JP2008090192A - Image projection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily keep an object to be controlled within a fixed temperature range by reducing an influence of heating/cooling air on the object to be controlled. <P>SOLUTION: Temperature variation of a display element is controlled to be within a constant range by providing a first blast means of sending air to cool a light source and air warmed by the light source, in a duct between the light source and a branch of the duct, providing a second blast means of blowing the air sent by the first blast means to the display element, and controlling the operations of the first and second blast means by a control means 15 in accordance with the state of the light source and a measured value of the internal temperature sensor. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image projection apparatus using an optical path deflecting element that changes the direction of light according to an electric signal, and is suitable for application to an electronic display apparatus such as a projection display.

  Since the characteristics of the liquid crystal material are temperature dependent, when a liquid crystal material is used as the optical path deflection element, the optical path deflection amount varies depending on the temperature around the optical path deflection element. For example, when one frame is divided into a plurality of subfields, the apparent pixel position is moved for each subfield, and the divided subfields are used in an image projection apparatus that displays images in order to display the subfields in order. As a result, a dot position shift of the display image occurs, which causes a decrease in contrast.

  Among the display elements used in the image projection apparatus, the characteristics of display elements using liquid crystal such as a transmissive liquid crystal panel or LCOS (Liquid Crystal on Silicon) have temperature dependency. In many cases, these temperature controls must be performed at a temperature higher than the normal room temperature.

  A fan is placed at a position away from the transmissive LCD panel, and the cool air taken in by the fan or the warm air from the light source is guided to the position where the LCD panel is installed by a duct provided between the fan and the LCD panel to control the temperature. There is technology to do.

  In general, temperature control uses air having a temperature difference from a liquid crystal panel when heating and cooling are actively performed. In order to perform faster control, air having a higher temperature difference is used.

  Since the air flow path used for temperature control of the duct and the liquid crystal panel is an integrated sealed space, even if aggressive temperature control is not performed, after the active temperature control, the liquid crystal panel The ambient temperature is maintained at the control temperature. This phenomenon is particularly conspicuous in the control during heating, and this has the great disadvantage that it is difficult to maintain the liquid crystal panel in a certain temperature range. Further, switching between cold air and hot air is performed by a mechanical mechanism such as a door, and so many parts are required for the mechanism, resulting in high cost.

  In addition, in the case where a mechanical mechanism is provided to blow the hot air from the light source to the duct leading to the liquid crystal panel, the efficiency is poor because the hot air also passes through the opening. Also, when a hot air intake fan is provided, the efficiency is poor because the hot air is obtained from the same space as the exhaust fan.

Here, an optical path deflecting element using a liquid crystal material, an internal temperature sensor installed in a place where the temperature tendency of the optical path deflecting element or the optical path deflecting element can be estimated, and a blowing means for sending wind to the optical path deflecting element And an external temperature sensor installed at a position where the temperature of the air blown by the blower means can be measured, and the blower amount of the blower means is controlled by the detected temperature of the external temperature sensor and the detected temperature of the internal temperature sensor. Thus, a technique for controlling the temperature change of the optical path deflecting element within a certain range is disclosed (for example, see Patent Document 1).
JP 2004-279924 A

  However, in the prior art, as the heating element for heating the optical path deflecting element, a heating element such as a heater or a heating wire is used, and new energy is required to generate heat. It was.

  Therefore, in the present invention, with respect to temperature control of a display element using an optical deflection element or liquid crystal, a control object for controlling the temperature of the display element (including a liquid crystal panel), the optical deflection element, etc. using a duct branching in two directions. If it is not installed in a closed flow path integrated with the duct and active temperature control is not performed, air for heating / cooling is flown through the duct that has little influence on the liquid crystal panel, so that it can be controlled. The influence of air for heating and cooling is reduced, and it is easy to maintain the controlled object in a certain temperature range. In addition, it is efficiently used to control the warm air after cooling the light source, does not use a new heat source and energy, and does not use a mechanical drive mechanism other than the air blowing means. An object of the present invention is to provide an image projection apparatus capable of performing temperature control with energy saving.

  A first aspect of the present invention is an image projection apparatus that projects light from a light source onto a display element, and enlarges and projects a display image of the display element onto a screen by a projection lens. The image projection apparatus has a plurality of openings that communicate with outside air. And one or more internal temperature sensors installed in a place having a display element or a substitute characteristic thereof, and a duct having a branching structure, for cooling the light source and blowing air warmed by the light source The first air blowing means is provided in the duct between the light source and the branch of the duct, and a part or all of the air blown by the first air blowing means is supplied to the first branch duct which is one of the branched ducts. A second air blowing means for blowing air to the display element; a control means for controlling the operation of the first and second air blowing means; the first and second according to the light source status and the measured value of the internal temperature sensor. Blast of By controlling by the control means the operation of the stage, an image projection apparatus characterized by controlling the temperature variation of the display element to a certain range.

  According to a second aspect of the present invention, there is provided an image projection apparatus that projects light from a light source onto a display element, projects an image displayed on the display element through a light deflection element, and projects the enlarged image onto a screen by a projection lens. A plurality of openings communicating with each other, one or more internal temperature sensors installed in a place having a light deflecting element or a substitute characteristic thereof, and a duct having a branching structure, so that the light source can be cooled and heated by the light source. The first air blowing means is provided in the duct between the branch of the duct from the light source, and the first air blowing means blows air to the first branch duct, which is one of the branched air ducts. A second blowing means for blowing part or all of the air to the light deflecting element, a control means for controlling the operation of the first and second blowing means, the condition of the light source and the measurement of the internal temperature sensor In value There, first, by controlling by the control means of an operation of the second blowing means, an image projection apparatus characterized by controlling the temperature variation of the light deflector to a certain range.

  According to a third aspect of the present invention, there is provided an image projection apparatus that projects light from a light source onto a display element, and projects a display image of the display element through a light deflection element and enlarges and projects it onto a screen by a projection lens. A plurality of openings that communicate with each other, one or more internal temperature sensors installed in a place having a light deflection element and a display element or a substitute characteristic thereof, a duct having a branching structure, cooling the light source, and light source The first air blowing means for blowing air warmed by the air is provided in the duct between the branch of the duct from the light source, and the first air blowing means is connected to the first branch duct which is one of the branched ducts by the first air blowing means. A second air blowing means for blowing a part or all of the blown air to the light deflecting element and the display element; a control means for controlling the operation of the first and second air blowing means; as well as An image projection apparatus characterized by controlling the temperature change of the light deflection element and the display element within a certain range by controlling the operation of the first and second air blowing means by the control means in accordance with the measured value of the temperature sensor. It is.

  According to a fourth aspect of the present invention, in the image projection device according to any one of the first to third aspects, the first branch duct is installed at a lower position than the other branched ducts, and the first air blowing means is provided. It operates and has a structure in which the total pressure when the second blowing means is stopped is lower than that of other branched ducts.

  According to a fifth aspect of the present invention, in the image projection device according to any one of the first to fourth aspects, the branch angle from the duct to the first branch duct is made larger than that of the other duct branched. .

  According to a sixth aspect of the present invention, in the image projection apparatus according to any one of the first to fifth aspects, the cross-sectional area of the first branch duct is made smaller than that of the other branched branch.

  According to a seventh aspect of the present invention, in the image projection apparatus according to any one of the first to fifth aspects, the ventilation resistance of the first branch duct is provided by providing a second air blowing means, so that it is more than the other branched branch duct. It is characterized by being enlarged.

  According to an eighth aspect of the present invention, in the image projection device according to any one of the first to seventh aspects, a duct is used to connect between a light source and an opening of the image projection device by a duct.

  According to a ninth aspect of the present invention, in the image projection device according to any one of the first to eighth aspects, the first and second air blowing means are operated in accordance with the state of the light source and the measured value of the internal temperature sensor. ON / OFF is controlled by a control means.

  According to a tenth aspect of the present invention, in the image projection apparatus according to any one of the first to eighth aspects, the second air blowing means controls the rotational speed by the control means in accordance with the measured value of the internal temperature sensor. It is characterized by.

  The invention according to claim 11 is the image projection apparatus according to any one of claims 1 to 8, wherein the first air blowing means is a state of a light source, a measured value of an internal temperature sensor, and a second air blowing means. The number of revolutions is controlled by the control means according to the operating situation.

  A twelfth aspect of the present invention is the image projection apparatus according to any one of the first to eleventh aspects, wherein a third blower for cooling one or both of the light deflection element and the display element is provided in the image projection apparatus. Means are provided.

  According to a thirteenth aspect of the present invention, in the image projection apparatus according to any one of the first to twelfth aspects, the third blower means turns on / off the operation by the control means according to the measured value of the internal temperature sensor. It is characterized by controlling.

  According to a fourteenth aspect of the present invention, in the image projection apparatus according to any one of the first to twelfth aspects, the third blower means controls the rotational speed by the control means in accordance with the measured value of the internal temperature sensor. It is characterized by.

  According to a fifteenth aspect of the present invention, in the image projection apparatus according to any one of the first to eleventh aspects, the first air blowing means and the control means capable of blowing air in the reverse direction are provided. .

  According to the present invention, the influence of heating / cooling air on the controlled object is reduced, and it is easy to maintain the controlled object in a certain temperature range. In addition, it is efficiently used to control the warm air after cooling the light source, does not use a new heat source and energy, and does not use a mechanical drive mechanism other than the air blowing means. Temperature control can be performed with energy saving.

  Next, the configuration of the first embodiment of the present invention will be described with reference to the drawings (fan 2).

  FIGS. 1 to 3 are explanatory diagrams showing a configuration relating to the temperature control of the optical path deflecting element 9 and the display element 8 in the image projection apparatus according to the present embodiment and the flow of air.

  Various types of display elements 8 such as DLP (Digital Light Processing), a transmissive liquid crystal panel, and LCOS are used for the display element 8 of the projector as an image projection apparatus, and there are various types of display elements. Then, an image projection apparatus provided with a three-plate projector using LCOS for each color of RGB as a display element is shown. Of course, the present invention does not depend on the type of display element or the number of display elements.

  The LCOS three-plate projector uses optical components such as mirrors, integrators, and PBSs in addition to the drawings shown in the drawing, but in this embodiment, only the portions necessary for the explanation related to temperature control of the present invention are shown. I will do it. The temperature control target includes both the light deflection element 9 and the display element 8 in both cases. Here, the temperature control of both is shown. The element 9 and the display element 8 are described as control targets.

  A lamp 2 that is a light source is installed beside the opening 1 that communicates with the outside of the image projection apparatus, and a fan 3 that is a first blowing means is installed in the duct 4 in a direction different from that of the opening 1. The duct 5 and the duct 6 that are one branch duct are branched into the duct 5 that is positioned lower than the duct 6, and a fan 7 that is a second blowing means is installed.

  The operation of the fan 3 is controlled by the control means 15 according to the measured values of the light source temperature sensor 16 and the internal temperature sensor 13, and the fan 7 is controlled by the control means 15 according to the measured value of the internal temperature sensor 13. Is done. The light source temperature sensor 16 is installed in the vicinity of the light source, and the internal temperature sensor 13 is installed in the display element 8, the light deflection element 9, or a place that has a substitute characteristic that is a control target, but is omitted from the drawing.

  When the fluid air moves, it always has a static pressure that is not related to the movement of the air and a dynamic pressure related to the velocity of the airflow, and this sum is called the total pressure.

  FIG. 1 shows a case where the controlled object is not warmed. The fan 7 does not rotate. The property of rising above the warm air, and the branched duct 6 has a structure in which the first blowing means operates compared to the duct 5 and the total pressure when the second blowing means is stopped is lower than that of the duct 5. Therefore, the warm air does not go to the duct 5 and is discharged through the duct 6 so that the control target is not affected.

  FIG. 5 shows the branching angle of the duct 5 and the duct 6 with respect to the duct 4, FIG. 6 shows the cross-sectional area of the branching part of the duct 5 and the duct 6, and FIG. It is explanatory drawing about raising ventilation resistance by.

  As shown in FIG. 5, by making the branch angle of A larger than the branch angle of B, the pressure loss coefficient of the duct 6 becomes larger than that of the duct 5. Air from the duct 4 becomes difficult to flow.

  As shown in FIG. 6, by making the cross-sectional area C of the branch portion smaller than D, the air from the duct 4 is less likely to flow in the duct 6 than in the duct 5.

  By providing the fan 7 in the duct 6 as shown in FIG. 7, the airflow resistance is increased by narrowing the space through which air flows. As a result, the air from the duct 4 is less likely to flow in the duct 6 than in the duct 5.

  2 and 3 show a case where the controlled object is warmed. The object to be controlled includes both the case of the light deflecting element 9 and the case including the display element 8, but here, the case where both temperature controls are performed is shown.

  When the fan 3 rotates, the wind is sent from the opening 1 which is an opening to the inside of the device, whereby the lamp 2 is cooled.

  The warm air warmed by cooling the lamp 2 passes through the fan 3 and is sent to the duct 4.

  When the hot air passing through the duct 4 warms the object to be controlled, the hot air in the duct 4 is rotated by rotating the fan 7, which is the second blowing means in the duct 5 positioned lower than the duct 6. Is sent in the direction of the duct 5 and sent to the controlled object outside the duct 5.

  FIG. 3 shows a case where the air blowing capacity of the fan 3 exceeds the air blowing capacity of the fan 7, but the warm air outside the air blowing capacity of the fan 7 flows in the direction of the duct 5 and may affect the controlled object. Absent.

  In the explanatory diagrams after FIG. 1, an open space is formed from the duct 5 to the controlled object. However, in order for the wind from the duct 5 to affect the controlled object efficiently and evenly, the shape of the duct 5 therebetween May be adjusted to the position of the control object, the duct 5 may be extended to the control object, or a structure surrounding the control object may be used.

  FIG. 4 shows a schematic explanatory diagram relating to temperature control using the control means 15. The temperature control of the object to be controlled is based on the output of a plurality of temperature sensors including the internal temperature sensor 13 installed in the control object or a place having the substitute characteristic and the light source temperature sensor 16 for checking the state of the light source. The temperature is input to the temperature control circuit 14 via the D converter 12 and the temperature of each sensor is detected. This value can be used by controlling the operation of the fan 3 and the fan 7.

  In FIG. 4, only the internal temperature sensor 13 and the light source temperature sensor 16 are connected as sensors. However, when other temperature sensors are used, A / D converters are provided in accordance with the number of the temperature sensors. The temperature sensor output is converted and input to the temperature control circuit 14 for control.

  When the value of the internal temperature sensor 13 is less than the set value, control for warming the control target is performed, and when the value is equal to or greater than the set value, control for not warming is performed.

  Further, by referring to the past and present temperatures, more delicate temperature control can be performed.

  As described above, it is possible to provide an image projection apparatus that can perform energy-saving temperature control that heats a control object using heat that was originally discarded without providing a heating element for heating the control object. did it.

  Next, a second embodiment of the present invention will be described (cooling fan).

  FIGS. 9 to 11 are explanatory views showing the direction of air flow related to temperature control, in which a cooling fan 10 is added as a third blowing means to the first embodiment.

  The light source temperature sensor 16 is installed in the vicinity of the light source, and the internal temperature sensor 13 is installed in the display element 8, the light deflection element 9, or a place that has a substitute characteristic that is a control target, but is omitted from the drawing.

  When the control object is not positively affected as shown in FIG. 9 and when the control object is warmed as shown in FIG. 10, the operations of the fan 3 and the fan 7 are the same as those in the first embodiment. At rest. The operation of the fan 10 is controlled by the control means 15. The operation of the fan 10 is controlled by the temperature control circuit 14 through the driver 11.

  In this embodiment, the configuration is as shown in FIG. Outputs of a plurality of temperature sensors including an internal temperature sensor 13 installed in a controlled object or a place having a substitute characteristic and a light source temperature sensor 16 for viewing the state of the light source are passed through an A / D converter 12. The temperature is input to the temperature control circuit 14 and the temperature of each sensor is detected. This value can be used by controlling the operations of the fan 3, the fan 7, and the fan 10.

  In FIG. 8, only the internal temperature sensor 13 and the light source temperature sensor 16 are connected as sensors. However, when other temperature sensors are used, A / D converters are provided in accordance with the number of the temperature sensors. The temperature sensor output is converted and input to the temperature control circuit 14 for control.

  When the control target in FIG. 11 is cooled, the fan 10 rotates and the control target can be cooled by sending ambient air having a temperature lower than that of the control target or outside air in the direction of the control target.

  9 to 11, the fan 10 is illustrated on the upper side of the control target, but the installation position is not limited to this as long as it is installed at a position where air can be blown to the control target.

  These temperature controls control the rotational operation of each fan by using values of at least one temperature sensor including an internal temperature sensor installed at a place having at least the optical path deflecting element or a substitute characteristic thereof. Can be performed.

  Other measurement objects of the temperature sensor include the temperature around the duct 4 and the cooling fan, and by measuring these, more delicate control can be performed.

  When the value of the internal temperature sensor 13 is equal to or lower than the lower limit set value, control to warm the control target is performed, and when the value is equal to or higher than the upper limit set value, cooling control is performed. By newly providing the fan 10 in this way, the controlled object can be actively cooled, and an image projection apparatus capable of quickly controlling the temperature can be provided.

  Next, a third embodiment of the present invention will be described (rotation control fan).

  By making the fan 3, the fan 7, and the fan 10 of the first and second embodiments into fans whose rotation can be controlled, it is possible to adjust the amount of air blown to the controlled object.

  In the configuration of the first and second embodiments, the influence on the controlled object can be increased or decreased by increasing or decreasing the rotation of the fan 7.

  In the configuration of the third embodiment, the influence on the controlled object can be increased or decreased by increasing or decreasing the rotation of the fan 7 or the fan 10 during operation. These temperature controls control the rotation speed and operation of each fan by using the values of at least one temperature sensor including an internal temperature sensor installed in a place having at least the optical path deflecting element or its substitute characteristics. This can be done by controlling by means 15.

  The rotation speed is set according to the temperature. As described above, by using a fan whose rotation can be controlled as described above, the amount of blown air can be controlled, and thereby the temperature control of the controlled object can be performed more delicately.

  Next, a fourth embodiment of the present invention will be described (reversing fan).

  FIG. 4 is used as a schematic explanatory diagram relating to temperature control using the control means 15 of the present embodiment. 12 and 13, the light source temperature sensor 16 is installed in the vicinity of the light source, the internal temperature sensor 13 is installed in the display element 8 to be controlled, the light deflection element 9 or a place having the substitute characteristics, and the driver 11 is controlled. Although it is in the means 15, it is not shown and is omitted.

  FIG. 12 is an explanatory diagram showing the direction of air flow related to temperature control using a fan 3 having a function of rotating in the front-rear direction to the fan 3 that is the first blowing means of the first embodiment. is there. The fan 3 is controlled by the control unit 15, and the operation of the fan 15 is controlled by the temperature control circuit 14 through the driver 11.

  The fan 3 is a direct-current drive fan. When the voltage is reversed, the rotation is reversed and air can be blown in the opposite direction. When the control object is warmed and has no effect, the same control as in the first embodiment is performed. However, when the cooling control is performed, the fan 3 is rotated so as to blow in the light source direction. Cooling air from the duct 6 is blown by the fan 3 into the duct 4 other than the lamp 2 from the opening 1.

  As the fan 7 rotates, the cooling air passes through the duct 5 and affects the controlled object, thereby cooling. Depending on the total pressure of the duct 5 and the duct 6, a small amount of air may flow from the duct 6 to the duct 4 as shown in FIG.

  These temperature controls control the rotational operation of each fan by using values of at least one temperature sensor including an internal temperature sensor installed at a place having at least the optical path deflecting element or a substitute characteristic thereof. Can be performed.

  Other measurement objects of the temperature sensor include the temperature of the duct 4 and the duct 5 and the like, and by measuring these, more delicate control can be performed.

  When the value of the internal temperature sensor 13 is equal to or lower than the lower limit set value, control to warm the control target is performed, and when the value is equal to or higher than the upper limit set value, cooling control is performed. As described above, by using a fan that can reverse the blowing direction of the fan 3 that is the first blowing unit, an image that can positively control the temperature of the controlled object without providing a cooling blowing unit. Projection device could be provided.

  Below, the purpose and action effect of each claim will be described.

(Object of claim 1)
There is little influence of air used for temperature control other than during active temperature control on the display element, and heat-efficient and energy-saving heat control using the exhausted energy is performed.

(Object of claim 2)
The temperature of the optical path deflecting element is less affected by air used for temperature control other than during active temperature control, and temperature control with high thermal efficiency is performed using the exhausted energy.

(Object of claim 3)
The temperature of the display element and the optical path deflecting element is less affected by the air used for temperature control other than during active temperature control, and temperature control with high thermal efficiency is performed using the exhausted energy.

(Object of claim 4)
The influence of unnecessary warm air on the display element and the light deflection element is reduced.

(Object of claim 5)
The influence of unnecessary warm air on the display element and the light deflection element is reduced.

(Object of claim 6)
The influence of unnecessary warm air on the display element and the light deflection element is reduced.

(Object of claim 7)
The influence of unnecessary warm air on the display element and the light deflection element is reduced.

(Object of claim 8)
Reduce the influence of hot air on other components in the image projection device.

(Object of claim 9)
Temperature control is performed according to the condition of the light source and the measured value of the internal temperature sensor.

(Object of claim 10)
Perform more delicate temperature control.

(Object of claim 11)
Delicate temperature control is performed in accordance with the operation status of the second blowing means.

(Object of claim 12)
Perform temperature control that actively heats and cools.

(Object of claim 13)
Cooling temperature control is performed according to the measurement value of the internal temperature sensor.

(Object of claim 14)
Perform more delicate cooling temperature control.

(Object of claim 15)
Controls the temperature of heating and cooling and cools the light source with a small number of blowing means.

(Operational effect on claim 1)
By providing a branch in the duct, the influence of air used for temperature control other than during active temperature control on the display element is reduced, and hot air after cooling the light source is used for temperature control to warm the display element. Thus, the temperature change of the display element can be controlled within a certain range without using new energy for heating.

(Operational effect on claim 2)
By providing a branch in the duct, the influence of air used for temperature control other than during active temperature control on the light deflection element is reduced, and the warm air after cooling the light source is used for temperature control to warm the light path deflection element. By using this, the temperature change of the optical path deflecting element can be controlled within a certain range without using new energy for heating.

(Operational effect on claim 3)
By providing a branch in the duct, the influence of air used for temperature control other than during active temperature control on the display element and the light deflection element is reduced, and the light source is used for temperature control that warms both the display element and the optical path deflection element. By using the warm air after cooling, the temperature change of the display element and the optical path deflecting element can be controlled within a certain range without using new energy for heating.

(Operational effect on claim 4)
The first branch duct is installed at a lower position than the other branched ducts, and the first blowing means is operated, and the total pressure when the second blowing means is stopped is higher than that of the other branched branches. By providing a low structure, the influence of unnecessary warm air on the display element and the light deflection element can be reduced.

(Operational effect on claim 5)
By making the branch angle to the first branch duct larger than that of the other branched ducts, it is possible to provide a structure in which the total pressure of the first branch duct in the lower position is lower than that of the other branched ducts. .

(Operational effect on claim 6)
By making the cross-sectional area of the first branch duct smaller than that of the other duct branched, it is possible to provide a structure in which the total pressure of the first branch duct is lower than that of the other duct branched.

(Operational effect on claim 7)
A structure in which the total pressure of the first branch duct is lower than that of the other branched ducts by making the ventilation resistance of the first branch duct larger than that of the other branched ducts by providing the second blowing means. Can be provided.

(Operational effect on claim 8)
The duct connects between the light source and the opening of the image projection apparatus, and the flow path is provided, so that the influence of warm air on other components in the image projection apparatus can be reduced.

(Operational effect on claim 9)
By controlling ON / OFF of the operation of the first and second air blowing means according to the state of the light source and the measured value of the internal temperature sensor by the control means, it is possible to perform temperature control with a constant air flow rate.

(Operational effect on claim 10)
More delicate temperature control can be performed by controlling the number of rotations of the second air blowing means by the control means in accordance with the measured value of the internal temperature sensor.

(Operational effect on claim 11)
By controlling the number of rotations of the first blowing means by the control means according to the status of the light source, the measured value of the internal temperature sensor, and the operating status of the second blowing means, the second blowing The effect by the ventilation of a means can be made more stable, and more delicate temperature control can be performed.

(Operational effect on claim 12)
By providing the third air blowing means for cooling, temperature control for positively heating and cooling can be performed.

(Operational effect on claim 13)
By controlling the ON / OFF of the operation of the third air blowing means according to the measured value of the internal temperature sensor by the control means, it is possible to perform temperature control for cooling with a constant air flow rate.

(Function and effect on claim 14)
More delicate temperature control can be performed by controlling the number of rotations of the third air blowing means by the control means in accordance with the measured value of the internal temperature sensor.

(Operational effect on claim 15)
By providing the first air blowing means and the control means that can be blown backward and forward, the temperature control of the active heating / cooling and the cooling of the light source can be performed with few air blowing means.

  Each of the above-described embodiments is a preferred embodiment of the present invention, and various modifications can be made without departing from the scope of the present invention.

It is explanatory drawing regarding the temperature control which is not warmed of the 1st Embodiment of this invention. It is explanatory drawing regarding the temperature control which warms of the 1st Embodiment of this invention. It is explanatory drawing regarding the temperature control which warms of the 1st Embodiment of this invention. It is a schematic explanatory drawing regarding temperature control using the control means 15 of the 1st Embodiment of this invention. It is explanatory drawing regarding the branch angle of the duct of the 1st Embodiment of this invention. It is explanatory drawing regarding the cross-sectional area of the branch part of the duct of the 1st Embodiment of this invention. It is explanatory drawing regarding the ventilation resistance of the duct of the 1st Embodiment of this invention. It is a schematic explanatory drawing regarding temperature control using the control means 15 of the 2nd Embodiment of this invention. It is explanatory drawing regarding the temperature control which is not warmed of the 2nd Embodiment of this invention. It is explanatory drawing regarding the temperature control which warms of the 2nd Embodiment of this invention. It is explanatory drawing regarding the temperature control which cools of the 2nd Embodiment of this invention. It is explanatory drawing regarding the temperature control which cools of the 4th Embodiment of this invention. It is explanatory drawing regarding the temperature control which cools of the 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Opening part 2 Lamp 3, 7 Fan 4, 5, 6 Duct 8 1 Display element 9 Light deflection element 15 Control means

Claims (15)

In an image projection apparatus that projects light from a light source onto a display element, and enlarges and projects a display image of the display element onto a screen by a projection lens.
The image projection apparatus includes a plurality of openings communicating with outside air, one or more internal temperature sensors installed in the display element or a place having a substitute characteristic thereof, and a duct having a branching structure to cool a light source. And a first blowing means for blowing air warmed by the light source is provided in the duct between the light source and the branch of the duct, and the first branch duct, which is one of the branched branches, is provided in the first branch duct. A second blowing unit for blowing part or all of the air blown by one blowing unit to the display element, a control unit for controlling the operation of the first and second blowing units, According to the condition of the light source and the measured value of the internal temperature sensor, the temperature change of the display element is controlled within a certain range by controlling the operation of the first and second blowing means by the control means. Images Cum apparatus. In an image projection apparatus that projects light from a light source onto a display element, and displays a display image of the display element through a light deflection element, and enlarges and projects onto a screen by a projection lens.
The image projection device includes a plurality of openings communicating with outside air, one or more internal temperature sensors installed in the light deflection element or a place having a substitute characteristic thereof, a duct having a branching structure, and a light source. The first branch duct, which is one of the branched ducts, is provided with a first blowing means for cooling and blowing the air warmed by the light source in the duct between the light source and the branch of the duct. Control means for controlling the operation of the first and second blowing means, comprising second blowing means for blowing part or all of the air blown by the first blowing means to the light deflection element. The temperature change of the light deflection element is controlled within a certain range by controlling the operation of the first and second blowing means by the control means according to the condition of the light source and the measured value of the internal temperature sensor. Features Image projection apparatus. In an image projection apparatus that projects light from a light source onto a display element, and displays a display image of the display element through a light deflection element, and enlarges and projects onto a screen by a projection lens.
A plurality of openings that communicate with the outside air in the image projection device, one or more internal temperature sensors installed in the light deflection element and the display element or a place having the substitute characteristics thereof, and a duct having a branching structure. A first branch that is one of the branched ducts, provided with a first blowing means for cooling the light source and blowing air warmed by the light source in the duct between the light source and the branch of the duct The duct is provided with second blowing means for blowing a part or all of the air blown by the first blowing means to the light deflecting element and the display element, and the first and second blowing means are provided. And controlling the operation of the first and second air blowing means by the control means according to the condition of the light source and the measured value of the internal temperature sensor. display Image projection apparatus characterized by controlling the temperature variation of the child within a certain range.   The first branch duct is installed at a lower position than the other branched ducts, and the first blowing means operates, and the total pressure when the second blowing means stops is the other branched ducts. The image projection apparatus according to claim 1, further comprising a lower structure.   5. The image projection apparatus according to claim 1, wherein a branch angle from the duct to the first branch duct is made larger than that of the other branched branch.   6. The image projection apparatus according to claim 1, wherein a cross-sectional area of the first branch duct is made smaller than that of the other branched duct.   6. The image projection apparatus according to claim 1, wherein the ventilation resistance of the first branch duct is made larger than that of the other branched duct by providing the second blowing means. .   The image projection apparatus according to claim 1, wherein the duct connects the opening of the image projection apparatus from the light source and includes a flow path.   The first and second air blowing means control ON / OFF of the operation by the control means according to the condition of the light source and the measured value of the internal temperature sensor. An image projection apparatus according to claim 1.   9. The image projection apparatus according to claim 1, wherein the second blowing unit controls the number of rotations by the control unit in accordance with a measurement value of the internal temperature sensor.   The said 1st ventilation means controls the rotation speed by the said control means according to the condition of a light source, the measured value of the said internal temperature sensor, and the operation | movement condition of a 2nd ventilation means. The image projection apparatus according to any one of 8 and 10.   The image according to any one of claims 1 to 11, further comprising a third air blowing means for cooling one or both of the light deflection element and the display element in the image projection apparatus. Projection device.   13. The image projection apparatus according to claim 1, wherein the third air blowing unit controls ON / OFF of the operation by the control unit in accordance with a measurement value of the internal temperature sensor. .   13. The image projection apparatus according to claim 1, wherein the third blowing unit controls the number of rotations by the control unit according to a measurement value of the internal temperature sensor.   The image projection apparatus according to claim 1, further comprising the first air blowing unit and the control unit that are capable of blowing air in the reverse direction.

Images