JP2009175308A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector equipped with an illumination system capable of effectively taking in luminous flux from a light source into a first lens array. <P>SOLUTION: A light source device 10 has a difference of a light condensed state between in a direction X and in a direction Y. Thereby, the cross-sectional shape of the luminous flux emitted from the light source device 10 is adjusted to prevent the loss of light quantity in which the luminous flux going toward the first lens array 23 via a reflector 12 from a light emitting tube 11 is intercepted in such a state that it partially projects to the outside of the first lens array 23. Furthermore, since a plurality of element lenses 23a constituting the first lens array 23 have a difference of power between in the direction X and in the direction Y so as to cancel the difference of the light condensed state of the light source device 10, the luminous flux emitted from the first and the second lens arrays 23 and 24 enters a superposing lens 25 or the like in an appropriate convergent state or divergent state. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a projector that projects an image formed by a light modulation device such as a liquid crystal panel on a screen.

As a projector, for example, a reflector that reflects white light emitted from the light source unit;
A first lens array and a second lens array for uniformizing the light flux from the light source section and the reflector; a polarization conversion element for aligning the polarization direction of the light flux that has passed through both lens arrays; and a superimposing lens for superimposing the light flux that has passed through both lens arrays. There exists a thing provided with (refer patent document 1).
JP 2005-164838 A

However, in the projector as described above, the vertical and horizontal lengths of the first lens array are different. For example, when such a difference in length becomes large, the circular cross-section emitted from the light source unit via the reflector is different. White light tends to be partially shielded from the first lens array in a specific direction. Here, it is conceivable that the light beam cross section of the white light from the light source unit is made relatively small so as to be completely accommodated in the first lens array. In this case, however, the first lens array is in the direction perpendicular to the specific direction. There is a possibility that the uniformity of the illumination light is deteriorated without being effectively utilized.

SUMMARY An advantage of some aspects of the invention is to provide a projector including an illumination system that can take a light beam from a light source into a first lens array without waste.

In order to solve the above problems, a projector according to the present invention includes (a) a light source having a light emitting tube and a reflecting mirror that reflects the light beam from the light emitting tube forward, and (b) a light beam emitted from the light source. A first lens array that divides a plurality of partial light beams by a plurality of element lenses; and (c) a second lens array that individually adjusts the states of the plurality of divided light beams emitted from the first lens array by the plurality of element lenses. (D) a superimposing lens that superimposes a plurality of split light fluxes that have passed through the second lens array on a target illuminated area, and (a1) the light source has a first direction perpendicular to the system optical axis. And a system light axis and a second direction perpendicular to the first direction to adjust the cross-section of the light beam emitted from the light source by (c1) the first
The plurality of element lenses constituting at least one of the lens array and the second lens array have a power difference between the first direction and the second direction so as to tend to cancel the difference in the light collection state of the light source. .

According to the projector, since the light source adjusts the cross-sectional shape of the light beam emitted from the light source by having a difference in the condensed state between the first direction and the second direction, the first light source passes through the reflecting mirror from the arc tube. It is possible to prevent a light beam traveling toward the lens array from partially protruding outside the first lens array in a specific direction and being blocked and causing a light amount loss. Here, since the plurality of element lenses constituting at least one of the lens arrays have a difference in power between the first direction and the second direction so as to tend to cancel the difference in the light collection state of the light source. The light beam emitted from the second lens array is incident on the next optical component including the superimposing lens in an appropriate convergent state or divergent state. Thereby, the illumination light that has passed through the superimposing lens is in a state of illuminating the illuminated area relatively uniformly and efficiently.

According to a specific aspect or aspect of the present invention, in the projector, the first lens array has a rectangular outline in which the length in the first direction is different from the length in the second direction. In this case, according to the rectangular outline of the first lens array, the first lens array can be illuminated without waste in the first direction and the second direction.

According to another aspect of the present invention, the plurality of element lenses constituting at least one of the first lens array and the second lens array have a toric type optical surface. In this case, one surface of the element lens constituting any lens array has a special shape.

According to still another aspect of the present invention, the plurality of element lenses constituting at least one of the first lens array and the second lens array have a cylindrical optical surface and a spherical optical surface. In this case, the element lenses constituting both lens arrays can have a general surface shape such as a cylindrical type or a spherical type.

According to still another aspect of the present invention, the light source includes an elliptical mirror that is a reflecting mirror, and a collimating lens such as a concave lens that makes the light beam from the elliptical mirror substantially parallel. In this case, the light source light collected by the elliptical mirror can be extracted as a parallel light flux through the collimating lens.

According to still another aspect of the present invention, the collimating lens has a toric type optical surface.
In this case, one surface of the collimating lens has a special shape.

According to still another aspect of the present invention, the collimating lens has a cylindrical optical surface and a spherical optical surface. In this case, the collimating lens can have a general surface shape such as a cylindrical type or a spherical type.

According to still another aspect of the invention, the reflecting mirror has a toric reflecting surface. In this case, the reflecting surface of the reflecting mirror has a special shape.

According to yet another aspect of the present invention, in order to align the polarization direction of the light beam from the light source, a plurality of prism elements each having a polarization separation film, a reflection film, and a phase difference plate are arranged in a lateral direction orthogonal to the longitudinal direction. And the longitudinal direction of the plurality of prism elements corresponds to the first direction, and the width of the first lens array in the first direction is larger than the width of the first lens array in the second direction. long. In this case, since the length in the first direction of the first lens array is longer than the length in the second direction, the element lenses constituting the first lens array can be formed without increasing the number of prism elements constituting the polarization converter. You can increase the number. Therefore, relatively uniform illumination light can be obtained without making the illumination system expensive and complicated.

According to still another aspect of the present invention, (e) a color separation light guide optical system that separates a light beam emitted from the superimposing lens into light beams of each color, and (f) each color emitted from the color separation light guide optical system. A light modulation device for each color that modulates each light beam according to image information, (g) a light combining optical system that combines the modulated light beams of each color emitted from each color light modulation device, and (h) a light combining optical system. A projection optical system for projecting the combined image light. In this case, a bright color image with little unevenness can be projected.

[First Embodiment]
FIG. 1 is a plan view conceptually illustrating the structure of the optical system of the projector according to the first embodiment of the invention. The projector 100 is an optical device for modulating a light beam emitted from a light source in accordance with image information to form an optical image, and enlarging and projecting the optical image on a screen. An optical system 20, a color separation light guide optical system 30, a light modulation unit 40,
A cross dichroic prism 50 and a projection lens 60 are provided. Here, the light modulator 4
0 includes three liquid crystal light valves 40a, 40b and 40c having a similar structure.

In the projector 100, the light source device 10 includes, as illumination light sources, a discharge light-emitting arc tube 11, a reflector 12 that is an elliptical reflecting mirror, a sub-mirror 13 that is a spherical sub-reflecting mirror, and a collimator. And a collimating lens 14. The light beam radiated from the arc tube 11 to the surroundings is reflected by the reflector 12 of the elliptical mirror, or reflected by the sub-mirror 13 and further reflected by the reflector 12 to be a converged light beam, and then collimated by the collimating lens 14. A light beam is incident on the front side, that is, the first lens array 23 of the homogenizing optical system 20. The collimating lens 14 is a toric lens whose refractive power, that is, power is different between the X direction and the Y direction perpendicular to the system optical axis OA, which will be described in detail later.

The homogenizing optical system 20 is for supplying illumination light with uniform illuminance to the light modulation unit 40 and the like, and first and second that divide the light beam emitted from the light source device 10 into an appropriate state. Lens arrays 23 and 24, a superimposing lens 25 that superimposes a plurality of light beams that have passed through both lens arrays 23 and 24, and a polarization conversion element 27 that aligns the polarization directions of the light beams incident on the superimposing lens 25 are provided. In the homogenizing optical system 20, the first and second lens arrays 23 and 24 each include a plurality of element lenses 23a and 24a arranged in a matrix. Among these, the element lens 23a constituting the first lens array 23 divides the light beam that has passed through the collimating lens 14, and the element lens 24a constituting the second lens array 24 appropriately divides the divided light beam from the first lens array 23. Ejection with a divergence angle. In addition, the 1st arrange | positioned at the light source device 10 side.
As will be described in detail later, each element lens 23a of the lens array 23 is a toric lens having different powers in the X direction and the Y direction perpendicular to the system optical axis OA. The superimposing lens 25 is
The illumination light emitted from the second lens array 24 and having passed through the polarization conversion element 27 is appropriately converged as a whole, and is superimposed on the illuminated area, that is, the display area, of the liquid crystal light valves 40a, 40b, and 40c provided in the subsequent light modulation section 40. Enable lighting. The polarization conversion element 27 is a polarization conversion unit formed of a PBS array, and has a role of aligning the polarization direction of each partial light beam divided by the first lens array 23 and passing through the second lens array 24 to one direction of linearly polarized light. . The polarization conversion element 27 is a prism array having a structure in which four prism elements 27a each having the same structure and extending in the Y direction are arranged in the X direction. Each prism element 27a is fixed to the exit surface of the prism that is perpendicular to the system optical axis OA and the polarization separation film and the reflective film that are arranged in an inclined state with respect to the system optical axis OA using the slope of the prism. And a phase difference plate. The longitudinal direction in which each prism element 27a extends is the Y direction corresponding to the first direction, and the lateral direction of each prism element 27a is the X direction corresponding to the second direction.

The color separation light guide optical system 30 includes first and second dichroic mirrors 31a and 31b, reflection mirrors 32a, 32b, and 32c, and three field lenses 33a, 33b, and 33c, and is emitted from the uniformizing optical system 20. The illuminating light is separated into three colors of red (R), green (G), and blue (B), and each color light is guided to the liquid crystal light valves 40a, 40b, and 40c at the subsequent stage.
More specifically, first, the first dichroic mirror 31a reflects R light and transmits G light and B light among the three colors of RGB. The second dichroic mirror 31b
Of the two colors B, G light is reflected and B light is transmitted. In the color separation light guide optical system 30, the R light reflected by the first dichroic mirror 31a enters the field lens 33a for adjusting the incident angle through the reflection mirror 32a. The first dichroic mirror 3
The G light transmitted through 1a and reflected by the second dichroic mirror 31b is incident on a field lens 33b for adjusting the incident angle. Furthermore, the second dichroic mirror 31b
The B light that has passed through passes through the relay lenses LL1 and LL2 and the reflection mirrors 32b and 32c and enters the field lens 33c for adjusting the incident angle.

Each of the liquid crystal light valves 40a, 40b, and 40c constituting the light modulation unit 40 is a non-light-emitting light modulation device that modulates the spatial intensity distribution of incident illumination light. Liquid crystal light valve 40a,
Reference numerals 40b and 40c denote three image display liquid crystal panels 41a, 41b, and 41c that are illuminated corresponding to the respective color lights emitted from the color separation light guide optical system 30, and the respective image display liquid crystal panels 41a, 41b, and 40c. Three first polarizing filters 42a disposed on the incident side of 41c,
42b, 42c, and three second polarizing filters 43a, 43b, 43c disposed on the exit side of the image display liquid crystal panels 41a, 41b, 41c, respectively.

In the light modulator 40, the R light reflected by the first dichroic mirror 31a enters the liquid crystal light valve 40a via the field lens 33a and the like, and the liquid crystal light valve 4
The display area on the image display liquid crystal panel 41a constituting 0a is illuminated. The G light transmitted through the first dichroic mirror 31a and reflected by the second dichroic mirror 31b enters the liquid crystal light valve 40b via the field lens 33b and the like, and the liquid crystal light valve 40b.
Illuminates the display area on the image display liquid crystal panel 41b. The B light transmitted through both the first and second dichroic mirrors 31a and 31b enters the liquid crystal light valve 40c through the field lens 33c and the like, and is displayed on the image display liquid crystal panel 41c constituting the liquid crystal light valve 40c. Illuminate the area. Each of the image display liquid crystal panels 41a to 41c modulates the spatial distribution of the polarization direction of the incident illumination light. Each image display liquid crystal panel 41a-41c
The polarization states of the three colors of light that are incident on the liquid crystal panels 41a to 41c are adjusted in units of pixels in accordance with drive signals or image signals input as electrical signals to the image display liquid crystal panels 41a to 41c. At this time, the first polarizing filters 42a to 42c are used to display the image display liquid crystal panels 41a to 41c.
The polarization direction of the illumination light incident on c is adjusted, and the second polarizing filters 43a to 43c are adjusted.
Thus, modulated light having a predetermined polarization direction is extracted from the modulated light emitted from the image display liquid crystal panels 41a to 41c. As described above, the respective liquid crystal light valves 40a, 40b, 40c.
Forms image light of each color corresponding to each.

The cross dichroic prism 50 is a liquid crystal light valve 40 as a light combining optical system.
The image light of each color from a, 40b, and 40c is synthesized. More specifically, the cross dichroic prism 50 has a substantially square shape in plan view in which four right angle prisms are bonded together.
A pair of dielectric multilayer films 51a intersecting in an X shape is formed at the interface where the right-angle prisms are bonded together.
, 51b are formed. One first dielectric multilayer film 51a reflects R light, and the other second dielectric multilayer film 51b reflects B light. The cross dichroic prism 50 reflects the R light from the liquid crystal light valve 40a by the dielectric multilayer film 51a and emits the G light from the liquid crystal light valve 40b through the dielectric multilayer films 51a and 51b. The B light from the liquid crystal light valve 40c is reflected by the dielectric multilayer film 51b and emitted to the left in the traveling direction. In this way, the R light, the G light, and the B light are combined by the cross dichroic prism 50 to form combined light that is image light based on a color image.

The projection lens 60 is a projection optical system, and projects the color image on a screen (not shown) by enlarging the image light by the combined light formed through the cross dichroic prism 50 with a desired magnification.

2A is a diagram for explaining the state of the light beam in the XZ plane in the light source device 10 and the uniformizing optical system 20, and FIG. 2B is a diagram for explaining the state of the light beam in the YZ plane. It is a figure to do.

The light flux L11 on the center side and the light flux L12 or the light flux L22 on the outer side are condensed by the collimating lens 14 to be close to a parallel light flux (here, the condensed state is not limited to convergence but is parallel or divergent). Included). Here, the incident surface 14c of the collimating lens 14 is a spherical surface, and the curvature in the XZ plane is equal to the curvature in the YZ plane. On the other hand, the exit surface 14d of the collimating lens 14 is a toric surface having a stronger power in the X direction than in the Y direction.
The curvature in the XZ plane is larger than the curvature in the YZ plane. As a result, as shown in FIG. 3, the light beam L1 incident on the first lens array 23 from the collimating lens 14 has a light beam cross-sectional width in the X direction smaller than that in the Y direction. The first lens array 23
(See FIG. 4A for a specific illuminance distribution). The light beam L0 shown for reference corresponds to the case where the entrance surface 14c and the exit surface 14d of the collimating lens 14 are symmetrical spherical surfaces around the optical axis, and the contour of the first lens array 23 is shown. It protrudes out of 23z and causes a light amount loss (see FIG. 4B for a specific illuminance distribution). Here, the first lens array 23 is composed of a total of 32 element lenses 23a in 8 rows and 4 columns, and the aspect ratio of each element lens 23a, that is, the ratio of the width in the Y direction to the width in the X direction is 9: The aspect ratio of the contour 23z of the first lens array 23, that is, the ratio of the width in the Y direction to the width in the X direction is 18:16. As a result, the outline 23z of the first lens array 23 has a vertically long shape that is relatively long in the Y direction.

Returning to FIG. 2, the center-side light beam L <b> 11 incident on the first lens array 23, the outer light beam L <b> 12 with respect to the X direction, and the outer light beam L <b> 22 with respect to the Y direction are element lenses constituting the first lens array 23. After being separated from other partial beams by 23a, the second lens array 2
The light is collected near the position 4. Here, although the entrance surface 23c of the element lens 23a is a plane, its exit surface 23d is a toric surface having a stronger power in the Y direction than in the X direction.
The curvature in the XZ plane is smaller than the curvature in the YZ plane. As a result, the light beams L11, L12, and L22 incident on the second lens array 24 from the first lens array 23 ideally converge to approximately one point. That is, the convergence effect of the light beams L11, L12, and L22 by the collimating lens 14 having relatively strong power in the X direction is the same as the convergence effect of the light beams L11, L12, and L22 by the element lens 23a having relatively strong power in the Y direction. It is offset by the effect.

A central light beam L11 incident on the second lens array 24 and an outer light beam L in the X direction.
12 and the outer light beam L22 with respect to the Y direction are condensed with an appropriate divergence angle by the element lens 24a constituting the second lens array 24 (here, the condensed state is not limited to being converged but parallel or Including the case of divergence). In addition, the incident surface 24c of the element lens 24a is a flat surface, the exit surface 24d is a spherical surface, and both the surfaces 24c and 24d are
The power in the X direction is equal to the power in the Y direction. As a result, the second lens array 2
4, the light beam cross-sectional width in the X direction is equal to the light beam cross-sectional width in the Y direction.

In the polarization conversion element 27, the polarization separation film 27e transmits one of the P-polarized light and S-polarized light (for example, P-polarized light) included in each of the light beams L11, L12, and L22, and the other polarized light (for example, S-polarized light). To reflect. The reflected other polarized light is bent by the reflecting film 27f and emitted in the direction of emission of the one polarized light, that is, the direction along the system optical axis OA. Any of the emitted polarized light (for example, S-polarized light) is subjected to polarization conversion by the phase difference plate 27g provided on the light exit surface, and all the polarized light is aligned with, for example, P-polarized light.

For the collimating lens 14 described above, the entrance surface 14c can be a toric surface and the exit surface 14d can be a spherical surface. For the element lenses 23a constituting the first lens array 23, for example, the entrance surface 23c can be a toric surface and the exit surface 23d can be a plane.

As is apparent from the above description, according to the projector 100 of the present embodiment, the light source device 10 has a difference in light collection state between the X direction and the Y direction. As a result, the cross-sectional shape of the light beam L1 emitted from the light source device 10 can be adjusted, and the light beam L1 traveling from the arc tube 11 to the first lens array 23 via the reflector 12 is partially outside the first lens array 23 in the X direction. It is possible to prevent the light from being protruded and blocked to cause light loss. Further, since the plurality of element lenses 23a constituting the first lens array 23 have a power difference between the X direction and the Y direction so as to tend to cancel the difference in the condensing state of the light source device 10, the first lens array 23 has a difference in power. The light beams L11, L12, and L22 emitted from the second lens arrays 23 and 24 are incident on the superimposing lens 25 and the like in an appropriate convergent state or divergent state. Thereby, the illumination light that has passed through the superimposing lens 25 illuminates the illuminated areas of the liquid crystal light valves 40a, 40b, and 40c relatively uniformly and efficiently.

[Second Embodiment]
Hereinafter, the projector according to the second embodiment will be described with reference to FIG. The projector according to the second embodiment is a modification of the projector 100 according to the first embodiment, and parts that are not particularly described are the same as those of the projector 100 according to the first embodiment.

In this case, the incident surface 114c of the collimating lens 14 is a cylindrical optical surface,
The curvature in the XZ plane is an appropriate value, and the curvature in the YZ plane is zero. On the other hand, the exit surface 114d of the collimating lens 14 is a spherical surface, and the curvature in the XZ plane is equal to the curvature in the YZ plane. In the case of this embodiment, the entrance surface 114c and the exit surface 114d cooperate to function like a toric lens. As a result, as in the case of the first embodiment, as shown in FIG. 3, the light beam L1 incident on the first lens array 23 from the collimating lens 14 has a light beam cross-sectional width in the X direction and a light beam in the Y direction. The first lens array 23 is smaller than the cross-sectional width.
Is substantially within the outline 23z.

As a modification of the collimating lens 14 described above, the entrance surface 14c is a spherical surface, and the exit surface 14 is formed.
d may be a cylindrical surface.

[Third Embodiment]
Hereinafter, the projector according to the third embodiment will be described with reference to FIG. The projector according to the third embodiment is a modification of the projector 100 according to the first embodiment, and parts that are not particularly described are the same as those of the projector 100 according to the first embodiment.

In this case, in each of the element lenses 223a constituting the first lens array 23, the incident surface 2
23c is a cylindrical optical surface, and the curvature in the XZ plane is an appropriate value,
The curvature in the YZ plane is zero. On the other hand, the exit surface 223d of each element lens 223a is
It is a spherical surface, and the curvature in the XZ plane is equal to the curvature in the YZ plane. In the case of this embodiment, the incident surface 223c and the exit surface 223d cooperate to function like a toric lens. As a result, as in the case of the first embodiment, the converging effect of the light beam L11 by the collimating lens 14 having relatively strong power in the X direction is the element lens 2 having relatively strong power in the Y direction.
This is offset by the convergence effect of the light beam L11 by 23a.

As a modification of each element lens 223a constituting the first lens array 23 described above,
The entrance surface 223c may be a spherical surface, and the exit surface 223d may be a cylindrical surface.

[Fourth Embodiment]
Hereinafter, the projector according to the fourth embodiment will be described with reference to FIG. The projector according to the fourth embodiment is a modification of the projector 100 according to the first embodiment, and parts that are not particularly described are the same as those of the projector 100 according to the first embodiment.

In this case, in each element lens 324a constituting the second lens array 24, the incident surface 3
Although 24c is a plane, its exit surface 324d is a toric surface having a stronger power in the Y direction than in the X direction, and the curvature in the XZ plane is smaller than the curvature in the YZ plane. As a result, the light beam L11 emitted from the second lens array 24 ideally converges to approximately one point. That is, the collimating lens 1 having a relatively strong power in the X direction.
4 is offset by the bias of the convergence effect of the element lens 324a having relatively strong power in the Y direction.

In the above description, the incident surface 324c is a plane and the exit surface 324d is a toric surface. However, for example, the entrance surface 324c may be a cylindrical surface and the exit surface 324d may be a spherical surface.

Alternatively, the entrance surface 324c can be a toric surface and the exit surface 324d can be a plane.
The incident surface 324c may be a spherical surface, and the exit surface 324d may be a cylindrical surface.

[Fifth Embodiment]
The projector according to the fifth embodiment will be described below with reference to FIG. The projector according to the fifth embodiment is a modification of the projector 100 according to the first embodiment, and parts that are not particularly described are the same as those of the projector 100 according to the first embodiment.

In the case of the projector 400, in the light source device 10, the reflector 412 is a parabolic reflector, and the collimating lens 14 is omitted. Here, the reflecting surface of the reflector 412 is not a precise paraboloid but a toric surface having a stronger power in the X direction than in the Y direction, and the curvature in the XZ plane is larger than the curvature in the YZ plane. ing. As a result, as in the case of the first embodiment, as shown in FIG. 3, the light beam L1 incident on the first lens array 23 from the reflector 412 has a light beam cross-sectional width in the X direction and a light beam cross-sectional width in the Y direction. And is substantially within the outline 23z of the first lens array 23.

The present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

For example, various lamps such as a high-pressure mercury lamp and a metal halide lamp are conceivable as the lamp used in the light source device 10 of the above embodiment. Further, the light source device 10 can be a type of light source that does not have the secondary mirror 13.

In the above embodiment, an example in which the present invention is applied to a transmissive projector has been described. However, the present invention can also be applied to a reflective projector. here,"
"Transmission type" means that a liquid crystal light valve including a liquid crystal panel for image display is a type that transmits light, and "reflection type" is a type that a liquid crystal light valve reflects light. It means that. The light modulation device is not limited to a liquid crystal panel or the like, and may be a light modulation device using a micromirror, for example.

In addition, as the projector, there are a front projector that projects an image from the direction of observing the projection surface and a rear projector that projects an image from the side opposite to the direction of observing the projection surface. The configuration can be applied to both.

In the above embodiment, only the example of the projector 100 using the three image display liquid crystal panels 41a to 41c has been described. However, the present invention uses a projector using only one liquid crystal panel and two liquid crystal panels. The present invention can also be applied to a projector using four or more liquid crystal panels.

It is a top view explaining the projector of 1st Embodiment of this invention. (A) is a figure explaining the state of the light beam in XZ plane, (B) is a figure explaining the state of the light beam in YZ plane. It is a figure explaining the cross-sectional shape of the light beam which injects into a 1st lens array from a parallelizing lens. (A) is a figure explaining the specific shape of the light beam which injects into a 1st lens array from a parallelizing lens, (B) is a figure explaining the shape of the light beam of a comparative example. It is a figure explaining the projector of 2nd Embodiment. It is a figure explaining the projector of 3rd Embodiment. It is a figure explaining the projector of 4th Embodiment. It is a figure explaining the projector of 5th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Light source device, 11 ... Light-emitting tube, 12 ... Reflector, 13 ... Secondary mirror, 14 ... Parallelizing lens, 20 ... Uniformation optical system, 23 ... 1st lens array, 23a ... Element lens,
23z ... contour, 24 ... second lens array, 24a ... element lens, 25 ... superimposed lens, 27 ... polarization conversion element, 27a ... prism element, 30 ... color separation light guide optical system, 3
1a, 31b ... Dichroic mirror, 40 ... Light modulator, 40a, 40b, 40c ...
Liquid crystal light valve, 41a, 41b, 41c ... Liquid crystal panel, 42a, 42b, 42c
... 1st polarizing filter, 43a, 43b, 43c ... 2nd polarizing filter, 50 ... Cross dichroic prism, 60 ... Projection lens, 100 ... Projector, OA ... System optical axis

Claims (10)

A light source having an arc tube and a reflecting mirror that reflects the light flux from the arc tube forward;
A first lens array for dividing a light beam emitted from the light source into a plurality of partial light beams by a plurality of element lenses;
A second lens array that individually adjusts the states of the plurality of split light beams emitted from the first lens array by a plurality of element lenses;
A superimposing lens that superimposes and enters the plurality of divided light fluxes that have passed through the second lens array on a target illumination area, respectively,
The light source has a condensing state difference between a first direction perpendicular to the system optical axis and a second direction perpendicular to the system optical axis and the first direction, so that the light flux emitted from the light source Adjust the cross section,
The plurality of element lenses constituting at least one of the first lens array and the second lens array tend to cancel out the difference in the light collection state of the light source and the first direction and the first lens array. Having a power difference with respect to the two directions,
projector. The projector according to claim 1, wherein the first lens array has a rectangular outline in which a length in the first direction is different from a length in the second direction. The projector according to claim 1, wherein the plurality of element lenses constituting at least one of the first lens array and the second lens array have a toric type optical surface. The plurality of element lenses constituting at least one of the first lens array and the second lens array have a cylindrical optical surface and a spherical optical surface.
And the projector according to claim 2. The projector according to any one of claims 1 and 2, wherein the light source includes an elliptical mirror that is the reflecting mirror and a parallelizing lens that makes a light beam from the elliptical mirror substantially parallel. The projector according to claim 5, wherein the collimating lens has a toric type optical surface. The projector according to claim 5, wherein the collimating lens has a cylindrical optical surface and a spherical optical surface. The projector according to claim 1, wherein the reflecting mirror has a toric type reflecting surface. In order to align the polarization direction of the light beam from the light source, further comprising a polarization conversion unit in which a plurality of prism elements each having a polarization separation film, a reflection film, and a phase difference plate are arranged in a transverse direction perpendicular to the longitudinal direction,
The longitudinal direction of the plurality of prism elements corresponds to the first direction,
The width of the first lens array in the first direction is the second width of the first lens array.
The projector according to any one of claims 1 to 8, wherein the projector is longer than a width with respect to a direction. A color separation light guide optical system that separates the light beam emitted from the superimposing lens into a light beam of each color;
A light modulation device for each color that modulates a light beam of each color emitted from the color separation light guide optical system according to image information;
A light combining optical system that combines the modulated light beams of the respective colors emitted from the light modulation devices of the respective colors;
A projection optical system for projecting image light synthesized through the light synthesis optical system,
The projector according to any one of claims 1 to 9.

Images