JP2008191532A - Rear projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rear projector capable of completing its correspondence including dust removal at a customer site. <P>SOLUTION: The rear projector 1 modulates light rays emitted from a light source according to image information and diverges and projects the light rays onto a screen 20. The rear projector has in the sides 16 of its outer package 10 an intake part 30a having an intake filter and intake port cover 32 and an exhaust part 30b having an exhaust filter and an exhaust port cover 36. Dust in the outer package 10 is removed such that the intake port cover and exhaust port cover 36 are detached and air in the outer package 10 is forcibly expelled by a dust collector 60 connected to the hose attaching section of the exhaust part 30b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rear projector provided with dust removal means.

  Conventionally, in rear projectors, dust that has entered with cooling air taken in from the outside or dust that has adhered to the light path floats in the light path from the light source to the screen due to the flow of cooling air. , Sometimes projected on the screen together with the video. For this reason, as a method for preventing the intrusion of dust, a cooling mechanism is disclosed in which cooling air is blocked from the outside and the cooling air is circulated inside the rear projector (for example, Patent Document 1).

JP 2006-72138 A

  However, in the conventional technology, when inspecting or repairing the interior of the rear projector for after-sales service, etc., it is necessary to bring it back from the customer and work in a clean room to ensure the cleanliness of the interior of the rear projector. was there. This is because it is difficult for a rear projector provided with a cooling mechanism for circulating cooling air to reliably remove dust from the interior of the rear projector after inspection or repair. Therefore, since even simple inspections can be carried out, it has been desired to improve the service to customers.

  In order to solve the above-described problems, an object of the present invention is to provide a rear projector in which a correspondence including dust removal work is completed at a customer site.

  The rear projector of the present invention modulates a light beam emitted from a light source according to image information, and enlarges and projects an optical unit, a housing that houses the optical unit, a side surface of the housing, and projects from the optical unit. And a suction portion having an intake filter and an intake port lid, and an exhaust portion having an exhaust filter and an exhaust port lid are provided in the case. The exhaust port cover is removed, and the air inside the housing is forcibly exhausted by an exhaust device connected to the exhaust unit.

  According to this rear projector, the air in the housing is forcibly exhausted from the exhaust section, and at the same time, air that does not contain dust or the like is taken in from the intake section via the intake filter, so that the dust and the like floating in the housing are enclosed with the air. It can be removed outside the body. If dust or the like floats in the housing or dust or the like adheres to a screen or mirror, it may cause light shielding or polarization, resulting in deterioration of image quality. By providing the rear projector with an air intake unit and an exhaust unit, when dust etc. floats in the housing, it can be removed from the exhaust unit to the outside of the housing, eliminating the situation where dust etc. is projected on the screen Can be done easily. In addition, the intake and exhaust sections have an intake vent cover and an exhaust vent cover, respectively. Except during dust removal work, by attaching both covers, the intake and exhaust sections are part of the chassis. Since the casing is hermetically sealed like this, the function of the rear projector is not affected by light flux leakage or cooling air leakage. As described above, since the rear projector includes the intake unit and the exhaust unit, dust and the like inside the housing can be discharged using a cleaning device or the like at a place where the rear projector is installed. Therefore, when the rear projector is inspected or repaired, the inside of the housing after work can be cleaned on the spot without moving the rear projector to a dedicated equipment room equipped with a dust removing device.

  In this case, the intake filter preferably has a finer mesh than the exhaust filter and excludes dust that is projected on the screen so as to be visible.

  According to this configuration, the air sucked through the intake filter is substantially free of dust and the like that is projected on the screen, and the cleanliness inside the housing is restored. On the other hand, the exhaust filter has a coarser mesh than the intake filter, and serves to maintain the strength of exhausting air from the casing while removing dust and the like as much as possible outside the casing to prevent clogging. The intake filter has a fine mesh, and the exhaust filter has a coarse mesh, so that the dust inside the casing can be efficiently removed.

  In this case, it is preferable that the intake part and the exhaust part are respectively provided on opposing surfaces of the housing.

  According to this configuration, when the exhaust from the exhaust section is started, the air inside the casing is exhausted from the exhaust section provided at the other end face section opposed to the intake section provided at one end face section of the casing. And there is almost no air stagnation inside the housing. Therefore, even if dust or the like is present in the inside of the housing, it can be carried to the exhaust part together with the air flow. By such an opposing arrangement of the intake part and the exhaust part, it is possible to effectively remove dust and the like in the housing.

  The rear projector according to the present invention is provided with an optical unit that modulates and projects a luminous flux emitted from a light source according to image information, a housing that houses the optical unit, and a side surface of the housing. A cooling device that projects a light beam projected from the unit and that circulates cooling air in a sealed space inside the housing, and an exhaust gas that is provided in the housing and has an exhaust filter and an exhaust port lid And a duct that communicates between the sealed space and the exhaust part, and dust removal in the sealed space is performed by removing the exhaust port lid and forcibly exhausting the air in the sealed space with the exhaust device connected to the exhaust part. Features.

  According to this rear projector, even dust or the like floating in a sealed space inside the casing can be removed outside the casing. If dust or the like floats in the sealed space, or dust or the like adheres to the screen or mirror, it causes light shielding or polarization, leading to deterioration in image quality. By providing a duct that communicates with the sealed space and an exhaust part, when dust or the like floats inside the sealed space, dust or the like can be removed from the exhaust part to the outside of the housing together with cooling air, and the dust is projected onto the screen. It can be easily cleaned to eliminate the state that is caused. In addition, the exhaust part has an exhaust port lid and is attached to the exhaust part except during dust removal work, so that the exhaust part becomes a part of the casing and seals the casing Therefore, the function of the cooling device is not affected by cooling air leakage or the like. Thus, by providing the rear projector with the duct and the exhaust unit, dust and the like inside the housing can be discharged using a cleaning device or the like at the place where the rear projector is installed. Accordingly, in the inspection or repair of the rear projector, it is possible to clean the inside of the housing after work without moving the rear projector to a dedicated equipment room equipped with a dust removing device.

  In this case, it is preferable that the sealed space includes a light flux path.

  According to this configuration, the rear projector is provided with devices that need to be cooled along the path of the light beam, and since the sealed space includes the path of the light beam, these devices are isolated from dust and the like. It is possible to cool. In addition, the sealed space including the path of the light beam has a wider back space for enlarging and projecting the light beam onto the screen. The heat is dissipated through Therefore, even in a sealed space, the devices can be cooled by circulating cooling air. When dust removal is required, it can be easily performed by using a duct and an exhaust part communicating with the sealed space.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. The rear projector in the embodiment forms a color image from an optical image obtained by modulating light (light beam) emitted from a light source according to image information, and enlarges and projects the color image on a screen via a reflection mirror. The rear projector includes a dust removing unit that can easily remove dust and the like from the rear projector.
(Embodiment 1)

  FIG. 1 is a perspective view showing the appearance of the rear projector as seen from the front side, and FIG. 2 is a perspective view of the appearance of the rear projector as seen from the rear side and the dust removing portion. As shown in FIG. 1 and FIG. 2, an exterior (housing) 10 that forms the exterior of the rear projector 1 is in order of a leg exterior 11 that is a floor-mounted installation portion of the rear projector 1 and an upper side of the leg exterior 11. It has the lower exterior 13 and the upper exterior 12 which are located, and the front exterior 14 provided in the front side of the upper exterior 12.

  The front exterior 14 has an opening formed in a rectangular shape, and a screen 20 is attached to the opening so as to close the opening. Further, the front exterior 14 has speaker boxes 22 on the left side and the right side, respectively.

  The lower exterior 13 has a woofer box 23 that accommodates a speaker that reproduces a low frequency range on the left and right sides of the front side, and a rear cover 10a cools a light source unit, which will be described later, as shown in FIG. A light source intake port 18 and a light source exhaust port 19 for sucking and exhausting cooling air. These intake / exhaust ports will be described later with reference to FIG.

  The upper exterior 12 has a triangular shape when viewed from the side, a boundary surface portion 15 that forms a boundary with the lower exterior 13, and left and right side surface portions 16 that are triangular plates that are erected from both ends of the boundary surface portion 15, And a back surface portion 17 that is a slope straddling these left and right side surface portions 16.

  Further, the left and right side surface portions 16 are provided with circular dust removing portions 30 for removing dust and the like from the inside of the exterior 10. The dust removing unit 30 includes an intake portion 30 a provided on the right side surface portion 16 and an exhaust portion 30 b provided on the left side surface portion 16 when viewed from the back surface portion 17. As shown in the enlarged sectional view 2 attached to FIG. 2, the air intake portion 30 a covers the through hole 33 provided in the side surface portion 16 and the through hole 33 on the inner side of the rear projector 1 with respect to the through hole 33. And an intake port lid 32 that seals the through-hole 33 and is detachable from the outside of the rear projector 1. Further, as shown in the enlarged sectional view 1, the exhaust part 30 b is provided with a through hole 34 provided in the side face part 16 and an exhaust provided so as to close the through hole 34 on the inner side of the rear projector 1 with respect to the through hole 34. A filter 35, an exhaust port lid 36 that seals the through-hole 34 and is detachable from the outside of the rear projector 1, and a hose that is a step protruding from the side surface 16 to the outside of the rear projector 1 so as to extend the through-hole 34. And a mounting portion 37. Detailed functions of the dust removing unit 30 will be described later with reference to FIG.

  Next, the internal configuration of the rear projector 1 will be briefly described. FIG. 3 is a cross-sectional view showing the internal configuration of the rear projector as viewed from the side. As shown in FIG. 3, an optical unit 40 that emits light including an optical image provided on the leg exterior 11 side of the lower exterior 13 and an optical unit 40 are placed inside the rear projector 1. The adjustment mechanism 48 that adjusts the direction of light emitted from the optical system 40 and the optical unit 40 and the screen 20 are provided on the inner side of the rear surface of the upper exterior 12 so as to be emitted from the projection optical system 45 of the optical unit 40. And a reflection mirror 25 for reflecting the reflected light to the screen 20 is accommodated.

  In this configuration, since the light emitted from the optical unit 40 to the reflection mirror 25 is in a wide angle state, it travels as indicated by the light path L, and is reflected by the reflection mirror 25 and reaches the screen 20. The image is enlarged and projected on the entire surface of the screen 20. In addition to the optical unit 40 and the adjustment mechanism unit 48, the lower exterior 13 includes a power supply unit (not shown), a control unit that controls the optical unit 40, and the interior of the rear projector 1 including the optical unit 40 by cooling air. The cooling mechanism part etc. which cool are accommodated.

  FIG. 4 is a perspective view showing the external appearance of the optical unit, and is a view of the optical unit viewed from obliquely above. The optical unit 40 optically processes light emitted from a light source lamp, which is a light source, to form an optical image corresponding to image information, and a color image obtained by synthesizing the optical image is reflected on the reflection mirror 25 shown in FIG. And a unit for enlarging and projecting to the screen 20. As shown in FIG. 4, the optical unit 40 includes a light source system 46, an integrator illumination optical system 41, a color separation optical system 42, a relay optical system 43, a modulation optical system 44, and projection optics in the order of light travel. And a system 45. In this case, in the optical unit 40, the light is emitted from the light source system 46, bent, travels in the direction of the projection optical system 45, and is emitted from the projection optical system 45 toward the reflection mirror 25.

  The optical unit 40 is cooled by two cooling flows, a cooling air flow A that is a cooling air flow that mainly cools the modulation optical system 44 and a cooling air flow B that mainly cools the light source system 46. Done. The optical unit 40 is provided around the projection optical system 45 and has an intake frame 50 having an opening for taking in cooling air from above, which is the light emission direction side, and the cooling air provided at the lower part of the projection optical system 45. And a sirocco fan 52 for sucking air into the intake frame 50. The cooling air sucked into the fan intake port 52 a of the sirocco fan 52 cools the modulation optical system 44 while forming a cooling air flow A. Details of the cooling air flow A will be described later with reference to FIG.

  The optical unit 40 has a sirocco fan 53 below the light source system 46. The sirocco fan 53 draws cooling air from the light source inlet 18 shown in FIGS. 2 and 3 and blows it to the light source system 46. Thus, a cooling air flow B that is cooled and exhausted from the light source exhaust port 19 via the exhaust duct portion 54 is formed. Details of the cooling air flow B will be described later with reference to FIG.

  Next, the optical unit 40 that is the backbone of the rear projector 1 will be described in detail. FIG. 5 is a schematic view showing details of the inside of the optical unit. First, the light source system 46 will be described in order. The light source system 46 includes a light source lamp 462 that is a light source and a reflector 463 as a light source device 461, and a radial light beam emitted from the light source lamp 462 is reflected by a reflector 463 that is a parabolic mirror so as to be parallel. Ejected as light rays. In this case, a halogen lamp is used as the light source lamp 462. In addition to the halogen lamp, a metal halide lamp, a high-pressure mercury lamp, or the like may be employed.

  The integrator illumination optical system 41 is for making the illuminance distribution of light from the light source substantially uniform. Specifically, it is an optical system for illuminating the optical image forming area of the three liquid crystal panels 441 (441R, 441G, 441B) constituting the modulation optical system 44 substantially uniformly, and includes a first lens array 412, A second lens array 413, a polarization conversion element 414, and a superimposing lens 415 are provided.

  Although not shown in detail, the first lens array 412 has a configuration in which small lenses having a substantially rectangular outline as viewed from the optical axis direction are arranged in a matrix. These small lenses are for dividing the light emitted from the light source device 461 into a plurality of partial lights, and the contour shape of each small lens is substantially similar to the shape of the optical image forming region of the liquid crystal panel 441. It is set to make. For example, if the aspect ratio of the optical image formation region of the liquid crystal panel 441 (the ratio between the horizontal and vertical dimensions) is 16: 9, the aspect ratio of each small lens is also set to 16: 9.

  The second lens array 413 has substantially the same configuration as the first lens array 412, and has a configuration in which small lenses are arranged in a matrix. The second lens array 413, together with the superimposing lens 415, functions to form an optical image of each small lens of the first lens array 412 on the liquid crystal panel 441.

  The polarization conversion element 414 is disposed between the second lens array 413 and the superimposing lens 415 and is unitized with the second lens array 413. Such a polarization conversion element 414 is for converting the light from the second lens array 413 into one kind of polarized light, and this can improve the light use efficiency in the modulation optical system 44. It is.

  More specifically, each partial light converted into one type of polarized light by the polarization conversion element 414 is finally superimposed on the liquid crystal panel 441 of the modulation optical system 44 by the superimposing lens 415. In the rear projector 1 using the liquid crystal panel 441 of the type that modulates polarized light, only one type of polarized light can be used, so almost half of the light from the light source lamp 462 that emits other types of randomly polarized light is not used. For this reason, by using the polarization conversion element 414, all the light from the light source lamp 462 is converted into one type of polarized light, and the light use efficiency in the modulation optical system 44 is enhanced.

  The polarized light converted in the integrator illumination optical system 41 proceeds to the color separation optical system 42. The color separation optical system 42 includes two dichroic mirrors 421 and 422 and a reflection mirror 423. The dichroic mirrors 421 and 422 emit polarized light that is a plurality of partial lights emitted from the integrator illumination optical system 41. It has a function of separating light of three colors, red (R), green (G), and blue (B).

  The relay optical system 43 includes an incident side lens 431, a pair of relay lenses 433, and reflection mirrors 432 and 434. In this case, red light that is color light separated by the color separation optical system 42 is liquid crystal. It is for leading to the panel 441R.

  At this time, the dichroic mirror 421 of the color separation optical system 42 transmits the red light and the green light emitted from the integrator illumination optical system 41, and reflects the blue light. The blue light reflected by the dichroic mirror 421 is reflected by the reflection mirror 423, passes through the field lens 418, and reaches the blue liquid crystal panel 441B. The field lens 418 converts each partial light emitted from the second lens array 413 into light parallel to the central axis of the field lens 418. The field lenses 418 provided in the other liquid crystal panels 441G and 441R have the same function.

  Of the red light and green light transmitted through the dichroic mirror 421, the green light is reflected by the dichroic mirror 422, passes through the field lens 418, and reaches the liquid crystal panel 441G for green. On the other hand, the red light passes through the dichroic mirror 422, passes through the relay optical system 43, passes through the field lens 418, and reaches the liquid crystal panel 441R for red light. The reason why the relay optical system 43 is used for red light is to prevent light attenuation and the like because the optical path length of red light is longer than the optical path lengths of other color lights. In other words, the partial light incident on the incident side lens 431 is allowed to reach the field lens 418 as it is. It is also possible to use a configuration that guides blue light to the relay optical system 43.

  Next, the modulation optical system 44 modulates and combines each incident color light according to image information to form a color image. Each color light separated by the color separation optical system 42 is incident 3 Two incident-side polarizing plates 442, liquid crystal panels 441R, 441G, and 441B, which are light modulation devices disposed downstream of the respective incident-side polarizing plates 442, and emission sides disposed downstream of the respective liquid crystal panels 441R, 441G, and 441B. A polarizing plate 443 and a cross dichroic prism 444 which is a color composition device are provided.

  In this case, the liquid crystal panel 441 is of a transmission type using a polysilicon TFT as a switching element. The incident-side polarizing plate 442 transmits only polarized light in a certain direction and absorbs other light out of each color light separated by the color separation optical system 42, and is applied to a polarizing film on a substrate such as sapphire glass. Is affixed. The exit-side polarizing plate 443 is configured in substantially the same manner as the incident-side polarizing plate 442, and transmits only polarized light in a predetermined direction and absorbs other light out of the light emitted from the liquid crystal panel 441. In the liquid crystal panel 441, since the incident polarized light is twisted and emitted at a right angle, the incident-side polarizing plate 442 and the emission-side polarizing plate 443 are set so that the directions of the polarization axes thereof are orthogonal to each other.

  The cross dichroic prism 444 combines the optical images emitted from the emission-side polarizing plate 443 and modulated for each color light to form a color image. The cross dichroic prism 444 is provided with a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light in a substantially X shape along the interface of four right-angle prisms. The three color lights are combined by the multilayer film to form a color image.

  Next, the color image formed by the modulation optical system 44 is emitted by the projection optical system 45 to the reflection mirror 25 shown in FIG. The projection optical system 45 includes a projection lens unit 451 and a right-angle prism 452. The right-angle prism 452 is disposed on the light exit side of the cross dichroic prism 444 of the modulation optical system 44, and reflects the color image synthesized by the cross dichroic prism 444 by bending it toward the projection lens unit 451. The projection lens unit 451 includes a plurality of optical lenses, and emits the color image reflected by the right-angle prism 452 to the reflection mirror 25 so as to be enlarged.

  Next, the arrangement of the optical unit 40 on the exterior 10 and the cooling air flows A and B for cooling the optical unit 40 will be described. FIG. 6 is a perspective view showing a cooling air flow for cooling the optical unit. When viewed from the side, the optical unit 40 is accommodated in the lower portion of the lower exterior 13 as shown in FIG. Further, when viewed from the back side of the lower exterior 13, as shown in FIG. 6, the light source system 46 is located on the side surface 16 side having the exhaust portion 30 b, and the intake frame 50 is substantially at the center of the lower exterior 13. It is accommodated so that it may be located in. The exterior 10 accommodates the optical unit 40 in the lower exterior 13, and when the attachment / detachment cover 13a is attached, the inside other than the flow path of the cooling air flow B becomes a sealed space. In this sealed space, the cooling air flow A circulates through the optical unit 40 along the light path L and cools it.

  First, the cooling air flow A for cooling the modulation optical system 44 will be described. FIG. 7 is a cross-sectional view showing a cooling air flow for cooling the modulation optical system. The interior of the exterior 10 is partitioned from the lower exterior 13 by a boundary surface portion 15 of the upper exterior 12, and the boundary surface 15 includes a circulation inlet 15 a and a circulation outlet for circulating cooling air between the upper exterior 12 and the lower exterior 13. 15b.

  The circulation inlet 15a is provided so as to coincide with the opening of the upper part of the intake frame 50 of the optical unit 40, and the cooling air in the upper exterior 12 sequentially passes through the circulation inlet 15a and the intake frame 50. Passed through and sucked into the sirocco fan 52. The cooling air sucked into the sirocco fan 52 flows under the optical unit 40, mainly cools the modulation optical system 44, and is discharged from the optical unit 40 into the lower exterior 13. The discharged cooling air flows to the inside of the upper exterior 12 through the circulation outlet 15 b of the boundary surface portion 15. The interior of the upper exterior 12 is a wide space that is surrounded by each surface portion of the screen 20 and the upper exterior 12 and is also a light path L. Cooling air that has been warmed by cooling the optical unit 40 flows through this space, Heat is released to the outside through the surface portions 20 and the upper exterior 12. And it again circulates from the circulation inlet 15a to the lower exterior 13 side.

  In this case, it is preferable that the cooling air circulates through the upper exterior 12 without any problem. Therefore, the cooling air sucked from the circulation inlet 15a located at the substantially central portion is taken from the circulation inlet 15a to the side portion 16 so as to be taken in from the vicinity of the side portion 16 provided with the exhaust portion 30b shown in FIG. It is guided by an extending duct (not shown). The circulation inlet 15a and the sirocco fan 52 are also connected by a dedicated duct 15c (not shown). And the circulation outlet 15b is provided in the vicinity of the side part 16 on the opposite side to the side part 16 provided with the exhaust part 30b. Further, the modulation optical system 44 and the circulation outlet 15b are also connected by a duct 15d. Thereby, the cooling air flow A circulates through the inside of the upper exterior 12 to every corner.

  Such a cooling air flow A is configured to circulate through the sealed space inside the exterior 10. When the exterior 10 is first assembled in a clean room to remove the dust from the cooling air, the color of the screen 20 is subsequently obtained. It is possible to suppress the image from being affected by dust.

  Next, the cooling air flow B for cooling the light source system 46 will be described. FIG. 8 is a cross-sectional view showing a cooling air flow for cooling the light source system. As shown in FIG. 8, the sirocco fan 53 located at the lower part of the light source system 46 is connected to the light source inlet 18 provided at the attachment / detachment cover 13 a, and the exhaust duct part 54 provided at the upper part of the light source system 46 is The light source exhaust port 19 provided in the attachment / detachment cover 13a is connected. With such a configuration, the cooling air for cooling the light source system 46 is sucked into the sirocco fan 53 from the outside of the exterior 10 through the light source inlet 18 and supplied from the sirocco fan 53 to the light source device 461 of the light source system 46. . The cooling air that has cooled the light source device 461 and has exchanged heat is exhausted from the light source exhaust port 19 via the exhaust duct portion 54.

  Unlike the flow of the cooling air flow A circulating inside the exterior 10, such a cooling air flow B flows in communication with the outside via the light source intake port 18 and the light source exhaust port 19. Only the light source system 46 that generates the most heat is cooled strongly. Since the light source system 46 is less affected by dust and the like than the modulation optical system 44, the cooling effect can be given priority by introducing cooling air from the outside. Although not shown, the light source inlet 18 is provided with an air filter and takes in cooling air from which dust and the like are substantially eliminated.

  Here, also in the conventional rear projector, a sealed space having a high degree of cleanness is formed including the light path L, and cooling air is circulated in the sealed space to cool the optical unit 40 and the like. . Therefore, it is possible to avoid a situation in which the color image projected on the screen 20 is affected by dust or the like. On the other hand, it is desirable to move the rear projector to a clean room in order to maintain the cleanliness of the sealed space when performing internal inspections, parts replacement, etc. for after-sales service, etc., and perform service work at the installation site of the rear projector. So-called on-site response was considered difficult.

  The rear projector 1 of the present invention includes a dust removing unit 30 having an intake unit 30a and an exhaust unit 30b, and enables on-site correspondence. FIG. 9 is a perspective view showing a state of dust removal in the first embodiment. Hereinafter, with reference to the enlarged cross-sectional views of FIG. 9 and FIG. 2, dust removal inside the exterior 10 mainly including the upper exterior 12 that is a light path will be described. After work such as internal inspection and parts replacement, first, the intake port lid 32 of the intake unit 30a is removed. By removing the intake port lid 32, the interior of the exterior 10 is brought into communication with the exterior of the exterior 10 through the intake filter 31 of the intake portion 30a.

  Next, the exhaust port cover 36 of the exhaust part 30b is removed, and one end of the hose 61 is attached to the hose attachment part 37 of the exhaust part 30b. As a result, the interior of the exterior 10 is in communication with the interior of the hose 61 through the exhaust filter 35 of the exhaust part 30b. The other end of the hose 61 is attached to a dust collector (exhaust device) 60 that sucks dust and the like together with air. When the dust collector 60 is operated and air is started to be sucked from the hose 61, the cooling air inside the exterior 10 is exhausted to the hose 61 through the exhaust filter 35, and the inside of the exterior 10 becomes negative pressure. Therefore, air flows from the intake filter 31 into the exterior 10. As described above, since the mesh of the intake filter 31 is fine, dust and the like contained in the air introduced from the outside are removed, and the cleaned air is supplied to the inside of the exterior 10. The exhaust filter 35 is a coarser mesh than the intake filter 31, and the internal dust passes through the filter and is collected by the dust collector 60.

  Thus, a series of dust removal air flow C is formed by the suction force of the dust collector 60 to take air from the intake portion 30a into the exterior 10 and exhaust it from the exhaust portion 30b to the hose 61 together with dust and the like inside the exterior 10. Since the dust removal air flow C is formed by the external dust collector 60, it is not restricted by the size, the type of power source, the capacity, or the like as in the case of being provided inside the exterior 10. Therefore, in order to remove dust and the like from the inside of the exterior 10, it is possible to select a dust collector 60 with sufficient power, and it is possible to remove dust from the rear projector 1 by on-site correspondence.

  Hereinafter, the main effects of Embodiment 1 will be described together.

  The rear projector 1 includes the intake unit 30a and the exhaust unit 30b as the dust removing unit 30, thereby removing dust and the like from the interior of the exterior 10 at a place where the rear projector 1 is installed after an after service work. Is possible. Thereby, it is not necessary to move the rear projector 1 to a clean room or the like, and on-site correspondence is possible.

  The on-site response eliminates the labor and transportation cost of moving the rear projector 1 as in the prior art. Furthermore, dust removal of the rear projector 1 can be performed without disassembling the rear projector 1 by the intake unit 30a and the exhaust unit 30b.

  The intake portion 30a and the exhaust portion 30b are provided on the side surface portions 16 facing each other, and the dust removal air flow C flows between the side surface portions 16, so that the interior of the upper exterior 12 has almost no air retention portion. It becomes a state. Therefore, it is possible to effectively remove dust and the like inside the exterior 10 from the exhaust part 30b together with the flow of the dust removal air flow C.

The intake part 30a and the exhaust part 30b, which are the dust removal part 30, can be easily added to a rear projector that does not include the dust removal part 30 as a retrofit.
(Embodiment 2)

  Next, Embodiment 2 of the present invention will be described. The second embodiment is different from the first embodiment in the configuration of the dust removing unit. Hereinafter, differences from the first embodiment will be mainly described. FIG. 10 is a cross-sectional view showing how dust is removed in the second embodiment. As shown in FIG. 10, the dust removing unit 80 includes an exhaust unit 70 provided in the desorption cover 13 a (FIG. 6), a dust removal duct 75 that guides the cooling air flow A that has cooled the modulation optical system 44 to the exhaust unit 70, have.

  The exhaust unit 70 seals the through hole 74 provided in the attachment / detachment cover 13a, the exhaust filter 72 provided so as to close the through hole 74 on the inner side of the rear projector 1 with respect to the through hole 74, and the rear hole 74. An exhaust port lid 71 that is detachable from the outside of the projector 1, a hose attachment portion 73 that is a step protruding from the detachable cover 13 a to the outside of the rear projector 1 so as to extend the through hole 74, and an air intake portion in the first embodiment 30a (not shown).

  The dust removal duct 75 is provided in the upper part of the modulation optical system 44, and communicates with the exhaust part 70 provided in the detachable cover 13a when the detachable cover 13a is attached to the lower exterior 13. When dust removal by the dust removal unit 80 is not performed, since the exhaust port cover 71 is mounted, the cooling air flow A is not guided toward the dust removal duct 75, and from the opening / closing part 75a of the dust removal duct 75 to the circulation outlet 15b. Flowing. The opening / closing part 75a is provided so as to be openable and closable in the outer direction of the dust removal duct 75. If the dust removal duct 75 side is in a sealed state, the opening / closing part 75a opens in the outer direction of the dust removal duct 75 and allows cooling air to flow to the circulation outlet 15b.

  Then, when dust removal by the dust removal unit 80 is performed after after-service work or the like, first, the intake port cover 32 of the intake unit 30a (FIG. 2) and the exhaust port cover 71 of the exhaust unit 70 are removed and the hose of the exhaust unit 70 is attached. One end of the hose 61 is attached to the portion 73. As a result, the interior of the exterior 10 communicates with the interior of the hose 61 through the exhaust filter 72. The other end of the hose 61 is attached to a dust collector (exhaust device) 60 that sucks dust and the like together with air. When the dust collector 60 is operated and air is started to be sucked from the hose 61, the cooling air inside the exterior 10 is sucked to the hose 61 through the dust removal duct 75 and the exhaust filter 72. In this case, since the cooling air flow A is strongly sucked in the direction of the dust removal duct 75, the opening / closing part 75 a is closed, and the cooling air mainly cooling the modulation optical system 44 is guided to the dust removal duct 75.

  Thus, by adding the dust removing unit 80 connected to the dust collector 60 to the cooling device including the intake frame 50 and the sirocco fan 52 for circulating the cooling air inside the exterior 10 that is a sealed space, A series of dust removal air flow D flowing to the portion 30a, the intake frame 50, the sirocco fan 52, the dust removal duct 75, and the exhaust portion 70 is formed.

  Hereinafter, effects of the second embodiment will be described.

  The rear projector 1 includes a dust removal unit 80 having a dust removal duct 75 and an exhaust unit 70, so that dust and the like floating around the modulation optical system 44, which is the backbone of the rear projector 1, are removed intensively. Is possible.

  Further, the present invention is not limited to the above-described embodiment, and the same effects as those of the embodiment can be obtained even in the form of the following modification.

  The rear projector 1 may include both the dust removing unit 30 and the dust removing unit 80. It is possible to select and execute either the inside of the upper exterior 12 or the optical unit 40 that requires dust removal.

  The circulation outlet 15b provided in the interface 15 may have a filter. Dust and the like can be prevented from entering the upper exterior 12 from the lower exterior 13, and the light path L in the upper exterior 12 can be cleaned more efficiently.

  The configuration may be such that the intake air portion 30a and the exhaust side of the dust collector 60 are connected to circulate the dust removal air flow C or the dust removal air flow D.

  In the rear projector 1, the modulation optical system 44 uses a transmissive liquid crystal panel 441 having a light incident surface and a light exit surface different from each other. However, the reflection liquid crystal panel having the same light incident surface and the light exit surface is used. May be used. Furthermore, the present invention is not limited to using the liquid crystal panel 441, and a light modulation element other than liquid crystal such as a device using a micromirror may be used. As a result, it can be applied to various types of rear projectors, and the application range can be expanded.

The perspective view which shows the external appearance which looked at the rear projector from the front side. The perspective view which shows the external appearance and dust removal part which looked at the rear projector from the back side. Sectional drawing which shows the internal structure which looked at the rear projector from the side surface side. The perspective view which shows the external appearance of an optical unit. The schematic diagram which shows the detail inside an optical unit. The perspective view which shows the cooling air flow which cools an optical unit. Sectional drawing which shows the cooling air flow which cools a modulation optical system. Sectional drawing which shows the cooling air flow which cools a light source system. FIG. 3 is a perspective view showing how dust is removed in the first embodiment. Sectional drawing which shows the mode of dust removal in Embodiment 2. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Rear projector, 10 ... Exterior as housing, 11 ... Leg exterior, 12 ... Upper exterior, 13 ... Lower exterior, 14 ... Front exterior, 15 ... Boundary surface part, 15a ... Circulation inlet, 15b ... Circulation outlet , 18 ... Light source inlet, 19 ... Light source outlet, 20 ... Screen, 25 ... Reflection mirror, 30 ... Dust removal part, 30a ... Intake part, 30b ... Exhaust part, 31 ... Intake filter, 32 ... Inlet cover, 35 DESCRIPTION OF SYMBOLS ... Exhaust filter, 36 ... Exhaust port cover, 37 ... Hose attachment part, 40 ... Optical unit, 50 ... Intake frame, 52, 53 ... Sirocco fan, 52a ... Fan inlet, 54 ... Exhaust duct part, 60 ... Exhaust device As a dust collector, 61 ... hose, 70 ... exhaust part, 71 ... exhaust port lid, 72 ... exhaust filter, 75 ... dust removal duct, 75a ... opening / closing part, A ... cooling air flow, B ... cooling air flow, C, D ... dust removal Air flow

Claims (5)

An optical unit that modulates a light beam emitted from a light source according to image information and performs an enlarged projection, a housing that houses the optical unit, a light beam that is provided on a side surface of the housing and is projected from the optical unit. A rear projector having a screen for projection,
An intake section having an intake filter and an intake port lid;
An exhaust part having an exhaust filter and an exhaust port lid is provided in the housing;
The rear projector is characterized in that the dust inside the casing is removed by removing the air inlet lid and the exhaust outlet lid and forcibly exhausting the air inside the casing by an exhaust device connected to the exhaust section. The rear projector according to claim 1,
The rear projector has a finer mesh than the exhaust filter, and excludes dust that is projected to the screen so as to be visible. The rear projector according to claim 1 or 2,
The rear projector characterized in that the intake section and the exhaust section are respectively provided on opposing surfaces of the casing. An optical unit that modulates a light beam emitted from a light source according to image information and performs an enlarged projection, a housing that houses the optical unit, a light beam that is provided on a side surface of the housing and is projected from the optical unit. A rear projector having a screen for projection,
A cooling device for circulating cooling air in a sealed space inside the housing;
An exhaust part provided in the housing and having an exhaust filter and an exhaust port lid;
A duct for communicating the sealed space and the exhaust part,
The rear projector is characterized in that dust removal in the sealed space is performed by removing the exhaust port lid and forcibly exhausting the air in the sealed space by an exhaust device connected to the exhaust unit. The rear projector according to claim 4,
The rear projector, wherein the sealed space includes a path of the light beam.

Images