JP3200769B2 - LCD projector - Google Patents

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]

2. Description of the Related Art In a liquid crystal projector, light from one light source is divided into R (red), G (green) and B (blue) components.
And irradiate them to the corresponding transmissive liquid crystal display units, and superimpose each color image of a television or the like displayed on each liquid crystal display unit in three colors of R, G and B. In some cases, the light source and the liquid crystal display unit are air-cooled.

FIG. 5 shows a schematic configuration of an example of such a conventional liquid crystal projector. This liquid crystal projector includes a main body case 1 having a rectangular shape. The inside of the main body case 1 is separated into a light source room 3 and a liquid crystal display room 4 by a transparent partition plate 2 made of a glass plate or the like. The partition 2 has a first partition 2 a orthogonal to one long side of the main body case 1, and a first partition 2 a extending from one end of the first partition 2 a in a direction parallel to the long side of the main body case 1. 2 partition 2b
And a third partition 2c extending from one end of the second partition 2b in a direction orthogonal 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 room 3, a first reflection mirror 1 is arranged from left to right.
1, a first dichroic mirror 12 and a second dichroic mirror 13 are provided in this order. A light source 14 is provided on the left side of the other long side of the main body case 1 of the light source chamber 3.
And a power supply 15 thereof, and a second reflection mirror 16 is provided on the right side. An R liquid crystal display section 21 is provided on the left side of the main case 1 of the liquid crystal display chamber 4 on one long side, and a third reflection mirror 22 is provided on the right side. On the other long side of the main body case 1 of the liquid crystal display room 4,
From the left side to the right side, a B liquid crystal display unit 23, a third dichroic mirror 24, and a fourth dichroic mirror 25 are provided in this order. A G liquid crystal display unit 26 is provided in the liquid crystal display chamber 4 near the third partition 2c. A projection lens 27 is provided at a predetermined position on the other long side of the main body case 1 corresponding to the fourth dichroic mirror 25. Note that the R liquid crystal display unit 21 is disposed along the first partition 2a, and the G liquid crystal display unit 2
Reference numeral 6 is disposed along the second partition 2b, and the liquid crystal display for B 23 is disposed along the third partition 2c. An exhaust port 31 is provided at a predetermined position corresponding to the light source 14 on the left side of the main body case 1, and a first cooling fan 32 is provided inside the exhaust port 31. An intake port 33 is provided at a predetermined location corresponding to the power supply 15 on the bottom surface of the main body case 1. B on the other long side of body case 1
An exhaust port 34 is provided at a predetermined location corresponding to the
A second cooling fan 35 is provided inside the exhaust port 34. An intake port 36 is provided at a predetermined location corresponding to the R liquid crystal display section 21 on one long side of the main body case 1.

[0004] Of the light from the light source 14, the R component light is reflected by the first reflecting mirror 11, and the first dichroic mirror 12 and the second dichroic mirror 1 are reflected.
3. The light passes through the first partition 2a and the R liquid crystal display 21, is reflected by the third reflection mirror 22, passes through the fourth dichroic mirror 12, and enters the projection lens 27. The light of the G component is reflected by the first reflecting mirror 11, the first dichroic mirror 4, and the second reflecting mirror 16, and the third partition 2c, the G liquid crystal display 23, and the third dichroic mirror. 24, is reflected by the fourth dichroic mirror 12, and enters the projection lens 27. The light of the B component is reflected by the first reflecting mirror 11, passes through the first dichroic mirror 12, is reflected by the second dichroic mirror 13, and passes through the second partition 2.
b and B, which are transmitted through the liquid crystal display unit 26 and the third dichroic mirror 24 and the fourth dichroic mirror 2.
The light is reflected by 5 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 a television or the like displayed in each of the liquid crystal display units 21, 26, and 23 after being separated into three colors of R, G, and B and displayed. Each light image corresponding to the image is superimposed on a screen (not shown) by the projection lens 27 and is enlarged and projected. On the other hand, when the first cooling fan 32 is driven, as shown by an arrow A in FIG. 5, air sucked into the light source chamber 3 from the intake port 33 passes through the vicinity of the power source 15 and the light source 14 and Is cooled and then discharged to the outside through the exhaust port 31. Second
When the cooling fan 35 of FIG.
As shown by the arrows, the air sucked into the liquid crystal display chamber 4 from the intake port 36 flows along the first to third partition portions 2a to 2c, and the R liquid crystal display portion 21 and the G liquid crystal display portion 26. And B
After passing through the vicinity of the liquid crystal display unit 23 in this order and cooling them sequentially, they are discharged from the exhaust port 34 to the outside.

[0005]

However, in such a conventional liquid crystal projector, each of the liquid crystal display units 21 and
While the temperature of the air for cooling the cooling air 26, 23 gradually increases from the intake port 36 toward the exhaust port 34, the three liquid crystal display sections 21, 26, 23 have basically the same structure. The cooling effect on the liquid crystal display units 21, 26, and 23 is different from that of the intermediate B liquid crystal display unit 26 because the air is merely cooled by the air that sequentially passes through the respective vicinity. The cooling effect on the R liquid crystal display unit 21 on the intake port 36 side is large, and the cooling effect on the B liquid crystal display unit 21 on the exhaust port 34 side is small.
As a result, there is a problem that the liquid crystal characteristics of the liquid crystal display units 21, 26, and 23 vary, which may adversely affect the image quality. An object of the present invention is to provide a liquid crystal projector that can make the cooling effect on a plurality of liquid crystal display units substantially the same.

[0006]

According to the present invention, a plurality of liquid crystal display units are constituted by a liquid crystal display panel and a baffle member arranged near the liquid crystal display panel. When an air flow path is formed between
In addition, the flow rate of the air flow path is
It becomes larger gradually from the air flow path toward the downstream .

[0007]

SUMMARY OF] According to the present invention, a plurality of the liquid crystal display unit of the liquid crystal display unit of the upstream of the flow rate of the air flow passage the flow of each liquid crystal display unit which are formed between the liquid crystal display panel and the air duct member
As it gradually increases as it goes downstream from the air flow path , compared to the middle liquid crystal display panel,
The flow rate per unit time flowing through the air flow path of the liquid crystal display unit on the upstream side decreases, while the flow rate per unit time flowing through the air flow path of the liquid crystal display unit on the downstream side increases. Even if the temperature of the air for cooling the liquid crystal display panel gradually increases from upstream to downstream of the flow, the cooling effect on each liquid crystal display panel can be made substantially the same.

[0008]

FIG. 1 shows a schematic configuration of a liquid crystal projector according to an embodiment of the present invention. In this figure, the same reference numerals are given to the same parts as those in FIG. 5, and the description thereof will be omitted as appropriate.

In this liquid crystal projector, the respective structures of the three liquid crystal display units 21, 26, and 23 are slightly different. That is, as shown in FIG. 2, the R liquid crystal display unit 21 has a liquid crystal display panel 21b provided at the center of a shield case 21a, and polarizing plates (wind guide members) 21c 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 interval between the air flow paths 21d is set to X. As shown in FIG. 3, the G liquid crystal display unit 26 has a liquid crystal display panel 2 at the center of the shield case 26a.
6b, a polarizing plate (wind guide member) 26c is provided on both sides of the shield case 26a, and the liquid crystal display panel 26b is provided.
Air passage 26 between the portion provided with
d is formed, and the interval between the air flow paths 26d is set to Y. As shown in FIG. 4, the liquid crystal display unit for B 23 has a liquid crystal display panel 23b provided at the center of a shield case 23a, and polarizing plates (wind guide members) 23c provided on both sides of the shield case 23a. Panel 2
An air flow path 23d is formed between the portion where 3b is provided and the polarizing plate 23c, and the air flow path 23d has a structure in which the distance between the air flow paths 23d is Z. Each interval X, Y, Z is represented by X <Y <
There is a relationship of Z, and it gradually increases from the intake port 36 side to 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 inlet 36 as shown by the arrow B in FIG. After flowing along the partition portions 2a to 2c and passing through the vicinity of the R liquid crystal display portion 21, the G liquid crystal display portion 26, and the B liquid crystal display portion 23 in this order, the air is discharged from the exhaust port 34 to the outside. You. At this time, three liquid crystal display units 2
Since the intervals X, Y, and Z of the air flow paths 21d, 26d, and 23d of 1, 26, and 23 gradually increase from the intake port 36 side to the exhaust port 34 side, an intermediate G liquid crystal display unit. 26, the interval X between the air flow paths 21d of the R liquid crystal display unit 21 on the intake port 36 side is smaller, and the flow rate of air per unit time flowing through the air flow path 21d is smaller. The space Z between the air flow paths 23d of the liquid crystal display unit 23 on the 34 side is large, and the flow rate of air per unit time flowing through the air flow paths 23d becomes large. For this reason, even if the temperature of the air for cooling the liquid crystal display units 21, 26, and 23 gradually increases from the intake port 36 side to the exhaust port 34 side, the liquid crystal display units 21, 26, 23
23 can have substantially the same cooling effect.

[0011] The wind guide member is not a polarizing plate, but
A dedicated air guide member may be used. When the partition 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 main body of the partition, the liquid crystal display chamber 4 The room temperature can be made hard to be affected by the room temperature of the light source room 3, so that the room temperature of the liquid crystal display room 4 can be easily managed, and the temperatures of the liquid crystal display units 21, 26, and 23 can be easily managed.

[0012]

As described above, according to the present invention, the flow rate of the air flow path for each liquid crystal display unit formed between the liquid crystal display panel and the air guide member is controlled by a plurality of liquid crystal display units. From the air flow path of the liquid crystal display upstream of the flow
, The flow rate per unit time flowing through the air flow path of the liquid crystal display on the upstream side is smaller than that on the middle liquid crystal display panel, while the liquid crystal display on the downstream side is smaller. Even if the temperature of the air for cooling each liquid crystal display section gradually increases from the upstream to the downstream of the flow, even if the temperature of the air for cooling each liquid crystal display section gradually increases, The cooling effect can be made substantially the same, so that the liquid crystal characteristics of each liquid crystal display panel can be made less likely to vary, and the image quality can be improved.

[Brief description of the drawings]

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

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

FIG. 3 is a schematic configuration diagram of a G liquid crystal display unit in the liquid crystal projector.

FIG. 4 is a schematic configuration diagram of a liquid crystal display unit for B in the liquid crystal projector.

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

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 body case 2 partition plate 3 light source room 4 liquid crystal display room 21 liquid crystal display portion for R 21 d air flow channel 23 B liquid crystal display portion 23 d air flow channel 26 G liquid crystal display portion 26 d air flow channel 34 exhaust port 35 second Cooling fan 36 Inlet

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification code FI G09F 9/00 304 G09F 9/00 304B 360 360K H05K 7/20 H05K 7/20 G

Claims (2)

(57) [Claims] 1. A liquid crystal in which a plurality of liquid crystal display portions are arranged, and air flows sequentially along each of the liquid crystal display portions by driving a cooling fan, and the flowing air cools the plurality of liquid crystal display portions. In the projector, the plurality of liquid crystal display units include a liquid crystal display panel and a baffle member disposed near the liquid crystal display panel, and an air flow path is formed between the liquid crystal display panel and the baffle member. And the flow rate of the air flow path is
From the air flow path of the liquid crystal display to the downstream
Liquid crystal projector characterized by being configured to gradually increase wishes. 2. The liquid crystal display section includes a liquid crystal display panel and a wind guide member formed of a polarizing plate disposed near the liquid crystal display panel. together with the air flow path is formed, the
The distance between the liquid crystal display panel and the polarizing plate of the liquid crystal display unit
From the air flow path of the liquid crystal display upstream of the flow
2. The liquid crystal projector according to claim 1, wherein the liquid crystal projector is configured to increase gradually as it goes .