JP2005227537A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cope with both of the completion of cooling down a lamp in a short time and the reduction of a noise at cooling down the lamp. <P>SOLUTION: The projector is provided with a lamp 1, liquid crystal panels 2R, 2G and 2B on which light emitted from the lamp 1 is made incident so as to modulate the light in accordance with image information, a projection lens 5 for projecting the modulated light from the liquid crystal panels, a fan 8 for cooling the lamp 1, a control part 7 for controlling the liquid crystal panels 2R, 2G, 2B and the fan 8, and an operating part 9 for operating the projector, and when the lamp 1 is turned off by operating the operating part 9 from outside the projector, the fan 8 is rotated at high speed so as to cool down the lamp 1, on the other hand, when the lamp 1 is automatically turned off, not by operating from the outside, but with a previously set work of the control part 7, the fan 8 is rotated at low speed so as to cool down the lamp 1. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a projector having a function of cooling a light source in a projector.

When the light source of the projector is turned on and then turned off by turning off the power of the projector, etc., a cool-down process is performed to cool the light source that has become hot due to lighting using a fan. It has been broken. Since the time required for this cool-down process is usually preferably as short as possible, it is performed by rotating the fan as fast as possible (for example, Patent Document 1).
JP 2003-248269 A

Currently, projectors are widely used in homes for watching movies and watching sports, but when using projectors in homes, it is assumed that the user will fall asleep with the projector on. In such a case, it is conceivable that the power of the projector is automatically turned off after a predetermined time has elapsed. However, when the power of the projector is turned off, the above-described cool-down function is activated and the fan starts to rotate at a high speed. When the fan starts to rotate at high speed, the fan's rotating sound becomes a considerable noise in a small room or at midnight, which may annoy people who have fallen asleep while watching the projected image of the projector and those around them.
The present invention has been made in order to solve the above-described problem. By appropriately changing the cool-down mode of the light source performed by the fan when the light source is turned off according to the turn-off situation, the cool-down time can be shortened. It is an object of the present invention to provide a projector that can cope with both the end of the projector and the reduction in noise during cool-down.

  A projector according to the present invention cools a light source, a light modulator that receives light from the light source and modulates the light according to image information, a projection lens that projects the modulated light from the modulator, and the light source And a control unit for controlling the light source, the light modulation device and the fan, and an operation unit for operating the projector, and the light source is turned off by an operation from outside the projector with respect to the operation unit. The fan is rotated at a high speed to cool down the light source, and when the light source is automatically turned off by a preset action in the control unit without any external operation, the fan is rotated at a low speed to cool the light source. It is characterized by going down. Thereby, when the user consciously stops the projector, the cool-down is caused by the high-speed rotation of the fan. On the other hand, when the projector is automatically stopped, the cool-down is caused by the low-speed rotation of the fan. Therefore, normally, cool-down is completed in a short time, but noise can be reduced during cool-down when the user falls asleep while looking at the image of the projector.

  Further, the operation of the control unit is an operation of turning off the light source after elapse of a preset time input to a timer provided in the projector, and when there is no input of image information for a predetermined time to the projector. The light source is turned off or the light source is turned off when there is no operation input from the outside of the projector for a predetermined time with respect to the operation unit. Thus, the light source can be automatically turned off and the subsequent cool-down can be performed with low noise.

  Further, when an operation for rotating the fan at a high speed is applied to the operation unit while the fan is rotating at a low speed, the fan is changed to a high speed to cool down the light source. . Thereby, even during the cool-down due to the low-speed rotation, the processing time can be reduced by changing to the cool-down due to the high-speed rotation if desired.

(Projector configuration)
FIG. 1 is a block diagram showing a configuration of a projector according to an embodiment of the present invention. As shown in the figure, this projector includes a lamp 1 serving as a light source, and a dichroic mirror that separates illumination light from the lamp 1 into red (R), green (G), and blue (B) light. The optical system 3 receives the separated color lights, modulates them according to predetermined image information, and generates modulated images. The modulated light from the liquid crystal panels 2R, 2G, 2B and the liquid crystal panels 2R, 2G, 2B is generated. A cross dichroic prism 4 to be combined and a projection lens 5 for projecting the combined modulated light are provided. This projector is also based on a lamp driving circuit 1A for driving the lamp 1, an image signal input unit 2I for inputting an image signal from the outside, and an image signal input from the image signal input unit 2I to the liquid crystal panels 2R, 2G, 2B. An image processing circuit 2 for supplying predetermined information, a speaker 6 and an audio processing circuit 6A for outputting sound, a fan 8 for cooling the lamp 1, a fan driving circuit 8A for driving the fan 8, and the like. It is controlled by a control unit 7 composed of a CPU or the like.

  The projector further monitors the temperature of an operation unit 9 provided with various operation switches for operating the projector, a power supply unit 10 connected to an external commercial power source and serving as a power supply source in the projector, and a lamp 1. The temperature sensor 11 is provided and is also controlled by the control unit 7. The operation unit 9 includes a power switch 9A for switching the projector to either an ON state in which projection is possible or an OFF state in which projection is not possible, a timer 9B for monitoring the set time that allows time setting input, and a fan. A change-over switch 9C for switching the rotational speed 8 from low speed (first speed) to high speed (second speed), various projection control buttons (not shown) for performing control related to projection, and the like are arranged.

(Projector action)
The projector is capable of projecting an image from the projection lens 5 by turning on the power switch 9A of the operation unit 9 to turn on the projector, turning on the lamp 1 and rotating the fan 8, and the like. It will be in a standby state. In this state, the projection control button of the operation unit 9 is operated to project a desired image from the projection lens 5 in a desired projection mode. Also, during this projection, the projection mode is adjusted by operating the projection control button. On the other hand, the power source of the projector is turned from ON to OFF according to the following mode (1) or (2), and the lamp 1 is also turned off in conjunction with this. Then, after the cool-down process of the lamp 1 is performed according to the lighting state of the lamp 1, the projector is completely stopped. This cool-down process is automatically executed by the action set in the control unit 7.

(Projector power-off mode)
(1) Turn off the power switch 9A of the operation unit 9 to turn off the projector.
(2) The projector is automatically turned off by an action set in advance in the control unit 7 without being operated by the operation unit 9. As a concrete example of this,
(2a) A time to use the projector is determined in advance, and the time is set and input to the timer 9B of the operation unit 9. After the set time has elapsed, the power of the projector is turned off by the action of the control unit 7.
(2b) If no image information is input to the image processing circuit 2 for a predetermined time, the projector is turned off by the action of the control unit 7 after the time has elapsed.
(2c) When there is no operation input from the outside of the projector for a predetermined time with respect to the operation unit 9, it is conceivable that the power of the projector is turned off by the action of the control unit 7 after the elapse of the time.

(Example of cool-down process 1)
When the power of the projector is turned off in the mode (1) above, after the lamp 1 is turned off, the fan 8 is rotated at a high speed (second speed), for example, a speed close to full power, to cool the lamp 1. When the lamp 1 reaches a predetermined temperature, the fan 8 stops. According to this, the cool-down process of the lamp 1 is completed in a short time, which is suitable when the projector is moved by unplugging the power outlet after using the projector.

(Example of cool-down process 2)
When the power of the projector is turned off in any one of the above aspects 2a to 2c, after the lamp 1 is extinguished, the fan 8 is rotated at a low speed (first speed), for example, the rotation of the fan 8 does not cause noise. The lamp 1 is cooled by rotating at a speed. When the lamp 1 reaches a predetermined temperature, the fan 8 stops. According to this, although the time required for the cool-down process of the lamp 1 is slightly longer, the cool-down is executed with low noise, which is suitable when the user falls asleep while watching the projection image of the projector. Note that this low speed (first speed) may be selected from, for example, 50%, 60%, and 70% of the high speed (second speed) according to the environment.

  By the way, in Example 2 above, when the power switch 9A of the operation unit 9 is turned off before the set time elapses, the projector termination mode is the mode described in Example 1 above. In addition, even when the fan 8 is rotating at a low speed (first speed) according to the second aspect of the above example, by operating the changeover switch 9 </ b> C provided in the operation unit 9, the high speed (second speed) rotation is achieved. It is possible to switch.

  FIG. 2 is a flowchart showing a cool-down process of the lamp in the projector. This cool-down process starts when the lamp 1 that has been lit up is extinguished, for example, when the power of the projector is switched from the ON state to the OFF state. The processing mode differs depending on the lighting mode.

  First, when the power of the projector is turned off by the power switch 9A of the operation unit 9 (S1), the fan 8 is rotated at high speed by the control unit 7 and the fan drive circuit 8A to cool the lamp 1 (S2). In this case, the temperature sensor 11 monitors the temperature of the lamp 1 (S3), and the fan 8 is rotated at a high speed until the temperature reaches a predetermined temperature (S2). When the temperature of the lamp 1 reaches a predetermined temperature, the fan 8 is stopped and the cool-down process is terminated (S4).

  On the other hand, there is no input of image information for a predetermined time to the image processing circuit 2 due to time setting input to the timer 9B, or a predetermined time for the operation unit 9 from the outside of the projector. When the projector power is turned off due to the absence of the operation input (S6), the lamp 8 is cooled by rotating the fan 8 at a low speed by the control unit 7 and the fan drive circuit 8A (S7). During the low-speed rotation, the presence / absence of an input from the changeover switch 9C is monitored (S8). If there is no input, the fan 8 is rotated at a low speed (S7). If there is an input, the fan 8 is rotated at a high speed. (S2). The temperature of the lamp 1 is monitored by the temperature sensor 11 (S3, S9), and the fan 8 is rotated at a low speed (S7) or at a high speed until the temperature reaches a predetermined temperature (S2). When the temperature of the lamp 1 reaches a predetermined temperature, the fan 8 is stopped and the cool-down process is terminated (S4).

  In the projector described above, the cool-down process of the lamp 1 when the projector power is turned off is completed in a short time according to the usage status of the projector, and the process time is extended and executed with low noise. Since it is provided with two types of modes to be operated, it is a user-friendly projector.

In the present invention, the mode in which the projector is automatically turned off by the action set in advance in the control unit 7 without being operated from the outside of the projector is not limited to the above-described 2a to 2c. Any aspect of the above is also included.
In the present invention, the term “low speed (first speed)” or “high speed (second speed)” related to the rotational speed of the fan 8 indicates a relative relationship between the first speed and the second speed. It is used and does not indicate a specific value.
Further, the condition for stopping the fan at the time of cool-down may be based on the passage of time determined for high-speed rotation and low-speed rotation, instead of the above-described temperature.

1 is a block diagram showing a configuration of a projector according to an embodiment of the invention. 2 is a flowchart showing cool-down processing of the projector shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Lamp, 1A ... Lamp drive circuit, 2 ... Image processing circuit, 2I ... Image signal input part, 2R, 2G, 2B ... Liquid crystal panel, 3 ... Color light separation optical system, 4 ... Cross dichroic prism, 5 ... Projection lens, DESCRIPTION OF SYMBOLS 6 ... Speaker, 6A ... Audio processing circuit, 7 ... Control part, 8 ... Fan, 8A ... Fan drive circuit, 9 ... Operation part, 9A ... Power switch, 9B ... Timer, 9C ... Changeover switch, 10 ... Power supply part, 11 ... temperature sensor.

Claims (5)

A light source, a light modulation device that receives light from the light source and modulates the light according to image information, a projection lens that projects the modulated light from the modulation device, a fan that cools the light source, and the light source A control unit for controlling the light modulation device and the fan, and an operation unit for operating the projector,
When the light source is turned off by an operation from the outside of the projector with respect to the operation unit, the fan is rotated at a high speed to cool down the light source, and the light source is preliminarily set in the control unit without being operated from the outside. When the projector is automatically turned off, the projector is rotated at a low speed to cool down the light source.   The projector according to claim 1, wherein the operation of the control unit is an operation of turning off the light source after elapse of a time preset in a timer provided in the projector.   The projector according to claim 1, wherein the operation of the control unit is an operation of turning off the light source when no image information is input to the projector for a predetermined time.   2. The projector according to claim 1, wherein the operation of the control unit is an operation of turning off the light source when there is no operation input from the outside of the projector for a predetermined time with respect to the operation unit.   2. The light source is cooled down by changing the fan to a high speed rotation when an operation for rotating the fan at a high speed is applied to the operation unit while the fan is rotating at a low speed. The projector according to any one of 1 to 4.

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