JPH0463498A - Light source cooler for liquid crystal projector - Google Patents

Abstract

PURPOSE:To fire momentarily after deenergization by providing an air controller for feeding air at the time of energizing a light source to the inside of a recess of a cold mirror and preventing air flow at the time of deenergizing the light source, and inhibiting to cool the source during lighting, but cooling it during deenergizing. CONSTITUTION:Fins 8, 9 and a light source 1 are driven by different electrode switches. When the source 1 is energized, the fins 8, 9 are rotted to perform cooling. In this case, an electromagnet 14 is not operated, the holes 11A, 12A of shielding plates 11, 12 are not superposed, and hence a cold mirror 2, i.e., the source 1 is shut OFF from the fan 9, and not cooled. On the other hand, when the source 1 is deenergized, the electromagnet 14 is operated to slide the plate 12, the holes 11A and 12A coincide, and hence air flow occurs by the fan 9 around the source 1 to cool the source 1. Thus, the source is not cooled during energizing, but cooled during deenergizing, and hence it can be energized momentarily after deenergizing.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a liquid crystal projector that enlarges and projects liquid crystal panels using light from a light source, and in particular has a configuration that reduces the effect of heat from the light source on the panel. The present invention also relates to a light source cooling device for a liquid crystal projector that is capable of cooling only a portion of the light source when necessary.

2. Description of the Related Art Devices for enlarging and projecting a liquid crystal panel using a light source such as a metal halide have been commercially available and are generally called liquid crystal projectors. This is driven at high voltage to increase the brightness of the light source, but at the same time it emits a significant amount of infrared light. As a result, the temperature inside the center, especially near the light source, becomes quite high. Therefore, since liquid crystal panel related parts are easily affected by temperature and it is necessary to have a cooling structure, a method of cooling the inside of the panel using a fan is generally used. In order to make it portable and to save energy, there are many cases where the light source is turned off and then turned on again, in which case only the fan rotates.

Problems to be Solved by the Invention However, in general, once the light emitting tube of the light source block has been turned off, it cannot be turned on for several minutes until the light source part falls below a certain temperature, which is not practical. In addition, since performance would not be achieved if the light source was cooled while the light source was lit, a structure was required that would not cool the light source while the light source was lit.

SUMMARY OF THE INVENTION In view of the above, an object of the present invention is to provide a light source cooling device for a liquid crystal projector having a structure that cools only the arc tube portion of the light source when the light source is turned off.

Means for Solving the Problems In order to solve the above-mentioned problem i, a light source cooling device for a liquid crystal projector according to the present invention includes a light source, a concave mirror-like cold mirror that separates visible light and infrared light from the light source, a liquid crystal group that controls transmission of light from the light source; an optical system that enlarges or reduces an image formed by the liquid crystal group using the light from the light source;
an optical support member that holds the liquid crystal group and the optical system;
a box-shaped light source box that holds the light source and the cold mirror; a plurality of wind guide members that guide wind from the blower into the liquid crystal group and the light source box; The device includes a pressure control device that blows air when the light source is on and blocks the air when the light source is off.

The pressure control device is composed of an opening/closing member that opens to blow air when the light source is turned on and closes to block the wind when the light source is turned off, and a solenoid that drives the opening/closing member.

According to the present invention, a blowing means, a plurality of wind guide members for guiding the wind from the blowing means into the liquid crystal group and the light source box;
By providing a pressure control device on the inside of the concave surface of the cold mirror that sends wind when the light source is on and blocks the wind when the light source is off, the light source is not cooled when the light source is on and is cooled when it is off. It can be turned on instantly after turning off.

In addition, the pressure control device consists of an opening/closing member that blows air when the light source is on and closes to block the wind when the light source is off, and a solenoid that drives the opening/closing member. It can be changed to a configuration that sends air to the air, and the number of parts can be reduced.

Embodiment FIG. 1 shows a liquid crystal projector according to an embodiment of the present invention.
2 is a front view showing the entire light source cooling device, FIG. 2 is a side view thereof, and FIG. 3 is a plan view thereof.

In FIGS. 1 to 3, 1 is a light source, 2 is a cold mirror that separates infrared light and visible light, and 3 is a light source box that holds these. Further, the optical support member 4A4B that holds the panel, dichroic mirror, etc. is configured to partially sandwich the light source box 3, and is connected to the light source box 3 through an air layer by an integrally provided connecting member 5. There is. The set main body 7 is equipped with a fan A8, which is a blower (exhaust) means for discharging heat to the outside, and a fan B9, which is a suction fan. In addition, guide members 10 are stretched around various places to guide the air sucked from the fan B9 to various parts. On the other hand, the shielding plate All and the shielding plate B12 are each slidably attached by a guide 13 provided on the optical support member 4B. Hole 1 is provided in each of shielding plate All and shielding plate B12.
There are holes 1A and 11B. In addition, a magnet 14 is attached to one end of one of the shielding plates B12, and when this magnet 14 is activated (when the light source is turned off), the holes 11A and 12A are
The shielding plate B12 moves so that they overlap.

In this configuration, the fan 8.9 and the light source 1 are each driven by different power switches (not shown). When the light source 1 is turned on, the fan 8.9 also rotates and performs a cooling effect. At this time, the electromagnet 14 does not work, and the holes 11A and 12A of the shielding plate 11 and the shielding plate 12 do not overlap, so that the cold mirror 2 In other words, the light source 1 is cut off from the fan 9 and is not cooled.

On the other hand, if you turn off light source 1! The magnet 14 is activated, the shielding plate 12 slides, and the holes 11A and 12A are aligned.

Therefore, air flow is generated around the light source 1 by the fan 9, and the light source 1 is cooled.

As described above, according to the light source cooling device for a liquid crystal projector of this embodiment, the fan 9 sends air to the inside of the concave surface of the cold mirror 2 when the light source is on, and blocks the air when the light source is off.
Since the guide member 10 and the shielding plate IL 12 are equipped with a wind control device consisting of a magnet 14, the light source 1 is not cooled while the light is on, and is cooled while the light is off, so that it can be turned on instantly after the light is turned off. In addition, the wind control device includes an opening/closing member consisting of two shielding plates that opens to send air when the light source is on and closes to block the wind when the light source is off, and a solenoid that drives the opening/closing member. It is possible to change the configuration to blow air to the light source when necessary, even when the light is off.

In addition, in FIG. 1, color separation is performed by dividing the white light emitted from the light source 1 into red, blue, and
decomposed into green and collected by lenses 17a to 17c,
It passes through each of the liquid crystal panels 18a to 18c. The liquid crystal panels 18a to 18c are each fixed to a metal fitting. The same goes for color composition, and the guichroic mirrors 19a to 1
9c Red, blue, and green are combined into white light.

Effects of the Invention As described above, the present invention includes a light source, a concave cold mirror that separates visible light and infrared light from the light source, a liquid crystal group that controls transmission of light from the light source, and a liquid crystal group that controls transmission of light from the light source. an optical system that enlarges or reduces an image formed by the liquid crystal group using light from a light source; an optical support member that holds the liquid crystal group and the optical system; a box-shaped light source box that holds the light source and the cold mirror; A plurality of wind guide members for guiding wind into the liquid crystal group and the light source box are provided, and a wind control device is provided inside the concave surface of the cold mirror to send wind when the light source is turned on and to block the wind when the light source is turned off. As a result, the light source can be turned on instantly after being turned off by not cooling the light source while it is turned on and cooling it while it is turned off. In addition, the wind control device consists of an opening/closing member that blows air when the light source is on and closes to block the wind when the light source is off, and a solenoid that drives the opening/closing member. The configuration can be changed to send air to the light source, and its practical effects are great.

[Brief explanation of drawings]

FIG. 1 shows a liquid crystal projector according to an embodiment of the present invention.
FIG. 2 is a side view of FIG. 1, and FIG. 3 is a plan view of the light source cooling device. 1...Light source, 2...Cold mirror,
3...Light source box, 8...Fan A, 9.
...Fan B, 10...Guiding member, 11
・・・・・・Shielding plate A, 12 ・・・・・・Shielding plate B, 1
4... Electromagnet. Name of agent Patent attorney Shigetaka Awano Hikaru Mitsuyoshi Tomi 5-ssi Fan Tominai W material

Claims (2)

[Claims] (1) A light source, a concave cold mirror that separates visible light and infrared light from the light source, a liquid crystal group that controls transmission of light from the light source, and an image formed by the liquid crystal group using the light from the light source. an optical system for enlarging/reducing the liquid crystal group, an optical support member for holding the liquid crystal group and the optical system, a box-shaped light source box for holding the light source and the cold mirror, a ventilation means, and the liquid crystal group and the light source. The box includes a plurality of wind guide members for guiding the wind from the air blowing means, and a wind control device that sends wind to the inside of the concave surface of the cold mirror when the light source is turned on and blocks the wind when the light source is turned off. Light source cooling device for LCD projector. (2) The wind control device opens to blow air when the light source is turned on.
A light source cooling device for a liquid crystal projector comprising an opening/closing member that closes to block wind when the light source is turned off, and a solenoid that drives the opening/closing member.