JP5499740B2 - Lighting device and projector - Google Patents

Description

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

  Conventionally, a projector with high brightness has been demanded, and a projector having a configuration in which light from a pair of light source devices is synthesized by a triangular prism (a so-called two-lamp projector) has been proposed (for example, a projector having a high brightness) (for example, , See Patent Document 1).

  According to such a conventional two-lamp type projector, since the illumination device having a pair of light source devices is used as the illumination device, a projector with higher brightness than the conventional one can be configured.

JP 2000-3612 A

  However, in such a conventional two-lamp projector, when the light emission of any one of the pair of light source devices is weakened or cut off, the in-plane light intensity distribution in the illuminated area becomes non-uniform, As a result, there is a problem that the quality of the projected image is deteriorated. This problem is not a problem seen only in a two-lamp type projector, but is a problem commonly seen in a projector having two or more pairs of light source devices.

  Therefore, the present invention has been made to solve such a problem, and is an illumination device that can be suitably used for a high-intensity projector, in which any one of the pair of light source devices emits light. An illuminating device capable of suppressing the in-plane light intensity distribution in the illuminated area from becoming non-uniform even when weakened or cut off, and suppressing the deterioration of the quality of the projected image The purpose is to provide. Moreover, an object of this invention is to provide the projector provided with such an illuminating device.

  In order to achieve the above object, the present inventor achieves the in-plane light intensity distribution in the illuminated area when the light emission of one of the pair of light source devices is weakened or cut off in the conventional two-lamp projector. The cause of unevenness was thoroughly investigated. As a result, it has been found that the cause is that the light emitted from each of the pair of light source devices is incident on areas shifted from each other in the first lens array of the lens integrator optical system. Based on this knowledge, the present inventor has conceived that the above problem can be solved if the light emitted from each of the pair of light source devices is incident on substantially the same region in the first lens array. The present invention has been completed.

[1] That is, the illuminating device of the present invention is disposed between the first light source device and the second light source device, which are disposed substantially opposite to each other, and between the first light source device and the second light source device. The light emitted from one light source device and the light emitted from the second light source device are combined and emitted in a predetermined direction, and the in-plane light intensity distribution of the light from the light combining portion is uniform. A lens integrator optical system, wherein the light combining unit includes an optical axis of the first light source device, an optical axis of the second light source device, and an optical axis of the illumination device (hereinafter, the illumination device). The optical axis is referred to as the illumination optical axis.) When a plane parallel to all of the illumination optical axes is used as a reference plane, the optical axis is arranged on the first light source device side when viewed along a direction orthogonal to the reference plane. At an angle of approximately 45 ° with respect to the illumination optical axis. A first polarization separation / combination unit having a first polarization separation / combination surface, disposed on the second light source device side, disposed at an angle of approximately 45 ° with respect to the illumination optical axis, and the first A second polarization separation / synthesis unit having a second polarization separation / synthesis surface disposed substantially perpendicular to the polarization separation / synthesis surface, a reflection mirror disposed on a side opposite to a direction in which the light synthesis unit emits light, and the reflection A mirror, and a λ / 4 plate disposed between the first polarization separation / combination unit and the second polarization separation / combination unit, and the illumination device includes light emitted from the first light source device; The light emitted from the second light source device is incident on substantially the same region in the first lens array of the lens integrator optical system.

  For this reason, according to the illuminating device of the present invention, the light combining unit is disposed on the first light source device side when viewed along the direction orthogonal to the reference plane, and at an angle of approximately 45 ° with respect to the illumination optical axis. A first polarization separation / combination unit having a first polarization separation / combination surface disposed; disposed on the second light source device side; disposed at an angle of approximately 45 ° with respect to the illumination optical axis; and the first polarization separation / synthesis A second polarization separation / combination unit having a second polarization separation / combination surface disposed substantially perpendicular to the surface, a reflection mirror disposed on a side opposite to a direction in which the light synthesis unit emits light, a reflection mirror, and the first polarization Since it has a λ / 4 plate disposed between the separation / synthesis unit and the second polarization separation / synthesis unit, the light emitted from the first light source device and the light emitted from the second light source device in the light synthesis unit Are combined into a pair of light source devices, a first light source device and a second light source device. The light emitted is, so that the incident on substantially the same area in the first lens array. For this reason, it is an illuminating device that can be suitably used for a high-intensity projector, and even if the light emission of any one of the pair of light source devices is weakened or cut off, the in-plane light intensity distribution in the illuminated region It is possible to suppress the non-uniformity of the illumination device and to suppress the deterioration of the quality of the projected image.

[2] In the illumination device of the present invention, the first polarization separation / combination surface transmits light composed of one polarization and reflects light composed of the other polarization. One of the light emitted from the first light source device when the light comprising the other polarized light is reflected and the light comprising the other polarized light is allowed to pass, and the reflection mirror and the λ / 4 plate are used as a polarization conversion reflecting portion. After the light having the polarized light passes through the first polarization separation / synthesis surface, the light is reflected by the second polarization separation / synthesis surface toward the first lens array and is emitted from the first light source device. The light composed of the other polarized light is reflected by the first polarization separation / combination surface toward the polarization conversion reflection unit, and then directed to the first lens array as light composed of one polarization by the polarization conversion reflection unit. Reflected from the second light source device After being reflected toward the polarization conversion reflection unit by the second polarization separation / synthesis surface, the light composed of one of the light emitted from the light is converted into light composed of the other polarization by the polarization conversion reflection unit. Of the light reflected toward the first lens array and emitted from the second light source device, the light composed of the other polarized light passes through the second polarization separation / synthesis surface, and then the first polarization separation / synthesis surface. The light reflected toward the first lens array and emitted from the first light source device as light composed of one polarized light and the light emitted from the second light source device as light composed of one polarized light , Incident on substantially the same region in the first lens array, emitted from the first light source device as light composed of the other polarized light, and emitted from the second light source device as light composed of the other polarized light. What is light? It is preferable that the first lens array is incident on substantially the same region.

  With such a configuration, light emitted from each of the first light source device and the second light source device, which are a pair of light source devices, can be incident on substantially the same region in the first lens array. Become.

  Further, by adopting such a configuration, it becomes possible to make the optical path length from the first light source device to the first lens array equal to the optical path length from the second light source device to the first lens array. It is possible to make the in-plane light intensity distribution in the region more uniform.

[3] In the illumination device of the present invention, the first polarization separation / combination surface allows light made of one polarized light to pass through and reflects light made of the other polarization, and the second polarization separation / combination surface is made of one side. One of the light emitted from the first light source device when the light comprising the other polarized light is reflected and the light comprising the other polarized light is allowed to pass, and the reflection mirror and the λ / 4 plate are used as a polarization conversion reflecting portion. After passing through the first polarization separation / combination surface and reflected by the second polarization separation / combination surface toward the polarization conversion reflection unit, the light composed of the polarized light from the other polarization is reflected by the polarization conversion reflection unit. The light that is reflected toward the first lens array as the light and is made of the other polarized light out of the light emitted from the first light source device is directed toward the first lens array on the first polarization separation / synthesis surface. Reflected and emitted from the second light source device Of the emitted light, the light composed of one polarization is reflected toward the first lens array by the second polarization separation / synthesis surface, and the light composed of the other polarization among the light emitted from the second light source device. Passes through the second polarization separation / combination surface and is reflected by the first polarization separation / synthesis surface toward the polarization conversion reflection unit, and then is reflected by the polarization conversion reflection unit as light composed of one polarized light. The light reflected toward one lens array and emitted from the first light source device as light composed of one polarized light and the light emitted from the second light source device as light composed of one polarized light are Light incident on substantially the same region in one lens array and emitted from the first light source device as light composed of the other polarized light and light emitted from the second light source device as light composed of the other polarized light The first len It is preferable that the light is incident on substantially the same region in the array.

  Even with this configuration, it is possible to cause the light emitted from each of the first light source device and the second light source device, which are a pair of light source devices, to enter substantially the same region in the first lens array. It becomes.

[4] In the illumination device according to the present invention, the illumination device further includes a λ / 2 plate disposed between the first polarization separation / combination unit and the second polarization separation / combination unit, The polarization separation / combination surface allows light composed of one polarization to pass and reflects light composed of the other polarization, and the second polarization separation / combination surface allows light composed of one polarization to pass and consists of the other polarization. When reflecting the light and using the reflection mirror and the λ / 4 plate as a polarization conversion reflection unit, the light composed of one of the lights emitted from the first light source device is the first polarization separation / synthesis surface. And is converted to light composed of the other polarized light by the λ / 2 plate, reflected toward the first lens array by the second polarization separation / synthesis surface, and emitted from the first light source device. The light composed of the other polarized light is the first polarized light separating and combining surface. After being reflected toward the light conversion reflection unit, the polarization conversion reflection unit reflects one of the polarized light toward the first lens array and emits one of the light emitted from the second light source device. After passing through the second polarization separation / combination surface and converted to light composed of the other polarization by the λ / 2 plate, the light composed of the polarized light of the first direction is applied to the first lens array on the first polarization separation / combination surface. The light that is reflected toward and is made of the other polarized light out of the light emitted from the second light source device is reflected toward the polarization conversion reflection unit on the second polarization separation / synthesis surface, and then the polarization conversion reflection. The light reflected from the first light source device as light composed of one polarized light and emitted from the first light source device as light composed of one polarized light, and from the second light source device from the other polarized light. Shoot as light The emitted light is incident on substantially the same region in the first lens array, is emitted from the first light source device as light composed of the other polarized light, and is composed of one polarized light from the second light source device. The light emitted as light is preferably incident on substantially the same region in the first lens array.

  Even with this configuration, it is possible to cause the light emitted from each of the first light source device and the second light source device, which are a pair of light source devices, to enter substantially the same region in the first lens array. It becomes.

  Further, by adopting such a configuration, it becomes possible to make the optical path length from the first light source device to the first lens array equal to the optical path length from the second light source device to the first lens array. It is possible to make the in-plane light intensity distribution in the region more uniform.

  In addition, since it further includes a λ / 2 plate disposed between the first polarization separation / synthesis unit and the second polarization separation / synthesis unit, the polarization separation / synthesis characteristics of the first polarization separation / synthesis surface and the second polarization separation / synthesis surface As a result, the in-plane light intensity distribution in the illuminated region can be made more uniform.

  In this case, it is preferable that the first polarization separation / synthesis surface and the second polarization separation / synthesis surface pass light composed of p-polarized light and reflect light composed of s-polarized light. With such a configuration, light composed of s-polarized light is generally reflected more easily than light composed of p-polarized light, so that it is possible to increase the light use efficiency of the lighting device.

[5] In the illumination device of the present invention, the illumination device further includes a λ / 2 plate disposed between the first polarization separation / combination unit and the second polarization separation / combination unit, The polarization separation / combination surface allows light composed of one polarization to pass and reflects light composed of the other polarization, and the second polarization separation / combination surface allows light composed of one polarization to pass and consists of the other polarization. When reflecting the light and using the reflection mirror and the λ / 4 plate as a polarization conversion reflection unit, the light composed of one of the lights emitted from the first light source device is the first polarization separation / synthesis surface. And is converted into light composed of the other polarized light by the λ / 2 plate and reflected toward the polarization conversion reflection unit by the second polarization separation / synthesis surface, and then is reflected by the polarization conversion reflection unit on one side. Reflected to the first lens array as polarized light, Of the light emitted from the first light source device, the light composed of the other polarized light is reflected toward the first lens array by the first polarization separation / synthesis surface, and the light emitted from the second light source device. The light composed of one polarized light passes through the second polarization separation / combination surface, is converted into light composed of the other polarization by the λ / 2 plate, and is converted to the polarization conversion reflection unit by the first polarization separation / combination surface. After being reflected toward the first lens array, the light that is reflected toward the first lens array by the polarization conversion reflection unit and emitted from the second light source device. Is reflected from the second polarization separation / combination surface toward the first lens array, and is emitted from the first light source device as light composed of one polarization, and from the second polarization from the second light source device. And light emitted as light Is incident on substantially the same region in the first lens array and is emitted from the first light source device as light composed of the other polarized light and emitted from the second light source device as light composed of the one polarized light. It is preferable that the incident light enters substantially the same region in the first lens array.

  Even with this configuration, it is possible to cause the light emitted from each of the first light source device and the second light source device, which are a pair of light source devices, to enter substantially the same region in the first lens array. It becomes.

  In addition, since it further includes a λ / 2 plate disposed between the first polarization separation / synthesis unit and the second polarization separation / synthesis unit, the polarization separation / synthesis characteristics of the first polarization separation / synthesis surface and the second polarization separation / synthesis surface As a result, the in-plane light intensity distribution in the illuminated region can be made more uniform.

  In this case, it is preferable that the first polarization separation / synthesis surface and the second polarization separation / synthesis surface pass light composed of p-polarized light and reflect light composed of s-polarized light. With such a configuration, light composed of s-polarized light is generally reflected more easily than light composed of p-polarized light, so that it is possible to increase the light use efficiency of the lighting device.

[6] In the illumination device of the present invention, it is preferable that the first polarization separation / combination unit and the second polarization separation / combination unit include a prism-type polarization beam splitter.

[7] In the illumination device of the present invention, it is preferable that the first polarization separation / combination unit and the second polarization separation / combination unit include a wire grid type polarizing plate.

  As described above, in the illumination device of the present invention, the first polarization separation / combination unit and the second polarization separation / combination unit made of the prism type PBS are also the first polarization separation / combination unit and the first polarization separation / combination unit made of the wire grid type polarization plate. Both two-polarized light separation / combination sections can also be used suitably.

[8] In the illumination device of the present invention, when viewed along a direction orthogonal to the reference plane, an angle between the optical axis of the first light source device and the illumination optical axis is R1, and the second When the angle between the optical axis of the light source device and the illumination optical axis is R2, the first light source device and the second light source device are “R1 = R2” and “R1 <90 °”. Light emitted from the first light source device as light having one polarization, light emitted from the first light source device as light having the other polarization, and one polarization from the second light source device. It is preferable that the light emitted as light composed of the light and the light emitted as light composed of the other polarized light from the second light source device enter substantially the same region in the first lens array.

  By adopting such a configuration, since all the light emitted from the pair of light source devices is incident on substantially the same region (single region) in the first lens array, it becomes possible to improve the light utilization efficiency. In addition, the in-plane light intensity distribution in the illuminated area can be made more uniform. In addition, the area of the first lens array can be reduced, and the entire illumination device can be reduced in size.

[9] In the illumination device of the present invention, when the first light source device and the second light source device are a pair of light source devices, the illumination device preferably includes two or more pairs of light source devices.

  With such a configuration, it is possible to obtain a lighting device with higher brightness.

[10] A projector of the present invention projects the illumination device of the present invention, a light modulation device that modulates illumination light from the illumination device according to image information, and modulated light from the light modulation device as a projection image. And a projection optical system.

  For this reason, according to the projector of the present invention, since the illumination device of the present invention as described above is provided, the projector has a high brightness, and the light emission of any one of the pair of light source devices is weak. The projector can suppress the deterioration of the quality of the projected image even if it is broken or broken.

FIG. 3 is a top view showing an optical system of the projector 1000 according to the first embodiment. The figure shown in order to demonstrate the photosynthesis part 30 in Embodiment 1. FIG. FIG. 6 is a top view showing a photosynthesis unit 30a in Comparative Example 1. The figure which shows how the light inject | emitted from the 1st light source device 10 and the light inject | emitted from the 2nd light source device 20 inject into the 1st lens array 120 in the illuminating device 100a which concerns on the comparative example 1. FIG. FIG. 4 is a diagram showing how light emitted from the first light source device 10 and light emitted from the second light source device 20 enter the first lens array 120 in the illumination device 100 according to the first embodiment. FIG. 6 is a top view showing a light combining unit 32 in the second embodiment. FIG. 6 is a top view showing a light combining unit in Embodiment 3. FIG. 6 is a top view showing a light combining unit 36 according to Embodiment 4. FIG. 10 is a perspective view of first light source devices 10 and 11, second light source devices 20 and 21, and light combining units 30 and 31 in Embodiment 5. In the illumination device 108 according to the fifth embodiment, how the light emitted from the first light source devices 10 and 11 and the light emitted from the second light source devices 20 and 21 enter the first lens array 128. FIG. The figure shown in order to demonstrate the illuminating device 109 which concerns on Embodiment 6. FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an illumination device and a projector of the present invention will be described based on embodiments shown in the drawings.

[Embodiment 1]
FIG. 1 is a top view showing an optical system of a projector 1000 according to the first embodiment.
FIG. 2 is a diagram for explaining the light combining unit 30 according to the first embodiment. 2A is a top view of the light combining unit 30, and FIG. 2B is a perspective view of the first light source device 10, the second light source device 20, and the light combining unit 30.
In FIG. 1 and FIG. 2, illustration of an attachment portion and the like for attaching the components shown in the drawings to the housing is omitted. The same applies to the other drawings.
In FIG. 2A, symbol L1 indicates light emitted from the first light source device 10, and symbol L1 (p) indicates light composed of p-polarized light out of the light emitted from the first light source device 10. , L1 (s) indicates light composed of s-polarized light among the light emitted from the first light source device 10, and L1 (s → p) represents light derived from s-polarized light among the light emitted from the first light source device 10. The light L converted from p-polarized light to light composed of p-polarized light, L2 represents light emitted from the second light source device 20, and L2 (p) represents light emitted from the second light source device 20. p2 indicates light composed of p-polarized light, L2 (s) indicates light composed of s-polarized light emitted from the second light source device 20, and L2 (p → s) indicates light emitted from the second light source device 20. Shows light converted from p-polarized light to s-polarized light. . The same applies to the other drawings. Further, the locus of light emitted from the first light source device 10 such as L1 and L1 (p) is indicated by a solid arrow, and the locus of light emitted from the second light source device 20 such as L2 and L2 (p) is indicated by a dotted arrow. Show. The same applies to FIGS. 6 to 8 described later.

First, configurations of the illumination device 100 and the projector 1000 according to the first embodiment will be described.
As shown in FIG. 1, the projector 1000 according to the first embodiment includes an illumination device 100, a color separation light guide optical system 200, three liquid crystal light modulation devices 400R, 400G, and 400B as light modulation devices, and a cross A dichroic prism 500 and a projection optical system 600 are provided.

  The illumination device 100 includes a first light source device 10, a second light source device 20, a light combining unit 30, and a lens integrator optical system 110.

  The first light source device 10 and the second light source device 20 are a pair of light source devices that are disposed substantially opposite to each other.

  The first light source device 10 includes an arc tube 12 and a parabolic reflector 14. The first light source device 10 emits parallel light along the optical axis 10ax of the first light source device.

  The arc tube 12 has a tube bulb portion and a pair of sealing portions extending on both sides of the tube bulb portion. Although the detailed description by illustration is abbreviate | omitted, a tube part has a pair of electrode arrange | positioned in a tube part, mercury, a noble gas, and a small amount of halogens. When a potential difference is generated between the pair of electrodes, discharge is generated and an arc image is generated. This arc image is a light emitting part, and is located in the vicinity of the focal point of the parabolic reflector 14. The tube portion is made of, for example, quartz glass. As the arc tube 14, various arc tubes that emit light with high luminance can be adopted, and for example, a metal halide lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, or the like can be adopted.

  The ellipsoidal reflector 14 has an opening through which one sealing portion of the arc tube 14 is inserted and fixed, and a reflection surface that reflects light from the arc tube 14 as parallel light.

The second light source device 20 includes an arc tube 22 and a parabolic reflector 24. The second light source device 20 emits parallel light along the illumination optical axis 20ax.
Since the arc tube 22 has the same configuration as the arc tube 12 and the paraboloid reflector 24 has the same configuration as the paraboloid reflector 14, the description thereof is omitted.

  As shown in FIGS. 1 and 2, the light combining unit 30 is disposed between the first light source device 10 and the second light source device 20, and emits light emitted from the first light source device 10 and the second light source device 20. The emitted light is synthesized and emitted toward a predetermined direction (lens integrator optical system 110). As shown in FIG. 2, the light combining unit 30 includes a first polarization separation / combination unit 40, a second polarization separation / combination unit 50, a reflection mirror 62, and a λ / 4 plate 64.

  The first polarization separation / combination unit 40 has a plane parallel to all of the optical axis 10ax of the first light source device 10, the optical axis 20ax of the second light source device 20 and the illumination optical axis 100ax as a reference plane. When viewed along the direction orthogonal to the reference plane, the first light source device 10 side is provided, and the first polarization separation / synthesis surface 48 is disposed at an angle of about 45 ° with respect to the illumination optical axis 100ax. The first polarization separation / combination unit 40 includes a prism-type polarization beam splitter (hereinafter, the polarization beam splitter is referred to as PBS in this specification). The first polarization separation / combination surface 48 transmits light composed of p-polarized light and reflects light composed of s-polarized light. The first polarization separation / synthesis surface 48 is made of a dielectric multilayer film.

  The second polarization separation / combination unit 50 is disposed on the second light source device 20 side when viewed along the direction orthogonal to the reference plane, is disposed at an angle of approximately 45 ° with respect to the illumination optical axis 100ax, and The second polarization separation / synthesis surface 58 is disposed substantially perpendicular to the first polarization separation / synthesis surface 48. The second polarization separation / combination unit 50 is composed of a prism type PBS. The second polarization separation / combination surface 58 reflects light composed of p-polarized light and allows light composed of s-polarized light to pass therethrough. The second polarization separation / synthesis surface 58 is made of a dielectric multilayer film.

  As shown in FIG. 2A, the first polarization separation / synthesis surface 48 and the second polarization separation / synthesis surface 58 are arranged in a so-called valley shape (V-shape).

The reflection mirror 62 is disposed on the opposite side to the direction in which the light combining unit 30 emits light (the direction of the lens integrator optical system 110). The reflection mirror 62 is a mirror that reflects visible light, and has a reflection surface on the side from which the light combining unit 30 emits light.
The λ / 4 plate 64 is disposed between the reflection mirror 62 and the first polarization separation / combination unit 40 and the second polarization separation / combination unit 50.
The reflection mirror 62 and the λ / 4 plate 64 constitute a polarization conversion reflection unit 60. The light incident on the polarization conversion reflection unit 60 is reflected after the polarization direction is converted. That is, the p-polarized light incident on the polarization conversion reflection unit 60 is reflected as s-polarized light, and the s-polarized light incident on the polarization conversion reflection unit 60 is reflected as p-polarization light.

  Here, the locus of light in the light combining unit 30 will be mainly described with reference to FIG.

The light L1 emitted from the first light source device 10 is first separated into light composed of p-polarized light and light composed of s-polarized light by the first polarization separation / synthesis surface 48.
Of the light emitted from the first light source device 10, the light L <b> 1 (p) composed of p-polarized light passes through the first polarization separation / combination surface 48, and then passes through the first lens array 120 (described later) on the second polarization separation / combination surface 58. ) Is reflected toward.
Of the light emitted from the first light source device 10, the light L <b> 1 (s) composed of s-polarized light is reflected toward the polarization conversion reflection unit 60 by the first polarization separation / synthesis surface 48, and then is reflected by the polarization conversion reflection unit 60. The light L1 (s → p) composed of one polarized light is reflected toward the first lens array 120.

The light L2 emitted from the second light source device 20 is first separated into light composed of p-polarized light and light composed of s-polarized light by the second polarization separation / combination surface 58.
Of the light emitted from the second light source device 20, the light L <b> 2 (p) composed of p-polarized light is reflected toward the polarization conversion reflection unit 60 by the second polarization separation / synthesis surface 58, and then is reflected by the polarization conversion reflection unit 60. , S-polarized light L2 (p → s) is reflected toward the first lens array 120.
Of the light emitted from the second light source device 20, the light L <b> 2 (s) composed of s-polarized light passes through the second polarization separation / synthesis surface 58, and then is directed to the first lens array 120 on the first polarization separation / synthesis surface 48. And reflected.

  At this time, light L1 (p) composed of p-polarized light out of the light emitted from the first light source device 10 and s-polarized light from light L2 (p) composed of p-polarized light out of the light emitted from the second light source device 20. The light L2 (p → s) converted into the light consisting of is synthesized by the second polarization separation / synthesis surface 58. The light L1 (s → p) converted from the light L1 (s) composed of s-polarized light to the light composed of p-polarized light out of the light emitted from the first light source device 10 and emitted from the second light source device 20. The light L2 (s) composed of s-polarized light is synthesized by the first polarization separation / synthesis surface 48.

  The lens integrator optical system 110 has a function of making the in-plane light intensity distribution of the light from the light combining unit 30 uniform. The lens integrator optical system 110 includes a first lens array 120, a second lens array 130, a polarization conversion element 140, and a superimposing lens 150.

  The first lens array 120 includes a plurality of first small lenses 122 for dividing the light from the light combining unit 30 into a plurality of partial light beams. The first lens array 120 has a function as a light beam splitting optical element that splits light from the light combining unit 30 into a plurality of partial light beams, and the plurality of first small lenses 122 are in a plane orthogonal to the illumination optical axis 100ax. It has a configuration arranged in a matrix of multiple rows and multiple columns. Although not illustrated, the outer shape of the first small lens 122 is substantially similar to the outer shape of the image forming region of the liquid crystal light modulators 400R, 400G, and 400B.

As shown in FIG. 5 to be described later, the first lens array 120 has light L1 (p) emitted as light composed of p-polarized light from the first light source device 10 and light composed of p-polarized light from the second light source device 20. The light L2 (p → s) converted from the light L2 (p) emitted as s-polarized light is incident on substantially the same region.
The first lens array 120 includes light L1 (s → p) converted from light L1 (s) emitted from the first light source device 10 as light composed of s-polarized light into light composed of p-polarized light, and first light Light L <b> 2 (s) emitted as light composed of s-polarized light from the two light source devices 20 enters substantially the same region.
That is, the light emitted from the first light source device 10 and the light emitted from the second light source device 20 are incident on substantially the same region in the first lens array 120.

  2A, the optical path length of light emitted from the first light source device 10 in the light combining unit 30 and the optical path length of light emitted from the second light source device 20 in the light combining unit 30 are as follows. Therefore, the optical path length from the first light source device 10 to the first lens array 120 is equal to the optical path length from the second light source device 20 to the first lens array 120.

  The second lens array 130 has a plurality of second small lenses 132 corresponding to the plurality of first small lenses 122 of the first lens array 120. The second lens array 130 has a function of forming an image of each first small lens 122 of the first lens array 120 in the vicinity of the image forming area of the liquid crystal light modulators 400R, 400G, and 400B together with the superimposing lens 150. The second lens array 130 has a configuration in which a plurality of second small lenses 132 are arranged in a matrix of a plurality of rows and a plurality of columns in a plane orthogonal to the illumination optical axis 100ax.

The polarization conversion element 140 is a polarization conversion element that emits the polarization direction of each of the partial light beams divided by the first lens array 120 as light composed of substantially one type of linearly polarized light having the same polarization direction.
The polarization conversion element 140 transmits one linearly polarized component (for example, p-polarized component) among the polarized components included in the light from the second lens array 130 as it is, and the other linearly polarized component (for example, s-polarized component). Is reflected in the direction perpendicular to the illumination optical axis 100ax, the reflective layer that reflects the other linearly polarized light component reflected in the polarization separation layer in the direction parallel to the illumination optical axis 100ax, and the reflective layer. And a phase difference plate that converts the other linearly polarized light component into one linearly polarized light component.

  The superimposing lens 150 superimposes each partial light beam from the polarization conversion element 140 in the illuminated area. The superimposing lens 150 is an optical element for condensing the partial light beam and superimposing it on the vicinity of the image forming area of the liquid crystal light modulators 400R, 400G, and 400B. The superimposing lens 150 is arranged so that the optical axis of the superimposing lens 150 and the illumination optical axis 100ax substantially coincide. The superimposing lens 150 may be composed of a compound lens in which a plurality of lenses are combined.

The color separation light guide optical system 200 includes dichroic mirrors 210 and 220, reflection mirrors 230, 240 and 250, and relay lenses 260 and 270. The color separation light guide optical system 200 separates the light from the illumination device 100 into red light, green light, and blue light, and each color light of red light, green light, and blue light is an illumination target. It has a function of guiding light to 400R, 400G, and 400B.
Condensing lenses 300R, 300G, and 300B are disposed between the color separation light guide optical system 200 and the liquid crystal light modulation devices 400R, 400G, and 400B.

The dichroic mirrors 210 and 220 are mirrors in which a wavelength selective transmission film that reflects light in a predetermined wavelength region and passes light in other wavelength regions is formed on a substrate.
The dichroic mirror 210 is a dichroic mirror that reflects a red light component and transmits green light and blue light components.
The dichroic mirror 220 is a dichroic mirror that reflects a green light component and transmits a blue light component.
The reflection mirror 230 is a reflection mirror that reflects a red light component.
The reflection mirrors 240 and 250 are reflection mirrors that reflect blue light components.

The red light reflected by the dichroic mirror 210 is reflected by the reflection mirror 230, passes through the condenser lens 300R, and enters the image forming area of the liquid crystal light modulator 400R for red light.
The green light that has passed through the dichroic mirror 210 is reflected by the dichroic mirror 220, passes through the condenser lens 300G, and enters the image forming area of the liquid crystal light modulator 400G for green light.
The blue light that has passed through the dichroic mirror 220 passes through the relay lens 260, the incident-side reflecting mirror 240, the relay lens 270, the exit-side reflecting mirror 250, and the condensing lens 300B, and the image of the liquid crystal light modulator 400B for blue light. Incident into the formation area. The relay lenses 260 and 270 and the reflection mirrors 240 and 250 have a function of guiding the blue light component transmitted through the dichroic mirror 220 to the liquid crystal light modulation device 400B.

  The reason why such a relay lens 260, 270 is provided in the optical path of blue light is that the length of the optical path of blue light is longer than the length of the optical path of other color light, This is to prevent a decrease in usage efficiency. The projector 1000 according to the first embodiment has such a configuration because the length of the optical path of blue light is long. However, the length of the optical path of red light is increased, and the relay lenses 260 and 270 and the reflection mirror are configured. A configuration using 240 and 250 in the optical path of red light is also conceivable.

The liquid crystal light modulators 400R, 400G, and 400B modulate incident color light in accordance with image information to form a color image, and are illumination targets of the illumination device 100. Although not shown, an incident-side polarizing plate is interposed between the condenser lenses 300R, 300G, and 300B and the liquid crystal light modulators 400R, 400G, and 400B, and the liquid crystal light modulators are arranged. Between the devices 400R, 400G, and 400B and the cross dichroic prism 500, exit-side polarizing plates are respectively disposed. The incident-side color light is modulated by the incident-side polarizing plate, the liquid crystal light modulators 400R, 400G, and 400B and the exit-side polarizing plate.
The liquid crystal light modulators 400R, 400G, and 400B are transmissive liquid crystal light modulators in which a liquid crystal that is an electro-optical material is hermetically sealed in a pair of transparent glass substrates. For example, a polysilicon TFT is used as a switching element. In accordance with a given image signal, the polarization direction of one type of linearly polarized light emitted from the incident side polarizing plate is modulated.

  The cross dichroic prism 500 is an optical element that forms a color image by synthesizing an optical image modulated for each color light emitted from the emission side polarizing plate. The cross dichroic prism 500 has a substantially square shape in plan view in which four right-angle prisms are bonded together, and a dielectric multilayer film is formed on a substantially X-shaped interface in which the right-angle prisms are bonded together. The dielectric multilayer film formed at one of the substantially X-shaped interfaces reflects red light, and the dielectric multilayer film formed at the other interface reflects blue light. By these dielectric multilayer films, the red light and the blue light are bent and aligned with the traveling direction of the green light, so that the three color lights are synthesized.

  The color image emitted from the cross dichroic prism 500 is enlarged and projected by the projection optical system 600 to form an image on the screen SCR.

  Next, effects of the illumination device 100 and the projector 1000 according to the first embodiment will be described.

  The illumination device 100 according to the first embodiment includes the first light source device 10 and the second light source device 20 and the light combining unit 30 that are disposed substantially opposite to each other, and the light combining unit 30 is in a direction orthogonal to the reference plane. When viewed along, the first polarization separation / combination unit 40 having the first polarization separation / synthesis surface 48 disposed on the first light source device 10 side and disposed at an angle of approximately 45 ° with respect to the illumination optical axis 100ax. And a second polarization separation / combination surface disposed on the second light source device 20 side, disposed at an angle of approximately 45 ° with respect to the illumination optical axis 100ax, and disposed substantially perpendicular to the first polarization separation / combination surface 48. 58, a second polarization separation / combination unit 50, a reflection mirror 62 disposed on the opposite side of the direction in which the light synthesis unit 30 emits light, a reflection mirror 62, a first polarization separation / combination unit 40, and a second polarization separation. Λ / arranged between the combining unit 50 Since the plate 64 is included, the light emitted from the first light source device 10 and the light emitted from the second light source device 20 are synthesized by the light combining unit 30 and the first light source device 10 which is a pair of light source devices. The light emitted from each of the light source device 20 and the second light source device 20 is incident on substantially the same region in the first lens array 120, and is a lighting device that can be suitably used for a high-intensity projector. Even if the light emission of any one of the light source devices is weakened or cut off, it is possible to suppress the in-plane light intensity distribution in the illuminated area from being uneven and to deteriorate the quality of the projected image It becomes an illuminating device which can suppress doing.

  Further, according to the illumination device 100 according to the first embodiment, the first polarization separation / combination surface 48 transmits light composed of p-polarized light, reflects light composed of s-polarization, and the second polarization separation / combination surface 58 includes: The p-polarized light is reflected, the s-polarized light is allowed to pass, and the p-polarized light L1 (p) out of the light emitted from the first light source device 10 passes through the first polarization separation / synthesis surface 48. After that, the light L1 (s) composed of s-polarized light out of the light emitted from the first light source device 10 is reflected toward the first lens array 120 (described later) by the second polarization separation / combination surface 58. After being reflected toward the polarization conversion reflection unit 60 by the polarization separation / combination surface 48, the polarization conversion reflection unit 60 reflects the light L1 (s → p) of one polarization toward the first lens array 120, P of the light emitted from the second light source device 20 The light L2 (p) composed of light is reflected toward the polarization conversion reflection unit 60 by the second polarization separation / synthesis surface 58, and then is converted into light L2 (p → s) composed of s-polarized light by the polarization conversion reflection unit 60. Of the light reflected toward the first lens array 120 and emitted from the second light source device 20, the light L <b> 2 (s) composed of s-polarized light passes through the second polarization separation / combination surface 58, and then the first polarization separation. Since the light is reflected toward the first lens array 120 by the combining surface 48, the light emitted from each of the first light source device 10 and the second light source device 20 that are a pair of light source devices is reflected in the first lens array 120. Incident light can be incident on substantially the same region.

  Moreover, according to the illuminating device 100 which concerns on Embodiment 1, the optical path length from the 1st light source device 10 to the 1st lens array 120 and the optical path length from the 2nd light source device 20 to the 1st lens array 120 are made equal. Accordingly, the in-plane light intensity distribution in the illuminated area can be made more uniform.

  Since the projector 1000 according to the first embodiment includes the excellent illumination device of the present invention as described above, it is a high-intensity projector, and the light emission of any one of the pair of light source devices is weak. The projector can suppress the deterioration of the quality of the projected image even if it is broken or broken.

[Comparative Example 1]
Next, the effect of the illumination device according to the present invention will be described using a comparative example.

FIG. 3 is a top view showing the photosynthesis unit 30a in the first comparative example.
FIG. 4 shows how the light emitted from the first light source device 10 and the light emitted from the second light source device 20 enter the first lens array 120 in the illumination device 100a according to Comparative Example 1. FIG. 4A is a diagram when both the first light source device 10 and the second light source device 20 are lit, and FIG. 4B is a diagram when only the first light source device 10 is lit. FIG.
FIG. 5 illustrates how the light emitted from the first light source device 10 and the light emitted from the second light source device 20 enter the first lens array 120 in the illumination device 100 according to the first embodiment. FIG. FIG. 5A is a diagram when both the first light source device 10 and the second light source device 20 are lit, and FIG. 5B is a diagram when only the first light source device 10 is lit. FIG.
4 and 5, a region indicated by gray indicates a region where light is incident on the first lens array 120. The same applies to FIGS. 10 and 11B described later.

The lighting device 100a (not shown) according to the comparative example 1 basically has the same configuration as the lighting device 100 according to the first embodiment, but the configuration of the light combining unit is the same as that of the lighting device 100 according to the first embodiment. Is different. That is, the illuminating device 100a which concerns on the comparative example 1 is provided with the photosynthesis part 30a shown in FIG. The light combining unit 30a includes a triangular prism that combines light from a pair of light source devices.
When viewed along a direction orthogonal to the reference plane, the light combining unit 30a is disposed on the first light source device 10 side and disposed at an angle of approximately 45 ° with respect to the illumination optical axis; The second light source device 20 is disposed on the second light source device 20 side, is disposed at an angle of approximately 45 ° with respect to the illumination optical axis 100ax, and has a second reflection surface 58a disposed substantially perpendicular to the first polarization separation / synthesis surface 48. .

  In the illumination device 100a, the light L1 emitted from the first light source device 10 is reflected toward the first lens array 120 by the first polarization separation / synthesis surface 48a. The light L2 emitted from the second light source device 20 is reflected toward the first lens array 120 by the second polarization separation / synthesis surface 58.

In the illumination device 100a according to the comparative example 1, as shown in FIG. 4A, the light emitted from the first light source device 10 and the light emitted from the second light source device 20 are the first lens array. In 120, it injects into a mutually different area | region (refer the area | region shown with the code | symbol L1, and the area | region shown with the code | symbol L2). In this case, when the light emission of any one of the pair of light source devices (for example, the second light source device 20) is weakened or cut off, the light enters the first lens array 120 as shown in FIG. 4B. The light is biased.
For this reason, in the illuminating device 100a which concerns on the comparative example 1, when the light emission of either light source device among a pair of light source devices weakens or cuts out, the in-plane light intensity distribution in the illuminated area becomes non-uniform. The quality of the projected image deteriorates.

On the other hand, in the illumination device 100 according to the first embodiment, as shown in FIG. 5A, the light emitted from the first light source device 10 and the light emitted from the second light source device 20 In the first lens array 120, the light is incident on substantially the same region (refer to the region indicated by reference signs L1 (s → p) and L2 (s) and the region indicated by reference signs L1 (p) and L2 (p → s)). ). In this case, even if the light emission of any one of the pair of light source devices is weakened or cut off, the light incident on the first lens array 120 is not biased as shown in FIG. 5B.
For this reason, the illumination device 100 according to Embodiment 1 has a non-uniform in-plane light intensity distribution in the illuminated region even if the light emission of any one of the pair of light source devices is weakened or cut off. It is possible to suppress the deterioration of the quality of the projected image.

[Embodiment 2]
FIG. 6 is a top view illustrating the light combining unit 32 according to the second embodiment.
In FIG. 6, reference symbol L <b> 1 (p → s) indicates light converted from p-polarized light to s-polarized light among the light emitted from the first light source device 10, and reference symbol L <b> 2 (s → p) indicates light converted from s-polarized light to p-polarized light out of the light emitted from the second light source device 20. The same applies to the other drawings.
In FIG. 6, the same members as those in FIG. 2A are denoted by the same reference numerals, and detailed description thereof is omitted.

  The illumination device 102 (not shown) according to the second embodiment basically has the same configuration as that of the illumination device 100 according to the first embodiment, but the direction of the polarization separation reflection surface is the illumination device according to the first embodiment. 100 is different. That is, the first polarization separation / synthesis surface 48 and the second polarization separation / synthesis surface 58 in the second embodiment are arranged in a so-called mountain shape as shown in FIG.

The first polarization separation / combination unit 42 is disposed on the first light source device 10 side when viewed along a direction orthogonal to the reference plane, and has an angle of approximately 45 ° with respect to the illumination optical axis 102ax (not shown). The first polarization separation / synthesis surface 48 is disposed at The first polarization separation / combination unit 42 is composed of a prism type PBS.
The second polarization separation / combination unit 52 is disposed on the second light source device 20 side when viewed along the direction orthogonal to the reference plane, is disposed at an angle of approximately 45 ° with respect to the illumination optical axis 102ax, and The second polarization separation / synthesis surface 58 is disposed substantially perpendicular to the first polarization separation / synthesis surface 48. The second polarization separation / combination unit 52 is formed of a prism type PBS.

  Here, the trajectory of light in the light combining unit 32 will be mainly described with reference to FIG.

The light L1 emitted from the first light source device 10 is first separated into light composed of p-polarized light and light composed of s-polarized light by the first polarization separation / synthesis surface 48.
Of the light emitted from the first light source device 10, the light L <b> 1 (p) composed of p-polarized light passes through the first polarization separation / combination surface 48 and is directed toward the polarization conversion reflection unit 60 by the second polarization separation / synthesis surface 58. After being reflected, the light is reflected toward the first lens array 120 as light L1 (p → s) composed of s-polarized light by the polarization conversion reflection unit 60.
Of the light emitted from the first light source device 10, the light L <b> 1 (s) composed of s-polarized light is reflected toward the first lens array 120 by the first polarization separation / synthesis surface 48.

The light L2 emitted from the second light source device 20 is first separated into light composed of p-polarized light and light composed of s-polarized light by the second polarization separation / combination surface 58.
Of the light emitted from the second light source device 20, the light L <b> 2 (p) composed of p-polarized light is reflected toward the first lens array 120 by the second polarization separation / synthesis surface 58.
Of the light emitted from the second light source device 20, the light L <b> 2 (s) composed of s-polarized light passes through the second polarization separation / synthesis surface 58 and is directed toward the polarization conversion reflection unit 60 on the first polarization separation / synthesis surface 48. After being reflected, the light is reflected toward the first lens array 120 as light L2 (s → p) composed of p-polarized light by the polarization conversion reflection unit 60.

  At this time, out of the light emitted from the first light source device 10, the light L <b> 1 (p → s) converted from the light L <b> 1 (p) composed of p-polarized light to the light composed of s-polarized light, and the light emitted from the second light source device 20. The light L <b> 2 (p) composed of p-polarized light is synthesized by the second polarization separation / synthesis surface 58. Further, the light L1 (s) composed of s-polarized light out of the light emitted from the first light source device 10 and the light L2 (s) composed of s-polarized light out of the light emitted from the second light source device 20 from p-polarized light. The light L <b> 2 (s → p) converted into the resulting light is synthesized by the first polarization separation / synthesis surface 48.

The first lens array 120 (not shown) includes light L1 (p →) converted from light L1 (p) composed of p-polarized light to light composed of s-polarized light out of the light emitted from the first light source device 10. s) and light L2 (p) made of p-polarized light out of the light emitted from the second light source device 20 enter substantially the same region.
Further, the first lens array 120 includes light L1 (s) composed of s-polarized light out of the light emitted from the first light source device 10 and light composed of s-polarized light out of the light emitted from the second light source device 20. Light L2 (s → p) converted from L2 (s) to light composed of p-polarized light is incident on substantially the same region.
That is, the light emitted from the first light source device 10 and the light emitted from the second light source device 20 are incident on substantially the same region in the first lens array 120.

  As described above, the illuminating device 102 according to the second embodiment is different from the illuminating device 100 according to the first embodiment in the direction of the polarization separating / reflecting surface, but the first light source device 10 and the second light source device 10 that are disposed substantially opposite to each other. A light source device 20 and a light combining unit 32 are provided, and the light combining unit 32 is disposed on the first light source device 10 side when viewed along a direction orthogonal to the reference plane and is approximately 45 with respect to the illumination optical axis 102ax. The first polarization separation / combination unit 42 having the first polarization separation / synthesis surface 48 arranged at an angle of ° and the second light source device 20 side are arranged at an angle of about 45 ° with respect to the illumination optical axis 102ax. And a second polarization separation / combination unit 52 having a second polarization separation / combination surface 58 arranged substantially perpendicular to the first polarization separation / combination surface 48, and a direction opposite to the direction in which the light synthesis unit 32 emits light. Reflection mirror 62 and reflection mirror 6 2 and the λ / 4 plate 64 disposed between the first polarization separation / combination unit 42 and the second polarization separation / combination unit 52, the light synthesis unit 32 as in the illumination device 100 according to the first embodiment. The light emitted from the first light source device 10 and the light emitted from the second light source device 20 are combined and emitted from each of the first light source device 10 and the second light source device 20 which are a pair of light source devices. The illumination light is incident on substantially the same region in the first lens array 120 and can be suitably used for a high-brightness projector, and the light emission of any one of the pair of light source devices Illumination device capable of suppressing non-uniform in-plane light intensity distribution in the illuminated area and preventing the quality of the projected image from deteriorating even if the light is weakened or cut off It made.

  The illumination device 102 according to the second embodiment has the same configuration as that of the illumination device 100 according to the first embodiment except for the direction of the polarization separation / reflection surface, and thus the effect of the illumination device 100 according to the first embodiment. Of the relevant effects.

[Embodiment 3]
FIG. 7 is a top view illustrating the light combining unit 34 according to the third embodiment.
In FIG. 7, the same members as those in FIG. 2A are denoted by the same reference numerals, and detailed description thereof is omitted.

  The illumination device 104 (not shown) according to the third embodiment basically has the same configuration as that of the illumination device 100 according to the first embodiment, except that the light combining unit further includes a λ / 2 plate. 1 is different from the illumination device 100 according to 1. Accordingly, the configuration of the second polarization separation / reflection surface is also different. That is, in the illumination device 104 according to the third embodiment, as illustrated in FIG. 7, the light combining unit 34 further includes a λ / 2 plate. The second polarization separation / combination surface 59 is configured to pass light composed of p-polarized light and reflect light composed of s-polarized light.

  The second polarization separation / combination unit 54 is disposed on the second light source device 20 side when viewed along a direction orthogonal to the reference plane, and has an angle of approximately 45 ° with respect to the illumination optical axis 104ax (not shown). And a second polarization separation / synthesis surface 59 arranged substantially perpendicular to the first polarization separation / synthesis surface 48. The second polarization separation / combination unit 54 is made of a prism type PBS. The second polarization separation / synthesis surface 59 is made of a dielectric multilayer film.

  The λ / 2 plate 70 is disposed between the first polarization separation / synthesis unit 40 and the second polarization separation / synthesis unit 54. The λ / 2 plate 70 converts the polarization direction of light passing through the λ / 2 plate 70. That is, if the light passing through the λ / 2 plate 70 is light composed of p-polarized light, it is converted to light composed of s-polarized light, and if light composed of s-polarized light is converted to light composed of p-polarized light.

  Here, the trajectory of light in the light combining unit 34 will be mainly described with reference to FIG.

The light L1 emitted from the first light source device 10 is first separated into light composed of p-polarized light and light composed of s-polarized light by the first polarization separation / synthesis surface 48.
Of the light emitted from the first light source device 10, the light L 1 (p) composed of p-polarized light passes through the first polarization separation / synthesis surface 48, and the light L 1 composed of s-polarized light by the λ / 2 plate 70 (p → s ) Is reflected by the second polarization separation / synthesis surface 59 toward the first lens array 120.
Of the light emitted from the first light source device 10, the light L <b> 1 (s) composed of s-polarized light is reflected toward the polarization conversion reflection unit 60 by the first polarization separation / synthesis surface 48, and then is reflected by the polarization conversion reflection unit 60. , P-polarized light L1 (s → p) is reflected toward the first lens array 120.

The light L2 emitted from the second light source device 20 is first separated into light composed of p-polarized light and light composed of s-polarized light by the second polarization separation / combination surface 58.
Of the light emitted from the second light source device 20, the light L <b> 2 (p) composed of p-polarized light passes through the second polarization separation / combination surface 59, and the light L <b> 2 composed of s-polarized light by the λ / 2 plate 70 (p → s ) Is reflected toward the first lens array 120 by the first polarization separation / synthesis surface 48.
Of the light emitted from the second light source device 20, the light L <b> 2 (s) composed of s-polarized light is reflected toward the polarization conversion reflection unit 60 by the second polarization separation / synthesis surface 59, and then is reflected by the polarization conversion reflection unit 60. , P-polarized light L2 (s → p) is reflected toward the first lens array 120.

  At this time, out of the light emitted from the first light source device 10, the light L <b> 1 (p → s) converted from the light L <b> 1 (p) composed of p-polarized light to the light composed of s-polarized light, and the light emitted from the second light source device 20. The light L 2 (s → p) converted from the light L 2 (s) composed of s-polarized light to the light composed of p-polarized light is synthesized by the second polarization separation / synthesis surface 59. The light L1 (s → p) converted from the light L1 (s) composed of s-polarized light to the light composed of p-polarized light out of the light emitted from the first light source device 10 and emitted from the second light source device 20. The light L 2 (p → s) converted from the light L 2 (p) composed of p-polarized light to the light composed of s-polarized light is synthesized by the first polarization separation / synthesis surface 48.

The first lens array 120 (not shown) includes light L1 (p →) converted from light L1 (p) composed of p-polarized light to light composed of s-polarized light out of the light emitted from the first light source device 10. s) and light L2 (s → p) converted from light L2 (s) composed of s-polarized light to light composed of p-polarized light out of the light emitted from the second light source device 20 in substantially the same region. Incident.
The first lens array 120 includes light L1 (s → p) converted from light L1 (s) composed of s-polarized light to light composed of p-polarized light out of the light emitted from the first light source device 10. Of the light emitted from the second light source device 20, light L2 (p → s) converted from light L2 (p) composed of p-polarized light to light composed of s-polarized light enters substantially the same region.
That is, the light emitted from the first light source device 10 and the light emitted from the second light source device 20 are incident on substantially the same region in the first lens array 120.

  As shown in FIG. 7, the optical path length of the light emitted from the first light source device 10 in the light combining unit 34 is equal to the optical path length of the light emitted from the second light source device 20 in the light combining unit 34. The optical path length from the first light source device 10 to the first lens array 120 is equal to the optical path length from the second light source device 20 to the first lens array 120.

  As described above, the illuminating device 104 according to the third embodiment differs from the illuminating device 100 according to the first embodiment in that the light combining unit further includes a λ / 2 plate and the configuration of the second polarization separation / reflection surface is substantially the same. The first light source device 10 and the second light source device 20 that are disposed to face each other and the light combining unit 34 are provided. When the light combining unit 34 is viewed along the direction orthogonal to the reference plane, the first light source device 10 side is provided. The first polarization separation / combination unit 40 having the first polarization separation / combination surface 48 arranged at an angle of about 45 ° with respect to the illumination optical axis 104ax and the second light source device 20 side, and illumination A second polarization separation / synthesis unit 54 having a second polarization separation / synthesis surface 59 disposed at an angle of about 45 ° with respect to the optical axis 104ax and substantially perpendicular to the first polarization separation / synthesis surface 48; The side opposite to the direction in which the part 34 emits light The illumination according to the first embodiment includes the reflection mirror 62 disposed and the λ / 4 plate 64 disposed between the reflection mirror 62 and the first polarization separation / combination unit 40 and the second polarization separation / synthesis unit 54. Similarly to the device 100, the light emitted from the first light source device 10 and the light emitted from the second light source device 20 are combined by the light combining unit 34, and the first light source device 10, which is a pair of light source devices, The light emitted from each of the second light source devices 20 is incident on substantially the same region in the first lens array 120, and is an illumination device that can be suitably used for a high-intensity projector. Even if the light emission of any one of the light source devices is weakened or cut off, it is possible to suppress the in-plane light intensity distribution in the illuminated area from being uneven and the quality of the projected image is poor. It becomes an illuminating device which can suppress becoming.

  Moreover, according to the illuminating device 104 which concerns on Embodiment 3, since it has further the (lambda) / 2 board 70 arrange | positioned between the 1st polarization separation / synthesis part 40 and the 2nd polarization separation / synthesis part 54, it is 1st polarization separation. The polarization separation / synthesis characteristics of the synthesis surface 40 and the second polarization separation / synthesis surface 54 can be made uniform, and as a result, the in-plane light intensity distribution in the illuminated region can be made more uniform.

  Further, according to the illumination device 104 according to the third embodiment, the first polarization separation / synthesis surface 48 and the second polarization separation / synthesis surface 59 pass light composed of p-polarized light and reflect light composed of s-polarized light. It is possible to increase the light use efficiency of the lighting device.

  The illumination device 104 according to the third embodiment has the same configuration as that of the illumination device 100 according to the first embodiment except that the light combining unit further includes a λ / 2 plate and the configuration of the second polarization separation / reflection surface. Therefore, it has the corresponding effect as it is among the effects of the lighting device 100 according to the first embodiment.

[Embodiment 4]
FIG. 8 is a top view illustrating the light combining unit 36 according to the fourth embodiment.
In FIG. 8, reference symbol L <b> 1 (p → s → p) is converted from p-polarized light to s-polarized light out of the light emitted from the first light source device 10, and further to p-polarized light. Reference numeral L2 (p → s → p) denotes converted light. Light emitted from the second light source device 20 is converted from p-polarized light to s-polarized light, and further p-polarized light. Shows the converted light.
8, the same members as those in FIGS. 2A, 6, and 7 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The illumination device 106 (not shown) according to the fourth embodiment has basically the same configuration as the illumination device 104 according to the third embodiment, but the orientation of the polarization separation / reflection surface is the illumination device according to the third embodiment. 104 is different. That is, the first polarization separation / synthesis surface 48 and the second polarization separation / synthesis surface 59 in the fourth embodiment are arranged in a so-called mountain shape as shown in FIG.

  The second polarization separation / combination unit 56 is disposed on the second light source device 20 side when viewed along the direction orthogonal to the reference plane, and has an angle of approximately 45 ° with respect to the illumination optical axis 106ax (not shown). And a second polarization separation / synthesis surface 59 arranged substantially perpendicular to the first polarization separation / synthesis surface 48. The second polarization separation / combination unit 56 is formed of a prism type PBS.

  Here, the trajectory of light in the light combining unit 34 will be mainly described with reference to FIG.

The light L1 emitted from the first light source device 10 is first separated into light composed of p-polarized light and light composed of s-polarized light by the first polarization separation / synthesis surface 48.
Of the light emitted from the first light source device 10, the light L 1 (p) composed of p-polarized light passes through the first polarization separation / synthesis surface 48, and the light L 1 composed of s-polarized light by the λ / 2 plate 70 (p → s ) And reflected by the second polarization separation / combination surface 59 toward the polarization conversion reflection unit 60, and then converted into p-polarized light L1 (p → s → p) by the polarization conversion reflection unit 60. Reflected towards the array 120.
Of the light emitted from the first light source device 10, the light L <b> 1 (s) composed of s-polarized light is reflected toward the first lens array 120 by the first polarization separation / synthesis surface 48.

The light L2 emitted from the second light source device 20 is first separated into light composed of p-polarized light and light composed of s-polarized light by the second polarization separation / combination surface 58.
Of the light emitted from the second light source device 20, the light L <b> 2 (p) composed of p-polarized light passes through the second polarization separation / combination surface 59, and the light L <b> 2 composed of s-polarized light by the λ / 2 plate 70 (p → s ) And reflected toward the polarization conversion reflection unit 60 by the first polarization separation / synthesis surface 48, and then the first lens as light L2 (p → s → p) composed of p-polarized light by the polarization conversion reflection unit 60. Reflected towards the array 120.
Of the light emitted from the second light source device 20, the light L <b> 2 (s) composed of s-polarized light is reflected toward the first lens array 120 by the second polarization separation / synthesis surface 59.

  At this time, the light L1 (p) composed of p-polarized light out of the light emitted from the first light source device 10 was converted into light L1 (p → s) composed of s-polarized light, and further converted into light composed of p-polarized light. The light L1 (p → s → p) and the light L2 (s) composed of s-polarized light out of the light emitted from the second light source device 20 are combined by the second polarization separation / synthesis surface 59. Further, light L1 (s) composed of s-polarized light out of the light emitted from the first light source device 10 and light L2 (p) composed of p-polarized light out of the light emitted from the second light source device 20 from s-polarized light. The light L2 (p → s → p) converted into light L2 (p → s) and further converted into light composed of p-polarized light is synthesized by the first polarization separation / synthesis surface 48.

In the first lens array 120 (not shown), the light L1 (p) composed of p-polarized light emitted from the first light source device 10 is converted into light L1 (p → s) composed of s-polarized light. Further, the light L1 (p → s → p) converted into light composed of p-polarized light and the light L2 (s) composed of s-polarized light emitted from the second light source device 20 are substantially in the same region. Is incident on.
The first lens array 120 includes light L1 (s) composed of s-polarized light out of the light emitted from the first light source device 10 and light composed of p-polarized light out of the light emitted from the second light source device 20. Light L2 (p → s → p) converted from light L2 (p → s) from L2 (p) into light L2 (p → s → p), and further converted into light made of p-polarized light is incident on substantially the same region.
That is, the light emitted from the first light source device 10 and the light emitted from the second light source device 20 are incident on substantially the same region in the first lens array 120.

  As described above, the illuminating device 106 according to the fourth embodiment is different from the illuminating device 104 according to the third embodiment in the direction of the polarization separating / reflecting surface, but the first light source device 10 and the second light source device 10 that are disposed substantially face to face. A light source device 20 and a light combining unit 36 are provided, and the light combining unit 36 is disposed on the first light source device 10 side when viewed along a direction orthogonal to the reference plane and is approximately 45 with respect to the illumination optical axis 106ax. The first polarization separation / combination unit 42 having the first polarization separation / synthesis surface 48 arranged at an angle of ° and the second light source device 20 side are arranged at an angle of about 45 ° with respect to the illumination optical axis 106ax. And a second polarization separation / combination unit 56 having a second polarization separation / combination surface 59 arranged substantially perpendicular to the first polarization separation / combination surface 48, and a direction opposite to the direction in which the light synthesis unit 36 emits light. Reflection mirror 62 and reflection mirror 6 2 and the λ / 4 plate 64 disposed between the first polarization separation / combination unit 42 and the second polarization separation / combination unit 56, the light synthesis unit 36, similarly to the illumination device 106 according to the third embodiment. The light emitted from the first light source device 10 and the light emitted from the second light source device 20 are combined and emitted from each of the first light source device 10 and the second light source device 20 which are a pair of light source devices. The illumination light is incident on substantially the same region in the first lens array 120 and can be suitably used for a high-brightness projector, and the light emission of any one of the pair of light source devices Illumination device capable of suppressing non-uniform in-plane light intensity distribution in the illuminated area and preventing the quality of the projected image from deteriorating even if the light is weakened or cut off It made.

  The illumination device 106 according to the fourth embodiment has the same configuration as that of the illumination device 104 according to the third embodiment except for the orientation of the polarization separation / reflection surface, and thus the effect of the illumination device 104 according to the third embodiment. Of the relevant effects.

[Embodiment 5]
FIG. 9 is a perspective view of the first light source devices 10 and 11, the second light source devices 20 and 21, and the light combining units 30 and 31 according to the fifth embodiment.
FIG. 10 shows how the light emitted from the first light source devices 10 and 11 and the light emitted from the second light source devices 20 and 21 in the illumination device 108 according to the fifth embodiment are the first lens array 128. It is a figure which shows whether it injects into.
9, the same members as those in FIGS. 1 and 2A are denoted by the same reference numerals, and detailed description thereof is omitted.

  A lighting device 108 (not shown) according to the fifth embodiment basically has a configuration in which two sets of the lighting devices 100 according to the first embodiment are arranged vertically. That is, as shown in FIG. 9, the illumination device 108 includes two sets of first light source devices 10 and 11, two sets of second light source devices 20 and 21, two sets of light combining units 30 and 31, and lens integrator optics. A system 118 (not shown).

  According to the illuminating device 108 according to the fifth embodiment, basically, since the illuminating device 100 according to the first embodiment has a configuration in which two sets of the illuminating devices 100 are arranged vertically, it is possible to obtain a higher-luminance lighting device. .

  In addition, since the illuminating device 108 according to the fifth embodiment basically has a configuration in which two sets of the illuminating devices 100 according to the first embodiment are arranged vertically, the effect of the illuminating device 100 according to the first embodiment is maintained as it is. Have.

[Embodiment 6]
FIG. 11 is a view for explaining the illumination device 109 according to the sixth embodiment. FIG. 11A is a top view showing an optical system of the illumination device 109, and FIG. 11B shows the light emitted from the first light source device 10 and the second light source device 20 in the illumination device 109. It is a figure which shows how light injects into the 1st lens array 129. FIG.
In FIG. 11, the same members as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The illumination device 109 according to the sixth embodiment basically has the same configuration as the illumination device 100 according to the first embodiment, but the arrangement angle of the light source device and the configuration of the lens integrator optical system according to the first embodiment are the same. 100 is different.

  In the illumination device 109, as shown in FIG. 11A, the angle between the optical axis 19ax of the first light source device 10 and the illumination optical axis 109ax is R1 when viewed along a direction orthogonal to the reference plane. Assuming that the angle between the optical axis 29ax of the second light source device 20 and the illumination optical axis 109ax is R2, the first light source device 10 and the second light source device 20 are “R1 = R2” and “R1 = 80”. “°”.

  The lens integrator optical system 119 includes a first lens array 129, a second lens array 139, a polarization conversion element 149, and a superimposing lens 159. Although detailed description is omitted, each optical element of the lens integrator optical system 119 has a smaller area than each optical element of the lens integrator optical system 110 in the first embodiment (shown in FIG. 11B described later). Except for the first lens array 129), it has the same configuration as each optical element of the lens integrator optical system 110.

  In the first lens array 129, as shown in FIG. 11B, the light L1 (p) emitted from the first light source device 10 as light composed of p-polarized light and the second light source device 20 composed of p-polarized light. From the light L2 (p → s) converted from the light L2 (p) emitted as light into light composed of s-polarized light and the light L1 (s) emitted as light composed of s-polarized light from the first light source device 10 The light L1 (s → p) converted into light composed of p-polarized light and the light L2 (s) emitted as light composed of s-polarized light from the second light source device 20 enter substantially the same region.

  As described above, the illuminating device 109 according to the sixth embodiment is different from the illuminating device 100 according to the first embodiment in the arrangement angle of the light source device and the configuration of the lens integrator optical system. The light source device 10, the second light source device 20, and the light combining unit 30 are arranged on the first light source device 10 side when viewed along the direction orthogonal to the reference plane and the illumination optical axis. The first polarization separation / combination unit 40 having the first polarization separation / combination surface 48 disposed at an angle of approximately 45 ° with respect to 109ax and the second light source device 20 side, and approximately 45 with respect to the illumination optical axis 109ax. A second polarization separation / combination unit 50 having a second polarization separation / combination surface 58 arranged at an angle of 0 ° and substantially perpendicular to the first polarization separation / combination surface 48; and a direction in which the light synthesis unit 30 emits light. Placed on the opposite side And the λ / 4 plate 64 disposed between the reflection mirror 62 and the first polarization separation / combination unit 40 and the second polarization separation / combination unit 50. Similarly to 100, the light emitted from the first light source device 10 and the light emitted from the second light source device 20 are synthesized by the light combining unit 30, and the first light source device 10 that is a pair of light source devices and the first light source device 10. The light emitted from each of the two light source devices 20 is incident on substantially the same region in the first lens array 129, and is an illuminating device that can be suitably used for a high-intensity projector. Even if the light emission of any of the light source devices is weakened or cut off, it is possible to suppress the in-plane light intensity distribution in the illuminated area from becoming uneven and the quality of the projected image is deteriorated. It becomes an illumination apparatus that can suppress.

  Further, according to the illumination device 109 according to the sixth embodiment, the first light source device 10 and the second light source device 20 are arranged so that “R1 = R2” and “R1 = 80 ° (R1 <90 °)”. As light emitted from the first light source device 10 as light composed of p-polarized light, light emitted from the first light source device 10 as light composed of s-polarized light, and light emitted from the second light source device 20 as light composed of p-polarized light. Since the emitted light and the light emitted as the s-polarized light from the second light source device are incident on substantially the same region in the first lens array 129, all of the light emitted from the pair of light source devices is present. In the first lens array 129, light is incident on substantially the same region (single region), so that the light use efficiency can be improved, and the in-plane light intensity distribution in the illuminated region can be made more uniform. It becomes possible. In addition, the area of the first lens array 129 can be reduced, and the entire illumination device can be reduced in size.

  The illumination device 109 according to the sixth embodiment has the same configuration as that of the illumination device 100 according to the first embodiment except for the arrangement angle of the light source device and the configuration of the lens integrator optical system. Among the effects of the lighting device 100, the corresponding effects are directly provided.

  As mentioned above, although this invention was demonstrated based on said embodiment, this invention is not limited to said embodiment. The present invention can be carried out in various modes without departing from the spirit thereof, and for example, the following modifications are possible.

(1) In the above embodiments, p-polarized light is used as one polarized light and s-polarized light is used as the other polarized light. However, the present invention is not limited to this. S-polarized light may be used as one polarized light and p-polarized light may be used as the other polarized light.

(2) In each of the above embodiments, prism-type PBSs are used as the first polarization separation / combination unit and the second polarization separation / combination unit, but the present invention is not limited to this. For example, a wire grid type polarizing plate may be used as the first polarization separation / synthesis unit and the second polarization separation / synthesis unit. In the illuminating device of the present invention, the first polarization separation / combination unit and the second polarization separation / combination unit made of the prism type PBS are also the first polarization separation / combination unit and the second polarization separation / combination unit made of a wire grid type polarizing plate. Both can be suitably used.

(3) In Embodiments 1 to 4 and Embodiment 6, the illumination device includes a pair of light source devices. In Embodiment 5, the illumination device 108 includes two pairs of light source devices. It is not limited to. Three or more pairs of light source devices may be provided.

(4) In the fifth embodiment, the illumination device 108 includes the light combining unit 30 corresponding to the first light source device 10 and the second light source device 20, and the light combining unit corresponding to the first light source device 11 and the second light source device 21. However, the present invention is not limited to this. The illumination device may include a single light combining unit corresponding to all of the two pairs of light source devices.

(5) In Embodiment 6 above, R1 is set to 80 °, but the present invention is not limited to this. R1 may be smaller than 90 °, in short, light emitted from the first light source device as light composed of one polarized light, light emitted from the first light source device as light composed of the other polarized light, and the second light source. The light emitted from the device as light having one polarization and the light emitted from the second light source device as light having the other polarization are incident on substantially the same region in the first lens array. It only has to be.

(6) In each of the above embodiments, the light source device having a parabolic reflector is used, but the present invention is not limited to this. For example, a light source device having an ellipsoidal reflector may be used. In this case, the light source device may emit the light focused on the focal point of the ellipsoidal reflector as it is, or may emit after collimating with a collimating lens or the like.

(7) In each of the above embodiments, the light source device having the arc tube and the parabolic reflector is used as the light source device, but the present invention is not limited to this. A so-called solid light source device (such as a light emitting diode) may be used as the light source device.

(8) In the first embodiment, the projector using three liquid crystal type light modulation devices as the light modulation device has been described as an example. However, the present invention is not limited to this. The present invention can also be applied to a projector using one, two, four or more liquid crystal type light modulation devices.

(9) Although the transmissive projector is used in the first embodiment, the present invention is not limited to this. For example, a reflective projector may be used. Here, “transmission type” means that a light modulation device as a light modulation means such as a transmission type liquid crystal display device transmits light, and “reflection type” This means that the light modulation device as the light modulation means, such as a reflective liquid crystal display device, is a type that reflects light. Even when the present invention is applied to a reflective projector, the same effect as that of a transmissive projector can be obtained.

(10) In the first embodiment, the liquid crystal light modulators 400R, 400G, and 400B are used as the light modulators of the projector 1000, but the present invention is not limited to this. In general, the light modulation device only needs to modulate incident light according to image information, and a micromirror light modulation device or the like may be used. For example, a DMD (digital micromirror device) (trademark of TI) can be used as the micromirror light modulator.

(11) The present invention can be applied to a rear projection type projector that projects from a side opposite to the side that observes the projected image, even when applied to a front projection type projector that projects from the side that observes the projected image. Is also possible.

(12) In each of the above embodiments, the example in which the illumination device of the present invention is applied to a projector has been described, but the present invention is not limited to this. For example, the lighting device of the present invention can be applied to other optical devices (for example, an optical disk device, a car headlamp, a lighting device, etc.).

DESCRIPTION OF SYMBOLS 10,11 ... 1st light source device, 10ax, 19ax ... Optical axis of 1st light source device, 12, 22 ... Arc tube, 14, 24 ... Parabolic reflector, 20, 21 ... 2nd light source device, 20ax, 29ax ... Optical axis of the second light source device, 30, 30a, 31, 32, 34, 36 ... light combining unit, 40, 42 ... first polarization separating / combining unit, 48 ... first polarization separating / combining surface, 48a ... first reflecting surface, 50, 52, 54, 56 ... second polarization separation / combination unit, 58, 59 ... second polarization separation / synthesis surface, 58a ... second reflection surface, 60 ... polarization conversion reflection unit, 62 ... reflection (of polarization conversion reflection unit) Mirror: 64 ... λ / 4 plate, 70 ... λ / 2 plate, 100, 109 ... illumination device, 100ax, 109ax ... illumination optical axis, 110 ... lens integrator optical system, 120,128,129 ... first lens array, 122 ... first lenslet, 130, 139: Second lens array, 132: Second small lens, 140, 149: Polarization conversion element, 150, 159: Superposition lens, 200: Color separation light guide optical system, 210, 220: Dichroic mirror, 230, 240, 250 Reflective mirror, 260, 270 ... Relay lens, 300R, 300G, 300B ... Condensing lens, 400R, 400G, 400B ... Liquid crystal type light modulator, 500 ... Cross dichroic prism, 600 ... Projection optical system, 1000 ... Projector, SCR …screen

Claims (7)

A first light source device and a second light source device;
A light combining unit that combines the light emitted from the first light source device and the light emitted from the second light source device, and emits the light toward a predetermined direction;
A lighting system comprising a lens integrator optical system that makes the in-plane light intensity distribution of the light from the light combining unit uniform;
The photosynthesis unit
A plane parallel to all of the optical axis of the first light source device, the optical axis of the second light source device, and the optical axis of the illumination device (hereinafter, the optical axis of the illumination device is referred to as an illumination optical axis). Is a reference plane, when viewed along a direction perpendicular to the reference plane,
A first polarization separation / synthesis unit disposed on the first light source device side and having a first polarization separation / synthesis surface disposed at an angle of approximately 45 ° with respect to the illumination optical axis;
A second polarization separation / synthesis surface disposed on the second light source device side, disposed at an angle of approximately 45 ° with respect to the illumination optical axis, and disposed substantially perpendicular to the first polarization separation / synthesis surface; A second polarization separation / synthesis unit;
A reflection mirror disposed on a side opposite to a direction in which the light combining unit emits light;
The reflection mirror, and a λ / 4 plate disposed between the first polarization separation / synthesis unit and the second polarization separation / synthesis unit,
In the illumination device, the light emitted from the first light source device and the light emitted from the second light source device enter substantially the same region in the first lens array of the lens integrator optical system ,
When viewed along a direction perpendicular to the reference plane,
When the angle between the optical axis of the first light source device and the illumination optical axis is R1, and the angle between the optical axis of the second light source device and the illumination optical axis is R2,
The first light source device and the second light source device are arranged so that “R1 = R2” and “R1 <90 °”,
Light emitted from the first light source device as light composed of one polarized light, light emitted from the first light source device as light composed of the other polarized light, and light composed of one polarized light from the second light source device. The light emitted from the second light source device and the light emitted as the other polarized light are incident on substantially the same region in the first lens array . The lighting device according to claim 1.
The first polarization separation / synthesis surface transmits light composed of one polarized light, reflects light composed of the other polarized light,
The second polarization separation / synthesis surface reflects light composed of one polarized light, and from the other polarized light.
Let the light pass through,
When the reflection mirror and the λ / 4 plate are a polarization conversion reflection unit,
The light composed of one of the lights emitted from the first light source device passes through the first polarization separation / combination surface, and then is reflected toward the first lens array by the second polarization separation / combination surface. ,
Of the light emitted from the first light source device, the light composed of the other polarized light is reflected toward the polarization conversion reflection unit by the first polarization separation / synthesis surface, and then reflected by the polarization conversion reflection unit. Reflected to the first lens array as polarized light,
The light composed of one polarization out of the light emitted from the second light source device is reflected toward the polarization conversion reflection unit by the second polarization separation / synthesis surface, and is then reflected by the polarization conversion reflection unit. Reflected to the first lens array as polarized light,
The light having the other polarization out of the light emitted from the second light source device passes through the second polarization separation / combination surface and then is reflected toward the first lens array by the first polarization separation / combination surface. ,
The light emitted from the first light source device as light having one polarized light and the light emitted from the second light source device as light having one polarized light are in substantially the same region in the first lens array. Incident,
The light emitted from the first light source device as light having the other polarization and the light emitted from the second light source device as light having the other polarization are in substantially the same region in the first lens array. An illumination device characterized by being incident. The lighting device according to claim 1.
The illumination device further includes a λ / 2 plate disposed between the first polarization separation / synthesis unit and the second polarization separation / synthesis unit,
The first polarization separation / synthesis surface transmits light composed of one polarized light, reflects light composed of the other polarized light,
The second polarization separation / synthesis surface transmits light composed of one polarized light, reflects light composed of the other polarized light,
When the reflection mirror and the λ / 4 plate are a polarization conversion reflection unit,
The light composed of one of the lights emitted from the first light source device passes through the first polarization separation / synthesis surface and is converted into light composed of the other polarization by the λ / 2 plate.
And reflected toward the first lens array by the second polarization separation / synthesis surface,
Of the light emitted from the first light source device, the light composed of the other polarized light is reflected toward the polarization conversion reflection unit by the first polarization separation / synthesis surface, and then reflected by the polarization conversion reflection unit. Reflected to the first lens array as polarized light,
The light composed of one polarized light out of the light emitted from the second light source device passes through the second polarization separation / combination surface and is converted into light composed of the other polarized light by the λ / 2 plate. Reflected toward the first lens array at the first polarization separation / synthesis surface;
The light having the other polarization out of the light emitted from the second light source device is reflected by the second polarization separation / synthesis surface toward the polarization conversion reflection unit, and then is reflected by the polarization conversion reflection unit. Reflected to the first lens array as polarized light,
Light emitted from the first light source device as light having one polarization and light emitted from the second light source device as light having the other polarization are in substantially the same region in the first lens array. Incident,
The light emitted from the first light source device as light having the other polarization and the light emitted from the second light source device as light having the one polarization are in substantially the same region in the first lens array. An illumination device characterized by being incident. In the illuminating device in any one of Claims 1-3 ,
The illumination apparatus according to claim 1, wherein the first polarization separation / combination unit and the second polarization separation / combination unit include a prism-type polarization beam splitter. In the illuminating device in any one of Claims 1-4 ,
The lighting device according to claim 1, wherein the first polarization separation / combination unit and the second polarization separation / combination unit include wire grid type polarizing plates. In the illuminating device in any one of Claims 1-5 ,
When the first light source device and the second light source device are a pair of light source devices,
The illumination device includes two or more pairs of light source devices. The lighting device according to any one of claims 1 to 6 ,
A light modulation device that modulates illumination light from the illumination device according to image information;
A projector comprising: a projection optical system that projects the modulated light from the light modulation device as a projection image.