JP6183582B2 - Lighting device and projector - Google Patents

Description

  The present invention relates to a lighting device and a projector.

  In recent years, with the development of solid-state light sources, development of projectors using light emitting diodes (LEDs), laser diodes (Laser Diodes: LDs), super luminescent diodes (Super Luminescent Diodes: SLDs), etc. has been promoted. ing. These light sources have a small light output per light emitting point compared to currently used mercury lamps, and it is necessary to have a large number of light emitting points in order to ensure the brightness required for the projector. is there.

  As an illuminating device having a large number of light emitting points, a configuration as in Patent Document 1 is known. Patent Document 1 includes a light emitting element array and a light distribution distribution correction optical system (for example, a collimator lens) that makes an inclination of an illuminance distribution curve by light from the light emitting element on the illumination target surface substantially linear. A lighting device is disclosed.

JP 2010-186754 A

  However, in the illumination device as described above, for example, when the light emitting element is displaced with respect to the collimating lens, the optical axis of the light emitted from the light emitting element is accordingly displaced, and uneven illumination may occur on the illumination surface. As a result, an illumination surface having a uniform illuminance distribution may not be obtained.

  One of the objects according to some aspects of the present invention is to provide an illumination device that can illuminate an illumination surface with good uniformity. Another object of some aspects of the present invention is to provide a projector including the lighting device.

The lighting device according to the present invention includes:
A light source having a plurality of light emitting portions;
An optical system on which light emitted from the plurality of light emitting units is incident;
Including
The optical system is
A first lens that receives light emitted from the light emitting unit and reduces a radiation angle of the light emitted from the light emitting unit;
A second lens on which light emitted from the first lens enters;
A diffusing plate that receives light emitted from the second lens and increases a radiation angle of the light emitted from the second lens;
Have
The second lens is provided so that the light emitting portion and the illumination surface irradiated with the light emitted from the diffusion plate are in a conjugate relationship with respect to the principal ray.

According to such an illumination device, according to such an illumination device, the illumination surface can be illuminated with good uniformity.

In the lighting device according to the present invention,
A light guide that guides light emitted from the diffusion plate to the illumination surface may be included.

  According to such an illuminating device, the light emitted from the diffusion plate can be more reliably irradiated onto the illumination surface, and the loss of light can be reduced.

In the lighting device according to the present invention,
The focal length of the second lens may be greater than the focal length of the first lens.

  According to such an illuminating device, the illumination surface can be illuminated with good uniformity.

In the lighting device according to the present invention,
The distance between the light emitting unit and the second lens may be 1 to 5 times the distance between the second lens and the illumination surface.

  According to such an illuminating device, it is possible to provide an optical system in which positional deviation is suppressed on the illumination surface.

In the lighting device according to the present invention,
The light emitted from the light emitting unit may be a convergent light beam by the first lens.

  According to such an illuminating device, the proportion of light that cannot enter the second lens can be reduced, and loss of light can be reduced.

In the lighting device according to the present invention,
The number of the first lenses and the number of the second lenses may be the same.

  According to such an illuminating device, it can design easily.

The projector according to the present invention is
A spatial light modulation device that modulates light emitted from the illumination device according to image information;
A projection device for projecting an image formed by the spatial light modulation device;
Including
The lighting device includes:
A light source having a plurality of light emitting portions;
An optical system on which light emitted from the light emitting unit is incident;
Including
The optical system is
A first lens that receives light emitted from the light emitting unit and reduces a radiation angle of the light emitted from the light emitting unit;
A second lens on which light emitted from the first lens enters;
A diffusing plate that receives light emitted from the second lens and increases a radiation angle of the light emitted from the second lens;
Have
The second lens is provided so that the light emitting portion and the illumination surface irradiated with the light emitted from the diffusion plate are in a conjugate relationship with respect to the principal ray.

According to such a projector, since the illumination device that can illuminate the illumination surface with good uniformity is included, uneven luminance can be reduced.
The lighting device according to the present invention includes:
A light source having a plurality of light emitting units; and an optical system on which light emitted from the plurality of light emitting units is incident. The optical system is configured to receive light emitted from the light emitting unit and from the light emitting unit. A first lens that reduces the radiation angle of the emitted light; a second lens that receives light emitted from the first lens; and a light that emerges from the second lens enters the second lens. A diffuser that increases the radiation angle of the emitted light, and the second lens has the light emitting part and an illumination surface that is irradiated with the light emitted from the diffuser as a principal ray. A light guide is provided so as to have a conjugate relationship and guides the light emitted from the diffusion plate to the illumination surface.
In the lighting device according to the present invention,
The focal length of the second lens may be greater than the focal length of the first lens.
In the lighting device according to the present invention,
The distance between the illumination surface and the second lens may be 1 to 5 times the distance between the second lens and the light emitting unit.
In the lighting device according to the present invention,
The light emitted from the light emitting unit may be a convergent light beam by the first lens.
In the lighting device according to the present invention,
The number of the first lenses and the number of the second lenses may be the same.
The projector according to the present invention is
An illumination device; a spatial light modulation device that modulates light emitted from the illumination device according to image information; and a projection device that projects an image formed by the spatial light modulation device. Includes a light source having a plurality of light emitting units, and an optical system on which light emitted from the light emitting unit is incident, and the optical system receives light emitted from the light emitting unit and is emitted from the light emitting unit. A first lens that reduces the radiation angle of the emitted light; a second lens that receives light emitted from the first lens; and a light that emerges from the second lens enters the second lens. Shoot
A diffusing plate that increases the radiation angle of the emitted light, and the second lens has a chief ray including the light emitting unit and an illumination surface irradiated with light emitted from the diffusing plate. A light guide is provided so as to have a conjugate relationship and guides the light emitted from the diffusion plate to the illumination surface.

The figure which shows typically the illuminating device which concerns on this embodiment. The figure which shows typically the light source of the illuminating device which concerns on this embodiment. The figure for demonstrating the conjugate relationship in the principal ray of a light emission part and an illumination surface. The figure which shows an illumination surface typically. The figure for demonstrating the position shift of the light emitting element with respect to a 1st lens. The figure which shows typically the case where the light inject | emitted from a 1st lens is parallel light, and the case where the light inject | emitted from a 1st lens is the condensed light. The figure which shows typically the illuminating device which concerns on the modification of this embodiment. 1 is a diagram schematically showing a projector according to an embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unduly limit the contents of the present invention described in the claims. In addition, not all of the configurations described below are essential constituent requirements of the present invention.

1. Lighting Device First, the lighting device according to the present embodiment will be described with reference to the drawings. FIG. 1 is a diagram schematically illustrating an illumination device 100 according to the present embodiment. FIG. 2 is a diagram schematically showing the light source 10 of the illumination device 100 according to the present embodiment, as viewed from the Z-axis direction. For convenience, the support substrate 16 is not shown in FIG. In FIGS. 1 and 2 and FIGS. 3 to 7 shown below, an X axis, a Y axis, and a Z axis are illustrated as three axes orthogonal to each other.

  The illumination device 100 includes a light source 10 and an optical system 102 as shown in FIGS. Further, the lighting device 100 can include a light guide 50.

  The light source 10 includes a light emitting element 12 and a support substrate 16. A plurality of light emitting elements 12 are provided. Although the number of the light emitting elements 12 is not particularly limited, in the example shown in FIG. 2, three light emitting elements 12 are provided and arranged in the Y-axis direction.

  The light emitting element 12 has a plurality of light emitting portions 14. Although the number of the light emission parts 14 is not specifically limited, In the example shown in FIG. 2, five light emission parts 14 are provided in one light emitting element 12, and are arranged in the X-axis direction. The light emitting units 14 are arranged in a matrix in the X-axis direction and the Y-axis direction. The light emitting units 14 are arranged at equal intervals in the X-axis direction and the Y-axis direction.

  Although not shown, the light-emitting element 12 may have one light-emitting portion 14, and the light-emitting elements 12 having one light-emitting portion 14 are arranged in a matrix in the X-axis direction and the Y-axis direction. May be.

  The light emitting element 12 can emit light (light flux) from the light emitting unit 14. In the illustrated example, the emission direction of the light emitted from the light emitting unit 14 is the Z-axis direction. The light emitting element 12 is, for example, an SLD, LD, or LED. The SLD can prevent laser oscillation and can reduce speckle noise compared to the LD.

  The support substrate 16 supports the light emitting element 12. Although the shape of the support substrate 16 will not be specifically limited if the light emitting element 12 can be supported, For example, it is plate shape. The material of the support substrate 16 is, for example, copper or aluminum. By using the support substrate 16 of such a material, the heat dissipation of the light source 10 can be improved.

  The light emitted from the plurality of light emitting units 14 enters the optical system 102. The optical system 102 includes a first lens array 20 (first lens 22), a second lens array 30 (second lens 32), and a diffusion plate 40. Although not shown, the optical system 102 may include optical members other than the lenses 22 and 32 and the diffusion plate 40.

  The first lens array 20 includes a plurality of first lenses 22. A plurality of first lenses 22 are provided corresponding to the number of light emitting units 14. The light emitted from the light emitting unit 14 is incident on the first lens 22. The principal ray of the light emitted from the light emitting unit 14 passes through, for example, the center of the first lens 22 (for example, the center of the spherical surface constituting the first lens 22). Here, the “principal ray” is a ray that passes through the center (the center of the angular distribution of the luminous flux) among the rays constituting the luminous flux. The shape of the light beam emitted from the light emitting unit 14 when viewed from the direction of the principal ray is, for example, an ellipse or a circle. In the present embodiment, the direction of the principal ray is parallel to the Z-axis direction.

  The first lens 22 can reduce the radiation angle of the light emitted from the light emitting unit 14. Specifically, the first lens 22 can emit divergent light emitted from the light emitting unit 14 as parallel light. That is, the first lens 22 can function as a collimating lens.

  In addition, the light emitted from the light emitting unit 14 may be collected by the first lens 22 (may be converged light). That is, the light emitted from the first lens 22 may travel toward one point (see FIG. 6 described later).

  The shape of the first lens 22 is not particularly limited as long as the emission angle of the light emitted from the light emitting unit 14 can be reduced. In the illustrated example, the surface of the first lens 22 on the light source 10 side is a plane. The surface on the illumination object 2 side has a convex surface (spherical surface). Although not shown, the first lens 22 may have a shape in which the surface on the light source 10 side and the surface on the illumination target 2 side are convex surfaces. The material of the first lens 22 is, for example, glass.

  The second lens array 30 includes a plurality of second lenses 32. A plurality of second lenses 32 are provided corresponding to the number of first lenses 22. The light emitted from the first lens 22 is incident on the second lens 32. The principal ray of the light emitted from the first lens 22 passes, for example, the center of the second lens 32 (for example, the center of the spherical surface constituting the second lens 32). For example, the number of the first lenses 22 and the number of the second lenses 32 are the same.

  The second lens 32 is provided so that the light emitting unit 14 and the illumination surface 4 to which the light emitted from the diffusion plate 40 is irradiated constitute an optical system 102 in a conjugate relationship with respect to the principal ray. Specifically, by providing the second lens 32 between the first lens 22 and the diffusing plate 40, the light emitting unit 14 and the illumination surface 4 can be in a conjugate relationship with respect to the principal ray. The light emitted from the diffusion plate 40 includes a diffusion component, and thus does not satisfy the above-described conjugate relationship. However, among the light that is incident on the diffusion plate 40 and emitted, the component that does not diffuse (after diffusion) The shape of the second lens 32 is set so as to satisfy the above-described conjugate relationship with respect to the central ray constituting the light beam. Therefore, as shown in FIG. 3, for example, when the light emitting element 12 is mounted, the light emitting element 12 is displaced from the position where the principal ray L travels in parallel with the Z axis, and rotates around the light emitting unit 14. Even if the traveling direction of L is inclined with respect to the Z-axis like the light beams L1 to L6, the principal light beams L1 to L6 passing through the optical system 102 can reach the same position on the illumination surface 4, for example. In this way, the positional deviation that occurs on the illumination surface 4 due to the rotation of the principal ray can be eliminated. The principal ray misalignment, which is another problem, will be described later.

FIG. 3 is a diagram for explaining a conjugate relationship in the principal ray between the light emitting unit 14 and the illumination surface 4, and a plurality of principal rays that pass through the first lens 22, the second lens 32, and the diffuser plate 40. Is illustrated. For simplicity, only the second lens 32 is shown.

As shown in FIG. 3, the distance between the light emitting part 14 and the principal point H of the second lens 32 is a, the distance between the principal point H of the second lens 32 and the illumination surface 4 is b, If the focal length of the two lenses 32 is f,
1 / a + 1 / b = 1 / f
Satisfy the relationship. Here, the “focal length” refers to a distance between a point that converges light and a principal point when light enters from infinity on the light emitting element 12 side (−Z axis direction side). The “principal point” is a principal point when light is entered from the light emitting element 12 side (−Z axis direction side).

As shown by a broken line in FIG. 3, when the light emitting element 12 emits the principal ray L7 with a shift of ΔS1 from the predetermined position (for example, from the central axis of the second lens 32) in the Y axis direction, A deviation in the Y-axis direction on the illumination surface 4 (for example, a deviation from the central axis of the second lens 32) ΔS2 is:
ΔS2 = ΔS1 × (b / a)
It becomes. Usually, ΔS1 is about 5 μm to 20 μm depending on the accuracy of the mounting apparatus. On the other hand, when the light bulb is illuminated as the illumination target 2, for example, the size of the light bulb is about 0.5 inch to 1 inch, and the positional deviation ΔS2 allowed on the illumination surface 4 is about 100 μm. For this reason, b / a should just be restrained to 5 times or less. Further, it is preferable that a is small (close to the light emitting unit 14) so that the light emitted from the light emitting unit 14 does not enter the second lens 32 adjacent to the second lens 32 which should be incident. Furthermore, since it is desirable that the light emitted from the diffuser plate 40 irradiates the illumination surface 4 in a state where the spatial intensity distribution is widened, b is preferably large (away from the illumination surface 4). In order to satisfy such a condition, it is desirable that b / a is 1 or more. Therefore, the optically desirable magnification is 1 ≦ b / a ≦ 5. By using the second lens 32 having such a magnification relationship, it is possible to provide an optical system in which the displacement on the illumination surface 4 is suppressed.

  Further, the focal length of the second lens 32 can be made larger than the focal length of the first lens 22. Thereby, since the distance between the second lens 32 and the illumination surface 4 can be increased, the light emitted from the diffusion plate 40 can illuminate the irradiation surface 4 with a wide spatial intensity distribution. Specifically, the focal length of the second lens 32 is about 8 mm, for example, and the focal length of the first lens 22 is about 1 mm, for example.

  The shape of the second lens 32 is not particularly limited as long as the light emitting unit 14 and the illumination surface 4 can be conjugated in the principal ray. In the example illustrated in FIG. 1, the second lens 32 is on the light source 10 side. The surface is a convex surface (spherical surface), and the surface on the illumination object 2 side is a flat surface. Although not shown, the second lens 32 may have a shape in which the surface on the light source 10 side and the surface on the illumination object 2 side are convex surfaces. The material of the second lens 32 is, for example, glass.

  As shown in FIG. 1, the light emitted from the second lens 32 enters the diffusion plate 40. The diffusion plate 40 can increase the radiation angle of the light emitted from the second lens 32. The light emitted from the diffusion plate 40 can travel in the Z-axis direction while spreading isotropically. The light emitted from the diffusion plate 40 can partially overlap on the illumination surface 4 (non-overlapping system). The material of the diffusion plate 40 is, for example, glass.

  Light emitted from the diffusion plate 40 enters the light guide 50. The light guide 50 can guide the light emitted from the diffusion plate 40 to the illumination surface 4. The shape of the ride guide 50 is not particularly limited, and may be a rectangular parallelepiped, or a shape in which an opening is provided in the rectangular parallelepiped so that a portion through which light passes is hollow and a reflective surface is formed on the inside. There may be. The material of the light guide 50 is, for example, glass.

  The illumination surface 4 of the illumination target 2 is irradiated with light emitted from the light guide 50. For example, when the illumination device 100 is used for a projector, the illumination target 2 is a light valve. Here, FIG. 4 is a diagram schematically showing the illumination surface 4 and is a diagram seen from the Z-axis direction. As shown in FIG. 4, it is desirable that a plurality of light source images (positions of principal rays L) are arranged at equal intervals in the X-axis direction and the Y-axis direction. Thereby, the uniformity of illuminance can be improved.

  In the above description, the example in which the plurality of first lenses 22 form the first lens array 20 has been described. However, the plurality of first lenses 22 do not form a lens array and are separated from each other. It may be a lens. Similarly, in the above description, the example in which the plurality of second lenses 32 constitute the second lens array 30 has been described. However, the plurality of second lenses 32 do not constitute a lens array but are separated from each other. This lens may be used.

  The illumination device 100 has the following features, for example.

  According to the illumination device 100, the second lens 32 is provided so that the light emitting unit 14 and the illumination surface 4 are in a conjugate relationship with respect to the principal ray. Therefore, as described above, for example, when the light emitting element 12 is mounted, the light emitting element 12 deviates from the position where the principal ray L travels in parallel with the Z axis, and rotates around the light emitting unit 14 to rotate the principal ray L. Even if the traveling direction is tilted with respect to the Z axis, the principal ray L passing through the optical system 102 can reach, for example, the same position (or substantially the same position) on the illumination surface 4 (FIG. 3). reference). Therefore, the illumination device 100 can illuminate the illumination surface 4 with good uniformity.

  For example, in the light emitting element 12 in which the emission angle of the emitted light is as large as about 35 °, the focal length of the first lens 22 is as small as about 1 mm. Therefore, as shown in FIG. 5, even if the light emitting element 12 is displaced by several tens of μm in the Y-axis direction with respect to the first lens 22 (relative to the central axis of the first lens 22), a large optical axis such as several degrees. A shift is caused, and the traveling direction of the chief ray L is shifted. In the illuminating device 100, the optical axis shift caused by the shift of the light emitting element 12 with respect to the first lens 22 can be corrected by the second lens 32.

  FIG. 5 is a diagram for explaining the positional shift of the light emitting element 12 with respect to the first lens 22, and the light emitting element 12 and the principal ray L when the position is shifted are indicated by broken lines.

  The illumination device 100 includes the light guide 50 that guides the light emitted from the diffusion plate 40 to the illumination surface 4. Thereby, the light emitted from the diffusing plate 40 can be irradiated to the illumination surface 4 more reliably, and the loss of light can be reduced.

  According to the lighting device 100, the focal length of the second lens 32 is larger than the focal length of the first lens 22. Therefore, since the distance between the second lens 32 and the illumination surface 4 can be increased, the light emitted from the diffusion plate 40 can illuminate the irradiation surface 4 with a wide spatial intensity distribution (FIG. 3). reference). Therefore, in the illumination device 100, the illumination surface 4 can be illuminated with good uniformity.

  According to the illumination device 100, the distance between the light emitting unit 14 and the second lens 32 can be set to be 1 to 5 times the distance between the second lens and the illumination surface 4. Thereby, as described above, it is possible to provide an optical system in which the displacement on the illumination surface 4 is suppressed.

  According to the illuminating device 100, the first lens 22 can collect the light emitted from the light emitting unit 14 (to make it a convergent light beam). Thereby, the loss of light can be reduced. This will be specifically described below.

  For example, when the light emitting element 12 is displaced in the Y-axis direction with respect to the first lens 22 (relative to the central axis of the first lens 22), the light is emitted from the first lens 22 as shown in FIG. When the light (light beam B) is parallel light, a part of the light beam B emitted from the first lens 22 cannot enter the second lens 32 and may be lost. Specifically, the width (the size in the Y-axis direction) of the light beam B emitted from the first lens 22 is 0.5 mm, and the effective diameter (for example, the size in the Y-axis direction) of the second lens 32 is 0. If it is 7 mm, light loss occurs when the central axis (the position of the principal ray) of the light beam B deviates by 0.2 mm or more from the center of the incident surface (center viewed from the Z-axis direction) on the incident surface of the second lens 32 End up. On the other hand, as shown in FIG. 6B, when the light beam B emitted from the first lens 22 is condensed light, the second lens 32 is compared with the case shown in FIG. The light beam diameter at the incident surface can be reduced. Therefore, the ratio of the light beam B that cannot enter the second lens 32 can be reduced, and the loss of light can be reduced.

  FIG. 6 schematically illustrates a case where the light emitted from the first lens 22 is parallel light and a case where the light emitted from the first lens 22 is condensed light (converged light). The light emitting element 12 and the light beam B when the positions are shifted are indicated by broken lines. In any case, the shape of the second lens 32 is set so that the light emitting unit 14 and the illumination surface 4 satisfy the conjugate relationship in the principal ray. The conjugate relationship in the state where the diffusion plate 40 is provided between the second lens 32 and the light guide 50 is as described above.

  According to the illumination device 100, the number of the first lenses 22 and the number of the second lenses 32 can be made the same. Thereby, the illuminating device 100 can be designed easily.

2. Next, a lighting device according to a modification of the present embodiment will be described with reference to the drawings. FIG. 7 is a diagram schematically showing an illumination device 200 according to a modification of the present embodiment. Hereinafter, in the illuminating device 200 according to the modified example of the present embodiment, members having the same functions as the constituent members of the illuminating device 100 according to the present embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. For convenience, the support substrate 16 is not shown in FIG.

  In the illumination device 100, as shown in FIG. 1, the second lenses 32 constituting the second lens array 30 are arranged at an equal pitch in the Y-axis direction. On the other hand, in the illumination device 200, as shown in FIG. 7, the second lenses 32 do not constitute a lens array, and are arranged at different pitches along the Y-axis direction. In the illustrated example, the plurality of second lenses 32 are arranged such that the interval between the adjacent second lenses 32 increases from the inside toward the outside in the Y-axis direction. Thereby, the pitch D1 of the light emitting element 12 and the pitch D2 of the principal ray position on the illumination surface 4 can be set to different values.

3. Next, the projector according to the present embodiment will be described with reference to the drawings. FIG. 8 is a diagram schematically showing a projector 800 according to the present embodiment. For the sake of convenience, FIG. 8 does not show the casing constituting the projector 800.

  The projector 800 includes the lighting device according to the present invention. Hereinafter, as shown in FIG. 8, a projector 800 including the illumination device 100 (the illumination device 100R, the illumination device 100G, and the illumination device 100B) will be described. The illumination device 100R, the illumination device 100G, and the illumination device 100B can emit red light, green light, and blue light, respectively. For convenience, in FIG. 8, the lighting device 100R, the lighting device 100G, and the lighting device 100B are illustrated in a simplified manner.

  As shown in FIG. 8, the projector 800 further includes transmissive liquid crystal light valves (spatial light modulation devices) 804R, 804G, and 804B, and a projection lens (projection device) 808. The liquid crystal light valves 804R, 804G, and 804B correspond to the illumination target 2 shown in FIG.

  Light emitted from each of the lighting devices 100R, 100G, and 100B enters each liquid crystal light valve 804R, 804G, and 804B. Each of the liquid crystal light valves 804R, 804G, and 804B modulates incident light according to image information. The projection lens 808 enlarges and projects an image formed by the liquid crystal light valves 804R, 804G, and 804B onto a screen (display surface) 810.

  In addition, the projector 800 can include a cross dichroic prism (color light combining unit) 806 that combines the light emitted from the liquid crystal light valves 804R, 804G, and 804B and guides the light to the projection lens 808.

  The three color lights modulated by the liquid crystal light valves 804R, 804G, and 804B are incident on the cross dichroic prism 806. This prism is formed by bonding four right-angle prisms, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are arranged in a cross shape on the inner surface thereof. These dielectric multilayer films combine the three color lights to form light representing a color image. The synthesized light is projected onto the screen 810 by the projection lens 808 which is a projection optical system, and an enlarged image is displayed.

  The projector 800 includes the illumination device 100 that can illuminate the illumination target with good uniformity. Therefore, the projector 800 can reduce luminance unevenness.

  In the above example, a transmissive liquid crystal light valve is used as the spatial light modulator, but a light valve other than liquid crystal may be used, or a reflective light valve may be used. Examples of such a light valve include a reflection type liquid crystal light valve and a digital micromirror device (Digital Micromirror Device). Further, the configuration of the projection optical system is appropriately changed depending on the type of light valve used.

  Further, 100R, 100G, and 100B are also applied to an illumination device of a scanning type image display device (projector) that displays an image of a desired size on a display surface by scanning light from a light source on a screen. It is possible.

  The above-described embodiments and modifications are merely examples, and the present invention is not limited to these. For example, it is possible to appropriately combine each embodiment and each modification.

  The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same objects and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

DESCRIPTION OF SYMBOLS 2 ... Illumination object, 4 ... Illumination surface, 10 ... Light source, 12 ... Light emitting element, 14 ... Light emission part, 16 ... Support substrate, 20 ... 1st lens array, 22 ... 1st lens, 30 ... 2nd lens array, 32 DESCRIPTION OF SYMBOLS 2nd lens, 40 ... Diffusing plate, 50 ... Light guide, 100 ... Illuminating device, 102 ... Optical system, 200 ... Illuminating device, 800 ... Projector, 804 ... Liquid crystal light valve, 806 ... Cross dichroic prism, 808 ... Projection lens 810 ... Screen

Claims (6)

A light source having a plurality of light emitting portions;
An optical system on which light emitted from the plurality of light emitting units is incident;
Including
The optical system is
A first lens that receives light emitted from the light emitting unit and reduces a radiation angle of the light emitted from the light emitting unit;
A second lens on which light emitted from the first lens enters;
A diffusing plate that receives light emitted from the second lens and increases a radiation angle of the light emitted from the second lens;
Have
The second lens is provided so that the light emitting portion and the illumination surface irradiated with the light emitted from the diffusion plate are in a conjugate relationship with respect to a principal ray .
An illumination device comprising: a light guide for guiding light emitted from the diffusion plate to the illumination surface . The focal length of the second lens is larger than the focal length of the first lens, the illumination device according to claim 1, characterized in that. 3. The lighting device according to claim 1, wherein a distance between the illumination surface and the second lens is 1 to 5 times a distance between the second lens and the light emitting unit . The light emitted from the light emitting unit, said a convergent light beam by the first lens, the illumination apparatus according to 3 any one claims 1, characterized in that. Wherein a is the number the number of the second lens of the first lens is the same, the lighting device according to any one of claims 1 to 4, characterized in that. A lighting device;
A spatial light modulation device that modulates light emitted from the illumination device according to image information;
A projection device for projecting an image formed by the spatial light modulation device;
Including
The lighting device includes:
A light source having a plurality of light emitting portions;
An optical system on which light emitted from the light emitting unit is incident;
Including
The optical system is
A first lens that receives light emitted from the light emitting unit and reduces a radiation angle of the light emitted from the light emitting unit;
A second lens on which light emitted from the first lens enters;
A diffusing plate that receives light emitted from the second lens and increases a radiation angle of the light emitted from the second lens;
Have
The second lens is provided so that the light emitting portion and the illumination surface irradiated with the light emitted from the diffusion plate are in a conjugate relationship with respect to a principal ray .
A projector comprising a light guide for guiding light emitted from the diffusion plate to the illumination surface .

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