JP2008209441A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector reducing white unevenness in a projected image. <P>SOLUTION: The projector 1000 includes: an illuminating device 100; a color separation optical system 200 that separates the light emitted from the illuminating device 100 into a plurality of color light rays and guides the rays to an area to be illuminated; a relay optical system 300 having a relay lens 330 to guide one color light ray among three color light rays separated by the color separation optical system 200; three liquid crystal devices 400R, 400G and 400B that modulate the three color light rays in accordance with corresponding image information; a cross dichroic prism 500 that synthesizes the modulated color light rays; a projection optical system 600 that projects the synthesized image light; and an optical axis correction optical system 700 disposed on the optical path between the light source device 110 and the cross dichroic prism 500. The optical axis correction optical system 700 is configured to emit the light so that the optical axis of the emitted light is inclined in a prescribed direction with respect to the optical axis of the incident light. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projector.

Conventionally, a color separation optical system that separates light from a lighting device into, for example, three color lights of red light, green light, and blue light and guides the light to an illuminated area, and three color lights separated by the color separation optical system A relay optical system having a relay lens for guiding one color light (e.g., blue light) to the illuminated area;
A projector is known that includes three electro-optic modulators that modulate three color lights guided by a color separation optical system and a relay optical system in accordance with image information, respectively (for example, see Patent Document 1).

  According to the conventional projector, since the relay optical system is provided, it is possible to make the light irradiated to the image forming area of each electro-optic modulator almost equal.

JP 2002-214565 A

  However, in the conventional projector, since the color light beams passing through the relay optical system are crossed by the relay lens, the color light passing through the relay optical system and the other two color lights not passing through the relay optical system In this case, the pattern of the in-plane luminance distribution is irradiated to the image forming area of the electro-optic modulation device in a form that is inverted vertically and horizontally. At this time, the in-plane light intensity distribution of the light from the illumination device may not be completely uniform, and in such a case, when combining the modulated light from each electro-optic modulation device, Due to the fact that the modulated light having the inverted in-plane luminance distribution is included, color unevenness occurs in the image light projected on the screen. In particular, when a white image is projected and displayed, there is a problem that a portion (so-called white unevenness) where a beautiful white color cannot be displayed occurs.

  Accordingly, the present invention has been made to solve such a problem, and an object thereof is to provide a projector capable of reducing white unevenness of a projected image.

  In order to solve the above problems, the present inventor has conducted extensive research on the cause of the in-plane light intensity distribution of light from the illumination device not being completely uniform. We have found that the tilt of the optical axis of the device is considered as one of the causes.

  That is, in the conventional projector, the optical axis of the light source device or the optical axis of the illumination device may be inclined with respect to the designed system optical axis due to distortion of the light guide or the like. For this reason, the in-plane light intensity distribution of the light from the illumination device does not become completely uniform, and as a result, color unevenness, particularly white unevenness, occurs in the image light projected on the screen.

  Based on the above knowledge, the present inventor seems to incline the optical axis of the light emitted relative to the optical axis of the incident light into the optical path from the light source device to the color synthesizing optical system. If the optical axis correction optical system configured as described above is arranged, the light from the illumination device can be transmitted even when the optical axis of the light source device or the optical axis of the illumination device is inclined with respect to the designed system optical axis. The in-plane light intensity distribution can be suppressed from becoming non-uniform, and as a result, it has been conceived that white unevenness can be reduced, and the present invention has been completed.

  The projector according to the present invention includes an illuminating device having a light source device that emits an illuminating light beam, a color separation optical system that separates light from the illuminating device into a plurality of color lights, and guides the light to an illuminated area, and the color separation optics. A relay optical system having a relay lens for guiding one color light of the plurality of color lights separated by the system to an illuminated area, and a plurality of color lights guided by the color separation optical system and the relay optical system. A plurality of electro-optic modulators that respectively modulate in accordance with image information, a color synthesis optical system that synthesizes each color light modulated by the plurality of electro-optic modulation devices, and image light synthesized by the color synthesis optical system A projection optical system for projecting; and an optical axis correction optical system disposed in an optical path from the light source device to the color synthesis optical system, and the optical axis correction optical system is incident on the optical axis correction optical system Against the optical axis of light Characterized in that it is configured to emit by tilting the optical axis of light emitted from Kihikarijiku correction optical system in a predetermined direction.

  For this reason, according to the projector of the present invention, the optical axis correction optical system having the above-described configuration is arranged in the optical path from the light source device to the color synthesis optical system. Even when the optical axis of the light source device or the optical axis of the illumination device is tilted, the optical axis of the illumination light beam emitted from the optical axis correction optical system can be aligned with the system optical axis. It is possible to prevent the in-plane light intensity distribution of light from becoming non-uniform. Thus, even if the in-plane luminance distribution pattern of one color light is inverted vertically and horizontally by the relay optical system, it may be almost the same as the in-plane luminance distribution pattern of the light before passing through the relay optical system. It becomes possible. That is, for the light irradiated to the image forming area of each electro-optic modulator, the in-plane luminance distribution pattern in which the color light that has passed through the relay optical system and the color light that has not passed through the relay optical system are substantially equal Become. As a result, it is possible to reduce the color unevenness of the image light projected on the screen, particularly the white color unevenness.

  In the projector according to the aspect of the invention, it is preferable that the optical axis correction optical system includes a plate-like member in which both the light incident surface and the light emitting surface are flat and the both surfaces are not parallel to each other.

  With this configuration, the optical axis of the emitted light can be inclined in a predetermined direction with respect to the optical axis of the incident light.

  In the projector according to the aspect of the invention, it is preferable that a dichroic filter for color correction is disposed on the plate-like member.

By the way, in recent years, the opportunity to use a projector for movie appreciation at home has increased, and a dichroic filter for color correction called a cinema filter is displayed so that a screen having a color tone suitable for movie appreciation or the like is displayed. An increasing number of projectors are equipped with (a filter for widening the color gamut and reducing the black float level). In a projector including such a dichroic filter for color correction, the brightness of the projected image is reduced by using the dichroic filter, and thus the above-described uneven whiteness of the projected image is more conspicuous.
On the other hand, according to the projector of the present invention, the dichroic filter for color correction is arranged on the plate-like member as the optical axis correction optical system. It becomes possible to reduce white unevenness.

  In the projector according to the aspect of the invention, the optical axis correction optical system includes a light incident surface and a light exit surface, one of which is a lens surface having a curvature and the other surface is a flat surface, and the optical axis of the lens surface is It is preferable to incline with respect to the normal of the plane.

  Also with this configuration, the optical axis of the emitted light can be tilted in a predetermined direction with respect to the optical axis of the incident light.

  In the projector according to the aspect of the invention, the optical axis correction optical system is a lens surface in which both of the light incident surface and the light exit surface have a curvature, and the optical axis of the lens surface of the light entrance surface is a lens of the light exit surface. It is preferable to be inclined with respect to the optical axis of the surface.

  Also with this configuration, the optical axis of the emitted light can be tilted in a predetermined direction with respect to the optical axis of the incident light.

  In the projector according to the aspect of the invention, it is preferable that the optical axis correction optical system is disposed in an optical path preceding the color separation optical system.

  With this configuration, the in-plane luminance distribution in all the optical paths can be made uniform all at once by one optical axis correction optical system disposed in front of the color separation optical system.

  In the projector according to the aspect of the invention, it is preferable that the projector further includes an attitude adjustment device capable of adjusting the attitude of the optical axis correction optical system.

  By configuring in this way, it is possible to finely adjust the posture (arrangement angle, etc.) of the optical axis correction optical system and further suppress the in-plane light intensity distribution of the light from the illumination device from becoming uneven. It becomes.

  The projector of the present invention will be described below based on the embodiments shown in the drawings. In the following embodiments, a case where the optical axis of the light source device is inclined with respect to the designed system optical axis will be described as an example.

[Embodiment 1]
FIG. 1 is a diagram illustrating an optical system of a projector 1000 according to the first embodiment. FIG. 2 is a diagram for explaining the optical axis correcting optical system 700. FIG. In FIG. 2, the inclination of the optical axis 110ax of the light source device with respect to the designed system optical axis OC is exaggerated to facilitate understanding of the effects of the present invention.

  In the following description, the three directions orthogonal to each other are the z-axis direction (system optical axis OC direction in FIG. 1), the x-axis direction (direction parallel to the paper surface in FIG. 1 and perpendicular to the z-axis), and the y-axis direction. (A direction perpendicular to the paper surface in FIG. 1 and perpendicular to the z-axis).

  As shown in FIG. 1, the projector 1000 according to the first embodiment separates the illumination device 100 and the illumination light flux from the illumination device 100 into three color lights of red light, green light, and blue light and guides them to the illumination area. A color separation optical system 200 that emits light, a relay optical system 300 that guides blue light out of the three color lights separated by the color separation optical system 200, and the color separation optical system 200 and the relay optical system 300. The three liquid crystal devices 400R, 400G, and 400B as electro-optic modulation devices that modulate each of the three guided light colors according to image information, and the color light modulated by the three liquid crystal devices 400R, 400G, and 400B are combined. A cross dichroic prism 500 as a color synthesizing optical system, and light synthesized by the cross dichroic prism 500 with a screen SCR A projection optical system 600 for projecting onto the projection plane, an optical axis correction optical system 700 disposed in the illumination device 100, and an attitude adjustment device 702 capable of adjusting the attitude of the optical axis correction optical system 700. Projector.

  The illuminating device 100 includes a light source device 110 that emits an illumination light beam toward the illuminated region side, a concave lens 118 that is disposed on the illuminated region side of the light source device 110, and an illumination light beam emitted from the concave lens 118 into a plurality of partial light beams. A first lens array 120 having a plurality of first small lenses 122 for division, and a second lens array 130 having a plurality of second small lenses 132 corresponding to the plurality of first small lenses 122 of the first lens array 120. A polarization conversion element 140 that converts each partial light beam from the second lens array 130 into substantially one type of linearly polarized light having a uniform polarization direction and emits the light, and each partial light beam emitted from the polarization conversion element 140 is illuminated. And a superimposing lens 150 for superimposing the region.

  The light source device 110 includes an ellipsoidal reflector 114, an arc tube 112 having a light emission center near the first focal point of the ellipsoidal reflector 114, and light emitted from the arc tube 112 toward the illuminated region side to the arc tube 112. And a secondary mirror 116 that reflects toward the screen. The light source device 110 emits a light beam having the optical axis 110ax of the light source device as a central axis. The optical axis 110ax of the light source device is inclined in the x (−) direction with respect to the designed system optical axis OC (see FIG. 2).

  The arc tube 112 has a tube bulb portion and a pair of sealing portions extending on both sides of the tube bulb portion. The tube portion is made of quartz glass formed in a spherical shape, and includes a pair of electrodes disposed in the tube portion, mercury, a rare gas, and a small amount of halogen sealed in the tube portion. As the arc tube 112, various arc tubes can be employed, for example, a metal halide lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, or the like.

  The ellipsoidal reflector 114 includes a cylindrical neck that is inserted and fixed to one sealing portion of the arc tube 112, and a reflective concave surface that reflects light emitted from the arc tube 112 toward the second focal position. Have

  The secondary mirror 116 is a reflecting means that covers substantially half of the bulb portion of the arc tube 112 and is disposed to face the reflective concave surface of the elliptical reflector 114. The sub mirror 116 is inserted and fixed to the other sealing portion of the arc tube 112. The secondary mirror 116 returns the light emitted from the arc tube 112 that does not go to the ellipsoidal reflector 114 to the arctube reflector 114 and makes it incident on the ellipsoidal reflector 114.

  The concave lens 118 has a function as a collimating lens that emits the focused light from the ellipsoidal reflector 114 as substantially parallel light, and is configured to emit the light from the ellipsoidal reflector 114 toward the first lens array 120. Has been.

  The first lens array 120 has a function as a light beam splitting optical element that splits light from the concave lens 118 into a plurality of partial light beams, and a plurality of first small lenses 122 are arranged in a plane orthogonal to the system optical axis OC. It has a configuration arranged in a matrix of rows and columns. Although not illustrated, the outer shape of the first small lens 122 is similar to the outer shape of the image forming area of the liquid crystal devices 400R, 400G, and 400B.

  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 devices 400R, 400G, and 400B together with the superimposing lens 150. The second lens array 130 has substantially the same configuration as the first lens array 120, and 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 system optical axis OC. Have a configuration.

The polarization conversion element 140 is a polarization conversion element that emits the polarization direction of each partial light beam divided by the first lens array 120 as approximately one type of linearly polarized light having a uniform polarization direction.
The polarization conversion element 140 transmits light having one polarization component (for example, P polarization component) out of the illumination light flux from the light source device 110 and transmits light having the other polarization component (for example, S polarization component) to the system optical axis OC. A polarization separation layer that reflects in the vertical direction, a reflection layer that reflects light having the other polarization component reflected by the polarization separation layer in a direction parallel to the system optical axis OC, and one polarization that has passed through the polarization separation layer And a phase difference plate that converts light having a component into light having the other polarization component.

  The superimposing lens 150 condenses a plurality of partial light beams that have passed through the first lens array 120, the second lens array 130, and the polarization conversion element 140, and superimposes them on the vicinity of the image forming regions of the liquid crystal devices 400R, 400G, and 400B. It is an element. The superimposing lens 150 is arranged so that the optical axis of the superimposing lens 150 and the system optical axis OC substantially coincide. The superimposing lens 150 may be composed of a compound lens in which a plurality of lenses are combined.

  The color separation optical system 200 includes dichroic mirrors 210 and 220 and a reflection mirror 230. The color separation optical system 200 separates the illumination light beam emitted from the superimposing lens 150 into three color lights of red light, green light, and blue light, and the red light and green light are transmitted to the liquid crystal devices 400R and 400G. The light has a function of guiding to the relay optical system 300.

  The dichroic mirrors 210 and 220 are optical elements on which a wavelength selection film that reflects a light beam in a predetermined wavelength region and transmits a light beam in another wavelength region is formed on a substrate. The dichroic mirror 210 disposed in the front stage of the optical path is a mirror that reflects red light component light and transmits other color light component light. The dichroic mirror 220 disposed in the latter stage of the optical path is a mirror that transmits blue light component light and reflects green light component light.

  The light of the red light component reflected by the dichroic mirror 210 is bent by the reflection mirror 230 and enters the image forming area of the liquid crystal device 400R for red light via the condenser lens 430R. The condenser lens 430R is provided to convert each partial light beam from the superimposing lens 150 into a light beam substantially parallel to each principal ray. The other condenser lenses 430G and 430B are configured in the same manner as the condenser lens 430R.

  Of the green light component and blue light component light that has passed through the dichroic mirror 210, the green light component light is reflected by the dichroic mirror 220, passes through the condenser lens 300G, and the image forming area of the green light liquid crystal device 400G. Is incident on. On the other hand, the blue light component light passes through the dichroic mirror 220 and enters the relay optical system 300.

  The relay optical system 300 includes an incident side lens 310, an incident side reflection mirror 320, a relay lens 330, and an emission side reflection mirror 340, and transmits light of a blue light component transmitted through the dichroic mirror 220. It has a function of leading up to 400B. The light of the blue light component incident on the relay optical system 300 passes through the incident side lens 310 and is bent by the reflection mirror 320, and the pattern of the in-plane luminance distribution is inverted vertically and horizontally by the relay lens 330, and then the reflection mirror 340. And then passes through the condenser lens 430B and enters the image forming area of the blue light liquid crystal device 400B.

  The reason why such a relay optical system 300 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 lights, and thus the use of light due to light divergence or the like. This is to prevent a decrease in efficiency. The projector 1000 according to the first embodiment is configured as described above because the optical path length of blue light is long. However, the length of the optical path of red light is increased so that the relay optical system 300 is configured to transmit red light. A configuration for use in the optical path is also conceivable.

The liquid crystal devices 400 </ b> R, 400 </ b> G, and 400 </ b> B modulate the illumination light beam according to the image information and are the illumination target of the illumination device 100.
The liquid crystal devices 400R, 400G, and 400B are a pair of transparent glass substrates in which a liquid crystal that is an electro-optical material is hermetically sealed. For example, an incident light that will be described later is used according to given image information using a polysilicon TFT as a switching element. Modulates the polarization direction of one type of linearly polarized light emitted from the side polarizing plate.

  Although not shown here, incident-side polarizing plates are interposed between the condenser lenses 430R, 430G, and 430B and the liquid crystal devices 400R, 400G, and 400B, and the liquid crystal devices 400R, 400G, and 400B are disposed. Between the 400B and the cross dichroic prism 500, an exit side polarizing plate is interposed. The incident-side polarizing plate, the liquid crystal devices 400R, 400G, and 400B and the exit-side polarizing plate modulate light of each color light incident thereon.

  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 exit 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 the 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 a large screen image on the screen SCR.

  The optical axis correction optical system 700 is disposed between the concave lens 118 and the first lens array 120. The optical axis correcting optical system 700 is made of a plate-like glass member in which both the light incident surface 700i and the light emitting surface 700o are flat and the both surfaces are not in a parallel relationship. In the optical axis correcting optical system 700, the light incident surface 700i is substantially parallel to a virtual plane orthogonal to the system optical axis OC, and the light exit surface 700o is disposed at a predetermined angle with respect to the virtual plane. As shown in FIG. 2, the optical axis correction optical system 700 is configured so that the optical axis of the light L2 emitted with respect to the optical axis of the incident light L1 is inclined in a predetermined direction. Thereby, the optical axis of the illumination light beam inclined in the x (−) direction can be aligned with the system optical axis OC.

  The posture adjustment device 702 is an adjustment device for finely adjusting the posture (arrangement angle, rotation angle, etc.) of the optical axis correction optical system 700.

  The projector 1000 according to the first embodiment configured as described above has the above-described configuration in the optical path from the light source device 110 to the cross dichroic prism 500 (between the concave lens 118 and the first lens array 120). Since the optical axis correction optical system 700 is arranged, illumination emitted from the optical axis correction optical system 700 even when the optical axis 110ax of the light source device is inclined with respect to the designed system optical axis OC. It becomes possible to align the optical axis of the light flux with the system optical axis OC, and to suppress the in-plane light intensity distribution of the light from the illumination device 100 from becoming non-uniform. As a result, even if the in-plane luminance distribution pattern of one color light is inverted vertically and horizontally by the relay optical system 300, it is substantially the same as the in-plane luminance distribution pattern of the light before passing through the relay optical system 300. It becomes possible. That is, for the light irradiated to the image forming regions of the liquid crystal devices 400R, 400G, and 400B, the color light (blue light) that has passed through the relay optical system 300 and the color light (red light and light that has not passed through the relay optical system 300). The pattern of the in-plane luminance distribution is substantially equal to that of green light. As a result, it is possible to reduce the color unevenness of the image light projected on the screen SCR, particularly the white unevenness.

  In the projector 1000 according to the first embodiment, the optical axis correcting optical system 700 is made of a plate-like member in which both the light incident surface 700i and the light exit surface 700o are flat and the two surfaces are not in a parallel relationship. It is possible to incline the optical axis of the emitted light in a predetermined direction with respect to the optical axis of the light.

  In the projector 1000 according to the first embodiment, since the optical axis correction optical system 700 is disposed in the optical path upstream of the color separation optical system 200, one optical axis correction optical system 700 is disposed upstream of the color separation optical system 200. The in-plane luminance distribution in all optical paths can be made uniform at once by the optical axis correction optical system 700.

  Since the projector 1000 according to the first embodiment further includes a posture adjusting device 702 that can adjust the posture of the optical axis correction optical system 700, the posture (arrangement angle or the like) of the optical axis correction optical system 700 is finely adjusted. As a result, the in-plane light intensity distribution of the light from the illumination device 100 can be further suppressed from becoming non-uniform.

[Embodiment 2]
FIG. 3 is a diagram illustrating an optical system of the projector 1002 according to the second embodiment. In FIG. 3, the same members as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The projector 1002 according to the second embodiment basically has a configuration similar to that of the projector 1000 according to the first embodiment, but is different from the projector 1000 according to the first embodiment in that it further includes a dichroic filter for color correction. Different.

  That is, in the projector 1002 according to the second embodiment, a dichroic filter 704 for color correction is arranged on the light incident surface 700 i of the optical axis correction optical system 700 as shown in FIG. The dichroic filter 704 for color correction is a filter for widening the color gamut and reducing the black floating level so that a screen having a color tone suitable for movie viewing or the like is displayed.

  As described above, the projector 1002 according to the second embodiment is different from the projector 1000 according to the first embodiment in that it further includes a dichroic filter for color correction. However, as in the case of the projector 1000 according to the first embodiment, Since the optical axis correction optical system 700 is provided, the optical axis of the illumination light beam emitted from the optical axis correction optical system 700 is changed even when the optical axis 110ax of the light source device is inclined with respect to the designed system optical axis OC. It becomes possible to align with the system optical axis OC, and it becomes possible to suppress the in-plane light intensity distribution of the light from the illumination device 102 from becoming uneven. As a result, it is possible to reduce the color unevenness of the image light projected on the screen SCR, particularly the white unevenness.

  Further, in the projector 1002 according to the second embodiment, since the dichroic filter 704 for color correction is arranged in the optical axis correction optical system 700, the white unevenness of the projected image is used even when used for movie appreciation. Can be reduced.

  The projector 1002 according to the second embodiment has the same configuration as the projector 1000 according to the first embodiment except that it further includes a dichroic filter for color correction. Of which, it has the relevant effect.

[Embodiment 3]
FIG. 4 is a diagram illustrating an optical system of the projector 1004 according to the third embodiment. In FIG. 4, the same members as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The projector 1004 according to the third embodiment basically has a configuration similar to that of the projector 1000 according to the first embodiment, but the configuration of the optical axis correction optical system is different from that of the projector 1000 according to the first embodiment.

  That is, the projector 1004 according to the third embodiment includes an optical axis correction optical system 710 in which the concave lens 118 described in the first embodiment and the optical axis correction optical system 700 are integrated as shown in FIG.

  The optical axis correcting optical system 710 is made of a glass member in which the light incident surface 710i is a lens surface having a curvature and the light exit surface 710o is a flat surface. Since the optical axis of the light incident surface 710i, which is a lens surface, is inclined with respect to the normal of the light exit surface 710o, which is a flat surface, the light exit surface 710o emits light with respect to the optical axis of the light incident on the light incident surface 710i. The optical axis of the emitted light can be emitted in a predetermined direction. Similar to the lens surface of the concave lens 118 described in the first embodiment, the light incident surface 710i of the optical axis correction optical system 710 has a function of emitting the focused light from the ellipsoidal reflector 114 as substantially parallel light (light incident surface). The optical axis of 710i substantially coincides with the optical axis 110ax of the light source device). The optical axis correction optical system 710 is disposed in a state where the light exit surface 710o is inclined at a predetermined angle with respect to a virtual plane orthogonal to the system optical axis OC. Similar to the optical axis correction optical system 700 described in the first embodiment, the optical axis correction optical system 710 is incident so that the optical axis of light emitted from the light emission surface 710 o is aligned with the system optical axis OC. The optical axis of the light emitted with respect to the optical axis of the light (optical axis 110ax of the light source device) is inclined and emitted in a predetermined direction.

  Further, the optical axis correction optical system 710 is provided with an attitude adjustment device 712 for finely adjusting the attitude (rotation angle, etc.) of the optical axis correction optical system 710.

  As described above, the projector 1004 according to the third embodiment differs from the projector 1000 according to the first embodiment in the configuration of the optical axis correction optical system, but the incident light is the same as in the projector 1000 according to the first embodiment. Since the optical axis correction optical system 710 is configured so that the optical axis of the light emitted with respect to the optical axis of the optical system is emitted in a predetermined direction, the optical axis 110ax of the light source device with respect to the designed system optical axis OC. Can be aligned with the system optical axis OC, and the in-plane light intensity distribution of the light from the illuminating device 104 can be obtained by aligning the optical axis of the illumination light beam emitted from the optical axis correction optical system 710 with the system optical axis OC. It becomes possible to suppress non-uniformity. As a result, it is possible to reduce the color unevenness of the image light projected on the screen SCR, particularly the white unevenness.

  The projector 1004 according to the third embodiment has the same configuration as the projector 1000 according to the first embodiment except that the configuration of the optical axis correction optical system is different. Therefore, the effect of the projector 1000 according to the first embodiment is obtained. Of which, it has the relevant effect.

  The projector of the present invention has been described based on each of the above embodiments. However, the present invention is not limited to each of the above embodiments, and can be implemented in various modes without departing from the scope of the invention. For example, the following modifications are possible.

(1) In the projectors 1000 to 1004 according to the above-described embodiments, the case where the optical axis 110ax of the light source device is inclined in the x (−) direction with respect to the designed system optical axis OC has been described as an example. However, the present invention is not limited to this. For example, when the optical axis 110ax of the light source device is tilted in the x (+) direction, in the y (+) direction, or in the y (−) direction, the x axis and the y direction are further increased. Even when tilted in both directions, the optical axis of the illumination light beam emitted from the optical axis correction optical system can be aligned with the system optical axis OC by using the optical axis correction optical system corresponding to the tilt. It is possible to suppress the in-plane light intensity distribution of light from the illumination device from becoming non-uniform.

(2) In the projectors 1000 to 1004 according to the above-described embodiments, the case where the optical axis 110ax of the light source device is inclined with respect to the designed system optical axis OC has been described as an example. The present invention is not limited, and the present invention can also be applied to the case where the optical axis of the illumination device is inclined with respect to the designed system optical axis OC.

(3) In the projectors 1000 and 1002 according to the first and second embodiments, the optical axis correcting optical system is a plate-like member in which both the light incident surface and the light emitting surface are flat and the two surfaces are not in a parallel relationship. In the projector 1004 according to the third embodiment, the light incident surface is a lens surface having a curvature, the light exit surface is a flat surface, and the light incident surface is a lens surface. Although the optical axis correction optical system 710 in which the optical axis is inclined with respect to the normal of the light exit surface which is a plane has been described as an example, the present invention is not limited to this. As the optical axis correction optical system, both the light incident surface and the light exit surface are lens surfaces having curvature, and the optical axis of the lens surface of the light incident surface is inclined with respect to the optical axis of the lens surface of the light exit surface. An optical axis correction optical system may be used.

(4) In the projectors 1000 and 1002 according to the first and second embodiments, the optical axis correction optical system 700 is configured so that the light incident surface 700i is substantially parallel to a virtual plane orthogonal to the optical axis of the illuminating device. Although the surface 700o is disposed so as to be inclined at a predetermined angle with respect to the virtual plane, the present invention is not limited to this, and the light emission surface 700o is relative to the virtual plane orthogonal to the optical axis of the illumination device. So that the light incident surface 700i is inclined at a predetermined angle with respect to the virtual plane, and both the light incident surface 700i and the light exit surface 700o are predetermined with respect to the virtual plane. You may arrange | position so that it may be in the state inclined at an angle.

(5) In the projector 1004 according to the third embodiment, the optical axis correction optical system 710 is emitted from the light emission surface with respect to the optical axis correction function (the optical axis of light incident on the light incident surface) on the plane side. However, the present invention is not limited to this, and the lens surface side may be provided with the optical axis correction function.

(6) In the projector 1004 according to the third embodiment, the optical axis correction optical system 710 in which the light exit surface (the surface that is not the lens surface) of the concave lens 118 has an optical axis correction function has been described as an example. However, the present invention is not limited to this. For example, one side or both sides of the superimposing lens may have an optical axis correction function, or one side of the first lens array or the second lens array may have an optical axis correction function. When it has, you may give an optical axis correction | amendment function to the single side | surface or both surfaces of the said windshield.

(7) In the projectors 1000 to 1004 according to the above embodiments, the case where one optical axis correction optical system is used has been described as an example. However, the present invention is not limited to this, and two or more projectors are used. The in-plane light intensity distribution of the light from the illumination device may be suppressed from becoming non-uniform using the optical axis correcting optical system.

(8) In the projectors 1000 to 1004 according to the above embodiments, the optical axis correction optical systems 700 and 710 are disposed between the light source device 110 and the first lens array 120 in the illumination devices 100 to 104. However, the present invention is not limited to this, and may be disposed at other positions in the illumination devices 100 to 104, or may be disposed in the color separation optical system 200 or the relay optical system 300. Also good. When arranged in the color separation optical system 200, for example, an optical axis correction optical system is arranged between the dichroic mirror 210 and the reflection mirror 230, and an optical axis correction is made between the dichroic mirror 210 and the dichroic mirror 220. An optical system may be arranged to align the in-plane luminance distribution pattern for the light irradiated to the image forming area of each liquid crystal device.

(9) In the projector 1000 according to the first embodiment, the concave lens 118 and the optical axis correcting optical system 700 are spaced apart from each other, but the present invention is not limited to this, and the concave lens 118 and the light The axis correction optical system 700 may be bonded via an adhesive.

(10) In the projectors 1000 to 1004 according to the above-described embodiments, the secondary mirror is used as the reflecting means disposed in the arc tube. However, the present invention is not limited to this, and the reflecting film is used as the reflecting means. It is also preferable to use. In the projectors 1000 to 1004 according to the above-described embodiments, the projector in which the secondary mirror as the reflecting means is disposed on the arc tube is described as an example. However, the present invention is not limited to this. In addition, the present invention can be applied to a projector in which a secondary mirror is not provided.

(11) In the projectors 1000 and 1002 according to the first and second embodiments, the light source device including the ellipsoidal reflector is used as the light source device. However, the present invention is not limited to this, and the parabolic reflector. It is also preferable to use a light source device comprising In this case, the concave lens may not be provided.

(12) In projectors 1000 to 1004 according to the above embodiments, a lens integrator optical system including a lens array is used as the light uniformizing optical system. However, the present invention is not limited to this, and a rod member is used. A rod integrator optical system made of can also be preferably used.

(13) The projectors 1000 to 1004 according to the above embodiments are transmissive projectors, but the present invention is not limited to this. The present invention can also be applied to a reflection type projector. Here, “transmission type” means that an electro-optic modulation device as a light modulation means, such as a transmission type liquid crystal device, transmits light, and “reflection type” This means that an electro-optic modulation device as a light modulation means, such as a reflective liquid crystal 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.

(14) In the projectors 1000 to 1004 according to the above-described embodiments, the projector using the three liquid crystal devices 400R, 400G, and 400B has been described as an example. However, the present invention is not limited to this, and 1 The present invention can also be applied to a projector using two, four, or four or more liquid crystal devices.

(15) In projectors 1000 to 1004 according to the above-described embodiments, the liquid crystal device is used as the electro-optic modulation device, but the present invention is not limited to this. In general, the electro-optic modulation device may be any device that modulates incident light in accordance with 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.

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

FIG. 3 shows an optical system of the projector 1000 according to the first embodiment. The figure shown in order to demonstrate the optical axis correction | amendment optical system 700. FIG. FIG. 6 is a diagram showing an optical system of a projector 1002 according to a second embodiment. FIG. 10 shows an optical system of a projector 1004 according to a third embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100,102,104 ... Illuminating device, 110ax ... Optical axis of light source device, 110 ... Light source device, 112 ... Light emitting tube, 114 ... Ellipsoidal reflector, 116 ... Secondary mirror, 118 ... Concave lens, 120 ... First lens array, 122 ... 1st small lens, 130 ... 2nd lens array, 132 ... 2nd small lens, 140 ... Polarization conversion element, 150 ... Superimposing lens, 200 ... Color separation optical system, 210, 220 ... Dichroic mirror, 230, 320, 340 DESCRIPTION OF SYMBOLS ... Reflection mirror, 300 ... Relay optical system, 310 ... Incident side lens, 330 ... Relay lens, 400R, 400G, 400B ... Liquid crystal device, 430R, 430G, 430B ... Condensing lens, 500 ... Cross dichroic prism, 600 ... Projection optics System, 700, 710 ... Optical axis correction optical system, 700i, 710i ... (of optical axis correction optical system) Light entrance surface, 700o, 710o (light axis correction optical system) light exit surface, 702, 712 ... Attitude adjustment device, 704 ... Dichroic filter (for color correction), 1000, 1002, 1004 ... Projector, L1, L2 ... Light, OC ... System optical axis, SCR ... Screen

Claims (7)

An illumination device having a light source device for emitting illumination light flux;
A color separation optical system that separates light from the illumination device into a plurality of color lights and guides the light to an illuminated area;
A relay optical system having a relay lens that guides one color light of the plurality of color lights separated by the color separation optical system to an illuminated area;
A plurality of electro-optic modulators that respectively modulate a plurality of color lights guided by the color separation optical system and the relay optical system according to image information;
A color synthesizing optical system that synthesizes each color light modulated by the plurality of electro-optic modulation devices;
A projection optical system for projecting image light synthesized by the color synthesis optical system;
An optical axis correction optical system disposed in an optical path from the light source device to the color synthesis optical system,
The optical axis correction optical system is configured to emit an optical axis of light emitted from the optical axis correction optical system inclined in a predetermined direction with respect to an optical axis of light incident on the optical axis correction optical system. A projector characterized by that. The projector according to claim 1, wherein
2. The projector according to claim 1, wherein the optical axis correcting optical system is made of a plate-like member in which both the light incident surface and the light emitting surface are flat and the two surfaces are not parallel to each other. The projector according to claim 2,
A projector characterized in that a dichroic filter for color correction is disposed on the plate member. The projector according to claim 1, wherein
In the optical axis correcting optical system, one of the light incident surface and the light emitting surface is a lens surface having a curvature, the other surface is a plane, and the optical axis of the lens surface is perpendicular to the plane. A projector characterized by tilting. The projector according to claim 1, wherein
The optical axis correction optical system is a lens surface in which both of the light incident surface and the light exit surface have a curvature, and the optical axis of the lens surface of the light incident surface is relative to the optical axis of the lens surface of the light exit surface. A projector characterized by tilting. In the projector according to any one of claims 1 to 5,
The projector according to claim 1, wherein the optical axis correction optical system is disposed in an optical path preceding the color separation optical system. In the projector according to any one of claims 1 to 6,
A projector further comprising an attitude adjustment device capable of adjusting an attitude of the optical axis correction optical system.

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