JPH04267232A - Liquid crystal projector - Google Patents

Abstract

PURPOSE:To make cooling effects to three liquid crystal display sections, substantially uniform. CONSTITUTION:Each of three liquid crystal display sections is composed of a liquid crystal display panel and polarizers spaced from each other on both sides of the liquid crystal display panel so as to define air passages 21d, 26d, 23d between the polarizers and the liquid crystal panel in these three sections. The spaces of the flow passages 21d, 26d, 23d are successively wider from an intake port 36 to an exhaust port 34, and accordingly, the flow rate of air per unit time is less in the air passage 21d of the red light liquid crystal display section 21 on the intake port 36 side than in the air passage 26d of the green light liquid display section 26 in the intermediate section while the flow rate of air is larger in the air passage 23d of the blue light liquid display section 21 on the exhaust port 34 side than in the air passage 26d.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal projector.

0002

[Prior Art] A liquid crystal projector uses three components of light from a single light source: an R (red) component, a G (green) component, and a B (blue) component.
The light is dispersed into two lights and irradiated to the corresponding transmissive liquid crystal display, and each color image of a television etc., which is separated into three colors of R, G, and B and displayed on each liquid crystal display, is superimposed on the screen. There is a system in which the light source, liquid crystal display, etc. are air-cooled at the same time as the image is enlarged and projected.

FIG. 5 shows a schematic configuration of an example of such a conventional liquid crystal projector. This liquid crystal projector includes a rectangular main body case 1. The inside of the main body case 1 is separated into a light source chamber 3 and a liquid crystal display chamber 4 by a transparent partition plate 2 made of a glass plate or the like. The partition plate 2 includes a first partition part 2a that is perpendicular to one long side of the main body case 1, and a first partition part 2a that extends in a direction parallel to the long side of the main body case 1 from one end of the first partition plate part 2a. The third partition plate part 2c extends from one end of the second partition plate part 2b in a direction perpendicular to the other long side of the main body case 1. On one long side of the main body case 1 of the light source chamber 3, a first reflecting mirror 11 is arranged from the left side toward the right side.
, a first dichroic mirror 12 and a second dichroic mirror 13 are provided in this order. A light source 14 and its power source 15 are provided on the left side of the other long side of the main body case 1 of the light source chamber 3, and a second reflecting mirror 16 is provided on the right side. Main body case 1 of LCD display chamber 4
An R liquid crystal display section 21 is provided on the left side of one long side, and a third reflecting mirror 22 is provided on the right side. On the other long side of the main body case 1 of the liquid crystal display chamber 4, a B liquid crystal display section 23, a third dichroic mirror 24, and a fourth dichroic mirror 25 are provided in this order from the left side to the right side. ing. 3rd part of liquid crystal display chamber 4
A G liquid crystal display section 26 is provided near the partition plate section 2c. A projection lens 2 is provided at a predetermined location corresponding to the fourth dichroic mirror 25 on the other long side of the main body case 1.
7 is provided. Note that the R liquid crystal display section 21 is
The G liquid crystal display part 26 is arranged along the second partition part 2b, and the B liquid crystal display part 26 is arranged along the second partition part 2b.
3 is arranged along the third partition plate portion 2c. An exhaust port 31 is provided at a predetermined location corresponding to the light source 14 on the left short side of the main body case 1, and a first cooling fan 32 is provided inside the exhaust port 31. Main case 1
There is an air intake port 33 at a predetermined location corresponding to the power supply 15 on the bottom of the
is provided. An exhaust port 34 is provided at a predetermined location corresponding to the B liquid crystal display section 23 on the other long side of the main body case 1, and a second cooling fan 35 is provided inside this exhaust port 34. . R of one long side of main body case 1
An air intake port 36 is provided at a predetermined location corresponding to the liquid crystal display section 21 for use.
is provided.

[0004] Of the light from the light source 14 , the R component light is reflected by the first reflecting mirror 11 , and then reflected by the first dichroic mirror 12 and the second dichroic mirror 13 .
, passes through the first partition part 2 a and the R liquid crystal display part 21 , is reflected by the third reflection mirror 22 , passes through the fourth dichroic mirror 12 , and enters the projection lens 27 . The G component light is reflected by the first reflecting mirror 11, the first dichroic mirror 4, and the second reflecting mirror 16, and is reflected by the third partition part 2c, the G liquid crystal display part 23, and the third
The light passes through the fourth dichroic mirror 24 , is reflected by the fourth dichroic mirror 12 , and enters the projection lens 27 . The B component light is reflected by the first reflecting mirror 11, transmitted through the first dichroic mirror 12, reflected by the second dichroic mirror 13, and then passed through the second partition plate portion 2b.
and the B liquid crystal display section 26, the third dichroic mirror 24 and the fourth dichroic mirror 25.
, and enters the projection lens 27 . Light of each component of R, G, and B incident on the projection lens 27, that is, each color of television etc. separated into three colors of R, G, and B and displayed on each liquid crystal display section 21, 26, 23 Each light image corresponding to the image is superimposed and enlarged and projected onto a screen (not shown) by the projection lens 27. On the other hand, when the first cooling fan 32 is driven, as shown by arrow A in FIG. After being cooled, it is discharged to the outside from the exhaust port 31. When the second cooling fan 35 is driven, the air sucked into the liquid crystal display chamber 4 from the air intake port 36 flows along the first to third partition plates 2a to 2c, as shown by arrow B in FIG. After passing through the vicinity of the R liquid crystal display section 21, the G liquid crystal display section 26, and the B liquid crystal display section 23 in this order and sequentially cooling them, the liquid is discharged to the outside from the exhaust port 34.

[0005]

[Problems to be Solved by the Invention] However, in such a conventional liquid crystal projector, each liquid crystal display section 21,
26, 23 gradually increases from the intake port 36 side toward the exhaust port 34 side, whereas the three liquid crystal display sections 21, 26, 23 basically have the same structure. Since the liquid crystal display portions 21, 26, and 23 are simply cooled by air passing successively in the vicinity of each of them, the cooling effect on each liquid crystal display portion 21, 26, and 23 is different, and compared to the intermediate B liquid crystal display portion 26, The cooling effect on the R liquid crystal display section 21 on the intake port 36 side is large, and the cooling effect on the B liquid crystal display section 21 on the exhaust port 34 side is small.
Furthermore, there is a problem in that variations occur in the liquid crystal characteristics of each liquid crystal display section 21, 26, and 23, which may adversely affect image quality. An object of the present invention is to provide a liquid crystal projector that can provide substantially the same cooling effect on three liquid crystal display sections.

[0006]

[Means for Solving the Problems] The present invention consists of three liquid crystal display sections consisting of a liquid crystal display panel and an air guide member disposed near the liquid crystal display panel, and the liquid crystal display panel and the air guide member are arranged in the vicinity of the liquid crystal display panel. An air flow path is formed in between, and the flow rate of the air flow path gradually increases from upstream to downstream. Note that the liquid crystal display panel refers to a structure in which liquid crystal is sealed between at least two transparent substrates each having a transparent electrode on the inner surface.

[0007]

[Operation] According to the present invention, the flow rate of the air channels formed between the liquid crystal display panels of the three liquid crystal display units and the air guide members gradually increases as the flow moves from upstream to downstream. Therefore, compared to the middle LCD panel, the flow rate per unit time through the air flow path of the upstream liquid crystal display section is smaller, while the flow rate per unit time through the air flow path of the downstream side liquid crystal display section is smaller. Even if the temperature of the air used to cool each liquid crystal display panel gradually increases from upstream to downstream, it is possible to maintain approximately the same cooling effect on each liquid crystal display panel. can.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a schematic configuration of a liquid crystal projector according to an embodiment of this invention. In this figure, parts with the same names as those in FIG. 5 are given the same reference numerals, and their explanations will be omitted as appropriate.

In this liquid crystal projector, the configurations of the three liquid crystal display sections 21, 26, and 23 are slightly different. That is, as shown in FIG. 2, in the R liquid crystal display section 21, a liquid crystal display panel 21b is provided in the center of a shield case 21a, and polarizing plates (air guide members) 21c are provided on both sides of the shield case 21a. An air flow path 21d is formed between the portion where the liquid crystal display panel 21b is provided and the polarizing plate 21c, and the space between the air flow paths 21d is set to be X. As shown in FIG. 3, the G liquid crystal display section 26 includes a liquid crystal display panel 26 in the center of the shield case 26a.
b is provided, and polarizing plates (
An air flow path 26d is provided between the portion where the liquid crystal display panel 26b is provided and the polarizing plate 26c.
is formed, and the interval between the air flow paths 26d is Y. As shown in FIG. 4, the B liquid crystal display section 23 includes a liquid crystal display panel 23b provided in the center of a shield case 23a, and polarizing plates (air guide members) 23c provided on both sides of the shield case 23a. Panel 23
An air flow path 2 is provided between the portion where b is provided and the polarizing plate 23c.
3d are formed, and the interval between the air flow paths 23d is Z. Each interval X, Y, Z is X<Y<Z
The relationship becomes larger gradually from the intake port 36 side toward the exhaust port 34 side.

In this liquid crystal projector, when the second cooling fan 35 is driven, the air sucked into the liquid crystal display chamber 4 from the air intake port 36 flows into the first to third cooling fans as shown by arrow B in FIG. It flows along the partition plates 2a to 2c, passes near the R liquid crystal display part 21, the G liquid crystal display part 26, and the B liquid crystal display part 23 in this order, and then is discharged to the outside from the exhaust port 34. Ru. At this time, the three liquid crystal display sections 21
, 26, 23, the intervals X, Y, and Z between the air flow paths 21d, 26d, and 23d gradually increase from the intake port 36 side to the exhaust port 34 side, so that the intermediate G liquid crystal display section 26 Compared to the air intake port 36 side, the interval X between the air flow paths 21d of the R liquid crystal display section 21 is smaller, and the flow rate of air per unit time flowing through this air flow path 21d is smaller. The interval Z between the air channels 23d of the side liquid crystal display section 23 is large, and the flow rate of air per unit time flowing through the air channels 23d is large. For this reason,
Even if the temperature of the air for cooling each liquid crystal display section 21, 26, 23 gradually increases from the intake port 36 side to the exhaust port 34 side, each liquid crystal display section 21, 26, 23
The cooling effect for both can be made almost the same.

[0011] Note that the wind guiding member is not a polarizing plate, but
A dedicated wind guide member may also be used. In addition, when the partition plate 2 is composed of a transparent partition main body made of a glass plate or the like and a heat insulating plate made of a synthetic resin such as styrene foam provided around the partition main body, the liquid crystal display chamber 4 may be The room temperature can be made less susceptible to the influence of the room temperature of the light source chamber 3, and as a result, the room temperature of the liquid crystal display chamber 4 can be easily managed, and the temperature of each liquid crystal display section 21, 26, 23 can also be easily managed.

0012

As explained above, according to the present invention, the flow rate of the air channels formed between the liquid crystal display panels and the air guide members of the three liquid crystal display sections can be changed from upstream to downstream. Since the flow rate is gradually increased towards the end, the flow rate per unit time through the air flow path of the upstream liquid crystal display part becomes smaller compared to the intermediate liquid crystal display part, while the flow rate of the downstream liquid crystal display part becomes smaller. Even if the flow rate per unit time through the air flow path increases, and therefore the temperature of the air used to cool each liquid crystal display gradually increases from upstream to downstream, the cooling of each liquid crystal display remains The effects can be made almost the same, and in turn, it is possible to make it difficult for variations in the liquid crystal characteristics of each liquid crystal display panel to occur, and it is possible to improve the image quality.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a liquid crystal projector according to an embodiment of the invention.

FIG. 2 is a schematic configuration diagram of an R liquid crystal display section in this liquid crystal projector.

FIG. 3 is a schematic configuration diagram of a G liquid crystal display section in this liquid crystal projector.

FIG. 4 is a schematic configuration diagram of a B liquid crystal display section in this liquid crystal projector.

FIG. 5 is a schematic configuration diagram of an example of a conventional liquid crystal projector.

[Explanation of symbols]

1 Main body case 2 Partition plate 3. Light source room 4 Liquid crystal display room 21 Liquid crystal display for R 21d Air flow path 23 Liquid crystal display section for B 23d Air flow path 26 Liquid crystal display for G 26d Air flow path 34 Exhaust port 35 Second cooling fan 36 Intake port

Claims (2)

[Claims] [Claim 1] Three liquid crystal display sections are arranged, and a cooling fan is driven to cause air to flow sequentially along each of the liquid crystal display sections, and the three liquid crystal display sections are sequentially cooled by this flowing air. In the liquid crystal projector, each of the three liquid crystal display sections includes a liquid crystal display panel and an air guide member disposed near the liquid crystal display panel, and an air flow path is provided between the liquid crystal display panel and the air guide member. 1. A liquid crystal projector characterized in that the flow rate of the air flow path gradually increases from upstream to downstream. 2. The three liquid crystal display sections each include a liquid crystal display panel and an air guiding member made of a polarizing plate disposed near the liquid crystal display panel, and each of the three liquid crystal display sections includes a liquid crystal display panel and a wind guide member made of a polarizing plate disposed near the liquid crystal display panel, and a space between the liquid crystal display panel and the polarizing plate. An air flow path is formed, and the distance between the liquid crystal display panel and the polarizing plate in the air flow path gradually increases from upstream to downstream of the flow. LCD projector in the first range.