JPH10325982A - Liquid crystal projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal projector where influence from a heat source on a liquid crystal panel unit is eliminated and which displays stabilized information having high output. SOLUTION: A chassis 1 separating the liquid crystal projector into upper and lower parts is arranged at the nearly center part of the liquid crystal projector. A lens unit 2 and a LCD unit 3 are arranged on the front side of a projector upper part separated by the chassis 1, and a polarizing plate unit 4 is arranged so as to be separated from the LCD unit 3 on a rear side, and also a lamp unit 5 and an air blowing fan 6 are arranged on a further rear side. A power source block 7 that is a heat source is arranged at a prcojector lower part separated by the chassis 1. Then, heat generated from the power source block 7 is shielded by the chassis 1, so that the thermal influence of the projector lower part is not given to the projector upper part.

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 for enlarging and projecting information of a liquid crystal panel onto a screen by using light emitted from a light source, and more particularly, to reducing the influence of heat from a light source and a power supply on the liquid crystal panel. The present invention relates to a liquid crystal projector.

[0002]

2. Description of the Related Art Conventionally, in a liquid crystal projector (hereinafter, also simply referred to as "projector"), light transmitted from a liquid crystal panel is projected on a screen by light from a light source to display images and information. That is, a conventional liquid crystal projector forms illumination light with a light source such as a metal halide lamp, drives the respective liquid crystal panels with red, green, and blue color signals, and emits red light separated by a color separation unit. , Green, and blue light are transmitted through each liquid crystal panel. After the transmitted lights of these liquid crystal panels are combined by a light combining means, they are projected on the screen surface by a projection means to form a color projected image. The liquid crystal projector having such a configuration is called a three-panel front projector,
In addition, there are a single-panel type front projector that obtains a color image by using one color liquid crystal panel, and a rear projector that irradiates a mirror with irradiation light and irradiates the rear surface of the screen.

A light source lamp such as a metal halide lamp and a power supply block for lighting the lamp are heat sources.
As the light source lamp is turned on, the temperature inside the projector rises. In other words, the liquid crystal panel transmits light by irradiating the light of the light source lamp and enlarges the image through the projection lens, but the light from the light source lamp directly enters the liquid crystal panel. It absorbs the light energy and infrared light of the light source lamp and generates heat.

As is well known, liquid crystal panels are susceptible to high temperatures,
When the temperature rises, the contrast ratio may decrease, or in the worst case (approximately 80 ° C. or higher), the liquid crystal panel may boil and lose its function as a display device. For this reason, it is common practice to blow air to the liquid crystal panel with a blower fan to cool the liquid crystal panel with air.

[0005] Recently, market demands for liquid crystal projectors are high resolution, high output (high brightness) and miniaturization. Any of these requests raises the temperature inside the projector,
Eventually, the temperature of the LCD panel will increase,
A technique for efficiently cooling a liquid crystal panel is an important technique particularly when downsizing a liquid crystal projector. The present invention relates to a method for cooling a liquid crystal panel in a small-sized liquid crystal projector. In the following description, a single-panel type front projector will be described as an example of a liquid crystal projector.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to eliminate the influence of a heat source on a liquid crystal panel of a liquid crystal projector which has been miniaturized, thereby achieving a high output and stable operation. An object of the present invention is to provide a liquid crystal projector capable of displaying information.

[0007]

According to the present invention, there is provided a liquid crystal projector comprising: a light source; a liquid crystal panel unit including a polarizing plate and a liquid crystal panel for controlling transmission of light emitted from the light source; In a liquid crystal projector including a power supply unit for supplying power to the liquid crystal panel unit and an optical unit for enlarging and reducing an image formed by the liquid crystal panel unit, at least a liquid crystal panel unit is disposed at a substantially central portion in a vertical direction of the liquid crystal projector. And a chassis that separates the upper part of the projector from at least the lower part of the projector in which the power supply means is disposed. Then, the heat generated by the power supply means is cut off by the chassis, so that the thermal influence of the lower part of the projector does not reach the main parts such as the liquid crystal panel unit on the upper part of the projector. Thereby, the operation of the main components such as the liquid crystal panel unit can be stabilized.

In addition, on the back side of the liquid crystal projector of the present invention (facing the optical means when viewed from the front), a blower fan for discharging air inside the liquid crystal projector is provided, and the liquid crystal panel of the liquid crystal projector is provided. At a predetermined position corresponding to the unit, for example, it is preferable that an outside air intake port and an intake duct connected thereto are provided on a side wall corresponding to the liquid crystal panel unit position. Then, the air after cooling the main components by the outside air sucked from the outside air intake port is discharged to the outside of the liquid crystal project by the blower fan. As a result, the main components such as the liquid crystal panel unit are directly cooled by the outside air sucked from the outside air intake port and are not affected by the rise in the temperature inside the liquid crystal projector such as the power supply means, and the main components such as the image display unit are stabilized. Is achieved.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.

First, with reference to FIG. 1 and FIG. 2, the main configuration and operation of the liquid crystal projector of the present invention will be described. FIG. 1 is a side sectional view showing an example of the liquid crystal projector of the present invention, and FIG. 2 is a front sectional view taken along line AA of FIG.

A liquid crystal projector of the present invention as shown in FIG. 1 is entirely covered with a cover, and a chassis 1 forming a housing is arranged inside the cover so as to separate the upper and lower sides of the projector. The front shape of the chassis 1 is bent into a crank shape as shown in FIG. 2, and the flat portion and the side portion of the bent chassis 1 have LCDs.
(Liquid Crystal Display) The main components such as the unit 3 are attached. Thereby, the chassis 1 also contributes to downsizing of the entire liquid crystal projector.

A lens unit 2 and an LCD unit 3 are arranged on the upper front side of the liquid crystal projector of the present invention.
A polarizing plate unit 4 is disposed behind the LCD unit 3 and is separated from the LCD unit 3. The polarizing plate unit 4, the LCD unit 3, and an exit-side polarizing plate (not shown) of the LCD unit 3 constitute a liquid crystal panel unit. (Some liquid crystal panel units disperse liquid crystal molecules in a polymer and do not require a polarizing plate.) A lamp unit 5 and a blower fan 6 are arranged behind the liquid crystal panel unit.

Below the projector separated by the chassis 1, a power supply block 7 for mainly driving the light source lamp 5a is disposed. In the following description, the upper part and lower part of the chassis 1 will be defined as the lower part, the lens unit 2 side as the front side, and the blower fan 6 side as the rear side.
Further, details of a method of attaching each unit to the chassis 1 will be omitted.

A chassis 1 arranged at a substantially central portion of the liquid crystal projector has a role of separating an upper part of the projector where main parts are arranged and a lower part of the projector where a power supply block 7 as a heat source is arranged. Chassis 1
Of the power supply block 7 does not affect the main parts above the projector.

That is, the outside air sucked from the lower front side of the liquid crystal projector by the blower fan 6 disposed on the rear side of the projector is blocked by the chassis 1 from flowing to the upper part of the projector, and the front side of the power supply block 7 is blocked from the rear side. As a result, the power supply block 7 is cooled by air. Thus, the thermal effect of the power supply block 7 does not affect the LCD unit 3 and the like, and the temperature rise of the LCD unit 3 and the like is reduced.

The lamp unit 5 has a light source lamp 5a such as a metal halide lamp and a lamp reflector 5b integrally formed, and is held exchangeably by a holding mechanism (not shown). In the lamp reflector 5b, the optical path is bent so as to be substantially parallel to the optical path of the illumination light emitted from the light source lamp 5a, and the polarizing plate unit 4 and the LCD unit 3 are bent.
Is transmitted. The LCD unit 3 modulates the illumination light into image light and emits the light to the lens unit 2 as optical means. In the lens unit 2, the LCD
The image light modulated by the unit 3 is enlarged and irradiated to project a color image on a screen (not shown).

Similarly, details of a method for cooling the main components disposed above the projector will be described with reference to FIGS.

LCD in the liquid crystal projector of the present invention
In a portion where the unit 3 and the polarizing plate unit 4 are located (see FIG. 1), a blower fan 8 (not necessarily required) and an external air inlet 9 are arranged. Inside the external air inlet 9, the outside air sucked from the external air inlet 9 is supplied with a blower fan 8.
An intake duct 10 (see FIG. 1) is provided, and a second external intake port 11 is arranged in front of the intake duct 10.

Then, outside air is taken in from the outside air intake port 9 and the intake duct 10 by the blowing fans 6 and 8, and the taken outside air causes the space between the lens unit 2 and the LCD unit 3 and the space between the LCD unit 3 and the polarizing plate unit 4 (see FIG. 1) to force the air to cool the liquid crystal panel unit. As described above, in the liquid crystal projector of the present invention, the LCD unit 3 and the polarizing plate unit 4 are directly cooled by the outside air taken in from the outside air intake port 9 and the intake duct 10. In addition to reducing the rise, LC due to the rise in temperature inside the liquid crystal projector
The influence on the D unit 3 and the polarizing plate unit 4 can be reduced.

Here, the input plate 4a of the polarizing plate unit 4 is
As shown in the side sectional view of FIG.
The input plate 4a is provided with a ventilation hole 12 for passing outside air smoothly as shown in the front view of FIG. This allows
The outside air sucked from the outside air intake port 9 and the intake duct 10 can be passed through the rear side of the projector in order, and the heat generated from the lamp unit 5 can also be blown out to the rear of the projector.

Next, the operation of the second outside air intake port provided in the intake duct of the liquid crystal projector of the present invention will be described with reference to FIG.

While the liquid crystal projector of the present invention is air-cooled through the outside air intake port 9 and the intake duct 10, if the outside air intake port 9 is blocked for some reason, the inside of the projector is closed and the temperature inside the projector becomes lower. To rise.
When the temperature inside the projector rises, there is a possibility that the members constituting the liquid crystal projector may be altered or deformed.
Therefore, in the liquid crystal projector of the present invention, the second outside air intake port 11 is provided as shown in FIG.

If the outside air intake port 9 is closed, the air inside the liquid crystal projector is sucked by the second outside air intake port 11 to form a new air flow inside the projector. Safety considerations have been made. Thereby, the safety performance of the liquid crystal projector when the outside air intake port 9 is closed can be further improved. Although not shown, the second outside air intake port 11 is constituted by a lid that opens inward, and this lid is used to take advantage of the fact that the pressure inside the projector decreases when the outside air intake port 9 is closed. May be automatically opened.

The liquid crystal projector of the present invention has the following specific effects. First, the liquid crystal projector of the present invention connects the LCD unit 3 and the like to the outside air inlet 9.
In addition, since the air is directly cooled by the outside air taken in from the intake duct 10, the temperature rise of the LCD unit 3 and the like can be reduced, and the thermal influence on the LCD unit 3 and the like due to the temperature rise in the liquid crystal projector can be reduced. . Secondly, since the liquid crystal projector of the present invention can construct a cooling system by reducing the number of blower fans to one or two, it is advantageous for miniaturization of the liquid crystal projector. Third, since the chassis 1 is simply arranged at the center to realize the liquid crystal projector structure of the present invention, it is advantageous in reducing the size and cost of the entire liquid crystal projector. Fourth, the duct structure of the liquid crystal projector of the present invention can be easily realized only by providing the intake duct 10 in the chassis 1 or the like, which is advantageous in reducing the size and cost of the entire liquid crystal projector.

The present invention is not limited to the above embodiment,
Various embodiments can be employed. For example, a configuration in which a light source is arranged below the projector (light is radiated to an LCD unit or the like via a mirror) and a main component such as the LCD unit and a heat source such as a light source or a power supply may be completely separated may be adopted.
The present invention is applied to all projector devices having a structure in which the upper and lower portions of the projector are blocked by a chassis. Although the single-panel front projector has been described in the present embodiment, it is needless to say that the present invention can be widely applied to various three-panel front projectors, rear-projection-type liquid crystal projectors, and various projector apparatuses using an image display unit other than the LCD unit. it can.

[0026]

As described above, the liquid crystal projector of the present invention has a structure in which a chassis structure separates an upper part of the projector where main components such as a liquid crystal panel are arranged and a lower part of the projector where a power source as a heat source is arranged. And
For this reason, the thermal degradation of the main components such as the liquid crystal panel can be reduced without the thermal effects of the power supply and the like affecting the main components on the upper part of the projector. Also, in the liquid crystal projector of the present invention, since outside air is taken in directly from the blower fan and the intake duct to cool the main parts such as the liquid crystal panel, the temperature rise of the main parts is reduced, and the temperature inside the liquid crystal projector machine is raised. Therefore, the influence on the main parts due to is reduced, which is beneficial.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an example of a liquid crystal projector of the present invention.

FIG. 2 is a front sectional view taken along line AA of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... chassis, 2 ... lens unit, 3 ... LCD unit, 4 ... polarizing plate unit, 5 ... lamp unit, 6, 8
... fan for air blow, 7 ... power supply block, 9 ... outside air intake port,
10: intake duct, 11: second outside air intake port

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ichiro Sasaki 8-4 Shiomi, Kisarazu-shi, Chiba Sony Kisarazu Corporation

Claims (7)

[Claims] A light source; a liquid crystal panel unit that controls transmission of light emitted from the light source; a power supply unit that supplies power to the light source and the liquid crystal panel unit; and an image formed by the liquid crystal panel unit. A liquid crystal projector comprising: an optical unit, at a substantially central portion of the liquid crystal projector, an upper part of the projector in which at least the liquid crystal panel unit is arranged;
A liquid crystal projector, comprising a chassis for separating at least a lower part of the projector on which the power supply unit is disposed. 2. An air blower fan for discharging air from the inside of the liquid crystal projector is provided on a back surface of the liquid crystal projector, and a predetermined position of a portion corresponding to the liquid crystal panel unit of the liquid crystal projector is provided with outside air intake. mouth,
The liquid crystal projector according to claim 1, further comprising an intake duct connected to the outside air intake port. 3. A second outside air intake port, which forms a new air flow inside the liquid crystal projector when the outside air intake port is closed, is provided at a predetermined position of the intake duct. The liquid crystal projector according to claim 2, wherein: 4. A structure in which the second outside air intake port is configured to automatically open when the outside air intake port is closed by utilizing a decrease in pressure inside the liquid crystal projector. The liquid crystal projector according to claim 3, wherein: 5. An input plate for guiding outside air sucked from the outside air intake port to the liquid crystal panel unit is formed below the entrance side polarizing plate of the liquid crystal panel unit,
2. The liquid crystal projector according to claim 1, wherein a ventilation hole for regulating the flow of outside air is formed in the input plate. 6. The liquid crystal projector according to claim 1, wherein a front shape of the chassis is formed by being bent in a crank shape. 7. The light source, wherein the chassis includes at least the light source;
The liquid crystal projector according to claim 1, wherein the liquid crystal panel unit and the optical unit are also used as a locking unit.