JP2005156748A - Projection-type image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid generation of fluctuations in projected images due to high-temperature exhaust, in a projection type image display device. <P>SOLUTION: The image projection device, which projects light and displays an image on a projected surface, is covered with a casing cover. A predetermined surface of the casing cover 8(2) is provided with an opening 6 for intake for introducing the air from the outside of the casing cover, an opening 9 for evacuation for evacuating the air from the inside of the casing cover and guide members 8a, 11a for evacuation for controlling the evacuating direction of the air evacuated via the opening for evacuation so as to avoid an optical path space of the projected light. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a projection type image display device such as a projector for projecting and displaying an image, and more particularly to intake and exhaust of the projection type image display device.

  In the housing of the projection type image display device, the light source and the light from the light source are color-separated and guided to an image forming element such as a liquid crystal panel, and the light modulated by the image forming element is color-synthesized, and further the screen An optical system or the like for projecting is housed. In addition, in order to cool a light source that becomes a heat source, some optical elements included in the optical system, and an electric circuit such as a power source, an air inlet and an exhaust port are provided in the housing, and forced cooling using a fan or the like A system is provided.

  For example, in Patent Documents 1 to 4, a projector that exhausts air heated by a heat source in a housing to the front side of the projector, that is, to the optical path space side until the projection light emitted from the projection lens reaches the screen. Is disclosed. By adopting a configuration that exhausts air to the front of the projector, it is possible to prevent high temperature exhaust air from being blown to viewers who are often located on the side or rear of the projector.

In addition, there is a possibility that light generated inside the housing leaks out by forming the air inlet and the air outlet in the housing. Therefore, in the projector proposed in Patent Document 1, a louver-like light shielding structure that suppresses light leakage is provided at an air inlet provided on the upper surface of the housing.
JP 2001-159783 A (paragraphs 0089 to 0092, FIG. 11 etc.) JP 2001-215615 A (paragraphs 0073-0074, FIG. 13 etc.) Japanese Patent Laid-Open No. 11-354963 (paragraphs 0013 to 0016, FIGS. 1 to 4 etc.) Japanese Patent Laid-Open No. 10-221779 (paragraphs 0024 to 0033, FIG. 1, etc.)

  However, in the projectors of Patent Documents 1 and 2 described above, since the exhausted air is high temperature, if this high temperature air enters the optical path space of the projection light from the projection lens to the screen, Since the air in the optical path space fluctuates, the projection image also fluctuates.

  In addition, some projectors have an intake port and an exhaust port disposed adjacent to each other. In this case, if the air intake direction and the exhaust direction are not controlled, the projector is once exhausted. There is a possibility that the high-temperature air is sucked into the projector again and the cooling efficiency is lowered.

  Furthermore, as in Patent Document 1, when there are gaps between a plurality of louver-like members provided as light shielding members, it is possible to effectively block until the user feels dazzled by the light leaking from the gaps. Can not.

  According to the present invention, high-temperature exhaust from the housing is not blown to the viewer, and once exhausted air is re-intaken, the cooling efficiency does not decrease, and the exhaust causes fluctuations in the projected image. It is an object of the present invention to provide a projection type image display apparatus that can avoid this.

  In order to achieve the above object, a first aspect of the present invention is an image projection apparatus that projects light and displays an image on a projection surface, which is covered with a housing cover, and the housing Avoid an intake opening formed on a predetermined surface of the cover for introducing air from the outside of the housing cover, an exhaust opening for discharging air from the inside of the housing cover, and an optical path space of the projection light. And an exhaust guide member for controlling the exhaust direction of the air exhausted through the exhaust opening.

  According to a second aspect of the present invention, there is provided an image projection apparatus covered with a housing cover, a light source housed inside the housing cover, a fan for sending air for cooling the light source, and the housing An intake opening for introducing air from the outside of the cover and an exhaust opening for discharging air from the inside of the housing cover are provided. Then, the air after cooling the light source inside the housing cover is mixed with the air introduced through the intake opening, and the mixed air is discharged outside the housing cover through the exhaust opening.

  According to the first aspect, the exhaust direction is controlled outside the optical path space of the projection light by the exhaust guide member, so that it is ensured that the high-temperature exhaust enters the optical path space and the fluctuation is generated in the projection image. Can be avoided.

  Furthermore, by forming the exhaust opening at a position farther from the projection light emitting portion than the intake opening, it can be directed outside the optical path space of the projection light without tilting the exhaust direction too much, It can also be avoided that the exhaust air is blown to the viewer located on the side of the apparatus.

  Further, by making the intake guide member and the exhaust guide member face in directions that are not parallel (different), it is possible to avoid that the high-temperature air once exhausted is sucked again and the cooling efficiency in the housing is lowered.

  Further, by shifting the position of each step of the guide member having a plurality of steps in the in-plane direction of the opening, it is possible to avoid the leakage light from the opening being visually recognized by the user who is facing the opening. Can do.

  In addition, according to the second aspect, since the outside air is mixed with the air after cooling the light source, and the temperature is lowered before exhausting, the viewer can be blown out by high temperature exhaust or projected by high temperature exhaust. It is possible to avoid fluctuations in the image. This also increases the degree of freedom in the exhaust direction.

  In addition, by forming a flow path of the air that has cooled the light source with the guide member and supplying the outside air to be mixed into the flow path, it is possible to prevent high-temperature air from spreading into the housing and The mixing efficiency, that is, the exhaust temperature lowering efficiency can be improved.

  Embodiments of the present invention will be described below with reference to the drawings.

  Hereinafter, a projector (projection-type image display device) that is Embodiment 1 of the present invention will be described. FIG. 1 shows the appearance of the projector. The projector here includes a transmissive liquid crystal projector and a reflective liquid crystal projector.

  In FIG. 1, reference numeral 1 denotes a projector, and reference numeral 2 denotes a casing that is an exterior member of the projector 5. Reference numeral 8 denotes a front cover that constitutes the front surface of the housing 2, that is, the exterior surface on the emission surface (projection light emission portion) side of the projection lens 7. In the housing 2, a light source optical system using a light source such as a discharge lamp, an image forming element for RGB 3 channels (liquid crystal panel, etc.), color separation of light from the light source is led to the image forming element, and the image forming element A color separation / synthesis optical system (not shown above) for color-combining the light modulated by the projection lens 7 and a projection lens 7 for projecting the color-synthesized light onto the screen are housed. Note that the exit surface of the projection lens 7 is exposed to the outside from the front surface of the front cover 2.

  Further, an electric circuit (not shown) such as a driving circuit for driving the power supply circuit and the image forming element is also arranged in the housing 2. An image information supply device such as a personal computer, a DVD player, a video camera, or a digital still camera (not shown) is connected to the drive circuit. The drive circuit drives the image forming element in accordance with the image signal from the image information supply device. As a result, an image corresponding to the image signal is enlarged and projected onto the screen.

  At a position adjacent to the projection lens 7 on the front surface of the front cover 8, the optical system housed in the housing 2, in particular, a light source serving as a heat source and outside air for cooling the optical elements are introduced into the housing 2. An intake port 6 is formed.

  Further, an exhaust port 9 through which high-temperature air (exhaust) 14 used for cooling the inside of the housing 2 is discharged is formed on the front surface of the front cover 8 on the side of the intake port 6.

  FIG. 2 shows a peripheral configuration of the intake / exhaust port in the present embodiment. An exhaust fan 12 for forced exhaust is held by a fan holder 11 at a position facing the exhaust port 9 inside the housing 2 (front cover 8). The fan holder 11 is provided with a later-described louver 11a integrally or separately.

  Here, FIG. 4 shows a structure around an exhaust port in a conventional projector. Note that the intake port is omitted.

  The projection light emitted from the projection lens 7 passes through the optical path space 10 and reaches a screen (not shown). This optical path space 10 has an expansion angle with respect to the optical axis 40 of the projection lens 7.

  The air heated by the heat source in the housing 2 is forcibly exhausted to the outside by the exhaust fan 12. The front surface of the front cover 8 is punched. When exhaust is made through a large number of holes (exhaust ports) 8c in the punched portion, the flow of the exhaust 14 is disturbed. When a part of the disturbed exhaust 14 enters the optical path space 10, the air in the optical path space 10 fluctuates, and as a result, the projected image on the screen also fluctuates.

  On the other hand, in this embodiment, as shown in FIG. 2, the flow direction (exhaust direction) of the air exhausted from the exhaust port 9 to the outside is provided in the exhaust port 9 of the fan holder 11 and the front cover 8. The air flow is rectified by a plurality of louvers (exhaust guide members) 11 a and 8 a that are plate-like members, and the exhaust direction is controlled (oriented) so as to be out of the optical path space 10. Therefore, compared with the case shown in FIG. 4, the possibility that the exhaust 14 forcedly exhausted by the fan 12 enters the optical path space 10 of the projected light is greatly reduced, and the occurrence of fluctuations in the projected image can be prevented. It becomes.

  In this embodiment, FIG. 3 shows the relationship between the angle of the louver 11a and the projection angle of the projection light. Although only the louver 11a is shown in the drawing, the same relationship holds for the louver 8a.

The angle of the louver 11a (hereinafter referred to as the louver angle) θ _{G with} respect to the optical axis 40 of the projection lens 7 (that is, the projection light) is the emission angle (half angle of view) of the projection light emitted from the projection lens 7 with respect to the optical axis 40. ) Is θ _P , L is the projection distance to the screen 16, and W is the width of the projected image 17 on the screen 16 in the louver angle direction.
θ _G > θ _P (1)
θ _P = tan ₋₁ (W / 2 / L) (2)
Is set to satisfy.

For example, assuming that the projection distance L is 4000 mm, the projected image on the screen 16 is 100 inches in size (diagonal 2540 mm), and the width W is 2800 mm, the emission angle θ _P of the projection light is
tan ₋₁ {(2800/2) / 4000} = 19.29 °
Thus, the louver angle θ _G is set to be larger than at least 19.29 °.

  By setting the louver angle so as to satisfy the above conditions (1) and (2), it is possible to prevent the exhaust image from entering the optical path space 10 of the projection light and shaking the projection image.

  Here, as shown in FIG. 7, when the exhaust port 9 is provided on the back surface of the light source (lamp) 24, when the user 22 views the exhaust port 9 directly between the louvers 11 a and 8 a. If there is a gap, part of the light generated by the light source 24 leaks out of the gap and the user 22 feels very dazzling.

  Therefore, in this embodiment, as shown in FIG. 5, the relationship between two adjacent louvers among the plurality of louvers 11a and 8a is set as follows. In FIG. 5, P is the louver pitch (interval).

In FIG. 5, one of the two exhaust louvers adjacent to the exhaust upstream end 39 and the other exhaust downstream end 38 faces the exhaust port 9 from the direction indicated by the white arrow in the figure. When viewed, they overlap each other. Exhaust direction length L _G of the louvers to satisfy this relationship is determined by the louver angle theta _G and louver pitch P, it becomes larger the higher the louver angle theta _G is small or louver pitch P longer.

For this reason, for example, as shown in FIG. 6, when it is desired to set the louver angle θ _G as small as possible (if the louver angle is increased too much, there is a possibility that a part of the exhaust may be applied to the viewer on the side of the projector. In the case), the length L _G of the louver in the exhaust direction can be suppressed by increasing the number of louvers and decreasing the pitch P of the louvers.

  Furthermore, in this embodiment, as shown in FIG. 2, the intake port 6 and the exhaust port 9 are formed so as to be adjacent to the front cover 8. It is formed at a position away from 6.

  As described above, the exhaust 14 forcedly exhausted by the exhaust fan 12 is guided to the inside of the exhaust port 9 of the front cover 8 and the exhaust fan 12 in a direction away from the projection lens 7 (in other words, in other words). For example, louvers 8a and 11a are provided in which the exhaust direction is a direction away from the optical path space 10 of the projection light.

  On the other hand, a louver 8b is formed on the inner side of the intake port 6 of the front cover 8 so as to face the exhaust louvers 8a and 11a. By setting the direction of the louver 8b in this way, outside air is introduced into the intake port 6 from the optical path space 10 side of the projection light. For this reason, the possibility that the exhaust 14 discharged in the direction away from the projection lens 7 side is sucked from the intake port 6 adjacent to the exhaust port 9 is reduced, and the outside air sucked from the intake port 6 is always exhausted. The temperature is lower than 14. For this reason, the cooling efficiency in the housing | casing 2 can always be maintained favorable.

  FIG. 8 shows a structure around an exhaust port of a projector that is Embodiment 2 of the present invention. In this embodiment, the front cover 8 and the fan holder 11 are molded using a plastic material such as ABS resin.

  In FIG. 8, louvers 8a and 11a having substantially the same shape and size are formed inside the exhaust port 9 of the front cover 8 and the fan holder 11, respectively, and these are in the exhaust direction (direction perpendicular to the opening surface of the exhaust port). The case where it becomes an exhaust guide of 2 steps | paragraphs is shown.

  The louvers 8a and 11a can be integrally formed with the front cover 8 and the fan holder 11 by using, for example, a louver molding die 27 including a first die 28 and a second die 29 shown in FIG. In this case, a plurality of louvers spaced from each other can be formed by providing, for example, 0.2 mm or more of the portion 30 where the first mold 28 and the second mold 29 overlap.

  However, in each of the front cover 8 and the fan holder 11, as shown in FIG. 10 (only the front cover 8 is shown in the figure), a gap 30 is provided between adjacent louvers by the amount of the overlap portion. When the user 31 looks directly at the exhaust port 9, the leaked light 23 enters the eyes.

  Therefore, in this embodiment, as shown in FIG. 8, the louver (first stage) 8a provided in the exhaust port 9 of the front cover 8 and the louver (second stage) 11a provided in the fan holder 11 are exhausted. They are provided at different positions (shifted positions) in the in-plane direction of the opening 9 (in other words, the arrangement direction of the louvers in each of the front cover 8 and the fan holder 11). Specifically, in order to block the leaked light in the facing direction while ensuring the ventilation function as an exhaust port, the amount of deviation between the louvers 8a and 11a is approximately half the arrangement pitch of the louver-shaped portions. Yes. Thereby, both louvers 8a and 11a are alternately arranged in the arrangement direction thereof.

  As a result, the gap 30 between the louvers 8 a provided in the front cover 8 when the exhaust port 9 is viewed directly is covered by the louvers 11 a provided in the fan holder 11. Therefore, it is possible to effectively block the leaked light from the gap 30 generated in FIG.

  Further, since the side surface (exhaust guide surface) of the louver 8a provided on the front cover 8 and the side surface of the louver 11a provided on the fan holder 11 are substantially parallel to each other, the flow direction of the exhaust gas is made constant. It is possible to control.

  Note that the louver shading structure as described in the present embodiment may also be adopted in the intake port 6.

  FIGS. 11 and 12 respectively show the external appearance and internal configuration of a projector that is Embodiment 3 of the present invention. In addition, the same code | symbol as Example 1 is attached | subjected about the component which is common in Example 1. FIG.

  In FIG. 11, 3 is an operation panel on which switches for performing basic operations such as turning on / off the power of the projector 51 and adjusting an image projected on the screen are arranged. Reference numeral 18 denotes an adjuster for adjusting the position of the projector 51 in the height direction.

  In FIG. 12, 24 is a discharge lamp (light source) such as a mercury lamp, and 4 is a color separation of light from the discharge lamp 24 and three color light components modulated by an RGB three-channel image forming element. This is an optical system that leads to the projection lens 7. These are accommodated in a housing 2 having a front cover 8 disposed on the front surface.

  Reference numeral 54 denotes a cooling fan that generates an air flow for cooling the discharge lamp 24 in the housing 2. The air flow 56 generated by the cooling fan 54 absorbs heat from the discharge lamp 24 and cools it, and is then discharged to the outside from the exhaust port 9 formed in the front cover 8. An intake / exhaust flow path is formed by the guide plates 52 and 53 from the cooling fan 54 to the exhaust port 9 in the housing 2. This prevents the air flow (warm air) 56 that has cooled the discharge lamp 24 from spreading into other spaces in the housing 2. A louver 8a similar to that described in the first embodiment is formed inside the exhaust port 9, and the exhaust 58 is discharged in a direction away from the optical path space 10 of the projection light.

  Further, a suction port 5 different from the suction port 6 formed in the front cover 8 is formed on the side surface of the housing 2. A plurality of louvers 2 a facing obliquely rearward are arranged inside the intake port 5 so that the exhaust 58 from the exhaust port 9 is not taken in again through the intake port 5.

  An intake fan 55 that forcibly introduces outside air into the housing 2 through the intake port 5 is provided at a position facing the intake port 5 in the housing 2. The outside air 57 introduced by the intake fan 55 is supplied to a portion closer to the exhaust port 9 than the discharge lamp 24 in the intake / exhaust flow path formed by the guide plates 52 and 53. Therefore, the outside air 57 is mixed with the air flow (warm air) 56 generated by the cooling fan 54 and cooling the discharge lamp 24. Therefore, the temperature of the exhaust from the exhaust port 9 can be made lower than when the outside air 57 is not mixed. In addition, by supplying the outside air into the intake / exhaust flow path, the mixing efficiency of the outside air with respect to the warm air 56, that is, the exhaust temperature lowering efficiency can be improved.

  By reducing the exhaust temperature in this way, in addition to the effects of the first embodiment, even if the exhaust is blown to the user or the viewer, there is no need to give unpleasant feeling.

  However, since the exhaust temperature is lowered, even if the exhaust enters the optical path space 10 of the projection light without providing the louver 8a at the exhaust port 9, the projection image hardly fluctuates. However, in order to avoid exhausting the exhaust air again from the intake port 6, it is better to provide a louver 8a.

  FIGS. 13 and 14 respectively show the external appearance and internal configuration of a projector that is Embodiment 4 of the present invention. In addition, the same code | symbol as this Example is attached | subjected to the component which is common in the Example mentioned above. FIG. 14 mainly shows the cooling structure of the discharge lamp 24 of the projector 71 placed on the table.

  An intake port 74, an exhaust guide 72 that controls the direction of the exhaust gas 86, and a flow direction of the outside air 85 toward the intake port 74 are arranged on the bottom surface of the housing 2 of the projector 71 from the side surface side of the housing 2. An intake guide 73 extending toward the port 74 and a wall 75 for preventing the exhaust gas 86 from being sucked into the intake port 74 again are provided.

  In FIG. 2, the outside air 84 sucked into the housing 2 by the axial fan 76 from the air inlet 78 formed on the back surface of the housing 2 cools the discharge lamp 24 and becomes hot air 87. The hot air 87 is sucked from the upper surface suction port 77 a of the double-sided intake type radial fan 77. Around the discharge lamp 24, an intake / exhaust flow path for guiding the warm air 87 to the upper surface inlet 77 a of the radial fan 77 is formed by a lamp housing 79 formed so as to surround the discharge lamp 24.

  On the other hand, outside air 85 is sucked from the lower surface inlet 77 b of the double-sided intake type radial fan 77 through the inlet 74 formed on the bottom surface of the housing 2. Inside the radial fan 77, the warm air 87 and the outside air 85 are mixed, and the mixed air 86 has a temperature lower than that of the warm air 87. Then, the mixed air 86 is exhausted through a discharge port 72 and an exhaust guide 72 of the radial fan 77 into a gap formed between the bottom surface of the housing 2 and the table on which the projector 71 is placed by the adjuster 18. The

  Although the exhaust temperature is sufficiently low due to the mixing of the outside air, the exhaust direction is further controlled by the exhaust guide 20 to prevent the table surface from being heated by the exhaust.

  In the present embodiment, the flow passage cross-sectional area of the exhaust guide 72 is gradually increased from the discharge port 77 c side to the outlet side of the radial fan 77. As a result, the exhaust gas 86 discharged from the radial fan 77 can be discharged at a reduced flow rate.

  Further, in the present embodiment, since the outside air is controlled by the intake guide 73 so as to flow in a certain direction toward the intake port 74, turbulence that is a main cause of airflow noise is less likely to occur, and noise reduction can be achieved. .

  FIG. 15 shows a state in which the above-described double-sided intake radial fan 77 is viewed obliquely from below, and FIG. 16 shows an axial fan 76. Further, FIG. 17 shows a state in which the discharge lamp 24 is attached to the guide member 79 and the double-side intake radial fan 77 and the axial fan 76 are attached to the guide member 79 to form a lamp unit.

  The double-sided intake radial fan 77 is provided with suction ports 77a and 77b on both sides in the rotational axis direction of the fan, and a discharge port 77c in the radial direction of the fan.

  The axial fan 76 includes a suction port 76a and a discharge port 76b in the direction of the rotation axis of the fan.

  Further, in the lamp unit shown in FIG. 17, the intake / exhaust flow path is formed in the lamp housing 79 that prevents the heat originally generated by the lamp 24 from being transmitted to other areas in the housing 2. Cooling can be performed efficiently.

  In general, the axial fan 76 has characteristics such as a large air volume and a small static pressure. For this reason, in this embodiment, the lamp 24 can be efficiently cooled by directing the discharge port 76b of the axial fan 76 toward the lamp 24 and blowing a large amount of cooling air onto the lamp 24.

  Then, when exhausted from the inside of the lamp housing 79 to the outside, the double-sided intake radial fan 9 is used to suck in the air heated and remained in the lamp housing 79 from the upper surface intake port 77a. After cooling (mixing the outside air) with the outside air sucked from the port 77b, the air is finally exhausted to the outside through the discharge port 77c and the exhaust guide 72. Thereby, since the air heated in the housing | casing 2 is not discharged | emitted outside as it is, the user to whom this exhaust_gas | exhaustion was sprayed hardly feels discomfort.

  FIG. 18 shows a configuration around an exhaust guide of a projector that is Embodiment 5 of the present invention. The present embodiment is a modification of the fourth embodiment.

  In the fourth embodiment, the exhaust guide 72 is fixed with respect to the housing 2. However, in this embodiment, the exhaust guide 72 can be rotated by a shaft member 72 a supported by the housing 2. As shown in practice, it can be set at a position stored in the housing 2 (closed position) and a position protruding below the housing 2 (open position) as shown by a dotted line.

  When the projector 71 is used, the exhaust guide 72 is moved down to the open position to secure the exhaust path. On the other hand, when the projector 71 is not used, the exhaust guide 72 is moved up to the closed position, and an air filter or the like is provided to prevent foreign matters such as dust and dirt from entering the double-sided intake radial fan 77 from the outside. Prevent without.

  In this case, the exhaust guide 72 may be urged by a spring or the like in the open position direction, and a lock mechanism that locks and holds the exhaust guide 72 in the closed position may be provided. Then, as shown in FIG. 19, by operating the release button 91 provided on the bottom surface of the housing 2, the lock holding by the lock mechanism is released, and the exhaust guide 72 is driven to the open position. .

  It is to be noted that by providing a plurality of exhaust guides 72 having different facing directions so that only the exhaust guide 72 to be used can be set in the open position, the exhaust direction can be freely selected according to the usage situation of the projector 71. Can do.

  Further, the exhaust guide 72 may be detachable from the housing 2.

  Further, in the fourth embodiment, the case where the wall portion 75 is provided in the vicinity of the intake port 74 on the bottom surface of the housing 2 is described so that the exhaust from the exhaust guide 72 is not sucked into the intake port 74 again. As shown in FIG. 19, the wall portion 75 may be foldable with respect to the bottom surface of the housing 2.

  In this case, when the projector 71 is used, the wall portion 75 may be raised by hooking a finger on the knob 92.

  FIG. 20 shows a configuration around an exhaust guide of a projector that is Embodiment 6 of the present invention. The present embodiment is a modification of the fourth embodiment.

  In the fourth embodiment, the case where the intake guide 73 provided on the bottom surface of the housing 2 is shaped to extend from the side surface side of the housing 2 toward the intake port 74 has been described. In addition, it is formed by minute projections (Vortex Generator) 73 ′ arranged so that no peeling state occurs in the airflow.

  As a result, the outside air is controlled to flow more effectively toward the intake port 74.

  FIG. 21 shows the configuration around the exhaust guide of a projector that is Embodiment 7 of the present invention. The present embodiment is a modification of the fourth embodiment.

  In the present embodiment, the radiating fins 72b formed of a member having excellent heat conduction performance are provided inside the exhaust guide 72 (flow path). Thereby, even when the temperature of the exhaust gas (mixed air with the outside air) 86 discharged from the double-sided intake type radial fan 77 does not become sufficiently low just by mixing the outside air, the exhaust gas 86 passes through the exhaust guide 20 in the process. Heat is further deprived by the radiating fins 72b, resulting in exhaust at a sufficiently low temperature.

  The exhaust guide 72 itself may be formed of a member having excellent heat conduction performance so as to absorb the heat from the radiation fins 72b.

  FIG. 22 shows an internal configuration of a projector that is Embodiment 8 of the present invention. In the fourth embodiment, the case where the air discharged from the double-sided intake type radial fan 77 (mixed air 86 with outside air) is exhausted to the outside as it is, but in this embodiment, the mixed air 86 is put into the housing 2. It is discharged into the housing 2 through the installed exhaust guide 72 and used to cool other heat sources. Then, the temperature of the mixed air 86 raised thereby is lowered again by the heat radiating fins 95 provided in the housing 2, and finally passed through a front cover that has been punched by a fan (radial or axial fan) 96. Exhaust outside (86 ').

  Thus, the air taken into the housing 2 to be used for cooling the lamp 24 can be used not only for cooling the lamp 24 but also for cooling various heat sources in the housing 2.

  Note that FIG. 22 is a side view only, and the mixed gas 86 ′ exhausted from the front cover flows away from the optical path space of the projection light when viewed from above.

1 is an external view of a projector that is Embodiment 1 of the present invention. FIG. FIG. 3 is a schematic diagram illustrating an intake / exhaust structure of the projector according to the first embodiment. FIG. 3 is a schematic diagram illustrating a condition of a louver angle of the projector according to the first embodiment. FIG. 10 is a schematic diagram showing an exhaust structure of a conventional projector. FIG. 3 is a schematic diagram illustrating a light shielding condition by a louver of the projector according to the first embodiment. FIG. 3 is a schematic diagram illustrating a light shielding condition by a louver of the projector according to the first embodiment. FIG. 6 is a schematic diagram showing light leaked from an exhaust port of a conventional projector. FIG. 6 is a schematic diagram showing a light shielding structure by a louver shape portion in a projector that is Embodiment 2 of the present invention. The figure which shows the type | mold for shape | molding the louver shape part used in Example 2. FIG. FIG. 6 is a schematic diagram showing light leaked from an exhaust port of a conventional projector. FIG. 6 is an external view of a projector that is Embodiment 3 of the present invention. FIG. 6 is a schematic diagram illustrating an intake / exhaust structure of a projector according to a third embodiment. FIG. 6 is an external view of a projector that is Embodiment 4 of the present invention. FIG. 6 is a schematic diagram illustrating an intake / exhaust structure of a projector according to a fourth embodiment. FIG. 6 is an external view of a double-sided intake radial fan used in Example 4. FIG. 6 is an external view of an axial fan used in Example 4. FIG. 6 is an external view of a lamp unit used in Example 4. FIG. 10 is a schematic diagram illustrating an exhaust structure of a projector that is Embodiment 5 of the present invention. FIG. 10 is an external view of a projector that is a modification of the fifth embodiment of the present invention. FIG. 10 is an external view of a projector that is Embodiment 6 of the present invention. FIG. 10 is a schematic diagram showing an exhaust structure of a projector that is Embodiment 7 of the present invention. FIG. 10 is a schematic diagram showing an intake / exhaust structure of a projector that is Embodiment 8 of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,51,71 Projector 2 Case 5,6 Intake port 7 Projection lens 8 Front cover 8a, 8b Louver 9 Exhaust port 10 Optical path space of projection light 11 Fan holder 11a Louver 12 Fan 15 Projection image 16 Screen 18 Adjuster 23 Leakage light 24 Light source (discharge lamp)
27 Louver molding mold 28, 29 mold 30 Clearance 40 Optical axis of projection lens (projection light) 72 Exhaust guide 72b Radiation fin 73 Intake guide 74 Inlet port 75 Wall portion 76 Axial fan 77 Double-sided intake type radial fan 79 Lamp housing

Claims (11)

An image projection apparatus that projects light and displays an image on a projection surface, which is covered with a housing cover,
An intake opening for introducing air from the outside of the housing cover and an exhaust opening for discharging air from the inside of the housing cover, formed on a predetermined surface of the housing cover;
An image projection apparatus comprising: an exhaust guide member that controls an exhaust direction of air exhausted through the exhaust opening so as to avoid an optical path space of projection light. The angle θ _G formed by the exhaust guide member with respect to the optical axis of the projection light is θ _{P as} the emission angle of the projection light with respect to the projection optical axis, and W is the size of the projection image in the direction of the emission angle. When the distance is L,
θ _G > θ _P
θ _P = tan ₋₁ (W / 2 / L)
The image projection apparatus according to claim 1, wherein the following condition is satisfied.   The image projection apparatus according to claim 1, wherein the exhaust opening is formed at a position away from the intake opening with respect to the projection light emitting portion. An intake guide member for controlling an intake direction of air introduced through the intake opening;
4. The image projection apparatus according to claim 1, wherein an intake direction of the intake guide member is not parallel to an exhaust direction of the exhaust guide member. 5.   The image projection apparatus according to claim 4, wherein an intake direction by the intake guide member is substantially perpendicular to an exhaust direction by the exhaust guide member. The exhaust guide member has a plurality of guide members in a direction perpendicular to the exhaust opening surface,
The first-stage guide member and the second-stage guide member are arranged so as to be shifted from each other by a predetermined amount in the in-plane direction of the exhaust opening. Image projection device. A light source housed inside the housing cover;
A second intake opening for introducing air from outside the housing cover;
The light source is cooled by air introduced from the outside of the housing cover through the intake opening, and the air after cooling the light source inside the housing cover and the second air intake opening are introduced. The image projection apparatus according to claim 1, wherein the mixed air is discharged to the outside of the housing cover through the exhaust opening.   The image projection apparatus according to claim 7, wherein the second intake opening is formed on a surface different from a predetermined surface of the housing cover. An image projection apparatus covered with a housing cover,
A light source housed inside the housing cover;
A fan for sending air to cool the light source;
An intake opening for introducing air from outside the housing cover;
An exhaust opening for exhausting air from the inside of the housing cover,
The air after cooling the light source inside the housing cover is mixed with the air introduced through the intake opening, and the mixed air is discharged outside the housing cover through the exhaust opening. An image projection apparatus characterized by:   The image projection apparatus according to claim 9, wherein both the intake opening and the exhaust opening are formed on a predetermined surface of the housing cover. The image projection apparatus according to claim 1 or 10,
An image information supply device that supplies image information to the image projection device.

Images