JP2792073B2 - LCD projector - Google Patents

Description

The present invention relates to a liquid crystal projector.

[Prior Art] Conventional light source lamp, color separation optical system, illumination optical system, liquid crystal panel, image combining optical system, projection optical system 3
The plate-type LCD video projector separates the light generated from the light source lamp into three colors of blue, green and red by a dichroic mirror of a color separation optical system, and converts the light into three liquid crystal panels for blue, green and red. Irradiate. The light modulated by the liquid crystal panel is subjected to image synthesis by a dichroic prism of an image synthesis optical system. Next, this is projected on a screen by a projection lens to obtain an image.

Unlike liquid crystal video projectors, which do not require convergence adjustment during setting, unlike CRT dual-tube video projectors, it is necessary to precisely align the three liquid crystal panels during manufacturing. Conventionally, in this adjustment, the alignment adjustment is performed with all three liquid crystal panels for blue, green, and red being free.

[Problems to be Solved by the Invention] However, in the alignment adjustment of the conventional liquid crystal video projector described above, the alignment adjustment is performed by setting all three liquid crystal panels for blue, green, and red free. There is a problem that it takes time to perform the alignment adjustment. Therefore, in the present invention, the alignment adjustment mechanism of the liquid crystal panel is provided for two liquid crystal panels, and the remaining one is provided.
An object of the present invention is to reduce the number of liquid crystal panel alignment adjustment steps by employing an alignment adjustment system in which one liquid crystal panel is fixed.

[Means for Solving the Problems] A liquid crystal projector of the present invention comprises: first, three liquid crystal panels for modulating three color lights;
A liquid crystal projector comprising: synthesizing optical means for synthesizing the color lights modulated by the three liquid crystal panels; and projection optical means for projecting the light synthesized by the synthesizing optical means. The liquid crystal panel is arranged at a fixed position with respect to the combining optical means, and the second and third liquid crystal panels are provided with a mechanism for adjusting the arrangement position with respect to the first liquid crystal panel.

Secondly, the arrangement position adjusting mechanism includes means for adjusting the vertical direction, the horizontal direction, and the depth of focus direction.

Third, the combining optical means is composed of prisms having reflection surfaces having different reflection characteristics arranged in a cross shape, and the three liquid crystal panels are arranged on three surfaces of the prism. .

Fourth, among the three surfaces of the prism, the surface facing the surface on which the projection optical unit is disposed is the first surface.
Is fixedly arranged, and the second and third liquid crystal panels are arranged with the adjustment mechanism on the remaining two surfaces.

 Hereinafter, the present invention will be described in detail with reference to examples.

Embodiment FIG. 1 shows an embodiment of the present invention.

FIG. 3 is a conceptual diagram of a configuration of a three-panel liquid crystal video projector (liquid crystal projector). First, the third
The configuration of a three-panel liquid crystal video projector (liquid crystal projector) in the figure will be described.

Light generated from the light source lamp 101 is collected by the lamp reflector 102 and emitted forward. This light is separated into blue light and amber light by a blue reflection dichroic mirror 301. The separated amber light is separated into green light and red light by a green reflection dichroic mirror 302. The separated blue light is guided to the liquid crystal panel by the reflection-enhancing mirror 303, the green light is directly guided by the reflection-enhancing mirrors 304 and 305, and the red light is guided to the liquid crystal panel by the reflection-enhancing mirrors 304 and 305. LCD panel for blue 31
1. Each color light applied to the green liquid crystal panel 312 and the red liquid crystal panel 313 is image-modulated by the liquid crystal panel. Each color light transmitted through the liquid crystal panel is image-combined by the dichroic prism 305. This dichroic prism is one in which a blue reflecting dichroic film and a red reflecting dichroic film are arranged in a cube-shaped glass block so as to intersect diagonally in a cross shape. Here, each color light transmitted through the liquid crystal panel is synthesized. The light that has passed through the dichroic prism is projected on a screen 309 by a projection lens 308. Thus, a full-color image is obtained.

However, when combining images on the dichroic prism 306, the liquid crystal panel 311 for blue and the liquid crystal panel 312 for green
If the geometrical positional relationship of the liquid crystal panel 313 for red and the color liquid crystal panel 313 does not completely match, a color shift occurs on the screen. For this purpose, an alignment adjustment for adjusting the geometrical positional relationship at the time of manufacturing is performed. Since this alignment adjustment is performed in three directions of the vertical direction, the horizontal direction, and the depth of focus direction of each liquid crystal panel, it takes a lot of man-hours. If the reference liquid crystal panel module is not properly fixed, the remaining two liquid crystal panel modules may not be aligned outside the adjustment range.

Therefore, in this embodiment, by fixing the green panel module and fitting the blue panel module and the red panel module to the green panel module, the number of alignment steps is reduced to about two-thirds. In addition, since the reference green panel module can be fixed at the center position, it is possible to reduce troubles that the remaining blue panel module and red panel module cannot be adjusted in alignment adjustment.

FIG. 1 is an exploded perspective view of a liquid crystal panel module according to the present invention. This optical head includes a blue panel module, a green panel module, a red panel module, a dichroic prism, and a projection lens.

The fan housing 220 has a role of a cover for a fan for cooling the liquid crystal panel module and a role of supporting the entire optical head. Base plate 221 fixed on this
Has a role of positioning each optical component and structural component. A dichroic prism 235 is fixed to the center of the base plate 221. A front plate 223 and a rear plate 222 are arranged as structural materials before and after the dichroic prism 235, and each component is fixed by the upper plate 225. The projection lens 224 is fixed to the front plate 223.

Next, the panel module will be described. Taking the panel module for blue as an example, the liquid crystal panel for blue 31
1 is configured to be sandwiched together with an insulating sheet 313 by a panel module fixing plate 312 and a panel fixing plate 314. Green panel module 302,
The red panel module 303 has these components assembled.

Green panel module 302 is directly fixed to rear plate 222 by panel module fixing screws 420.
It has no adjustment mechanism and does not move. Since this panel module serves as a reference for alignment adjustment, alignment adjustment is performed by matching another panel module with the green panel module.

The blue panel module and the red panel module 302 have an adjustment mechanism. It has an adjustment mechanism in the vertical direction, the horizontal direction, and the depth of focus direction for each liquid crystal panel. These panel modules are fixed to the upper plate 225 by tightening the left-right adjustment screw 421.

In the vertical direction, the liquid crystal panel is set free by loosening the four vertical adjustment screws 424, and the liquid crystal panel is aligned with the reference panel. Then, the vertical adjustment screw 424 is tightened.

In the left-right direction, loosen the two left-right adjustment screws 421 to free the liquid crystal panel module and fit it to the reference panel.
The procedure of tightening and fixing is carried out.

In the depth of focus direction, the position of the liquid crystal panel module is adjusted by tightening the two screws 421 for adjusting the depth of focus direction to adjust the position to the reference panel.

FIG. 2 shows a panel module adjustment mechanism of a conventional optical head. The green panel module has exactly the same adjustment mechanism as the blue panel module and the red panel module 302. Therefore, when installing the green panel module, the position of the green panel module is not determined,
The panel module for blue color and the panel module for red color are properly fitted to the center part, and the panel module is used as a reference.

In the present embodiment, by employing the optical head alignment adjustment mechanism of the present invention, the alignment adjustment time can be reduced to about two-thirds as compared with the related art.

[Effects of the Invention] As described above, according to the present invention, in a liquid crystal projector, a configuration in which an alignment adjustment mechanism for a liquid crystal panel is provided for two liquid crystal panels, and the other liquid crystal panel is fixed. As a result, the number of alignment steps was reduced to about two-thirds. In addition, since the reference liquid crystal panel module can be fixed at the center position, it is possible to reduce troubles that the remaining blue panel module and red panel module cannot be adjusted in alignment adjustment. Therefore, there is an effect that the number of steps for adjusting the alignment of the liquid crystal panel is reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing an optical head of a three-panel liquid crystal video projector according to the present invention. 220 Fan fan 221 Base plate 222 Rear plate 223 Front plate 224 Projection lens 225 Upper plate 235 Dichroic prism 302 Panel module for green 303 Panel module for red 311 … Blue liquid crystal panel 312 …… Panel module fixing plate 313 …… Insulating sheet 314 …… Panel fixing plate 354 …… Panel module holding spring 420 …… Panel module fixing screw 421 …… Left-right adjustment screw 423 …… Depth of focus Adjusting screw 424... Vertical adjusting screw FIG. 2 is a diagram showing an optical head of a conventional three-panel liquid crystal video projector. 210: Rear plate 220: Fan housing 302: Green panel module 303: Red panel module 311: Blue liquid crystal panel 312: Panel module fixing plate 313: Insulating sheet 314: Panel fixing plate 354 ...... Panel module holding spring 421 ...... Horizontal adjustment screw 423 ...... Depth of focus adjustment screw 424 ...... Vertical adjustment screw FIG. 3 is a configuration diagram of a three-panel liquid crystal video projector. 101 light source lamp 301 blue separation dichroic mirror 302 green separation dichroic mirror 303 reflective mirror 304 reflective mirror 305 reflective mirror 306 dichroic prism 308 projection lens 309 Screen 311… LCD panel for blue 312… LCD panel for green 313… LCD panel for red

Claims (4)

(57) [Claims] 1. A liquid crystal panel for modulating three color lights, a combination optical unit for combining the color lights modulated by the three liquid crystal panels, and a projection optical unit for projecting the light combined by the combination optical unit. Means, wherein a first liquid crystal panel of the three liquid crystal panels is arranged at a fixed position with respect to the combining optical means, and a second and a third liquid crystal panel are provided with the first liquid crystal. A liquid crystal projector comprising a mechanism for adjusting an arrangement position with respect to a panel. 2. The liquid crystal projector according to claim 1, wherein said arrangement position adjusting mechanism includes means for adjusting a vertical direction, a horizontal direction, and a depth of focus direction. 3. The combining optical means comprises prisms having reflection surfaces having different reflection characteristics arranged in a cross shape, and the three liquid crystal panels are arranged on three surfaces of the prisms. The liquid crystal projector according to claim 1 or 2, wherein 4. The first liquid crystal panel is fixedly disposed on a surface of the three surfaces of the prism which is opposite to the surface on which the projection optical means is disposed, and is disposed on the remaining two surfaces. 4. The liquid crystal projector according to claim 3, wherein the second and third liquid crystal panels are provided with the adjustment mechanism.