JP2015158643A - image projection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image projection device that can inject an air for cleaning toward optical components to enable efficient cleaning of the optical components according to the positions and shapes of the optical components.SOLUTION: An image projection device includes an air guide path (air guide duct 61) that guides an air for cleaning to optical components to be cleaned (for example, color wheel 23 and light tunnel 25), and a movable nozzle 65 that is arranged at one end of the air guide path and has an injection port to inject the air toward the optical components, where the movable nozzle can advance and retreat between a cleaning position to inject the air from the injection port to clean the optical components and a retreat position not to inject the air from the injection port.

Description

  The present invention relates to an image projection apparatus, and more particularly, to an image projection apparatus in which, when dust adheres to an optical component constituting the image projection apparatus, the attached dust can be easily removed by blowing it off with a gas.

In order not to deteriorate the quality of the image projected by the image projection apparatus, it is necessary to prevent the dust from adhering to the optical components constituting the image projection apparatus. For this reason, many of the optical components constituting the image projection apparatus are accommodated in a sealed space where dust does not enter.
On the other hand, there are optical components that cannot be placed in a sealed space in the housing. For example, a color wheel or a light tunnel. The color wheel is a component that converts white light from the light source unit into light that repeats each color of RGB every unit time while rotating at high speed. The light tunnel is a component that uniformizes the illuminance distribution of the light emitted from the color wheel and leads it to the relay lens at the next stage. In both the color wheel and the light tunnel, the adhesion of dust affects the brightness of the projected image, so it is necessary to prevent the dust from adhering to these optical components. However, the color wheel and the light tunnel are components in which heat generated by light continuously irradiated from the light source unit accumulates and needs to be cooled. For this reason, these optical components are accommodated in a non-sealed state in the housing in order to enable cooling by air.
In order to prevent dust from adhering to the color wheel and the light tunnel, it is also effective to provide a filter that traps dust at the outside air intake port located at the appropriate position of the housing. It is difficult to prevent completely.
Therefore, Patent Document 1 describes an image projection apparatus provided with an air blowing device that removes dust adhering to an optical component. This air blowing device maintains the quality of a projected image by blowing air on the surface of a projection lens as an optical component to forcibly blow off dust.

Here, in the image projection apparatus described in Patent Document 1, in order to inject air along the surface of the projection lens, a nozzle for injecting air is arranged on the side of the projection lens. For this reason, the projection lens can be efficiently cleaned while the nozzle is in a position that does not affect the projected image. However, depending on the position and shape of the optical component to be cleaned, it may be difficult to efficiently clean the optical component without affecting the projected image even if the arrangement of the nozzles is devised.
The present invention has been made in view of the above-described circumstances, and a cleaning gas is jetted toward an optical component so that the optical component can be efficiently cleaned according to the position and shape of the optical component. An object is to provide a possible image projection apparatus.

  In order to solve the above-described problems, the invention described in claim 1 includes a light source unit having a light source, an image forming unit that forms an image using light emitted from the light source, and the image forming unit. A projection unit for projecting a formed image toward a projection surface, and the optical source as a cleaning target constituting the light source unit, the image forming unit, or the projection unit for cleaning. An air guide path for introducing gas; and a movable nozzle that is disposed at one end of the air guide path and has an injection port for injecting gas toward the optical component, the movable nozzle from the injection port It is configured to be able to advance and retreat between a cleaning position for injecting gas to clean the optical component and a retracted position for injecting no gas from the injection port.

  In the present invention, the movable nozzle is retracted to the retracted position when not being cleaned and moved to a cleaning position suitable for cleaning the optical component during cleaning, so that the optical component can be efficiently cleaned according to the position and shape of the optical component.

It is a perspective view which shows the positional relationship of the projector and projection surface which concern on one Embodiment of this invention. It is the figure which showed typically the horizontal cross section (YZ cross section) of a projector. It is an enlarged view around the movable nozzle of the cleaning unit, (a) shows the case where the movable nozzle is in the retracted position, (b) shows the case where the movable nozzle is in the cleaning position.

  Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the components, types, combinations, shapes, relative arrangements, and the like described in this embodiment are merely illustrative examples and not intended to limit the scope of the present invention only unless otherwise specified. . In the present invention, air or high-pressure gas is sent toward an optical component, and dust attached to the optical component is blown off by wind pressure to be removed.

[Basic projector configuration-external]
First, an embodiment of a projector as an image projection apparatus to which an embodiment of the present invention is applied will be described. FIG. 1 is a perspective view showing a positional relationship between a projector and a projection surface according to an embodiment of the present invention. In the following description, the normal direction of the projection surface S is the X direction, the short axis direction (vertical direction) of the projection surface is the Y direction, and the long axis direction (horizontal direction) of the projection surface S is the Z direction.
As shown in FIG. 1, a transmissive glass 101 that emits a projection image P is provided on the upper surface of the projector 1, and the projection image P emitted from the transmissive glass 101 is projected onto a projection surface S such as a screen. The
An operation unit 102 for the user to operate the projector 1 is provided on the upper surface of the projector 1. A focus lever 103 for adjusting the focus is provided on the side surface of the projector 1. By operating the operation unit 102 including a well-known input mechanism such as a button, it is possible to perform network settings such as color tone and contrast adjustment of the projected image P, or IP address setting.

[Internal configuration of projector-Internal]
FIG. 2 is a diagram schematically showing a horizontal section (YZ section) of the projector. The projector 1 includes a light source unit 10 including an arc tube 11 as a light source, an image forming unit 20 that forms an image using illumination light emitted from the arc tube 11, and an image formed by the image forming unit 20. Is projected toward the projection surface. The image forming unit 20 includes an image display element mechanism 33 as an image generation element that modulates light based on image data, and an illumination unit 21 that irradiates the image display element mechanism 33 with light from a light source. The projector 1 also includes a control unit 50 that controls the operation of each unit of the projector 1.
The light source unit 10 is a device that emits white light toward the illumination unit 21, and includes an arc tube 11 and a reflector 13. As the arc tube 11, for example, a halogen lamp, a xenon lamp, a metal halide lamp, an ultrahigh pressure mercury lamp, or the like can be used. The reflector 13 reflects and collects light from the arc tube 11 in order to efficiently obtain light with high illuminance.

The illumination unit 21 includes a color wheel 23, a light tunnel 25, relay lenses 27 (27a, 27b), a plane mirror 29, and a concave mirror 31.
The color wheel 23 has a disk shape, converts white light from the light source unit 10 into light in which each color of RGB repeats every unit time, and emits the light toward the light tunnel 25. The light tunnel 25 is disposed downstream of the color wheel 23 in the light emission direction, and is configured in a cylindrical shape by laminating plate glasses. The light tunnel 25 propagates the light emitted from the color wheel 23 while reflecting the light from the inner surface of the hollow portion, thereby converting the light into a uniform light illuminance distribution (intensity distribution) and directing the light toward the relay lens 27. And inject. The illustrated relay lens 27 is configured by combining two lenses 27a and 27b, and condenses light while correcting axial chromatic aberration of light emitted from the light tunnel 25. The plane mirror 29 and the concave mirror 31 reflect the light emitted from the relay lens 27 and guide it to the image display element mechanism 33 to collect it.

The image display element mechanism 33 has a rectangular mirror surface composed of a plurality of micromirrors, and each micromirror is driven in a time-sharing manner based on video data, so that projection light is generated so as to form a predetermined video. A DMD (Digital Micro-mirror Device) element that is processed and reflected is provided.
The projection unit 40 includes a plurality of projection lenses 41 that project the image formed by the image display element mechanism 33 toward the external projection surface S as projection light L.

In the illumination unit 21, the white light emitted from the light source unit 10 is separated into RGB by the color wheel 23 and guided to the image display element mechanism 33. The image display element mechanism 33 forms an image according to the modulation signal based on the video data, and reflects the light used for the projection image to the projection unit 40 by each micromirror. The light reflected to the projection unit 40 is enlarged in the process of passing through the plurality of projection lenses 41, and enlarged and projected onto the projection surface S as the projection light L. In the image display element mechanism 33, unnecessary light that is not used in the projection image is reflected by each micromirror to an OFF light plate (not shown).
The controller 50 controls the voltage applied to the arc tube 11 so that the arc tube 11 emits light with a predetermined light amount or stops light emission. The control unit 50 controls the color wheel 23 so that the color wheel 23 rotates at a predetermined speed or stops rotating.

[Cleaning unit]
A projector according to an embodiment of the present invention will be described with reference to FIGS. The projector 1 according to the present embodiment includes a cleaning unit 60 that removes dust adhering to optical components constituting the projector 1 by air blowing. 3A and 3B are enlarged views of the vicinity of the movable nozzle of the cleaning unit. FIG. 3A shows the case where the movable nozzle is at the retracted position, and FIG. 3B shows the case where the movable nozzle is at the cleaning position.
The cleaning unit 60 is arranged at an appropriate position of the air guide pipe 61 (air guide path) for guiding the cleaning air (cleaning gas) to the optical part to be cleaned, and gas toward the optical part. And a movable nozzle 65 having an injection port 67 for injecting. The movable nozzle 65 has a cleaning position (position shown in FIG. 3B) for cleaning the optical component by the cleaning air ejected from the ejection port 67, and a retracted position (FIG. 3 (a) where gas is not ejected from the ejection port 67. It is configured to be able to move forward and backward.
Here, the optical component as a cleaning target is a component constituting the light source unit 10, the image forming unit 20, or the projection unit 40. In particular, in the present embodiment, the light tunnel 25 and the color wheel 23 constituting the illumination unit 21 of the image forming unit 20 are to be cleaned.

The air guide tube 61 is in the form of a hollow pipe, and is arranged avoiding the optical path. A movable nozzle 65 is disposed at one end portion 61a of the air guide tube 61, and a connection port 63 to which a generation source of cleaning air is connected is provided at the other end portion 61b. The connection port 63 is an opening provided at an end portion of the air guide tube 61 and is disposed at an appropriate position on the housing side surface 1 a of the projector 1.
In addition, you may provide the cover member which closes the connection port 63. FIG. When the light tunnel 25 and the color wheel 23 are not cleaned, the connection port 63 can be closed with a lid member to prevent dust from entering the air guide tube 61.
The generation source of the cleaning air is, for example, an aerosol spray such as an air duster, or a compressor (not shown) that compresses and injects air. In the illustrated example, the nozzle 111 of the air duster 110 is inserted into the air guide tube 61. Compressed air is fed into the air guide pipe 61 as cleaning air. A gas other than air may be used for cleaning the optical component.

As shown in FIG. 3, the movable nozzle 65 has a substantially hollow cylindrical shape with one axial end (lower in the figure) opened and the other axial end (upper in the figure) closed. One end portion 61 a of the air guide tube 61 is inserted into the hollow portion of the movable nozzle 65 from one end opening thereof.
An injection port 67 is formed at a suitable position on the outer peripheral surface of the movable nozzle 65. The injection port 67 is a communication hole that communicates the inside and outside of the movable nozzle 65.
The air pressure in the air guide pipe 61 rises when cleaning air is sent from the air duster 110. The movable nozzle 65 is pushed up as the atmospheric pressure in the air guide tube 61 increases, and moves to the cleaning position while sliding with respect to the air guide tube 61. The air pressure in the air guide pipe 61 is lowered when the cleaning air from the air duster 110 is not sent. The movable nozzle 65 descends as the atmospheric pressure in the air guide tube 61 decreases, and moves to the retracted position while sliding with respect to the air guide tube 61. Since the movable nozzle 65 mechanically operates according to the rise and fall of the atmospheric pressure, no special control means or the like is required, and the configuration of the cleaning unit 60 can be simplified.

The cleaning unit 60 includes a coil spring 71 (elastic urging member) that constantly urges the movable nozzle 65 to the retracted position. The coil spring 71 is disposed across the movable nozzle 65 and the air guide tube 61.
That is, a flange portion 69 protruding in the outer diameter direction is formed at one axial end portion of the movable nozzle 65. One end of the coil spring 71 is locked to the flange portion 69. Further, the outer diameter of the one end portion 61a of the air guide tube 61 is larger than that of the intermediate portion, and a stepped portion 64 is formed on the outer peripheral portion. The other end of the coil spring 71 is locked to the stepped portion 64.
As described above, the coil spring 71 always elastically biases the movable nozzle 65 to the retracted position. Therefore, when the cleaning air is not sent into the air guide tube 61, the movable nozzle 65 smoothly moves from the cleaning position to the retracted position. Can be moved to. In particular, the movable nozzle 65 protrudes on the optical path at the cleaning position and retracts from the optical path at the retracted position. By providing the coil spring 71, it is possible to prevent the movable nozzle 65 from protruding onto the optical path when the optical component is not cleaned.
Note that when the cleaning air is no longer sent into the air guide pipe 61, the movable nozzle 65 may be lowered by its own weight and moved to the retracted position.

The movable nozzle 65 is disposed immediately downstream of the light tunnel 25 in the light emission direction. When the movable nozzle 65 is at the cleaning position, the ejection port 67 ejects cleaning air into the light tunnel 25 from the downstream side in the light emission direction toward the upstream side. The inside of the light tunnel 25 can be cleaned by the cleaning air. Further, since the cleaning air that has passed through the light tunnel 25 is blown to the color wheel 23, the color wheel 23 can be cleaned simultaneously with the light tunnel 25.
The movable nozzle 65 is not allowed to be on the optical path at least when the projection image P is projected. Therefore, it is also possible to arrange the nozzle portion in which the injection port 67 is formed at a position that always avoids the optical path, and to jet the gas from the position to clean the optical component. However, from the position where the optical path is avoided, there are cases where the optical component cannot be sufficiently cleaned due to the relationship between the jetting direction and jetting strength of the cleaning air. For example, in order to clean the inside of a cylindrical optical component such as the light tunnel 25 having the hollow portion as the optical path, at least a part of the cleaning unit 60 (here, the movable nozzle 65) needs to protrude on the optical path. is there.
According to this embodiment, when the optical component is not cleaned, the movable nozzle 65 is retracted from the optical path, and when the optical component is cleaned, the movable nozzle 65 protrudes on the optical path, thereby affecting the projected image. Without giving, the optical component can be efficiently cleaned from the position and direction suitable for cleaning the optical component.

A side surface 62 of the wind guide tube 61 located at one end 61a of the wind guide tube 61 closes the injection port 67 when the movable nozzle 65 is in the retracted position. That is, the side surface 62 functions as a closing unit that closes the flow path of the cleaning air from the air guide pipe 61 to the injection port 67 when the movable nozzle 65 is in the retracted position. When the optical component is not cleaned, the injection port 67 is closed, and the flow of gas from the air guide tube 61 to the periphery of the optical component to be cleaned is prevented, thereby preventing unnecessary dust from adhering to the optical component. To do.
When the movable nozzle 65 protrudes to the cleaning position, the injection port 67 is positioned beyond the other end of the air guide tube 61 and does not face the side surface 62. Therefore, when the movable nozzle 65 protrudes to the cleaning position, the inside of the hollow portion of the air guide tube 61 communicates with the space outside the movable nozzle 65 through the one end opening of the air guide tube 61 and the injection port 67, and the injection port 67. Cleaning air is injected from On the other hand, when the movable nozzle 65 is retracted to the retracted position, the inside of the hollow portion of the air guide tube 61 and the space outside the movable nozzle 65 are not in communication with each other, and cleaning air is not ejected from the ejection port 67.

<Connection detection sensor>
A connection detection sensor 91 (connection detection means) for detecting that the air duster 110 is connected to the wind guide pipe 61 is disposed at an appropriate position (near the connection port 63) of the other end portion 61b of the wind guide pipe 61. . As the connection detection sensor 91, for example, it protrudes into the air guide tube 61 at all times, and is pushed by the nozzle 111 and retracts from the air guide tube 61 when the nozzle 111 of the air duster 110 is inserted into the air guide tube 61. The detection piece 93 and a transmission type photosensor that detects the position (or posture) of the detection piece 93 can be used.

The control unit 50 controls the light source unit 10 based on the detection signal (detection result) from the connection detection sensor 91 when the connection detection sensor 91 detects the connection of the air duster 110 to the air duct 61. Functions as a means. Specifically, when the connection detection sensor 91 detects that the air duster 110 is connected to the air guide tube 61, the control unit 50 causes the light emitting tube 11 to reduce the amount of emitted light or stop light emission. The voltage applied to the arc tube 11 is controlled. Thus, when performing dust removal by air blow, it is possible to prevent unnecessary images from being projected onto the projection surface S by reducing the amount of emitted light or stopping light emission.
Further, the control unit 50 serves as drive control means for driving and controlling the color wheel 23 based on a detection signal from the connection detection sensor 91 when the connection detection sensor 91 detects the connection of the air duster 110 to the wind guide pipe 61. Function. Specifically, when the connection detection sensor 91 detects that the air duster 110 is connected to the air guide pipe 61, the control unit 50 causes the color wheel 23 to rotate at a predetermined rotational speed. 23 is rotated. By rotating the color wheel 23 in this way, the dust D ejected from the light tunnel 25 can be prevented from adhering to the color wheel 23. Further, the surface of the color wheel 23 can be uniformly cleaned by the cleaning air blown to the color wheel 23 through the light tunnel 25.

<Position detection sensor>
In the vicinity of the movable nozzle 65, a position detection sensor 95 (position detection means) for detecting the position of the movable nozzle 65 is disposed. As the position detection sensor 95, a transmissive photosensor that detects protrusions or the like provided on the movable nozzle 65 can be used.

The control unit 50 is a light source control unit that controls the light source unit 10 based on a detection signal (detection result) from the position detection sensor 95 when the position detection sensor 95 detects that the movable nozzle 65 is at the cleaning position. Function. Specifically, when the position detection sensor 95 detects that the movable nozzle 65 is at the cleaning position, the control unit 50 moves the light emitting tube 11 to the light emitting tube 11 so that the light emitting tube 11 reduces the light emission amount or stops light emission. Control the voltage to be applied. Thus, when performing dust removal by air blow, it is possible to prevent unnecessary images from being projected onto the projection surface S by reducing the amount of emitted light or stopping light emission.
Furthermore, the control unit 50 functions as a drive control unit that drives and controls the color wheel 23 based on a detection signal from the position detection sensor 95 when the position detection sensor 95 detects that the movable nozzle 65 is in the cleaning position. . Specifically, when the position detection sensor 95 detects that the movable nozzle 65 is at the cleaning position, the control unit 50 drives the color wheel 23 so that the color wheel 23 rotates at a predetermined rotation speed. Let By rotating the color wheel 23 in this way, the dust D ejected from the light tunnel 25 can be prevented from adhering to the color wheel 23. Further, the surface of the color wheel 23 can be uniformly cleaned by the cleaning air blown to the color wheel 23 through the light tunnel 25.
When the connection detection sensor 91 or the position detection sensor 95 detects that the air duster 110 is connected or the movable nozzle 65 is in the cleaning position, the control unit 50 controls the color of the light source unit 10 and the color. At least one of the control of the wheel 23 may be performed.

[Example Embodiments and Effects]
The present invention can be implemented in the following modes.
<First embodiment>
A light source unit 10 having a light source (light emitting tube 11), an image forming unit that forms an image using light emitted from the light source, and a projection that projects an image formed by the image forming unit toward the projection surface S In an image projection apparatus (projector 1) provided with a unit 40, a gas for cleaning to a light source unit, an image forming unit, or an optical component (for example, a color wheel 23, a light tunnel 25) as a cleaning target constituting the projection unit. An air guide path (air guide pipe 61) for guiding (cleaning air), and a movable nozzle 65 disposed at one end of the air guide path and having an injection port 67 for injecting gas toward the optical component. The movable nozzle has a cleaning position (see FIG. 3B) for cleaning the optical component by injecting gas from the injection port, and a retreat position (see FIG. 3A) for not injecting gas from the injection port. Characterized in that it is configured to advance and retreat between.
The movable nozzle is retracted to the retracted position when not cleaned, and moved to a cleaning position suitable for cleaning the optical component during cleaning, so that the optical component can be efficiently cleaned according to the position and shape of the optical component.

<Second embodiment>
The movable nozzle 65 is configured to move to a cleaning position or a retracted position as the atmospheric pressure in the air guide path (air guide pipe 61) increases or decreases.
Since the movable nozzle 65 mechanically operates according to the rise and fall of the atmospheric pressure, no special control means or the like is required, and the configuration of the cleaning unit 60 can be simplified.

<Third embodiment>
An elastic urging member (coil spring 71) that constantly urges the movable nozzle 65 to the retracted position is provided.
When the optical component is not cleaned, the movable nozzle 65 can be prevented from remaining protruding to the cleaning position.

<Fourth embodiment>
When the movable nozzle 65 is in the retracted position, a closing means (side surface 62) for closing a gas flow path from the air guide path (air guide pipe 61) to the injection port 67 is provided.
When the optical component is not cleaned, the injection port 67 is closed, and the flow of gas from the air duct 61 to the periphery of the optical component to be cleaned is prevented, thereby preventing unnecessary dust from adhering to the optical component.

<Fifth embodiment>
The movable nozzle 65 protrudes on the optical path at the cleaning position and retracts from the optical path at the retracted position.
The movable nozzle 65 is not allowed to be on the optical path at least when the projection image P is projected. Therefore, it is also possible to arrange the nozzle portion in which the injection port 67 is formed at a position that always avoids the optical path, and to jet the gas from the position to clean the optical component. However, from the position where the optical path is avoided, there are cases where the optical component cannot be sufficiently cleaned due to the relationship between the jetting direction and jetting strength of the cleaning air.
According to this embodiment, when the optical component is not cleaned, the movable nozzle 65 is retracted from the optical path, and when the optical component is cleaned, the movable nozzle 65 protrudes on the optical path without affecting the projected image. The optical component can be efficiently cleaned from a position and a direction suitable for cleaning the optical component.

<Sixth embodiment>
A connection detection means (connection detection sensor) that is disposed at an appropriate position on the other end portion 61b of the air guide path (air guide pipe 61) and detects that the cleaning gas generation source (air duster 110) is connected to the air guide path. 91) and light source control means (control unit 50) for controlling the operation of the light source (luminous tube 11) based on the detection result (detection signal) of the connection detection means, and the generation source of the cleaning gas is a wind guide When the connection detection unit detects that the light source is connected to the road, the light source control unit controls the light source to reduce the light emission amount or stop the light emission.
When performing dust removal by air blow, it is possible to prevent unnecessary images from being projected onto the projection surface S by reducing the amount of emitted light or stopping light emission.

<Seventh embodiment>
The optical component to be cleaned is a color wheel 23 that constitutes the image forming unit 20 and converts light from the light source (the arc tube 11) into light in which a plurality of colors repeat every unit time. A connection detection means (connection detection sensor 91) which is disposed at an appropriate position on the other end portion 61b of the (wind guide pipe 61) and detects that the cleaning gas generation source (air duster 110) is connected to the wind guide path; Drive control means (control unit 50) for controlling the operation of the color wheel based on the detection result (detection signal) of the connection detection means, and that the generation source of the cleaning gas is connected to the air guide path When the connection detection means detects, the drive control means rotates the color wheel.
The surface of the color wheel 23 can be cleaned by blowing cleaning air onto the color wheel 23. Moreover, the surface of the color wheel 23 can be uniformly cleaned by rotating the color wheel 23 at the time of cleaning.

<Eighth embodiment>
Position detection means (position detection sensor 95) for detecting the position of the movable nozzle 65, and light source control means (control section 50) for controlling the operation of the light source (light emitting tube 11) based on the detection result (detection signal) of the position detection means. ), And when the position detection means detects that the movable nozzle is at the cleaning position, the light source control means controls the light source to reduce the amount of emitted light or stop emitting light. .
When performing dust removal by air blow, it is possible to prevent unnecessary images from being projected onto the projection surface S by reducing the amount of emitted light or stopping light emission.

<Ninth Embodiment>
The optical component to be cleaned is the color wheel 23 that constitutes the image forming unit 20 and converts light from the light source (the arc tube 11) into light in which a plurality of colors repeat every unit time. A position detection means (position detection sensor 95) for detecting the position of the color wheel, and a drive control means (control unit 50) for controlling the operation of the color wheel based on the detection result (detection signal) of the position detection means. When the position detecting means detects that the nozzle is at the cleaning position, the drive control means rotates the color wheel.
The surface of the color wheel 23 can be cleaned by blowing cleaning air onto the color wheel 23. Moreover, the surface of the color wheel 23 can be uniformly cleaned by rotating the color wheel 23 at the time of cleaning.

<Tenth embodiment>
The image forming unit 20 includes a cylindrical light tunnel 25 that makes the illuminance distribution of light emitted from the color wheel uniform on the downstream side of the color wheel 23 in the light emission direction, and the movable nozzle 65 emits light from the light tunnel. When the movable nozzle is at the cleaning position, the injection port 67 injects a cleaning gas (cleaning air) into the light tunnel from the downstream side in the light emission direction toward the upstream side. It is characterized by that.
The inside of the light tunnel 25 can be cleaned by the cleaning air ejected from the ejection port 67. Further, since the cleaning air that has passed through the light tunnel 25 is blown to the color wheel 23, the color wheel 23 can be cleaned simultaneously with the light tunnel 25.

  DESCRIPTION OF SYMBOLS 1 ... Projector (image projection apparatus), 1a ... Housing side surface, 10 ... Light source unit, 11 ... Light emission tube (light source), 13 ... Reflector, 20 ... Image forming unit, 21 ... Illumination unit, 23 ... Color wheel, 25 ... Light tunnel, 27 ... Relay lens, 27a ... Lens, 29 ... Flat mirror, 31 ... Concave mirror, 33 ... Image display element mechanism, 40 ... Projection unit, 41 ... Projection lens, 50 ... Control unit (light source control means, drive control) Means), 60 ... Cleaning unit, 61 ... Air guide pipe (air guide path), 61a ... One end part, 61b ... Other end part, 62 ... Side face, 63 ... Connection port, 64 ... Step part, 65 ... Movable nozzle, 67 DESCRIPTION OF SYMBOLS ... Injection port, 69 ... Flange part, 71 ... Coil spring, 91 ... Connection detection sensor (connection detection means), 93 ... Detection piece, 95 ... Position detection sensor (position detection means), 101 ... Transmission glass , 102 ... operation unit, 103 ... focus lever, 110 ... (a source of cleaning gas) air duster, 111 ... nozzle, S ... projection surface, P ... projected image

JP 2006-220835 A

Claims (10)

A light source unit having a light source, an image forming unit that forms an image using light emitted from the light source, and a projection unit that projects an image formed by the image forming unit toward a projection surface. In the image projection device
An air guide path that guides a cleaning gas to an optical component as a cleaning target that constitutes the light source unit, the image forming unit, or the projection unit, and is disposed at one end of the air guide path. A movable nozzle having an injection port for injecting gas toward the
The movable nozzle is configured to be movable back and forth between a cleaning position for cleaning the optical component by injecting gas from the injection port and a retreat position for not discharging gas from the injection port. Image projection device.   The image projecting apparatus according to claim 1, wherein the movable nozzle is configured to move to the cleaning position or the retracted position as the atmospheric pressure in the air guide path increases or decreases.   The image projection apparatus according to claim 1, further comprising an elastic biasing member that constantly elastically biases the movable nozzle to the retracted position.   4. The apparatus according to claim 1, further comprising a closing unit that closes a gas flow path from the air guide path to the injection port when the movable nozzle is in the retracted position. 5. The image projection apparatus described in 1.   5. The image projection apparatus according to claim 1, wherein the movable nozzle protrudes on the optical path at the cleaning position and retracts from the optical path at the retreat position. 6. Based on the detection result of the connection detection means, the connection detection means that is disposed at a suitable position on the other end side of the air guide path and detects that the generation source of the cleaning gas is connected to the air guide path. A light source control means for controlling the operation of the light source,
When the connection detection unit detects that the generation source of the cleaning gas is connected to the air guide path, the light source control unit controls the light source to reduce the amount of emitted light or stop light emission. The image projection apparatus according to claim 1, wherein the image projection apparatus is an image projection apparatus. The optical component as the object to be cleaned is a color wheel that constitutes the image forming unit and converts light from the light source into light that repeats a plurality of colors every unit time.
Based on the detection result of the connection detection means, the connection detection means that is disposed at a suitable position on the other end side of the air guide path and detects that the generation source of the cleaning gas is connected to the air guide path. Drive control means for controlling the operation of the color wheel,
The drive control means rotates the color wheel when the connection detection means detects that the cleaning gas generation source is connected to the air guide path. The image projection device according to any one of the above. A position detection means for detecting the position of the movable nozzle; and a light source control means for controlling the operation of the light source based on a detection result of the position detection means,
The light source control means controls the light source to reduce the light emission amount or stop the light emission when the position detection means detects that the movable nozzle is at the cleaning position. Item 6. The image projection device according to any one of Items 1 to 5. The optical component as the object to be cleaned is a color wheel that constitutes the image forming unit and converts light from the light source into light that repeats a plurality of colors every unit time.
A position detection means for detecting the position of the movable nozzle; and a drive control means for controlling the operation of the color wheel based on the detection result of the position detection means,
The drive control means rotates the color wheel when the position detection means detects that the movable nozzle is at the cleaning position, or any one of claims 1 to 5, The image projection apparatus according to claim 8. The image forming unit includes a cylindrical light tunnel that makes the illuminance distribution of the light emitted from the color wheel uniform on the downstream side in the light emission direction from the color wheel,
The movable nozzle is disposed immediately downstream of the light tunnel in the light emission direction, and when the movable nozzle is at the cleaning position, the injection port is located in the light tunnel from the light emission direction downstream side to the upstream side. The image projection apparatus according to claim 7, wherein a cleaning gas is jetted.

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