JPH0460533A - Cooling control mechanism for liquid crystal projector - Google Patents

Abstract

PURPOSE:To perform control so that a projector can operate and to monitor the cause of abnormality by controlling the temperature of each liquid crystal panel with detection data detected by a detecting means. CONSTITUTION:Wind speed sensors 14 and temperature sensors 15 are arranged on the front surfaces of the liquid crystal panels 10R, 10G, and 10B and detect wind speeds and temperatures at the positions. when a wind speed is 0, a power source 19 is turned OFF so as to protect the liquid crystal panel 10. The temperatures are sent to comparing means 22, which send data to the system controller 21 of a microcomputer 17 when the detected ambient temperatures are lower then an operation upper-limit temperature (t). Further, when the detected ambient temperatures T are higher than the operation upper-limit temperature (t), the power source 19 is turned OFF so as to protects the liquid crystal panels 10. consequently, the rotating speeds of a cooling fan and an air discharging fan can be controlled corresponding to the ambient temperatures and the clogging of a filter can be monitored.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cooling control mechanism for a liquid crystal projector that functions to suppress a rise in temperature of a liquid crystal panel in response to a rise in ambient temperature.

[Prior Art] A liquid crystal projector P', for example, as shown in FIG. a reflective mirror 6°7, a dichroic mirror 8.9 for color synthesis, and a liquid crystal panel I for the three primary colors R, G, and B.
It is composed of an OR, an IOC, 10B, and a projection lens 11.

Then, the light emitted from the light j12 and the reflector
The heat rays of the light reflected by 1 are removed by a cold mirror 3, and the 3 primary colors R are separated by a dichroic mirror 4.5 for color separation.
, G, and H.

The separated light of the three primary colors is displayed on the LCD panel l0R10G, 1
After passing through 0B, the images are combined again, and a full-color image is projected onto the screen by the projection lens 11.

In such a liquid crystal projector-P', in order to obtain a high-brightness image, high-energy light passes through each liquid crystal panel IOR, IOG, and IOB.

Such high-energy light is transmitted to the liquid crystal panels 10R and IO.
G. If it passes through IOB, it will inevitably pass through the LCD panel IO.
Since the temperature of R, LOG, and IOB increases, cooling is required to protect the liquid crystal.

As shown in FIG. 4, this cooling is achieved by sucking outside air using a cooling fan 13' installed on the side of each liquid crystal panel IOR.
,,IOG, After passing through IOB, exhaust fan 31
The air that had risen was exhausted.

Note that a filter 32 is installed in front of the above-mentioned cooling fan 13' to supply clean air.

Furthermore, the filter 32 may become clogged, the cooling fan 13',
A temperature sensor 15' is installed to detect the temperature rise and turn off the set power when the internal gm temperature rises due to a failure of the exhaust fan 31 or the like.

[Problem to be Solved by the Invention J] In the liquid crystal projector P', when the temperature rises, the temperature sensor 15' detects this and turns the set power supply off to the liquid crystal panels IOR, IOG. ,
Although this is important for protecting the IOB, the cause of the temperature rise is unknown, so no appropriate measures could be taken.

This invention was made in view of the above-mentioned points, and detects the energy of light 1, the volume of cooling air, and the ambient temperature of the three conditions that determine the temperature of the liquid crystal panel, and uses the detected values to determine the temperature of the liquid crystal panel. To provide a cooling control mechanism for a liquid crystal projector capable of predicting the temperature of a liquid crystal panel, controlling the liquid crystal 70 dioctor to operate within a certain range of conditions, and monitoring the cause of failure.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention includes temperature detection means and wind speed detection means for detecting the ambient temperature and wind speed at each liquid crystal panel position, and a lamp for detecting run 7 energy. This device is characterized by comprising energy detection means and control means for controlling the temperature of each liquid crystal panel based on the data detected by each detection means.

U effect] In FIGS. 1 and 2 showing the embodiment of this invention,
The lamp energy W emitted from the light 12 is applied to the liquid crystal spring t.
In order to suppress the temperature of the liquid crystal panels IOR, IOC, 10B to Y℃ when hitting L-1OR, 10G, l OB, the T'C wind from the cooling fan 31 must be
m/s, the rotational speed of the cooling fan 13 and the exhaust fan can be controlled according to the lamp energy and ambient temperature.

In addition, by detecting the wind speed, it is possible to monitor filter clogging, and when the fan stops or the ambient temperature rises, the power supply is turned off.Furthermore, by detecting the lamp energy, it is possible to check when the light I2 should be replaced. will also be monitored.

E Example J Next, an example of the implementation of the cooling control mechanism for a liquid crystal 70 dioctor according to the present invention will be described in detail with reference to FIGS. 1 and 2.

The first QII is a *q configuration diagram showing an example of implementation of the cooling flJ# mechanism for the liquid crystal 70 dioctor according to the present invention.

In FIG. 1, the liquid crystal projector P includes a light source 2 with a reflector 1, a cold mirror 3, a guichroic mirror 4.5 for color separation, and a reflection mirror 6.7 for changing the optical path. Dichroi l Cumira-8 for color synthesis, three primary colors R, G, B liquid crystal panel IOR, LOG
, IOB, and a projection lens 11.

And 3 primary color R, G, B liquid crystal panel l0R10
G. Air passages 12 are formed on each front side of the IOB, and cooling fans 13 are installed on the sides of the air passages 12. be done.

An exhaust port (not shown) is provided on the opposite side of the cooling fan 13 .

A wind speed sensor 14 and a temperature sensor 15 are installed on the exit side of each air passage 12.

In addition, when the cold mirror 3 is soaked, the infrared sensor 16
The crotch! has been done.

The reflector 1 of the liquid crystal projector P reflects light emitted from a light source 2 using a parabolic reflector and emits the reflected light.

As the light source 2, for example, a metal halide lamp containing a metal halide is used.

The cold mirror 3 reflects only visible light and transmits infrared and ultraviolet rays.

A dichroic mirror 4 for color separation separately reflects red light and transmits other light.

The dichroic mirror 5 separates and reflects the blue light and transmits only the remaining green light.

The reflection mirror 6.7 for changing the optical path is a total reflection mirror that reflects all the incident light.

The dichroic mirror 8.9 for color synthesis is the liquid crystal panel I.
Combines the light that has passed through OR, LOG, and IOB.

The projection lens 11 projects the combined image light onto a screen (not shown).

The cooling fan 13 is a panel cooling means, has a filter (not shown) installed on the intake side, and is controlled by a control means described later.

The wind speed sensor 14 is a wind speed detection means, and is a wind speed detection means for each liquid crystal panel IO.
Detect the wind speed on the incident side of R, LOG, and IOH.

The temperature sensor 15 is a temperature detection means, and is a temperature detection means for each liquid crystal panel IO.
Detects the temperature on the incident side of R, IOG, and IOB.

The infrared sensor 16 is lamp energy detection means and detects infrared energy transmitted through the cold mirror 3.

In such a liquid crystal projector-P, the three primary colors R
, G, H, the temperature Y of the liquid crystal panels IOR, LOG, 10B is the lamp energy W emitted from the light s2,
It is determined by the wind speed (■) of the cooling air and the ambient temperature (T).

Therefore, in order to keep the temperature Y of the liquid crystal panels IOR, IOG, and IOB below a certain value, how many degrees Celsius and how many meters of wind is required depending on the lamp energy W emitted from the light s2.
Decide if it is necessary.

FIG. 2 is a block diagram showing an example of a cooling control mechanism for a liquid crystal projector according to the present invention.

In this twenty-first, the wind speed sensor 14 detects the three primary colors R, G.
, B is installed in front of the LCD panels 10R, LOG, and 10B (see Figure 1), and that's about it! The wind speed is detected and sent to the wind speed comparison means 18 in the microcomputer 17 which is the control means.

If the wind speed detected in the cooling fan I3 stop calculation is "0",
”, the power supply 19 is turned off to protect the liquid crystal panel 10.
to rOFF (V=O).

In addition, if the lamp energy W and the ambient temperature T do not change, but the filter clogging setting wind speed V set on the microcomputer 17 side is lower than that, the comparing means 18 determines that the filter is clogged and the clogging monitor is activated. 20 is lit to notify the user and have them take action (0kv≦V).

If the detected wind speed V is equal to or higher than the filter clogging setting wind speed V, the data is sent to the system controller 21 of the microcomputer 17 (V>■).

The temperature sensor 15, like the wind speed sensor 14, is placed in front of the liquid crystal panels IOR, LOG, and I0B (see Figure 1). The temperature at that position is detected as the ambient temperature T, and if the ambient temperature T detected by the temperature comparison means 22 is lower than the operating @concentration t, the data is sent to the microcomputer 1.
7 system controller 21 (Tit).

Further, when the detected ambient temperature T is higher than the upper limit operating temperature t, the power supply 19 is turned off to protect the liquid crystal panel 1o (T≧t).

The infrared sensor 16 is connected to the cold mirror 3 (see Figure 1, 9).
Distributed to trill! The lamp radiant energy W transmitted through the cold mirror 3 is detected and sent to a comparison means 23 for lamp energy.

If the detected lamp radiant energy W is larger than the lamp replacement monitor setting energy W, the data is sent to the system controller 2 (W>w).

If the detected lamp radiant energy W is smaller than the replacement monitor setting energy W, the lamp replacement monitor 24 is turned on (W≦w).

The system controller 21 of the microcomputer 17 guarantees the panel that the comprehensively determined function is based on each data sent from the wind speed comparison means 18, the temperature comparison means 22, and the lamp energy comparison means 23. If the temperature is lower than y, a command for continued use is sent and normal operation 25 is established (Y<y).

In addition, the overall judgment constant is panel protection F12! If the degree is greater than y, one of the voltages is turned off (Y≧y).

[Effects of the Invention] As described above, the cooling mum structure of the liquid crystal projector according to the present invention can detect the peripheral M temperature and wind speed at each liquid crystal panel position by using the data detected from the means for detecting the temperature and the wind speed at each position and the lamp energy detecting means. This is a mechanism that controls the temperature of the liquid crystal panel.

In other words, in order to suppress the temperature of the liquid crystal panel to Y'C, it is determined that the wind of T'C from the cooling fan is required to be V m/s, so the cooling fan and exhaust fan must be adjusted according to the lamp energy and ambient temperature. The rotation speed can be controlled.

In addition, by detecting the wind speed, it is possible to monitor whether the filter installed at the air intake of the cooling fan is clogged, and the power can be turned off when the fan is stopped or the ambient temperature rises. Furthermore, by detecting the lamp energy, it is also possible to monitor when the light 1 should be replaced.

[Brief explanation of drawings]

Figure 1 shows the cooling fi of a liquid crystal projector according to the present invention.
FIG. 2 is a functional block diagram showing an example of the implementation of the cooling control mechanism of a liquid crystal projector according to the present invention; FIG. 3 is a schematic configuration diagram of a conventional liquid crystal projector. , FIG. 4 is a schematic plan sectional view thereof.・LCD projector ・・Light source 10G IOB LCD panel 12・Air path 0R Cooling fan・Wind speed sensor Infrared sensor Microcomputer power supply clogged monitor Lamp replacement monitor

Claims (1)

[Claims] (1) Temperature detection means and wind speed detection means for detecting the ambient temperature and wind speed at each liquid crystal panel position, lamp energy detection means for detecting lamp energy, and the temperature of each liquid crystal panel based on the data detected from each detection means. A cooling control mechanism for a liquid crystal projector, comprising a control means for controlling the liquid crystal projector.