JPH05951Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a liquid crystal projector that projects an enlarged image displayed on the liquid crystal display panel onto a screen by irradiating the liquid crystal display panel with light from a light source lamp.

[Prior Art] The above-mentioned liquid crystal projector has the ability to damage the liquid crystal material in the liquid crystal display panel from the infrared components contained in the illumination light from the light source lamp and from heating due to temperature rise inside the projector (due to heat emitted by the light source lamp, etc.). It is equipped with an LCD cooler for protection. This liquid crystal cooler has the function of absorbing heat from the liquid crystal display panel whose temperature increases due to heating, so that the heat-sensitive liquid crystal material in the liquid crystal display panel is not affected by heat such as the above-mentioned infrared components. The liquid crystal display panel is designed to operate normally even if the liquid crystal projector is used for a long time.

Conventionally, such a liquid crystal cooler has a closed cooling container 1 containing a transparent liquid refrigerant such as an aqueous ethylene glycol solution, as shown in FIG.
A liquid crystal display panel 101 is attached to one side of 00 so as to be overlapped, and a heat pipe 102 is attached to the top.
is installed, and when the liquid crystal display panel 101 is heated by infrared components contained in the illumination light from the light source lamp and rises in temperature, the liquid refrigerant absorbs the heat, and the liquid refrigerant thus heated up. A heat pipe 102 is connected between the air and the outside air flowing inside the projector.
performs heat exchange to cool the liquid crystal display panel 101 so that the liquid crystal material is not affected by heat.

The heat pipe 102 is installed in a position that does not affect the liquid crystal display section of the liquid crystal display panel 101 on the upper part of the cooling container 100 so as to pass through both side walls, and both side parts 103 and 104 protrude to the outside by a predetermined length. A large number of heat dissipation fins 10 are provided on both sides 103 and 104 protruding to the outside.
5 is provided as a heat radiating part, and a central part 106 shown by a broken line located inside the cooling container 100 is used as a heat absorbing part. A working fluid such as fluorocarbon is contained in the central part 106 which is the heat absorbing part, and this working fluid absorbs heat from the heated liquid refrigerant in the cooling container 100. Due to this heat absorption, the working fluid in a condensed state is evaporated and vaporized into both side parts 103 and 104 which are heat dissipation parts.
to dissipate heat. After heat dissipation, the working fluid is condensed and liquefied and returned to the central portion 106 again.

[Problems] However, in the conventional liquid crystal cooler described above, in which the heat pipe 102 is used as a heat exchange means between the liquid refrigerant and the outside air, there is a problem in that the heat pipe 102 is expensive, resulting in high cost. .

[Purpose of the invention] This invention was made in view of the above-mentioned circumstances, and its purpose is to create a liquid crystal cooler that can inexpensively constitute a heat exchange means between the liquid refrigerant and the outside air. The purpose of the present invention is to provide a liquid crystal projector with the following features.

[Summary of the invention] In order to achieve the above object, this invention provides a liquid crystal projector that projects a display image of the liquid crystal display panel onto a screen by irradiating the liquid crystal display panel with light from a light source. A transparent cooling medium that is vaporized by heat is sealed in a container having transparent parts with a larger area than a display area on both sides, and the cooling medium that has absorbed heat in the container and is vaporized is liquefied again and flows out of the container. The present invention is characterized in that a cooler having a vaporized refrigerant storage chamber for dissipating heat is provided, and the liquid crystal display panel is disposed on one surface of the cooler in correspondence with the transparent portion.

[Example] An example of this invention will be described below with reference to FIGS. 1 and 2.

The liquid crystal cooler 1 has a liquid crystal display panel 4 attached to one side (front side) of a closed type cooling container 3 containing a liquid refrigerant 2 such as fluorocarbons that boils at a low temperature, and a liquid refrigerant 2 and the liquid refrigerant 2 on the top. The projector is configured to include a vaporized refrigerant storage chamber 5 serving as a heat exchange means with the outside air flowing inside the projector.

The cooling container 3 has a larger external shape than the liquid crystal display panel 4 and has openings at its front and rear surfaces, and these openings 6 and 7 are covered with transparent plates 8 and 9 made of glass or the like.
It is constituted by a vertical frame 10 closed by. Such a frame 10 is a molded product made of aluminum or the like having high thermal conductivity, and its top wall 11
The vaporized refrigerant accommodating chamber 5 is integrally formed in the central part of the housing during molding. This vaporized refrigerant storage chamber 5 has a cylindrical shape that communicates with the inside of the container and projects vertically upward,
Moreover, the head is hemispherical and has a structure in which a large number of plate-shaped heat dissipation fins 12 are provided on the outer peripheral surface.

The liquid crystal display panel 4 is a transmissive dot matrix liquid crystal panel that displays, for example, a television image, and includes a liquid crystal cell 13 in the center, polarizing plates 14 and 15 stacked on top of each other, and outer surfaces of these. Glass substrates 16 and 17 superimposed on
The glass substrate 17 on the back side is superimposed on the outer surface of the transparent plate 9 on the front side of the frame 10 and fixed by adhesive.

Liquid crystal cooler 1 of the embodiment having such a configuration
In this case, when the liquid crystal display panel 4 is heated by infrared components contained in the illumination light from the light source lamp and rises in temperature, the liquid refrigerant 2 in the cooling container 3 absorbs the heat. The temperature of the liquid refrigerant 2 rises due to this heat absorption, and when it reaches the boiling point, it evaporates and vaporizes, rises inside the cooling container 3, flows into the vaporized refrigerant storage chamber 5, and is contained therein, where it radiates heat to the outside, that is, the outside air flowing inside the projector. Heat is exchanged between the liquid and the liquid, which liquefies the liquid and drips into the container again. The liquid crystal display panel 4 is cooled by this action, and the liquid crystal cell 13 is cooled.
The liquid crystal material inside is not affected by heat. In this case, the liquid crystal display panel 4 is always kept at the same temperature as the boiling point of the liquid refrigerant 2.

Next, an outline of a liquid crystal projector equipped with the liquid crystal cooler 1 will be explained based on FIG.

This liquid crystal projector has a projection lens 19 on the front of a box-shaped projector main body 18,
Inside, from the front, a condensing Fresnel lens 20, a liquid crystal display panel 4, a liquid crystal cooler 1, a transparent plate 21, and a light source device 22 are provided in order, respectively, and a blower fan 23 is provided in the center of the upper part.

The projection lens 19 is for projecting the display image of the liquid crystal display panel 4 onto a screen surface (not shown), and is provided in a lens barrel 25 that is screwed into a barrel 24 that is fixed through the front surface of the projector main body 18. By turning the lens barrel 25, the light can be focused and adjusted according to the position of the screen on which the projected image is formed.

A condensing Fresnel lens 20 placed behind the projection lens 19 is used to condense the displayed image of the liquid crystal display panel 4 onto the projection lens 19, and is provided over the entire surface of a transparent plate made of acrylic resin or the like. It is a circular Fresnel lens in which a large number of annular convex lens parts are formed concentrically, and a plate-shaped holding frame 2 is provided vertically within the projector body 18.
It is held at 6.

The liquid crystal display panel 4 disposed behind the condensing Fresnel lens 20 is configured as described above, and when the cooling container 3 of the liquid crystal cooler 1 disposed at the rear is fixed inside the projector main body 18, the front side of the liquid crystal display panel 4 is It is located in

A transparent plate 21 placed behind the liquid crystal cooler 1 is for absorbing infrared components contained in the illumination light from the light source device 22, and is made of an infrared absorbing filter or heat-resistant glass, and is used to protect the projector body. The holding frame 27 is fixed to an opening 28 formed in the center of a plate-shaped holding frame 27 vertically installed in the holding frame 18 so as to close the opening 28 .

A light source device 22 arranged behind the transparent plate 21
consists of a discharge lamp 29 as a light source lamp, and a reflector 30 located behind the discharge lamp 29 that reflects the light emitted by the discharge lamp 29 forward as parallel light. It is installed in the projector main body 18 by being fitted and supported by a cylindrical holding frame 31 fixed to the projector body 18 . In this case, a xenon lamp is used as the discharge lamp 29, and the base 32 of this xenon lamp is connected to the reflector 3.
0 is inserted into the support hole 33 at the center.

A blower fan 23 disposed at the center of the upper part of the projector body 18 is used to circulate outside air A into the projector body 18, and a shroud 34 provided at the upper center of the projector body 18
The outside air A is rotatably installed inside the projector body 18, and by its rotational drive, the outside air A is drawn from the slit-shaped intake holes 35 and 36 formed on the front and rear surfaces of the projector main body 18.
is taken in, flows inside the projector body 18 as shown by the arrow, and is discharged to the outside from a slit-shaped exhaust hole 37 formed at the upper center of the projector body 18. In this way, while the outside air A flows inside the projector body 18, the outside air A air-cools each component such as the light source device 22 inside the projector body 18, and also cools the liquid refrigerant 2 in the vaporized refrigerant storage chamber 5 of the liquid crystal cooler 1. The liquid crystal display panel 4 is cooled by exchanging heat with the liquid crystal display panel 4.

In the liquid crystal projector configured in this way, when the discharge lamp 29 of the light source device 22 is turned on and a television image or the like is displayed on the liquid crystal display panel 4,
As shown, the illumination light from the discharge lamp 29 reflected by the reflector 30 is directed toward the liquid crystal display panel 4 in parallel to an optical axis O connecting the center of the liquid crystal display panel 4 and the center of a screen (not shown). The illumination light from the discharge lamp 29 reflected by the reflector 30 first passes through the transparent plate 21 and has its infrared component absorbed, and then passes through the liquid crystal cooler 1 to affect the liquid crystal display panel 4. Light from the back side. The light that has passed through the liquid crystal display panel 4, that is, the light image corresponding to the display image on the liquid crystal display panel 4, is focused by the condensing Fresnel lens 20 onto the projection lens 19, and is magnified by the projection lens 19 to be displayed on the screen. projected onto a surface.

In addition, in this invention, the vaporized refrigerant storage chamber provided in the upper part of the cooling container is integrally formed with the cooling container in the embodiment, but it may be constructed separately from the cooling container and attached to the cooling container. Good too. In such a case, only the vaporized refrigerant storage chamber can be made of a material with high thermal conductivity such as aluminum.

[Effects of the invention] As explained above, the liquid crystal projector of this invention is a liquid crystal projector that projects a display image of the liquid crystal display panel onto a screen by irradiating the liquid crystal display panel with light from a light source. A transparent cooling medium that is vaporized by heat is sealed in a container that has transparent parts on both sides having a larger area than the display area, and the cooling medium that has absorbed heat in the container and is vaporized is liquefied again and is released outside the container. A cooler is provided with a vaporized refrigerant storage chamber for dissipating heat, and the liquid crystal display panel is disposed on one side of the cooler in correspondence with the transparent part. It is possible to provide an inexpensive liquid crystal projector that can exchange heat with the outside.

[Brief explanation of drawings]

Figure 1 is a sectional view of a liquid crystal cooler according to an embodiment of this invention, Figure 2 is a front view of the same liquid crystal cooler, and Figure 3 is a front view of the same liquid crystal cooler.
The figure is a sectional view of a liquid crystal projector equipped with the same liquid crystal cooler, and FIG. 4 is a front view of a conventional liquid crystal cooler. 1... Liquid crystal cooler, 2... Liquid refrigerant, 3... Cooling container, 4... Liquid crystal display panel, 5... Vaporized refrigerant storage chamber, 18... Projector main body.

Claims (1)

[Scope of Claim for Utility Model Registration] In a liquid crystal projector that projects a display image of the liquid crystal display panel onto a screen by irradiating the liquid crystal display panel with light from a light source, a transparent portion having a larger area than the display area of the liquid crystal display panel is provided. A transparent cooling medium that is vaporized by heat is sealed in a container formed on both sides, and the container has a vaporized refrigerant storage chamber in which the cooling medium that absorbs heat and is vaporized is liquefied again and radiates heat outside the container. A liquid crystal projector characterized in that a cooler is provided, and the liquid crystal display panel is disposed on one surface of the cooler in correspondence with the transparent portion.