JP2016072092A - Lighting device and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lighting device capable of improving uniformity in distribution of light intensity even when a plurality of light emitting elements are used as a light source, and a display device including the lighting device.SOLUTION: In a lighting device 2, a reflecting member 8 is disposed on a plurality of light emitting elements 3 arranged in a first direction X. The reflecting member 8 includes obliquely-inclined first reflection face 41 and second reflection face 42 at both sides in the first direction X. The reflecting member 8 has a projecting portion 85 having the trapezoidal cross-sectional shape between two light emitting elements 3 adjacent to each other in the first direction X, and side faces at both sides in the first direction, of the projecting portion 85 are composed of obliquely-inclined third reflection face 43 and forth reflection face 44. The third reflection face 43 and the fourth reflection face 44 are disposed within a range not intersecting with a virtual line connecting light emitting portions 30 of the light emitting elements 3 and an end portion at one side X1 in the first direction X of a display region 90 of a light modulation device 9, and a virtual line connecting the light emitting portions 30 of the light emitting elements 3 and an end portion at the other side X2 in the first direction X of the display region 90 of the light modulation device 9.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an illumination device using a plurality of light emitting elements as a light source, and a display device including the illumination device.

  As a lighting device used for a head-up display or the like, a configuration using a plurality of light emitting elements such as light emitting diodes (LEDs) as a light source has been proposed. In that case, a plurality of first lenses having a positive power are provided in a one-to-one relationship with each of the plurality of light emitting elements, and a second lens on which light emitted from each of the plurality of first lenses is incident. (See Patent Document 1).

JP 2011-90217 A

  As shown in FIGS. 5 (a) and 5 (b), the inventor of the present application differs from the technique described in Patent Document 1 in that the entire display area 90 of the light modulation device 9 such as a liquid crystal device is used without using a lens. We are studying a lighting device that can uniformly illuminate. Specifically, in the illuminating device shown in FIGS. 5A and 5B, a plurality of light emitting elements 3, for example, two light emitting elements 3, with the outgoing optical axis L 0 directed in the direction along the device optical axis L, They are arranged in a first direction X orthogonal to the device optical axis L. Further, at a position adjacent to the light emitting element 3 disposed on the one side X1 in the first direction X on the one side X1 in the first direction X, the light emitting element 3 tilts obliquely with respect to the emission optical axis L0. Is provided at a position adjacent to the light emitting element 3 disposed on the other side X2 in the first direction X on the other side X2 of the first direction X. A second reflecting surface 42 that is inclined obliquely with respect to the axis L0 and faces in the direction of light emission from the light emitting element 3 is provided. According to such a configuration, the light emitted from the light emitting element 3 can be applied to the light modulation device 9 via the optical element 5 such as a prism sheet, and the light emitted from the light emitting element 3 can be irradiated to the first reflecting surface. After being reflected by 41 and the second reflecting surface 42, the light modulation device 9 can be irradiated through the optical element 5 such as a prism sheet.

  However, in the illuminating device shown in FIGS. 5A and 5B, since the light emitting element 3 is provided apart from each other, as shown in FIG. In the light intensity distribution of the illumination light that has reached, there is a problem that the light intensity increases at the two locations 2a and 2b corresponding to the front surfaces of the two light emitting elements 3. The configuration shown in FIG. 5 is a reference example for the present invention and is not a conventional example.

  In view of the above problems, an object of the present invention is to provide an illuminating device capable of improving the uniformity of light intensity distribution even when a plurality of light emitting elements are used as a light source, and a display device including the illuminating device. It is to provide.

In order to solve the above-described problem, an illumination device according to the present invention includes a plurality of light emitting elements arranged in a first direction orthogonal to the device optical axis with the output optical axis directed in a direction along the device optical axis, Among the plurality of light emitting elements, the light emitting element is inclined obliquely with respect to the emission optical axis at a position adjacent to one side of the first direction with respect to the light emitting element disposed on the most side of the first direction. At a position adjacent to the other side of the first direction with respect to the light emitting element arranged on the other side of the first direction among the plurality of light emitting elements. A second reflecting surface inclined obliquely with respect to the emission optical axis and directed in a light emitting direction from the light emitting element, and the two light emitting elements adjacent to each other in the first direction in the plurality of light emitting elements. Oblique with respect to the outgoing optical axis at a position adjacent to one of the light emitting elements The third reflecting surface that is inclined to face the direction of light emission from the light emitting element and the second light emitting element between the two light emitting elements and adjacent to the other of the two light emitting elements are inclined with respect to the emission optical axis. And a fourth reflecting surface facing in the light emitting direction from the light emitting element.

  In the present invention, the light emitted from the light emitting element is emitted as illumination light, and the light emitted from the light emitting element toward the outside in the first direction is the first reflecting surface and the second reflection. Reflected by the surface and emitted as illumination light. For this reason, since the light radiate | emitted toward the outer side of the 1st direction is also utilized as illumination light, the utilization efficiency of light can be improved. In addition, among the light emitted from the light emitting element, the light emitted toward the inside in the first direction is reflected by the third reflecting surface and the fourth reflecting surface and emitted as illumination light. Uniformity can be improved.

  In the present invention, the light-emitting element includes a reflection member on which the first reflection surface, the second reflection surface, the third reflection surface, and the fourth reflection surface are formed, and the reflection member includes the light-emitting element. A plurality of arrangement portions formed in the first direction; a plurality of light emitting element arrangement portions; and a plurality of protrusions protruding from the bottom portion between two light emitting element arrangement portions adjacent in the first direction. A first side wall protruding from the bottom at a position adjacent to one side in the first direction with respect to the light emitting element placement part provided on the most one side in the first direction, A second side wall protruding from the bottom at a position adjacent to the other side in the first direction with respect to the light emitting element placement part provided on the other side in the first direction among the plurality of light emitting element placement parts; An inner surface of the first side wall, the second side wall The inner surface, the side surface on one side in the first direction of the convex portion, and the side surface on the other side in the first direction of the convex portion are all inclined surfaces inclined obliquely with respect to the emission optical axis. The first reflecting surface is formed on the inner surface of the first side wall, the second reflecting surface is formed on the inner surface of the second side wall, and the third reflecting surface is the first of the convex portion. Preferably, the fourth reflection surface is formed on the side surface on the other side in the first direction of the convex portion. According to such a configuration, the configuration of the lighting device can be simplified, and it is easy to dispose each reflecting surface at an appropriate position with respect to the light emitting element.

  In this invention, it is preferable that the light emission part of these light emitting elements exists in the same height position as the said bottom part, or a position higher than the said bottom part in the direction where the said emitted optical axis is extended. According to such a configuration, it is possible to suppress the light emitted from the light emitting element from being blocked by the bottom of the reflecting member.

  In the present invention, the reflecting member includes a third side wall protruding from the bottom portion on one side of the device optical axis and the second direction orthogonal to the first direction with respect to the plurality of light emitting elements, and the plurality of light emitting elements. And a fourth side wall projecting from the bottom on the other side of the second direction with respect to the element. According to this configuration, the reflecting member can be used as a cover for the light emitting element.

  In the present invention, both of the inner surface of the third side wall and the inner surface of the fourth side wall are inclined surfaces that are inclined obliquely with respect to the emission optical axis and directed in the light emitting direction from the light emitting element, The inner surface of the third side wall is preferably a fifth reflecting surface, and the inner surface of the fourth side wall is preferably a sixth reflecting surface. According to this configuration, out of the light emitted from the light emitting element, the light emitted toward the outside in the second direction can be reflected by the fifth reflecting surface and the sixth reflecting surface and emitted as illumination light. . For this reason, since the light radiate | emitted toward the outer side of the 2nd direction is also utilized as illumination light, while being able to improve the utilization efficiency of light, the uniformity of intensity distribution of light can be improved.

  In the present invention, an angle formed by the first reflecting surface, the second reflecting surface, the third reflecting surface, and the fourth reflecting surface with the outgoing optical axis is greater than 45 ° and less than 80 °. preferable. According to this structure, it can suppress that the light reflected on the 1st reflective surface, the 2nd reflective surface, the 3rd reflective surface, and the 4th reflective surface is concentrated and irradiated.

  The illumination device according to the present invention can be used for a display device. In this case, the display device includes the illumination device according to the present invention and a light modulation device that modulates illumination light emitted from the illumination device. ing.

  In this case, the third reflecting surface and the fourth reflecting surface are an imaginary line connecting the light emitting portion of the light emitting element and the one end portion in the first direction of the display area of the light modulation device, and the light emission. It is preferable that it is provided in a range that does not intersect with an imaginary line connecting the light emitting portion of the element and the other end portion in the first direction of the display region of the light modulation device. According to such a configuration, it is possible to make the light emitted from the light emitting element reach the entire display area of the light modulation device.

In the present invention, a distance in the first direction between the light emitting portion of the light emitting element and an intermediate position between the third reflecting surface and the fourth reflecting surface is a, and the third reflecting surface and the fourth reflecting surface are defined as a. The distance in the first direction between the intermediate position and the end of the display area is b, the distance between the light emitting part of the light emitting element and the display area in the direction along the emission optical axis is h, The light emitting part of the light emitting element, the end of the third reflecting surface opposite to the light emitting element in the extending direction of the outgoing optical axis, and the light emission of the fourth reflecting surface in the extending direction of the outgoing optical axis When the distance in the direction along the outgoing optical axis with the end opposite to the element is hr,
The distances a, b, h, and hr are expressed by the following formula: hr ≦ ((ac) × h) / (a + b)
It is preferable to satisfy. According to such a configuration, it is possible to satisfy a condition that the third reflecting surface and the fourth reflecting surface do not intersect with an imaginary line connecting the light emitting portion of the light emitting element and the end portion of the display area of the light modulation device.

  In the present invention, the light emitted from the light emitting element is emitted as illumination light, and the light emitted from the light emitting element toward the outside in the first direction is the first reflecting surface and the second reflection. Reflected by the surface and emitted as illumination light. For this reason, since the light radiate | emitted toward the outer side of the 1st direction is also utilized as illumination light, the utilization efficiency of light can be improved. In addition, among the light emitted from the light emitting element, the light emitted toward the inside in the first direction is reflected by the third reflecting surface and the fourth reflecting surface and emitted as illumination light. The uniformity can be further enhanced.

It is explanatory drawing of the illuminating device which concerns on Embodiment 1 of this invention. It is explanatory drawing of another optical element used for the illuminating device to which this invention is applied. It is explanatory drawing of the illuminating device which concerns on Embodiment 2 of this invention. It is a perspective view of the illuminating device which concerns on Embodiment 3 of this invention. It is explanatory drawing of the conventional illuminating device.

An illumination device and a display device to which the present invention is applied will be described with reference to the drawings. In the following description, the direction along the device optical axis L is the Z direction, the first direction orthogonal to the device optical axis L (Z direction) is the X direction, and the device optical axis L (Z direction) and the first direction are the same. A second direction orthogonal to the direction (X direction) is taken as a Y direction. In the present embodiment, a horizontally long image is displayed by the light modulation device, and the first direction X corresponds to the horizontal direction of the image, and the second direction Y corresponds to the vertical direction of the image. . Further, in the drawings, the unevenness of the first optical element and the second optical element is shown enlarged by reducing the number of unevenness so that the shape and the like can be easily understood. In the following description, the corresponding members are described with the same reference numerals so that the correspondence with the configuration described with reference to FIG. 5 can be easily understood.

[Embodiment 1]
(overall structure)
FIG. 1 is an explanatory diagram of a lighting device according to Embodiment 1 of the present invention. FIGS. 1A, 1B, and 1C are a perspective view of the lighting device, an XZ sectional view of the display device, and FIG. It is explanatory drawing which shows the simulation result of the light intensity distribution of illumination light.

  The illuminating device 2 shown to Fig.1 (a) is used for the display apparatus 1 etc. which are shown in FIG.1 (b). The display device 1 includes an illumination device 2 and a light modulation device 9 that modulates and emits illumination light emitted from the illumination device 2. The display device 1 is used as a projection display device such as a head-up display or a direct-view display device. In this embodiment, the light modulation device 9 is a transmissive liquid crystal device, and includes a liquid crystal panel and a polarizing plate and the like disposed on both sides of the liquid crystal panel. When displaying a color image, the liquid crystal panel used in the light modulation device 9 is provided with a predetermined color filter for each pixel.

  As shown in FIGS. 1A and 1B, the illumination device 2 has a plurality of light-emitting elements 3 arranged in the first direction X, and each of the plurality of light-emitting elements 3 is a device optical axis. The outgoing optical axis L0 is directed in a direction along the L (Z direction). In the present embodiment, two light emitting elements 3 are arranged in the first direction X. The plurality of light emitting elements 3 are light emitting diodes that emit white light, and are mounted on, for example, a common wiring board 39. The light emitting element 3 emits divergent light.

  In the display device 1 using the illumination device 2, the optical element 5 is disposed on the emission side from the plurality of light emitting elements 3, and the light emitted from the plurality of light emitting elements 3 is transmitted through the optical element 5. The light enters the display area 90 of the modulation device 9. In this embodiment, the optical element 5 includes, for example, a prism sheet in which a plurality of triangular prisms extending in the first direction X are arranged in the second direction Y, and a plurality of triangular prisms extending in the second direction Y are arranged in the X direction. A prism sheet and a diffusion plate.

  The irradiation area of the illumination light from the illumination device 2 (the display area 90 of the light modulation device 9) has a rectangular shape in which the first direction X (horizontal direction) is larger than the second direction Y (vertical direction). For this reason, the plurality of light emitting elements 3 are linearly arranged in one row in the first direction X.

(Structure of reflecting surface)
In the illumination device 2 of the present embodiment, a reflective surface described below is configured for the light emitting element 3. First, among the plurality of light emitting elements 3, a position adjacent to one side X1 in the first direction X with respect to the light emitting element 3 arranged on the most one side X1 in the first direction X with respect to the emission optical axis L0. A first reflecting surface 41 is provided that is inclined obliquely and faces the direction of light emission from the light emitting element 3. Similarly, among the plurality of light emitting elements 3, a position adjacent to the light emitting element 3 disposed on the other side X2 in the first direction X on the other side X2 in the first direction X is on the outgoing optical axis L0. On the other hand, a second reflecting surface 42 that is inclined obliquely and faces the direction of light emission from the light emitting element 3 is provided.

  In addition, between the two light emitting elements 3 adjacent in the first direction X in the plurality of light emitting elements 3, the light emitting elements are inclined obliquely with respect to the emission optical axis L0 at a position adjacent to one of the two light emitting elements 3. A third reflecting surface 43 facing the light emitting direction from 3 is provided. Similarly, at a position adjacent to the other of the two light emitting elements 3 between the two light emitting elements 3, a fourth reflecting surface that is inclined obliquely with respect to the emission optical axis L0 and faces in the direction of light emission from the light emitting element 3 44 is provided.

(Configuration of the reflective member 8)
In the illumination device 2, the first reflecting surface 41, the second reflecting surface 42, the third reflecting surface 43, and the fourth reflecting surface 44 are configured on the reflecting member 8. The reflecting member 8 has a bottom portion 80 in which a plurality of light emitting element arrangement portions 81 in which the light emitting elements 3 are arranged in a one-to-one relationship are formed in the first direction X. In the present embodiment, the light emitting element arrangement portion 81 includes an opening formed in the bottom portion 80. Therefore, when the wiring substrate 39 is overlapped with the bottom 80 on the side opposite to the light emitting direction from the light emitting element 3 (one side Z1 in the Z direction), the light emitting element 3 is arranged inside the light emitting element arrangement portion 81. . In this state, the light emitting sections 30 of the plurality of light emitting elements 3 are arranged in the direction in which the outgoing optical axis L0 extends in the direction of light emission from the light emitting elements 3 at the bottom 80 (the surface on the other side Z in the Z direction). ) Or a position higher than the surface of the bottom 80 in the direction of light emission from the light emitting element 3 (the surface on the other side Z in the Z direction).

  Further, the reflecting member 8 has a convex portion 85 that protrudes from the bottom 80 to the other side Z2 in the Z direction between two light emitting element arrangement portions 81 adjacent in the first direction X in the plurality of light emitting element arrangement portions 81. ing. In this embodiment, the convex portion 85 has a trapezoidal cross section.

  Further, the reflecting member 8 is located at the position adjacent to the light emitting element arrangement portion 81 provided on the most one side X1 in the first direction X on the one side X1 in the first direction X from the bottom 80 to the other side Z2 in the Z direction. And the other side in the Z direction from the bottom 80 at a position adjacent to the other side X2 of the first direction X with respect to the light emitting element arrangement part 81 arranged on the other side X2 in the first direction X. And a second side wall 87 protruding to the side Z2.

  Here, the inner surface 860 of the first side wall 86, the inner surface 870 of the second side wall 87, the first side surface 851 on one side X1 of the convex portion 85 in the first direction X, and the other side X2 of the convex portion 85 in the first direction X. Each of the second side surfaces 852 is an inclined surface inclined obliquely with respect to the outgoing optical axis L0. Accordingly, the first reflecting surface 41 is formed on the inner surface 860 of the first side wall 86, the second reflecting surface 42 is formed on the inner surface 870 of the second side wall 87, and the third reflecting surface 43 is in the first direction X of the convex portion 85. The first reflecting surface 44 is formed on the second side surface 852 on the other side X2 of the convex portion 85 in the first direction X. In this embodiment, the convex portion 85 has a trapezoidal cross section, and has an end surface 850 that faces the light emitting direction from the light emitting element 3 between the first side surface 851 and the second side surface 852.

  The reflecting member 8 further includes a third side wall 88 projecting from the bottom 80 to the other side Z2 in the Z direction on one side Y1 in the second direction Y with respect to the plurality of light emitting elements 3, and a second direction Y with respect to the plurality of light emitting elements 3. And a fourth side wall 89 projecting from the bottom 80 to the other side Z2 in the Z direction on the other side Y2. Both the inner surface 880 of the third side wall 88 and the inner surface 890 of the fourth side wall 89 are inclined surfaces that are inclined obliquely with respect to the emission optical axis L0 and directed in the direction of light emission from the light emitting element 3. The inner surface 880 of the side wall 88 is the fifth reflecting surface 45, and the inner surface of the fourth side wall 89 is the sixth reflecting surface 46.

  In this embodiment, reflecting surfaces (first reflecting surface 41, second reflecting surface 42, third reflecting surface 43, fourth reflecting surface 44, fifth reflecting surface 45, and sixth reflecting surface 46) are formed on the reflecting member 8. In this case, a reflective metal material such as aluminum or aluminum alloy is vapor-deposited on a resin molded product or the like.

  In this embodiment, the angle θ formed by the first reflecting surface 41, the second reflecting surface 42, the third reflecting surface 43, the fourth reflecting surface 44, the fifth reflecting surface 45, and the sixth reflecting surface 46 with the outgoing optical axis L0 is: The angle is greater than 45 ° and less than 80 °.

  Further, the third reflecting surface 43 and the fourth reflecting surface 44 are imaginary lines that connect the light emitting unit 30 of the light emitting element 3 and the end of one side X1 in the first direction X of the display region 90 of the light modulation device 9, and It is provided in a range that does not intersect with an imaginary line that connects the light emitting unit 30 of the light emitting element 3 and the end of the display region 90 of the light modulation device 9 on the other side X2 in the first direction X.

Such a configuration can be realized, for example, by setting the dimensions of each part as follows. Specifically, the distance in the first direction X between the light emitting unit 30 of the light emitting element 3 and the intermediate position between the third reflecting surface 43 and the fourth reflecting surface 44 is defined as a, and the third reflecting surface 43 and the fourth reflecting surface. The distance in the first direction X between the intermediate position with the surface 44 and the end of the display area 90 is b, and the distance in the direction along the emission optical axis L0 of the light emitting portion 30 of the light emitting element 3 and the display area 90 is h. And the light emitting portion 30 of the light emitting element 3 and the end of the third reflecting surface 43 opposite to the light emitting element 3 in the extending direction of the outgoing optical axis L0 and the fourth reflecting surface in the extending direction of the outgoing optical axis L0. When the distance in the direction along the outgoing optical axis L0 with the end portion on the opposite side of the light emitting element 3 of 44 is defined as hr,
The distances a, b, h, and hr are expressed by the following formula: hr / (ac) ≦ h / (a + b)
It is necessary to satisfy. Therefore, the distance hr is expressed by the following formula: hr ≦ ((ac) × h) / (a + b)
Is satisfied, the third reflecting surface 43 and the fourth reflecting surface 44 are connected to an imaginary line connecting the light emitting unit 30 of the light emitting element 3 and the end of the display region 90 of the light modulation device 9 on one side X1 in the first direction X. , And the light emitting section 30 of the light emitting element 3 and the display area 90 of the light modulation device 9 can be provided in a range that does not intersect with an imaginary line connecting the end portion on the other side X2 in the first direction X.

(Main effects of this form)
As described above, in the illumination device 2 of the present embodiment, the light emitted from the light emitting element 3 is emitted as illumination light, and the light emitted from the light emitting element 3 is directed outward in the first direction X. The emitted light is reflected by the first reflecting surface 41 and the second reflecting surface 42 and emitted as illumination light. In addition, out of the light emitted from the light emitting element 3, the light emitted toward the outside in the second direction Y is reflected by the fifth reflecting surface 45 and the sixth reflecting surface 46 and emitted as illumination light. For this reason, since the light radiate | emitted toward the outer side of the 1st direction X and the light radiate | emitted toward the outer side of the 2nd direction Y are also used as illumination light, the utilization efficiency of light can be improved.

  In addition, out of the light emitted from the light emitting element 3, the light emitted toward the inner side in the first direction X is reflected by the third reflection surface 43 and the fourth reflection surface 44 and emitted as illumination light. For this reason, even when the light intensity distribution of the illumination light reaching the display area 90 of the light modulation device 9 is provided at a spaced position as shown in FIG. 1C, the light intensity distribution is uniform. Can increase the sex. More specifically, there is a region with high light intensity over a wide region including the two locations 2a and 2b corresponding to the front surfaces of the two light emitting elements 3, and the difference in light intensity between components is small.

  The first reflecting surface 41, the second reflecting surface 42, the third reflecting surface 43, the fourth reflecting surface 44, and the fifth reflecting surface 45 and the sixth reflecting surface 46 are all formed on the reflecting member 8. . For this reason, while simplifying the structure of the illuminating device 2, each reflective surface (the 1st reflective surface 41, the 2nd reflective surface 42, the 3rd reflective surface 43, the 4th reflective surface) with respect to the light emitting element 3 can be achieved. 44, and the fifth reflecting surface 45 and the sixth reflecting surface 46) can be easily arranged at appropriate positions.

  In the reflecting member 8, the light emitting portions 30 of the plurality of light emitting elements 3 are located at the same height as the bottom 80 or higher than the bottom 80 in the direction in which the outgoing optical axis L 0 extends. For this reason, it can suppress that the light radiate | emitted from the light emitting element 3 is interrupted | blocked by the bottom part 80 of the reflection member 8. FIG.

The first reflecting surface 41, the second reflecting surface 42, the third reflecting surface 43, the fourth reflecting surface 44, the fifth reflecting surface 45, and the sixth reflecting surface 46 all have an angle formed with the outgoing optical axis L0. The angle is greater than 45 ° and less than 80 °. For this reason, the light reflected by the first reflection surface 41, the second reflection surface 42, the third reflection surface 43, the fourth reflection surface 44, and the fifth reflection surface 45 and the sixth reflection surface 46 of the light modulation device 9. It is possible to suppress the irradiation with being concentrated on a part of the display area 90. Further, the reflective member 8 is vapor-deposited to form reflective surfaces (first reflective surface 41, second reflective surface 42, third reflective surface 43, fourth reflective surface 44, fifth reflective surface 45, and sixth reflective surface 46). When forming, since the part which becomes shadow by the reflection member 8 is hard to generate | occur | produce, a vapor deposition film can be formed appropriately.

  Further, the third reflecting surface 43 and the fourth reflecting surface 44 are imaginary lines that connect the light emitting unit 30 of the light emitting element 3 and the end of one side X1 in the first direction X of the display region 90 of the light modulation device 9, and It is provided in a range that does not intersect with an imaginary line that connects the light emitting unit 30 of the light emitting element 3 and the end of the display region 90 of the light modulation device 9 on the other side X2 in the first direction X. For this reason, the light emitted from the light emitting element 3 can reach the entire display area 90 of the light modulation device 9. That is, even when the convex portion 85 including the third reflecting surface 43 and the fourth reflecting surface 44 is provided between the two light emitting elements 3, light emitted from one of the two light emitting elements 3 is converted into the light modulation device 9. The display area 90 of the light modulation device 9 can be reached over the entire display area 90, and the light emitted from the other of the two light emitting elements 3 can be reached over the entire display area 90 of the light modulation device 9. Therefore, the uniformity of the light intensity distribution can be improved in the illumination light that has reached the display area 90 of the light modulation device 9.

[Modification of Embodiment 1]
FIG. 2 is an explanatory diagram of another optical element 5 used in the illumination device 2 to which the present invention is applied. In the above embodiment, a prism sheet and a diffusion plate are used as the optical element 5. However, the first optical element 6 and the second optical element 7 described below with reference to FIG. Good. In FIG. 2, a dash-dot line is attached to the top of the second optical element 7 so that the position and the extending direction of the second convex curved surface 71 of the second optical element 7 can be easily understood.

  In the first optical element 6, a plurality of first convex curved surfaces 61 and first concave curved surfaces 62 extending continuously in the second direction Y are alternately and continuously formed in the first direction X at regular intervals. Therefore, unlike the prism sheet, the element surface constituted by the first convex curved surface 61 and the first concave curved surface 62 has a sine wave shape or a substantially sine wave shape that does not have a discontinuous portion such as a sharp top or a step. It has a cross section. Here, the first convex curved surface 61 and the first concave curved surface 62 in the first optical element 6 are formed with a period t6 with an amplitude s6.

  In contrast, in the second optical element 7, a plurality of second convex curved surfaces 71 and second concave curved surfaces 72 extending continuously in the first direction X are alternately and continuously arranged in the second direction Y at regular intervals. Is formed. Therefore, unlike the prism sheet, the element surface constituted by the second convex curved surface 71 and the second concave curved surface 72 has a sine wave shape or a substantially sine wave shape that does not have a discontinuous portion such as a sharp top or a step. It has a cross section. Here, the second convex curved surface 71 and the second concave curved surface 72 in the second optical element 7 are formed with a period t7 with an amplitude s7.

  The first optical element 6 configured as described above has power for diffusing incident light in the first direction X, but does not have such power in the second direction Y. On the other hand, the second optical element 7 has power for diffusing incident light in the second direction Y, but does not have such power in the first direction X. For this reason, since the light transmitted through the first optical element 6 and the second optical element 7 diffuses in the first direction X and the second direction Y, the uniformity of the angle component of the light beam can be improved in the illumination light. .

Here, the first optical element 6 is formed on one surface 60a of the flat or sheet-like first light transmitting member 60, and the second optical element 7 is formed of the flat or sheet-like second light transmitting member 70. It is formed on one side 70a. The first light-transmissive member 60 and the second light-transmissive member 70 are formed with the second optical element 7 and the other surface 60b opposite to the one surface 60a on which the first optical element 6 is formed. It arrange | positions so that the other surface 70b on the opposite side to the one surface 70a may oppose. In this embodiment, the other surface 60b of the first light transmissive member 60 and the other surface 70b of the second light transmissive member 70 are disposed so as to overlap each other. For this reason, the 1st optical element 6 and the 2nd optical element 7 can be arrange | positioned closely.

  In addition, the incident area of the illumination light to the 1st optical element 6 and the 2nd optical element 7 differs in the length of the 1st direction (X direction), and the 2nd direction (Y direction). Accordingly, the amplitude s6 of the first convex curved surface 61 and the first concave curved surface 62 in the first optical element 6 is different from the amplitude s7 of the second convex curved surface 71 and the second concave curved surface 72 in the second optical element 7. . Further, the period t6 of the first convex curved surface 61 and the first concave curved surface 62 in the first optical element 6 is different from the period t7 of the second convex curved surface 71 and the second concave curved surface 72 in the second optical element 7. . In this embodiment, the incident area of the illumination light to the first optical element 6 and the second optical element 7 has a rectangular shape in which the first direction X (lateral direction) is larger than the second direction Y (vertical direction). . Therefore, the amplitude a6 of the first convex curved surface 61 and the first concave curved surface 62 in the first optical element 6 is set larger than the amplitude a7 of the second convex curved surface 71 and the second concave curved surface 72 in the second optical element 7. ing. Further, the period b6 of the first convex curved surface 61 and the first concave curved surface 62 in the first optical element 6 is set longer than the period b7 of the second convex curved surface 71 and the second concave curved surface 72 in the second optical element 7. .

  In the first optical element 6 and the second optical element 7 configured as described above, the amplitude s6 of the first convex curved surface 61 and the first concave curved surface 62 in the first optical element 6, and the second convex curved surface in the second optical element 7. The amplitude s7 of both 71 and the second concave curved surface 72 is 10 μm to 50 μm. Further, the period t6 of the first convex curved surface 61 and the first concave curved surface 62 in the first optical element 6 and the period t7 of the second convex curved surface 71 and the second concave curved surface 72 in the second optical element 7 are all from 50 μm. 100 μm.

[Embodiment 2]
FIG. 3 is an explanatory diagram of the illumination device 2 according to Embodiment 2 of the present invention, and FIGS. 3A and 3B are a perspective view of the illumination device and an XZ sectional view of the display device.

  The lighting device 2 shown in FIGS. 3A and 3B also has a plurality of light emitting elements 3 arranged in the first direction X, as in the first embodiment. The outgoing optical axis L0 is directed in the direction along the device optical axis L (Z direction). In this embodiment, three light emitting elements 3 are arranged in the first direction X.

  Even in the illuminating device 2 configured as described above, the reflecting member 8 has a bottom portion 80 in which a plurality of light emitting element arrangement portions 81 in which the light emitting elements 3 are arranged are formed in the first direction X. In addition, the reflecting member 8 has a trapezoidal cross-sectional shape protruding from the bottom 80 to the other side Z2 in the Z direction between two light emitting element arrangement parts 81 adjacent in the first direction X in the plurality of light emitting element arrangement parts 81. 85. In this embodiment, since the light emitting element 3 and the light emitting element arrangement portion 81 are provided at three locations in the first direction X, the convex portions 85 are provided at two locations in the first direction X.

  Further, the reflecting member 8 is located at the position adjacent to the light emitting element arrangement portion 81 provided on the most one side X1 in the first direction X on the one side X1 in the first direction X from the bottom 80 to the other side Z2 in the Z direction. And the other side in the Z direction from the bottom 80 at a position adjacent to the other side X2 of the first direction X with respect to the light emitting element arrangement part 81 arranged on the other side X2 in the first direction X. And a second side wall 87 protruding to the side Z2. The reflecting member 8 includes a third side wall 88 projecting from the bottom 80 to the other side Z2 in the Z direction on one side Y1 in the second direction Y with respect to the plurality of light emitting elements 3, and a second direction Y with respect to the plurality of light emitting elements 3. And a fourth side wall 89 projecting from the bottom 80 to the other side Z2 in the Z direction on the other side Y2.

  Here, the inner surface 860 of the first side wall 86, the inner surface 870 of the second side wall 87, the inner surface 880 of the third side wall 88, the inner surface 870 of the fourth side wall 89, and the first side X <b> 1 in the first direction X of the convex portion 85. The side surface 851 and the second side surface 852 on the other side X2 in the first direction X of the convex portion 85 are both inclined surfaces inclined obliquely with respect to the emission optical axis L0. Accordingly, the first reflecting surface 41 is formed on the inner surface 860 of the first side wall 86, the second reflecting surface 42 is formed on the inner surface 870 of the second side wall 87, and the third reflecting surface 43 is in the first direction X of the convex portion 85. The first reflective surface 44 is formed on the second side surface 852 on the other side X2 of the convex portion 85 in the first direction X, and the fifth reflective surface 45 is formed on the third side wall 88. The sixth reflecting surface 46 is formed on the inner surface 890 of the fourth side wall 89.

  Since other configurations are the same as those of the first embodiment, description thereof is omitted.

[Embodiment 3]
FIG. 4 is a perspective view of the illumination device 2 according to Embodiment 3 of the present invention. The illumination device 2 shown in FIG. 4 also has a plurality of light emitting elements 3 arranged in the first direction X, as in the first embodiment, and the plurality of light emitting elements 3 are all along the device optical axis L. The outgoing optical axis L0 is directed in the direction (Z direction). In the present embodiment, two light emitting elements 3 are arranged in the first direction X and two light emitting elements 3 are arranged in the second direction Y, and the total number of the light emitting elements 3 is four.

  Even in the illuminating device 2 configured as described above, the reflecting member 8 has a bottom portion 80 in which a plurality of light emitting element arrangement portions 81 in which the light emitting elements 3 are arranged are formed in the first direction X. In addition, the reflecting member 8 has a trapezoidal cross-sectional shape protruding from the bottom 80 to the other side Z2 in the Z direction between two light emitting element arrangement parts 81 adjacent in the first direction X in the plurality of light emitting element arrangement parts 81. 85. In the present embodiment, the light emitting elements 3 and the light emitting element arrangement portions 81 are provided in two rows even in the second direction Y. For this reason, the convex portion 85 extends in the Y direction and extends between the two light emitting elements 3 arranged in the first direction X on one side Y1 in the second direction Y on the other side Y2 in the second direction Y. It reaches between the two light emitting elements 3 arranged in the first direction X.

  Further, the reflecting member 8 is located at the position adjacent to the light emitting element arrangement portion 81 provided on the most one side X1 in the first direction X on the one side X1 in the first direction X from the bottom 80 to the other side Z2 in the Z direction. And the other side in the Z direction from the bottom 80 at a position adjacent to the other side X2 of the first direction X with respect to the light emitting element arrangement part 81 arranged on the other side X2 in the first direction X. And a second side wall 87 protruding to the side Z2. The reflecting member 8 includes a third side wall 88 projecting from the bottom 80 to the other side Z2 in the Z direction on one side Y1 in the second direction Y with respect to the plurality of light emitting elements 3, and a second direction Y with respect to the plurality of light emitting elements 3. And a fourth side wall 89 projecting from the bottom 80 to the other side Z2 in the Z direction on the other side Y2.

  Here, the inner surface 860 of the first side wall 86, the inner surface 870 of the second side wall 87, the inner surface 880 of the third side wall 88, the inner surface 870 of the fourth side wall 89, and the first side X <b> 1 in the first direction X of the convex portion 85. The side surface 851 and the second side surface 852 on the other side X2 in the first direction X of the convex portion 85 are both inclined surfaces inclined obliquely with respect to the emission optical axis L0. Accordingly, the first reflecting surface 41 is formed on the inner surface 860 of the first side wall 86, the second reflecting surface 42 is formed on the inner surface 870 of the second side wall 87, and the third reflecting surface 43 is in the first direction X of the convex portion 85. The first reflective surface 44 is formed on the second side surface 852 on the other side X2 of the convex portion 85 in the first direction X, and the fifth reflective surface 45 is formed on the third side wall 88. The sixth reflecting surface 46 is formed on the inner surface 890 of the fourth side wall 89.

In this embodiment, the illumination light incident area (display area 90 of the light modulation device 9) has a rectangular shape in which the first direction X (horizontal direction) is larger than the second direction Y (vertical direction). For this reason, a convex portion 85 having the third reflecting surface 43 and the fourth reflecting surface 44 is formed between the two light emitting elements 3 spaced in the first direction X, but separated in the second direction Y. The convex part provided with the reflective surface is not formed between the two light emitting elements 3 to be formed. In addition, a convex part may be provided also between the two light emitting elements 3 spaced apart in the second direction Y, and a reflective surface inclined obliquely may be configured by a side surface of the convex part. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

[Other embodiments]
In the above embodiment, the illumination device 2 used for the display device 1 configured as a head-up display has been exemplified. However, the present invention can be applied to the illumination device 2 used for other display devices such as a direct-view display device. Good. In the above embodiment, a case where a transmissive liquid crystal device is used as the light modulation device 9 is exemplified. However, the present invention is applied to the illumination device 2 used in a display device using another light modulation device such as a difference in reflective liquid crystal. May be applied.

1 .... Display device 2 .... Lighting device 3 .... Light emitting element 5 .... Optical element 6 .... First optical element 7 .... Second optical element 8 .... Reflection member 9 ... Light Modulator, 30... Light emitting part, 41... First reflection surface, 42... Second reflection surface, 43... Third reflection surface, 44. ..Sixth reflecting surface 61..First convex curved surface 62..First concave curved surface 71..Second convex curved surface 72..Second concave curved surface 80..Bottom portion 81..Light emitting element arrangement , 85 .. Projection, 86 .. First side wall, 87 .. Second side wall, 88 .. Third side wall, 89 .. Fourth side wall, 90 .. Display area, 851. .. Second side surface, 860 .. Inner surface of first side wall, 870 .. Inner surface of second side wall, 880 .. Inner surface of third side wall, 890 .. Inner surface of fourth side wall, L. ..Out The optical axis, X · · first direction, Y · · second direction

Claims (9)

A plurality of light emitting elements arranged in a first direction orthogonal to the device optical axis with the outgoing optical axis directed in a direction along the device optical axis;
Among the plurality of light emitting elements, the light emitting element tilted obliquely with respect to the emission optical axis at a position adjacent to one side of the first direction with respect to the light emitting element disposed on the most side of the first direction. A first reflecting surface facing in the direction of light emission from the element;
Among the plurality of light emitting elements, the light emitting element tilted obliquely with respect to the emission optical axis at a position adjacent on the other side in the first direction with respect to the light emitting element arranged on the other side in the first direction. A second reflecting surface facing the direction of light emission from the element;
Light emission from the light emitting element is inclined with respect to the emission optical axis at a position adjacent to one of the two light emitting elements between two light emitting elements adjacent in the first direction in the plurality of light emitting elements. A third reflecting surface facing in a direction;
A fourth reflecting surface inclined obliquely with respect to the emission optical axis at a position adjacent to the other of the two light emitting elements between the two light emitting elements, and facing the light emitting direction from the light emitting element;
A lighting device comprising: A reflection member on which the first reflection surface, the second reflection surface, the third reflection surface, and the fourth reflection surface are formed;
The reflecting member includes a bottom portion in which a plurality of light emitting element arrangement portions on which the light emitting elements are arranged is formed in the first direction, and two light emitting element arrangement portions adjacent in the first direction in the plurality of light emitting element arrangement portions. Between the convex portion protruding from the bottom portion and the light emitting element arrangement portion provided on the most one side in the first direction among the plurality of light emitting element arrangement portions, adjacent on one side in the first direction. The first side wall projecting from the bottom portion at a matching position and the light emitting element arrangement portion provided on the other side in the first direction among the plurality of light emitting element arrangement portions on the other side in the first direction. A second side wall protruding from the bottom at an adjacent position,
The inner surface of the first side wall, the inner surface of the second side wall, the side surface on one side of the convex portion in the first direction, and the side surface on the other side of the convex portion in the first direction are all the outgoing optical axis. It is an inclined surface inclined obliquely with respect to,
The first reflecting surface is formed on an inner surface of the first side wall,
The second reflecting surface is formed on the inner surface of the second side wall,
The third reflection surface is formed on one side surface of the convex portion in the first direction,
The lighting device according to claim 1, wherein the fourth reflection surface is formed on a side surface on the other side in the first direction of the convex portion.   The light emitting portion of the plurality of light emitting elements is at the same height position as the bottom portion or higher than the bottom portion in the direction in which the outgoing optical axis extends. The lighting device described in 1.   The reflecting member includes a third side wall projecting from the bottom portion on one side in the second direction orthogonal to the device optical axis and the first direction with respect to the plurality of light emitting elements, and the first side with respect to the plurality of light emitting elements. 4. The lighting device according to claim 1, further comprising a fourth side wall projecting from the bottom portion on the other side in two directions. Both the inner surface of the third side wall and the inner surface of the fourth side wall are inclined surfaces that are inclined obliquely with respect to the emission optical axis and directed in the direction of light emission from the light emitting element,
The inner surface of the third side wall is a fifth reflecting surface,
The lighting device according to claim 4, wherein an inner surface of the fourth side wall is a sixth reflecting surface.   The angle formed by the first reflection surface, the second reflection surface, the third reflection surface, and the fourth reflection surface with the outgoing optical axis is greater than 45 ° and less than 80 °. Item 6. The lighting device according to any one of Items 1 to 5.   A display device comprising: the illumination device according to claim 1; and a light modulation device that modulates illumination light emitted from the illumination device.   The third reflecting surface and the fourth reflecting surface are a virtual line connecting a light emitting portion of the light emitting element and an end portion on one side in the first direction of the display area of the light modulation device, and light emission of the light emitting element. The display device according to claim 7, wherein the display device is provided in a range not intersecting with an imaginary line connecting a portion and an end portion on the other side in the first direction of the display region of the light modulation device. The distance in the first direction between the light emitting part of the light emitting element and the intermediate position between the third reflecting surface and the fourth reflecting surface is a,
The distance in the first direction between the intermediate position of the third reflecting surface and the fourth reflecting surface and the end of the display area is b,
The distance in the direction along the emission optical axis of the light emitting part of the light emitting element and the display region is h,
The light emitting portion of the light emitting element, the end of the third reflecting surface opposite to the light emitting element in the extending direction of the outgoing optical axis, and the fourth reflecting surface in the extending direction of the outgoing optical axis. When the distance in the direction along the outgoing optical axis with the end opposite to the light emitting element is hr,
The distances a, b, h, and hr are expressed by the following formula: hr ≦ ((ac) × h) / (a + b)
The display device according to claim 8, wherein: