JP2001013603A - Optical device and liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make easily executable the angle adjustment of a reflection means and the position adjustment thereof associated with the angle adjustment with a simple constitution by setting a rotation center for simultaneously adjusting the incident angle and the position of the reflection means at a specified position. SOLUTION: The rotation center C for simultaneously adjusting the incident angle and the position of a reflection mirror is set at the extension of the reflection surface of the reflection mirror and at a position where an irradiating position P obtained when the incident angle is adjusted can be made to coincide with an irradiating position obtained before the adjustment. That means, a triangle O-A'-B' being similar to a triangle O-A-B is obtained and an intersection point C on the extension of the reflection mirror surface is passed through a side A'-B'. By setting the rotation center C of the reflection mirror on the straight line A'-B', the condition of the angle required for passing the optical axis through the position P and the condition of positional deviation associated with the angle adjustment are satisfied. When the adjusting angle of the reflection mirror is large, the position of the intersection point C on the extension of the reflection mirror is deviated but it does not become a problem in the case of fine adjustment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical apparatus, and more particularly, to an adjustment of an incident angle of a reflecting means with respect to an illumination optical axis and a reflecting means for correcting a movement of an irradiation position due to the adjusting of the incident angle. An object of the present invention is to realize a configuration in which these adjustments can be easily performed in a liquid crystal projector having a configuration for simultaneously performing position adjustment.

[0002]

2. Description of the Related Art Conventionally, when illuminating light is applied to a panel surface of a single-panel reflective liquid crystal projector, white illumination light converted into a parallel light beam is R (red), G (green), B (white) by a dichroic mirror.
(Blue), and each color was incident on the panel surface at an angle. The incident R, G, and B lights are firstly transmitted to the R, G, and B light components arranged at different positions on the liquid crystal panel surface by the microlens array disposed on the front surface of the reflective liquid crystal panel.
An image is formed on a pattern dedicated to B. By controlling the R, G, and B patterns (ON-OFF, etc.), the reflected light of the required color passes through the microlens again, and is projected on the screen via the projection lens. The projection lens is focused substantially on the microlens array surface and projects it on a screen. Three patterns of colors are synthesized by the colors (ratio of R, B, and G) coming out of each microlens to constitute one pixel.
At that time, it is important to finely adjust the angle of the dichroic mirror to find an incident angle at which color mixing does not occur. If the angle of the incident light is shifted, the adjacent pattern is irradiated, or the reflected light enters the adjacent microlens, causing color mixing.

[0003] In view of the above, in order to adjust the angle of the dichroic mirror and prevent color mixture from occurring, a configuration as disclosed in Japanese Patent Application Laid-Open No. H4-60538 shown in FIG. Proposed. In the configuration shown in FIG. 5, the central mirror is fixed at 45 degrees,
The remaining two mirrors are adjustable in illumination angle, and are held by the dowels of “fixed” 30 and “elastic pressure-resisting” 31 at the lower center of the center.

[0004]

However, in the prior art described in Japanese Patent Application Laid-Open No. 4-60538, the mirror is adjusted with the center at the center of rotation.
The irradiation position shifts. Therefore, another conventional example proposes providing a cam mechanism and a link mechanism so that the angle adjustment of the mirror and the position adjustment of the mirror for correcting the irradiation position shift accompanying the angle adjustment are simultaneously performed. Have been. However, in this case, since a cam mechanism and a link mechanism are required, there is a problem in that the configuration is extremely complicated.

Accordingly, the present invention solves the above-mentioned problems in the prior art, and in an optical device having a reflecting means for reflecting at least a part of light of a light beam and bending an illumination light path, adjusting the angle of the reflecting means, It is an object of the present invention to provide an optical device capable of adjusting the position of a reflecting means in accordance with an angle adjustment with a simpler configuration than a conventional one.

[0006]

In order to achieve the above object, the present invention is characterized in that the optical device is constructed as in the following (1) to (6). (1) An optical device according to the present invention includes a light source, an optical unit that converts a luminous flux into a parallel luminous flux, and a reflecting unit that reflects at least a part of the light of the luminous flux to bend an illumination optical path, and the reflecting unit. In the optical device for illuminating the member to be illuminated, the adjustment of the incident angle with respect to the illumination optical axis and the position adjustment of the reflecting means for correcting the movement of the irradiation position accompanying the adjustment of the incident angle are performed simultaneously. The center of rotation for simultaneously performing the adjustment of the incident angle and the position adjustment in the reflection means,
It is characterized in that it is provided on an extension of the reflection surface of the reflection means, at a position where the irradiation position when the incident angle of the reflection means is adjusted can be the same as before the adjustment. (2) The optical device according to the present invention includes a light source, an optical unit that converts the emitted light beam into a parallel light beam, and a reflecting unit that reflects at least a part of the light of the light beam to bend the illumination light path, and the reflecting unit. In the optical device for illuminating the member to be illuminated, the adjustment of the incident angle with respect to the illumination optical axis and the position adjustment of the reflecting means for correcting the movement of the irradiation position accompanying the adjustment of the incident angle are performed simultaneously. The center of rotation for simultaneously performing the adjustment of the incident angle and the position adjustment in the reflection means,
The illumination device is characterized in that the illumination position is provided on a line perpendicular to the incident optical axis of the illumination light and at which the irradiation position when the incident angle of the reflection means is adjusted can be the same as before the adjustment. (3) The optical device according to the present invention, wherein the rotation center of the reflection unit is a light source, an optical unit that converts the emitted light beam into a parallel light beam, and a reflection unit that reflects at least a part of the light of the light beam and bends the illumination light path. Adjusting the angle of incidence of the reflecting means with respect to the illumination optical axis, and simultaneously adjusting the position of the reflecting means for correcting the movement of the irradiation position associated with the adjusting of the angle of incidence, with respect to the member to be illuminated. In the optical device for illuminating, the irradiation position when the incident angle of the reflecting means is adjusted on the extension of the reflecting surface of the reflecting means to simultaneously perform the adjustment of the incident angle and the position adjustment in the reflecting means. Is a rotation center provided at a position where it is possible to match with before the adjustment,
In order to simultaneously perform the adjustment of the incident angle and the position adjustment in the reflection unit, the irradiation position when the incident angle of the reflection unit is adjusted on the perpendicular line of the incident optical axis of the illumination light before the adjustment. Is provided on a straight line connecting the rotation center provided at a position where the rotation center can be matched. (4) The optical device according to the present invention is an optical device having a reflecting means for illuminating an illuminated area with reflected light, wherein an incident angle of at least a part of the reflected light to the area is not substantially changed in an illumination range. It is characterized by having a mechanism for rotating one or a plurality of mirrors of the reflection means around a rotation axis set at a position distant from the reflection means so as to be changed. (5) A liquid crystal display device according to the present invention includes any one of the above-described optical devices according to the present invention, and illuminates a liquid crystal panel having a microlens array on a light incident surface with the reflected light. (6) The liquid crystal display device according to the present invention is characterized in that the reflecting means includes a plurality of dichroic mirrors as the mirror, and reflects red, green, and blue lights toward the microlens array from different directions. I have.

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing the principle of mirror angle adjustment in the present invention. The incident light is reflected by the reflection mirror and irradiates the panel surface. Here, the irradiation position P of the reflected light is set as follows. P
Is a point through which the optical axis of the reflected light passes. The reflected light at the position where the reflection mirror is finely adjusted also passes through P. Δθ reflection mirror
Fine adjustment changes the luminous flux by 2 × δθ, which is the same location P
Has been irradiated.

In order to satisfy this condition, the triangle O
A triangle OA'B 'similar to AB may be obtained, and the intersection C on the extension of the reflection mirror surface may pass on the side A'B'. By providing the rotation center of the reflection mirror on the straight line A′B ′, it is possible to satisfy the condition of the angle for the optical axis to pass through P and the condition of the positional deviation accompanying the angle adjustment. When the adjustment angle of the reflection mirror is large, the position of the intersection C on the extension of the reflection mirror is shifted, but there is no problem in the case of fine adjustment.
When the rotation center is at A ', the direction of fine movement of the reflection mirror substantially coincides with the incident direction, so that the reflection mirror does not deviate from the light beam of the incident light. If the rotation center C is brought to the shortest distance between A'B 'and the point O, the distance between the reflection mirror and the rotation center can be minimized.

However, in the case where the rotation center is not provided at A 'due to the optical arrangement, it is necessary to provide the rotation center at an appropriate point on the straight line according to the arrangement of the surrounding optical system and the like. . Further, even when the adjustment angle of the reflection mirror is relatively large, if the intersection point C of the extension of the reflection mirror is provided at an average intersection point in the angle adjustment range of the reflection mirror, there is a slight deviation of the irradiation position P. Meet the purpose of the adjustment.

[0010]

Embodiments of the present invention will be described below.
FIG. 2 shows an embodiment of the present invention applied to a single-panel reflective liquid crystal panel. Reference numeral 1 denotes an illumination system for irradiating a parallel light beam to the panel. 2 and 3 are reflection dichroic mirrors. Reference numeral 4 denotes a polarizing plate for controlling the polarization direction. Reference numeral 5 denotes a polarizing beam splitter. Reference numeral 6 denotes a liquid crystal panel with a micro lens array. Reference numeral 7 denotes a projection lens focused on a substantially microlens array surface. Reference numeral 8 denotes a screen surface for projecting a substantially microlens surface.

The incident light from the illumination system is incident on the reflection dichroic mirrors 2 and 3 with the polarization direction being aligned by the polarizing plate 4. The reflected light that has been color-separated into R, G, and B enters a polarizing beam splitter, is bent at a reflection surface, and enters a liquid crystal panel with a microlens array. FIG. 2 shows examples of R and G reflected light. The reflected light carrying the image signal from the liquid crystal panel with the microlens array is rotated in the polarization direction, passes through the beam splitter again, enters the projection lens, and is projected on the screen surface.

FIG. 3 shows the structure of a liquid crystal panel with a microlens array, and FIG. 4 shows the operation of the microlens. 10
Is a panel on which patterns for driving the liquid crystal are arranged. 12
Is a liquid crystal. Reference numeral 11 denotes a micro lens array. The reflected light is controlled by controlling the liquid crystal on the pattern. The R incident at an angle forms a red light source image on the pattern dedicated to R on the panel surface by the microlens on the right. When the liquid crystal is ON, R is reflected and emitted from the microlenses forming the pixels. Similarly, B enters the upper adjacent microlens and exits from the microlens forming the same pixel. G enters vertically and exits vertically. R,
The colors are synthesized by controlling the G and B reflectances.

If the incident angles of R, B, and G deviate from normal or there is a dimensional tolerance of the liquid crystal panel with the microlens array, a part of the light that should be emitted from the adjacent microlens will cause the original pixel to be out. The resulting microlens is emitted and becomes a color mixture, and the projected image deteriorates. Therefore, in order to prevent color mixing, it is necessary to accurately adjust the angle of the reflection dichroic mirror. Reference numeral 21 is a holder for holding the R, and 22 is a holder for holding the G dichroic mirror. In this embodiment, the angle between R and B (not shown) is adjusted. The center of rotation of the R dichroic mirror is indicated by point c on the holder. 23 is a screw for fine adjustment, and 24 is a return spring. After the angle adjustment by moving the fine adjustment screw is completed, the holder 21 is fixed with bolts.

[0014]

As described above, according to the present invention, in an optical device having a reflecting means for reflecting at least a part of light of a light beam and bending an illumination optical path, the angle adjustment of the reflecting means and the angle adjustment And the position adjustment of the reflection means accompanying
It can be easily performed and can be widely applied to devices that require such optical adjustment.However, it is particularly applicable to a liquid crystal projector having a single-panel reflective liquid crystal panel so as to prevent deterioration in image quality due to color mixing. By configuring
More effect can be exhibited.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of angle adjustment of a mirror.

FIG. 2 is a diagram showing a configuration of an embodiment of the present invention applied to a single-panel reflective liquid crystal panel.

FIG. 3 is a diagram showing a structure of a liquid crystal panel with a microlens array.

FIG. 4 is a view showing the operation of a micro lens.

FIG. 5 is a diagram illustrating a configuration related to angle adjustment of a dichroic mirror in a conventional single-panel reflective liquid crystal projector.

[Explanation of symbols]

 1: Illumination system for irradiating a panel with parallel light flux 2: R reflection dichroic mirror 3: G reflection dichroic mirror 4: Polarizing plate for controlling polarization direction 5: Polarizing beam splitter 6: Liquid crystal panel with microlens array 7: Projection lens 8: Screen surface 10: Panel on which patterns for driving liquid crystal are arranged 11: Micro lens array 12: Liquid crystal 21: Holder holding R dichroic mirror 22: Holder holding G dichroic mirror 23: Fine adjustment Screw 24: Return spring 30: Fixed dowel 31: Elastic pressure dowel

Claims (6)

[Claims] 1. A light source, optical means for converting a light beam into a parallel light beam, and reflecting means for reflecting at least a part of the light of the light beam and bending an illumination light path, wherein the reflecting means with respect to the illumination optical axis An optical device that illuminates a member to be illuminated by simultaneously adjusting the incident angle and adjusting the position of the reflecting unit for correcting the movement of the irradiation position due to the incident angle adjustment, wherein The center of rotation for simultaneously performing the angle adjustment and the position adjustment is on the extension of the reflection surface of the reflection unit, and the irradiation position when the incident angle of the reflection unit is adjusted is the same as that before the adjustment. An optical device, wherein the optical device is provided at a position where the optical device can be operated. 2. A light source, optical means for converting a light beam into a parallel light beam, and reflecting means for reflecting at least a part of the light of the light beam and bending an illumination light path, wherein the reflecting means with respect to the illumination optical axis. An optical device that illuminates a member to be illuminated by simultaneously adjusting the incident angle and adjusting the position of the reflecting unit for correcting the movement of the irradiation position due to the incident angle adjustment, wherein The center of rotation for simultaneously performing the angle adjustment and the position adjustment is on a perpendicular line to the incident optical axis of the illumination light, and the irradiation position when the incident angle of the reflection unit is adjusted is the same as the position before the adjustment. An optical device, wherein the optical device is provided at a position where matching is possible. 3. The rotation center of the reflecting means includes a light source, an optical means for converting the emitted light beam into a parallel light beam, and a reflecting means for reflecting at least a part of the light of the light beam and bending an illumination optical path, In an optical device that illuminates a member to be illuminated, the adjustment of the angle of incidence of the reflecting means with respect to the illumination optical axis and the adjustment of the position of the reflecting means for correcting the movement of the irradiation position accompanying the adjustment of the angle of incidence are performed simultaneously. In order to simultaneously perform the adjustment of the incident angle and the position adjustment in the reflecting unit, the irradiation position when the incident angle of the reflecting unit is adjusted on the extension of the reflecting surface of the reflecting unit before the adjustment. And a rotation center provided at a position where it can be matched with the reflection light on the perpendicular to the incident optical axis of the illumination light to simultaneously perform the adjustment of the incident angle and the position adjustment in the reflection means. Entering means Irradiation position when adjusting the angle, optical apparatus, characterized in that it is provided connecting it on a straight line, the rotation center provided on the can and a position that coincides with the front the adjustment. 4. An optical device having a reflection means for illuminating an illuminated area with reflected light, wherein an incident angle of at least a part of the reflected light to the area is changed without substantially changing an illumination range. An optical apparatus, comprising: a mechanism for rotating one or more mirrors of the reflection means around a rotation axis set at a position distant from the reflection means. 5. A liquid crystal display comprising the optical device according to claim 1, wherein the reflected light illuminates a liquid crystal panel having a microlens array on a light incident surface. apparatus. 6. The apparatus according to claim 5, wherein said reflecting means includes a plurality of dichroic mirrors as said mirrors, and reflects red, green and blue lights toward said microlens array from different directions. Liquid crystal display device.