit two colors of light that exhibit white color by mixing colors, but the emission colors of both light-emitting elements are other than white by color mixing. It is also possible to appropriately select from combinations that exhibit the desired color. In addition, even when the final color of the emitted light is white, the light emission color of both light emitting elements should be appropriately selected from the combination of colors complementary to each other, other than the combination of magenta and green. Is possible. Furthermore, even if elements that emit white light having different colors are used for the first light emitting element and the second light emitting element, the uniform white covering without color unevenness can be obtained without adjusting the variation in the color. An irradiated surface can be obtained.

  As described above, in the illumination device according to the embodiment of the present invention, the incident part and the emission part may be independent for each light emitting element or may be common to both light emitting elements. Alternatively, one of the incident portion and the emission portion may be configured independently for each light emitting element, and the other may be configured common to both light emitting elements. In addition, the shape of the emission part can be appropriately determined from the shape of emitting the light that has reached the emission part without being totally reflected, and may be the concave curved surface or the convex slope described above. The shape may be a concave or convex portion or a flat surface.

  In the above-described embodiment, each surface light source device further includes a light scattering member in addition to the light flux controlling member. However, if sufficient color mixing of the emission colors is possible only by the light flux controlling member, The lighting device may not have a light scattering member. For example, a light flux control member having a light emitting portion with a convex portion, such as the light flux control member of the second embodiment, may be able to mix colors with good emission colors without having a light scattering member.

  Further, in the above-described embodiment, the surface light source device is specifically described as the lighting device, but the form of the lighting device can be appropriately selected according to the application. For example, in the case of a fluorescent tube type lighting device, the shape of the cover may be a cylindrical shape, or may be a shape in which a part of the cylinder is cut out.

  According to the present invention, it is possible to uniformly emit light of all colors resulting from color mixture of light emitted from two color light emitting elements without requiring individual adjustment of the light emitting elements. Therefore, according to this invention, the further expansion of the use and utilization of an illuminating device is anticipated.

DESCRIPTION OF SYMBOLS 100 Surface light source device 110 Board | substrate 120a 1st light emitting element 120b 2nd light emitting element 130,230,330,430 Light flux control member 131 Incident part 132,232,332 V-shaped groove 133 Planar part 135a, 235a 1st total reflection part 135b, 235b Second total reflection part 136, 236 Light guide part 138 Emission part 140 Light scattering member 141 Main body 142 Diffusing and transmitting part 143 Locking claw 144, 239 Protrusion 145 Concave 150 Cover 231a, 331a First incident part 231b, 331b Second Incident part 238a, 438a First emitting part 238b, 438b Second emitting part 333a First incident surface part 333b Second incident surface part 433a First planar part 433b Second planar part OA1 Optical axis of the first light emitting element OA2 of the second light emitting element optical axis

Claims (9)

A first light-emitting element and a second light-emitting element that are arranged side by side in the first direction, have different emission colors, and each have an optical axis along a second direction orthogonal to the first direction; ,
A light flux controlling member that covers the first and second light emitting elements from the second direction;
A diffusing member disposed at a position away from the light flux controlling member in the second direction;
A lighting device comprising:
The light flux controlling member is
An incident portion that covers the first light emitting element and the second light emitting element away from them from the second direction, and receives light emitted from the first light emitting element and the second light emitting element;
A total reflection part for totally reflecting a part of the light incident from the incident part in a third direction orthogonal to the first direction and the second direction;
The other part of the light incident from the incident part, disposed at a position adjacent to the optical axis side end of the first light emitting element and the second light emitting element of the total reflection part in the third direction. An emission part for emitting the light outward,
The total reflection portion extends from the end opposite to the optical axis in the third direction in the third direction, and guides the incident light in the third direction and exits outward. Hikari and
Have
In the cross section including the optical axis of the first light emitting element and the optical axis of the second light emitting element,
The intersection of one light emitting element of the first light emitting element and the second light emitting element and the optical axis thereof is A1,
An end on the one element side in the first direction of the other light emitting element of the first light emitting element and the second light emitting element is denoted by A2,
Of the part where the emitted light of the one light emitting element in the emitting part passes, the end on the other light emitting element side in the first direction is B1,
Of the portion where the emitted light of the other light emitting element in the emitting portion passes, the end opposite to the one light emitting element in the first direction is B2,
The intersection point of the diffusing member in a straight line passing through A1 and B1 is C1, and
When the intersection point of the diffusing member with a straight line passing through A2 and B2 is C2,
C1 is located on the outer side in the first direction than C2.
Lighting device.   The illuminating device according to claim 1, wherein the number of the output portions is one per light flux controlling member, and the B1 and the B2 coincide with each other.   2. The light emitting unit according to claim 1, wherein the light emitting part includes a first light emitting part for emitting light emitted from the first light emitting element and a second light emitting part for emitting light emitted from the second light emitting element. Lighting equipment. In the cross section,
The intersection of the optical axis of the one light emitting element and the diffusing member is C3,
The intersection of the other light emitting element and its optical axis is A3,
Of the part where the emitted light of the one light emitting element in the emitting part passes, the end on the one light emitting element side in the first direction is B3,
An intersection of the straight line passing through the A1 and the B3 and the diffusion member is C4,
The ratio I1 / I2 of the light intensity I1 from the one light emitting element going from the A1 to the C3 to the light intensity I2 from the other light emitting element going from the A3 to the C3 is IA, and
When the ratio I3 / I4 of the light intensity I3 from the one light emitting element heading from the A1 to the C4 to the light intensity I4 from the other light emitting element heading from the A3 to the C4 is IB ,
The IA is 0.9 to 1.1 times the IB;
The illuminating device as described in any one of Claims 1-3.   The illumination device according to any one of claims 1 to 4, wherein the number of the incident portions is one per one light flux controlling member.   The said incident part contains the 1st incident part which receives the emitted light of the said 1st light emitting element, and the 2nd incident part which receives the emitted light of the said 2nd light emitting element. The lighting device described.   The illumination device according to any one of claims 1 to 6, wherein the emission unit is configured by a concave curved surface that is recessed with respect to an emission direction of the light.   The lighting device according to claim 1, further comprising a light scattering member that covers the emission portion from the second direction. The light flux controlling member used in the illumination device according to claim 2,
The exit part and the incident part are both one,
In the first direction, the positions of both ends of the emitting portion are positions separated from the optical axis positions of the first light emitting element and the second light emitting element.
Luminous flux control member.

Images