JP2017049338A - Light tunnel holding structure, illumination unit, optical engine and image projection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light tunnel holding structure that can efficiently conduct adjustment works of a holding position of a light tunnel.SOLUTION: A holding structure of a light tunnel 22 comprises: a first clamp unit 221 that is fixed to an illumination bracket 26, clamping left/right lateral faces 22a and 22b of a quadrangular cylinder shape light tunnel 22, and allows clamping forces Fa and Fb of the left/right lateral faces 22a and 22b to be adjusted; and a second clamp unit 222 that is fixe to the illumination bracket 26, clamping upper/lower faces 22c and 22d of the light tunnel 22, and allows clamping forces Fc and Fd of the upper/lower faces 22c and 22d to be adjusted. Pressure force Fc depressing the upper face 22c of the light tunnel 22 of the second clamp unit 222 is greater than friction force between the first clamp unit 221 and the left/right lateral faces 22a and 22b of the light tunnel 22.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a light tunnel holding structure, an illumination unit, an optical engine, and an image projection apparatus.

  2. Description of the Related Art Conventionally, there has been used an image projection apparatus that generates video light based on image data from a personal computer or a video camera using light from a light source and projects the generated video light on a projection surface such as a screen.

  As this image projection apparatus, for example, an image projection apparatus disclosed in Patent Document 1 is known. The image projection apparatus disclosed in Patent Document 1 generates image light by irradiating an image generation element with light from a light source by an illumination unit, and projects the image light onto a projection surface.

  The lighting unit includes a square tubular light tunnel. This light tunnel is held by a lighting bracket. The holding structure of the light tunnel includes a first holding portion that is fixed to the lighting bracket by holding one facing surface of the light tunnel, and a second holding portion that is fixed to the lighting bracket by holding the other facing surface of the light tunnel. A part.

  The first clamping unit can adjust the clamping force of one opposing surface of the light tunnel, and the second clamping unit can adjust the clamping force of the other opposing surface of the light tunnel. The holding position of the light tunnel is adjusted by adjusting the clamping force of both clamping parts.

  However, in the light tunnel holding structure of Patent Document 1, the maximum clamping force of both clamping parts is set to the same clamping force. For this reason, even if the operator holds the light tunnel with both holding parts with the maximum holding force and then weakens the holding force of one holding part to adjust the holding position, the light tunnel is fixed by the other holding part. Does not move to

  Therefore, the operator must adjust the holding position by picking the light tunnel, or once remove the light tunnel from the lighting bracket and reassemble it to the lighting bracket to adjust the holding position from the beginning. Therefore, the holding structure of the light tunnel disclosed in Patent Document 1 cannot perform the holding position adjustment operation efficiently.

  The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide a light tunnel holding structure capable of efficiently adjusting the holding position of the light tunnel.

  The light tunnel holding structure of the present invention includes a first sandwiching portion that is fixed to an illumination bracket by sandwiching one opposing surface of a square tube-shaped light tunnel, and the clamping force of the one opposing surface is adjustable, and the light A second sandwiching portion that is fixed to the lighting bracket by sandwiching the other facing surface of the tunnel and capable of adjusting the sandwiching force of the other facing surface, and one of the first sandwiching portion and the second sandwiching portion. A pressing force for pressing one side of the facing surface is larger than a frictional force between the other of the first sandwiching portion or the second sandwiching portion and the facing surface.

  According to the light tunnel holding structure of the present invention, the light tunnel holding position can be adjusted efficiently.

It is a perspective view at the time of use of the image projector which concerns on one embodiment of this invention. FIG. 2 is a perspective view of an image projection apparatus main body with an exterior cover removed from the image projection apparatus of FIG. 1 and a power supply board unit removed. It is a perspective view of an optical element group and an image generation unit of the illumination unit according to the embodiment. It is the schematic side view which looked at the optical engine which concerns on the embodiment from the light source side. It is the schematic perspective view which looked at the illumination unit in FIG. 2 from the back side. It is sectional drawing of the A section of FIG. It is sectional drawing which looked at the holding structure of the light tunnel which concerns on the embodiment from the incident side. It is a front view of the projection lens unit which concerns on the same embodiment. It is a longitudinal cross-sectional view of FIG. It is an enlarged view of the attachment part of the projection lens unit which concerns on the same embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view when an image projection apparatus 1 according to an embodiment of the present invention is used. The image projection apparatus 1 generates image light Lc based on image data from a personal computer, a video camera, or the like, using light from a light source, and a projection surface such as a screen arranged in front of the generated image light Lc. 101 is projected.

  First, the basic configuration of the image projector 1 will be described. The image projection apparatus 1 includes an exterior cover 3, an image projection apparatus body 2 provided inside the exterior cover 3, and a power supply board unit attached to the image projection apparatus body 2.

  FIG. 2 is a perspective view of the image projection apparatus main body 2 with the exterior cover 3 removed from the image projection apparatus 1 of FIG. 1 and the power supply board unit removed. As shown in FIG. 2, the image projection apparatus main body 2 generates a video light Lc based on image data using the light source unit 10 and light from the light source unit 10, and projects the generated video light Lc onto the projection plane 101. And an optical engine 100.

  The optical engine 100 includes an illumination unit 20 that receives light from the light source unit 10 and an image generation unit 30 that receives the light from the illumination unit 20 and generates video light. Furthermore, the optical engine 100 includes a projection optical system unit 40 that projects the video light generated by the image generation unit 30 onto a projection surface.

  Next, the configuration of each unit will be described.

<Light source unit 10>
The light source unit 10 includes a light source 11, a holder 12 that holds the light source 11, a reflector that is held in the holder 12, and a light source bracket 13 that supports the light source 11 and the holder 12. As the light source 11, a halogen lamp, a metal halide lamp, a high-pressure mercury lamp, or the like is used.

  The light source unit 10 is configured to collect the light emitted from the light source 11 with a reflector and reach the illumination unit 20.

<Lighting unit 20>
The illumination unit 20 includes an illumination bracket 26 disposed adjacent to the light source bracket 13 and an optical element group held by the illumination bracket 26.

  FIG. 3 is a perspective view of the optical element group of the illumination unit 20 and the image generation unit 30. As shown in FIG. 3, the optical element group of the illumination unit 20 includes a color wheel 21, a light tunnel 22, two relay lenses 23, a cylinder mirror 24, and a concave mirror 25.

  The color wheel 21, the light tunnel 22, the two relay lenses 23, and the cylinder mirror 24 are arranged in the order in which the light La from the light source unit 10 is incident. The concave mirror 25 is disposed so as to reflect the reflected light from the cylinder mirror 24 toward the image generation unit 30.

  As shown in FIG. 2, the illumination bracket 26 is provided with an illumination cover 27 that covers the color wheel 21 and the light tunnel 22. The illumination bracket 26 is provided with an OFF light plate 28.

  As shown in FIG. 3, the color wheel 21 has a disk shape and is configured to be fixed to the motor shaft of the color wheel motor 21a and rotate. The color wheel 21 is provided with filters such as R (red), G (green), and B (blue) in the rotation direction.

  The color wheel 21 reaches the circumferential end thereof with light La (white light) emitted from the light source unit 10 and rotates, so that the light La is time-divisionally converted into R, G, and B light Lb. The separated light Lb is emitted to the light tunnel 22.

  The light tunnel 22 has a rectangular tube shape, and the inner peripheral surface thereof is a mirror surface. The light tunnel 22 is configured to emit light Lb incident from the color wheel 21 toward the two relay lenses 23 while making the surface Lb a uniform surface light source while reflecting the light Lb a plurality of times on the inner peripheral surface.

  The two relay lenses 23 are configured to transmit the light Lb incident from the light tunnel 22 and emit the light Lb toward the cylinder mirror 24.

  The cylinder mirror 24 is configured to reflect the light Lb incident through the two relay lenses 23 toward the concave mirror 25.

  The concave mirror 25 is configured to reflect the light Lb reflected by the cylinder mirror 24 toward the image generation unit 30.

<Image generation unit 30>
As shown in FIG. 3, the image generation unit 30 includes a DMD 31 (Digital Mirror Device) that is an image generation element disposed in the reflection optical path of the concave mirror 25 and a DMD board 32 on which the DMD 31 is mounted. The DMD board 32 is provided with a heat sink 33 disposed on the opposite side of the DMD 31 to dissipate heat. Furthermore, the DMD board 32 is provided with a fixing plate 34 that presses the heat sink 33 against the DMD 31 and fixes it to the DMD board 32.

  The DMD board 32 is provided with a drive circuit that drives the DMD 31 based on the image data. The DMD 31 is driven by this drive circuit to generate video light Lc based on image data using the light Lb reflected by the concave mirror 25. Further, the DMD 31 is configured to reflect the generated video light Lc toward the projection optical system unit 40.

  The configuration of the DMD 31 will be described more specifically. An image generation surface is formed on the DMD 31. A large number of movable micromirrors are arranged in a lattice pattern on the image generation surface. Each micromirror can tilt the mirror surface by a predetermined angle around the twist axis, and can have two states of “ON” and “OFF”. When the micromirror is “ON”, the light Lb reflected by the concave mirror 25 is reflected toward the projection optical system unit 40 as video light Lc. Further, the micromirror is configured to reflect the light Lb reflected by the concave mirror 25 toward the OFF light plate 28 (see FIG. 2) when it is “OFF”. Therefore, the DMD 31 controls the emission of the light Lb for each pixel of the image data by individually driving each micromirror by the drive circuit, and generates the video light Lc.

<Projection optical system unit 40>
FIG. 4 is a schematic side view of the optical engine 100 viewed from the light source 11 side. As shown in FIG. 4, the projection optical system unit 40 includes a projection lens unit 41, a folding mirror 42 arranged on the output side of the projection lens unit 41, and a curved mirror 43 arranged facing the folding mirror 42. Prepare.

  The projection lens unit 41 is configured to transmit the video light Lc incident from the image generation unit 30, and expand and emit it toward the folding mirror 42.

  The folding mirror 42 is configured to emit the image light Lc incident from the projection lens unit 41 toward the curved mirror 43.

  The curved mirror 43 is configured to reflect and project the image light Lc incident from the folding mirror 42 onto the projection surface 101.

  The projection lens unit 41 is held by a lens holder 44 shown in FIG. The lens holder 44 is fixed to the illumination bracket 26. The projection lens unit 41 is covered with a mirror holder 45. The mirror holder 45 is fixed to the lens holder 44.

  As shown in FIG. 2, both sides of the folding mirror 42 are held by the mirror bracket 46. The mirror bracket 46 is held by a mirror holder 45. The curved mirror 43 is held by a free mirror bracket 47. The free mirror bracket 47 is held by the mirror holder 45.

  Between the folding mirror 42 and the free mirror bracket 47, a transmissive glass 48 for dust-proofing the optical system components in the image projector main body 2 is disposed. Both sides of the transmissive glass 48 are held by the mirror bracket 46.

  Next, a specific configuration of the lighting unit 20 according to the present embodiment will be described with reference to FIGS. 5 and 6. FIG. 5 is a schematic perspective view of the illumination unit 20 in FIG. 2 viewed from the back side. 6 is a cross-sectional view of a portion A in FIG.

  As shown in FIG. 5, the illumination unit 20 includes an optical element group (a light tunnel 22, two relay lenses 23, a cylinder mirror 24, and a concave mirror 25). The optical element groups 22 to 25 form light Lb (optical path) that guides light La from the light source 11 (see FIG. 2) to the DMD 31 as shown in FIG. The light tunnel 22 is an optical element that adjusts the position of the optical path Lb.

  Further, the illumination unit 20 includes an illumination bracket 26 that holds the optical element groups 22 to 25. The illumination bracket 26 is formed in a box shape so as to accommodate the optical element groups 22 to 25, and the side surface is opened. An image generation unit 30 (see FIG. 3) is fixed below the bottom wall 261 of the lighting bracket 26. The bottom wall 261 is provided with an irradiation through hole 26a for exposing the DMD 31.

  Further, the illumination bracket 26 includes three support portions (a cylinder mirror first support portion 262, a cylinder mirror second support portion 263, and a cylinder mirror third support portion 264) that support the cylinder mirror 24 at three points while being separated from the surroundings. ) Are integrally molded.

  The cylinder mirror first support portion 262 is integrally formed with the bottom wall 261 of the illumination bracket 26. The cylinder mirror first support portion 262 is formed in a column shape and supports one side of the cylinder mirror 24. This will be specifically described below with reference to FIG.

  As shown in FIG. 6, in the cylinder mirror first support portion 262, a notch 2621 is provided on a side surface 262 a on one side of the cylinder mirror 24. One end of a spring 2622 is fixed to the lower surface 2621 b of the notch 2621. The other end of the spring 2622 presses one side of the lower surface 24 a (non-reflective surface) of the cylinder mirror 24 and presses one side of the upper surface 24 b (reflective surface) against the upper surface 2621 a of the notch 2621.

  That is, the cylinder mirror first support portion 262 supports one side of the cylinder mirror 24 by pressing one side of the cylinder mirror 24 against the upper surface 2621 a of the notch 2621 using the spring force of the spring 2622.

  As shown in FIG. 5, the cylinder mirror second support portion 263 and the cylinder mirror third support portion 264 are each formed in a columnar shape, and support both corners on the other side on the lower surface 24 a of the cylinder mirror 24. Further, the third cylinder mirror support portion 264 is integrally formed with the bottom wall 261 of the illumination bracket 26.

  The illumination bracket 26 includes three support portions (a concave mirror first support portion 265, a concave mirror second support portion 266, and a concave mirror third support portion 267) that support the concave mirror 25 at three points so as to be separated from the surroundings. ) Are integrally molded.

  The concave mirror first support portion 265 and the concave mirror second support portion 266 are integrally formed on the bottom wall 261 of the illumination bracket 26. The concave mirror first support portion 265 and the concave mirror second support portion 266 support both corners on one side of the lower surface 25a (reflection surface) of the concave mirror 25.

  The concave mirror third support portion 267 is formed in a columnar shape, and supports one corner portion on the other side of the lower surface 25 a of the concave mirror 25.

  Next, the holding structure of the light tunnel 22 according to the present embodiment will be described with reference to FIG. FIG. 7 is a cross-sectional view of the light tunnel 22 holding structure as viewed from the incident side. The light tunnel 22 is formed in a square tube shape. The light tunnel 22 adjusts the position of the light Lb (optical path) that guides the light La from the light source 11 (see FIG. 2) to the DMD 31 as shown in FIG. Further, the light tunnel 22 is held by the illumination bracket 26 so that the light Lb is appropriately irradiated onto the DMD 31.

  The holding structure of the light tunnel 22 includes a first sandwiching portion 221 that sandwiches the left and right side surfaces 22a and 22b that are one opposing surface of the light tunnel 22, and an upper and lower surfaces 22c and 22d that are the other opposing surfaces of the light tunnel 22. And a second clamping part 222 for clamping.

  The first clamping unit 221 is fixed to the illumination bracket 26 by clamping the left and right side surfaces 22 a and 22 b of the light tunnel 22.

  The first clamping unit 221 includes a first adjustment screw 2211 that is screwed into the illumination bracket 26 and presses the emission side of the left side surface 22 a of the light tunnel 22. Further, the first clamping portion 221 has a plate spring 2212 (one side) fixed to the lighting bracket 26 and the other side (the other side) pressed against the incident side of the right side surface 22b of the light tunnel 22 by a spring force. A holding member). A first pressing portion 2212 a that presses the right side surface 22 b of the light tunnel 22 with a spring force is formed on the other end side of the leaf spring 2212.

  The first clamping part 221 is configured such that the clamping forces Fa and Fb of the left and right side surfaces 22a and 22b of the light tunnel 22 can be adjusted by loosening or tightening the first adjustment screw 2211. Specifically, when the first adjustment screw 2211 is loosened or tightened, the pressing force Fa for pressing the left side surface 22a of the light tunnel 22 of the first adjustment screw 2211 is adjusted. Accordingly, the pressing force Fb that presses the right side surface 22b of the light tunnel 22 of the first pressing portion 2212a is adjusted.

  The second clamping part 222 is fixed to the illumination bracket 26 by clamping the upper and lower surfaces 22c, 22d of the light tunnel 22.

  The second clamping unit 222 includes a second adjustment screw 2221 that is screwed into the illumination bracket 26 and presses the emission side of the lower surface 22 d of the light tunnel 22. Further, the second sandwiching portion 222 has one end side (one side) fixed to the lighting bracket 26 and the other end side (the other side) pressed against the incident side of the upper surface 22c of the light tunnel 22 by a spring force. Is provided. A second pressing portion 2212 b that presses the upper surface 22 c of the light tunnel 22 is formed on the other end side of the leaf spring 2212.

  The second clamping part 222 is configured such that the clamping forces Fc and Fd of the upper and lower surfaces 22c and 22d of the light tunnel 22 can be adjusted by loosening or tightening the second adjustment screw 2221. Specifically, the pressing force Fd for pressing the lower surface 22d of the light tunnel 22 of the second adjustment screw 2221 is adjusted by loosening or tightening the second adjustment screw 2221. Accordingly, the pressing force Fc that presses the upper surface 22c of the light tunnel 22 of the second pressing portion 2212b is adjusted.

  Further, in the second sandwiching portion 222, the pressing force Fc of the second pressing portion 2212b that presses the upper surface 22c (one side of the opposing surface) of the light tunnel 22 causes the left and right side surfaces 22a and 22b of the first sandwiching portion 221 and the light tunnel 22 to be pressed. It is larger than the friction force between. Specifically, the minimum value of the pressing force Fc of the second pressing portion 2212b is larger than the maximum value of the frictional force between the first sandwiching portion 221 and the left and right side surfaces 22a and 22b of the light tunnel 22.

  The frictional force between the first clamping part 221 and the left and right side surfaces 22a, 22b of the light tunnel 22 is the frictional force between the first pressing part 2212a and the right side 22b, the first adjusting screw 2211 and the left side 22a. Is the total friction force between the two.

  The maximum value of the frictional force between the first clamping part 221 and the left and right side surfaces 22a, 22b of the light tunnel 22 is within a range in which the holding position of the light tunnel 22 can be adjusted, and the left side surface 22a of the light tunnel 22 is illuminated. This is the frictional force when being farthest from the bracket 26.

  The minimum value of the pressing force Fc of the second pressing portion 2212b is a pressing force Fc when the lower surface 22d of the light tunnel 22 is closest to the illumination bracket 26 within a range where the holding position of the light tunnel 22 can be adjusted. is there.

  Next, a specific configuration of the projection lens unit 41 disposed inside the optical engine 100 according to the present embodiment will be described with reference to FIGS. 8 and 9. FIG. 8 is a front view of the projection lens unit 41. FIG. 9 is a longitudinal sectional view of FIG.

  The projection lens unit 41 includes a plurality of projection lenses 411a to 411j and a lens barrel 412 that holds the plurality of projection lenses 411a to 411j.

  The plurality of projection lenses 411a to 411j are arranged in a line along the optical axis between the image generation unit 30 and the folding mirror 42, and transmit and enlarge the video light Lc incident from the image generation unit 30. Are emitted.

  The diameters of the projection lenses 411a to 411i arranged on the image generation unit 30 side (the incident side of the video light Lc) are larger than the diameters of the projection lenses 411j arranged on the projection plane 101 side (the emission side of the video light Lc). Is set too small.

  The lens barrel 412 includes a metal incident side lens barrel 412a that holds the projection lenses 411a to 411i on the incident side among the plurality of projection lenses 411a to 411j. Further, the lens barrel 412 includes a resin-made exit-side lens barrel 412b that holds the exit-side projection lens 411j out of the plurality of projection lenses 411a to 411j and contacts the entrance-side lens barrel 412a.

  The incident side lens barrel 412a is formed in a cylindrical shape. The diameter of the incident side barrel 412a is set smaller than the diameter of the emission side barrel 412b. Thereby, the incident side lens barrel 412a is inserted into the output side lens barrel 412b and is brought into contact with the peripheral surface thereof.

  The emission side lens barrel 412b includes an outer lens barrel 4121b that holds the projection lens 411j, and an inner lens barrel 4122b that is screwed into the outer lens barrel 4121b. An incident side lens barrel 412a is inserted into and contacted with the inner lens barrel 4122b. The outer barrel 4121b and the inner barrel 4122b are resin barrels and are formed in a cylindrical shape.

  Further, the lens barrel 412 includes a fixing portion 412c for fitting and fixing a contact portion 412d between the incident side lens barrel 412a and the inner lens barrel 4122b of the output side lens barrel 412b from the outside. The fixing portion 412c is made of metal.

  Next, the configuration of the attachment portion of the projection lens unit 41 will be described with reference to FIG. FIG. 10 is an enlarged view of a portion where the projection lens unit 41 is attached.

  The projection lens unit 41 includes a lens holder 44. The lens holder 44 includes four holding plates 441 inserted through the lens barrel 412 and four corners on the incident side surface (lower surface in FIG. 10) of the holding plate 441 via reinforcement plates 443. Leg 442.

  The holding plate 441 is formed in an annular and flat plate shape. A holding hole 441 a for inserting and holding the lens barrel 412 is provided in the central portion of the holding plate 441. The holding plate 441 is fixed to a mirror holder 45 disposed on the emission side (upper side in FIG. 10) in a state where the lens barrel 412 is inserted and held in the holding hole 441a.

  The reinforcing plate 443 is formed in a flat plate shape. The reinforcing plate 443 is fixed to the corner portion of the lower surface of the holding plate 441 by a fastening member 44a, and reinforces the corner portion.

  The four legs 442 are fixed to the illumination bracket 26 of the illumination unit 20 disposed on the incident side (lower side in FIG. 10) of the lens barrel 412. Thus, a gap S that communicates with the outside is formed between the holding plate 441 and the illumination bracket 26. In the gap S, a fixed portion 412c of the lens barrel 412 and a portion around it are arranged. That is, the gap S constitutes a ventilation portion that brings the fixing portion 412c into contact with the outside air C.

  Further, the gap S is formed in a passage shape so that the outside air C passes through the optical engine 100, and is provided so that the fixed portion 412 c of the lens barrel 412 and the surrounding portion are in contact with the outside air C. More specifically, in FIG. 10, the leg portions 442 and 442 are connected to each other between the front leg portions 442 and 442 and the rear leg portions 442 and 442 apart from the holding plate 441. A connecting plate 444 is provided. The clearance S is formed in the shape of a passage through which the outside air C passes by both the connecting plates 444 and 444.

  In addition, a concave notch 444a is formed in each of the connecting plates 444 and 444 in portions facing the fixed portion 412c of the lens barrel 412.

  In addition, a fan that generates cooling air for cooling the image projector 1 is disposed on the left side (the light source 11 side) of the gap S in FIG.

  Next, image projection processing in the image projection apparatus 1 configured as described above will be described.

  The light La from the light source unit 10 reaches the color wheel 21 of the lighting unit 20, is separated into R, G, and B light Lb in a time division manner and is emitted to the light tunnel 22. The light Lb incident on the light tunnel 22 is made a uniform surface light source, passes through the two relay lenses 23, and is emitted toward the cylinder mirror 24. The light Lb incident on the cylinder mirror 24 is reflected by the concave mirror 25 to the DMD 31 of the image generation unit 30. The light Lb reflected to the DMD 31 is reflected toward the plurality of projection lenses 411a to 411j of the projection optical system unit 40 as video light Lc based on the image data. The image light Lc incident on the plurality of projection lenses 411a to 411j is transmitted through the plurality of projection lenses 411a to 411j, is expanded, and is emitted toward the curved mirror 43 by the folding mirror 42. The image light Lc incident on the curved mirror 43 is reflected and transmitted through the transmission glass 48 and projected onto the projection surface 101.

  Next, the cooling process of the projection lens unit 41 during the image projection process will be described.

  The image light Lc generated by the image generation unit 30 strikes the lens barrel 412 when entering and transmitting the projection lenses 411a to 411i. On the other hand, the fan is driven during image projection processing. By driving the fan, the outside air C (cooling air) enters the gap S from the right side (opposite side of the fan) of the gap S, hits the fixed portion 412c of the lens barrel 412 and the surrounding portion, and the left side of the gap S (fan From the side) to the outside. The fixed portion 412c and the surrounding portion are cooled by being exposed to the outside air C, whereby the heat of the image light Lc hitting the abutting portion 412d and the surrounding portion is cooled.

  Next, a method for adjusting the holding position of the light tunnel 22 will be described. At this time, in the light tunnel 22, the left and right side surfaces 22a and 22b of the light tunnel 22 are clamped to the limit by the first clamping unit 221, and the upper and lower surfaces 22c and 22d of the light tunnel 22 are clamped to the limit by the second clamping unit 222. Yes.

  As described above, the pressing force Fc of the second clamping unit 222 is larger than the frictional force between the first clamping unit 221 and the left and right side surfaces 22a and 22b of the light tunnel 22. Therefore, even if the pressing force Fc of the second clamping part 222 is weakened to the limit, the clamping force Fc, Fd of the second clamping part 222 is between the first clamping part 221 and the left and right side surfaces 22a, 22b of the light tunnel 22. It is larger than the friction force.

  Therefore, the operator moves the light tunnel 22 up and down by loosening or tightening the second adjusting screw 2221 to weaken or strengthen the pressing force Fc (clamping force Fc, Fd) of the second clamping unit 222. Thus, the holding position of the light tunnel 22 is adjusted.

  Next, effects of the lighting unit 20 according to the present embodiment will be listed and described.

(1) The illumination unit 20 of the present embodiment includes optical element groups 22 to 25 that form an optical path Lb that guides light La from the light source 11 to the DMD 31, and an illumination bracket 26 that holds the optical element groups 22 to 25. Prepare. Further, in the illumination unit 20 of the present embodiment, the cylinder mirror 24 among the optical element groups 22 to 25 is supported by the support portions 262 to 264 integrally formed with the illumination bracket 26 and is held by the illumination bracket 26. . Furthermore, in the illumination unit 20 of the present embodiment, the concave mirror 25 of the optical element groups 22 to 25 is supported by the support portions 265 to 267 integrally formed with the illumination bracket 26 and is held by the illumination bracket 26. .

  Thereby, since the cylinder mirror 24 and the concave mirror 25 are directly held by the illumination bracket 26 without using a separate member, positional errors of the cylinder mirror 24 and the concave mirror 25 in the optical element groups 22 to 25 are suppressed. Therefore, the illumination unit 20 of the present embodiment can suppress position errors of the optical element groups 22 to 25 with respect to the DMD 31. As a result, it is possible to suppress the position of the optical path Lb from being deviated from the design value, and it is possible to suppress a decrease in the irradiation efficiency for the DMD 31. Therefore, the illumination unit 20 of the present embodiment can suppress a decrease in the luminance of the video light Lc generated by the DMD 31.

(2) Moreover, the illumination unit 20 of the present embodiment is supported by the support portions 262 to 264 and held by the illumination bracket 26 in a state where the cylinder mirror 24 is separated from the surroundings. Furthermore, the illumination unit 20 of the present embodiment is supported by the support portions 265 to 267 and held by the illumination bracket 26 with the concave mirror 25 being separated from the surroundings.

  Thereby, since the cylinder mirror 24 and the concave mirror 25 are directly held only by the illumination bracket 26, position errors of the cylinder mirror 24 and the concave mirror 25 in the optical element groups 22 to 25 are further suppressed. Therefore, the illumination unit 20 of the present embodiment can further suppress the positional errors of the optical element groups 22 to 25 with respect to the DMD 31. As a result, it is possible to further suppress the position of the optical path Lb from being deviated from the design value, and to further suppress a decrease in irradiation efficiency with respect to the DMD 31. Therefore, the illumination unit 20 according to the present embodiment can further suppress a decrease in luminance of the video light Lc generated by the DMD 31.

(3) Moreover, in the illumination unit 20 of this Embodiment, the light tunnel 22 which is an optical element which can adjust the position of the optical path Lb is contained in the optical element groups 22-25.

  Therefore, by adjusting the position of the light tunnel 22 and adjusting the position of the optical path Lb, it becomes possible to guide the light La from the light source 11 to the entire DMD 31 and further suppress the decrease in the irradiation efficiency to the DMD 31. it can. Therefore, the illumination unit 20 according to the present embodiment can further suppress a decrease in luminance of the video light Lc generated by the DMD 31.

(4) Moreover, since the optical engine 100 of this Embodiment is provided with the illumination unit 20, since the fall of the irradiation efficiency with respect to DMD31 is suppressed, the fall of the brightness | luminance of the image light Lc produced | generated by DMD31 can be suppressed. .

(5) Furthermore, since the image projection apparatus 1 according to the present embodiment includes the illumination unit 20, it is possible to suppress a decrease in irradiation efficiency with respect to the DMD 31, and thus to suppress a decrease in luminance of the video light Lc generated by the DMD 31. it can.

  In the illumination unit 20 according to the present embodiment, both the cylinder mirror 24 and the concave mirror 25 are supported by a support unit integrally formed with the illumination bracket 26. However, at least one optical element in the optical element group is supported. What is necessary is just to make it support to a support part. For example, in the illumination unit 20 according to the present embodiment, the cylinder mirror 24 or the concave mirror 25 may be supported by a support unit integrally formed with the illumination bracket 26.

  Next, effects of the holding structure of the light tunnel 22 of the present embodiment will be listed and described.

(1) In the holding structure of the light tunnel 22 according to the present embodiment, the pressing force Fc that presses the upper surface 22c of the light tunnel 22 of the second holding part 222 is applied to the left and right side surfaces 22a of the first holding part 221 and the light tunnel 22. It is larger than the frictional force between 22b. As a result, the operator can adjust the holding position by moving the light tunnel 22 following the adjustment operation only by adjusting the holding forces Fc and Fd of the second holding unit 222.

  Therefore, the operator does not need to pick the light tunnel 22 and adjust the holding position, and does not need to adjust the holding position from the beginning by temporarily removing the light tunnel 22 from the lighting bracket 26 and reattaching it to the lighting bracket 26. Therefore, the holding structure of the light tunnel 22 according to the present embodiment can efficiently adjust the holding position of the light tunnel 22.

(2) Further, in the holding structure of the light tunnel 22 of the present embodiment, the second holding part 222 includes a plate spring 2212 that presses the upper surface 22c of the light tunnel 22 with a spring force, and the second holding part 222 is pressed. As the pressure Fc, the spring force of the leaf spring 2212 was used.

  In other words, the holding structure of the light tunnel 22 according to the present embodiment can easily set the pressing force Fc of the second clamping unit 222 only by setting the spring force of the leaf spring 2212. For this reason, the cost concerning the setting of the pressing force Fc of the 2nd clamping part 222 is held down. Therefore, the holding structure of the light tunnel 22 according to the present embodiment can efficiently adjust the holding position of the light tunnel 22 while reducing the cost.

(3) Further, in the holding structure of the light tunnel 22 according to the present embodiment, the pressing members of the first holding part 221 and the second holding part 222 are shared by one leaf spring 2212. For this reason, the cost concerning manufacture of the 1st clamping part 221 and the 2nd clamping part 222 is held down. Therefore, the holding structure of the light tunnel 22 according to the present embodiment can further reduce the cost and efficiently perform the adjustment operation of the holding position of the light tunnel 22.

(4) Since the illumination unit 20 of the present embodiment includes the light tunnel 22 holding structure, it is possible to efficiently adjust the holding position of the light tunnel 22, so that the irradiation position of the DMD 31 can be adjusted. Adjustment work can be performed efficiently.

(5) Since the optical engine 100 according to the present embodiment includes the light tunnel 22 holding structure, the adjustment operation of the holding position of the light tunnel 22 can be performed efficiently. Can be efficiently performed.

(6) Since the image projection apparatus 1 according to the present embodiment includes the holding structure for the light tunnel 22, it is possible to efficiently adjust the holding position of the light tunnel 22. Position adjustment work can be performed efficiently.

  In the holding structure of the light tunnel 22 according to the present embodiment, the pressing force Fc of the second clamping unit 222 is larger than the frictional force between the first clamping unit 221 and the light tunnel 22, The frictional force may be reversed. That is, the pressing force Fb of the first clamping unit 221 may be larger than the frictional force between the second clamping unit 222 and the upper and lower surfaces 22c and 22d of the light tunnel 22. Specifically, the minimum value of the pressing force Fb of the first clamping unit 221 is set larger than the maximum value of the frictional force between the second clamping unit 222 and the upper and lower surfaces 22c, 22d of the light tunnel 22. In this case, the operator loosens or tightens the first adjusting screw 2211 to weaken or increase the pressing force Fb (clamping force Fa, Fb) of the first clamping part 221 to move the light tunnel 22 left and right. Move to adjust the holding position of the light tunnel 22.

  In the light tunnel 22 holding structure of the present embodiment, the first adjusting screw 2211 presses the left side surface 22a of the light tunnel 22, and the first pressing portion 2212a of the leaf spring 2212 presses the right side surface 22a of the light tunnel 22. I tried to press. However, the pressing positions of the first adjustment screw 2211 and the first pressing portion 2212a may not be limited to the present embodiment, and may be reversed depending on the shape of the lighting bracket 26.

  Further, in the light tunnel 22 holding structure of the present embodiment, the second adjustment screw 2221 presses the lower surface 22d of the light tunnel 22, and the second pressing portion 2212b of the leaf spring 2212 presses the upper surface 22c of the light tunnel 22. I did it. However, the pressing positions of the second adjustment screw 2221 and the second pressing portion 2212b may not be limited to the present embodiment, and may be reversed according to the shape of the lighting bracket 26.

  Next, effects of the optical engine 100 according to the present embodiment will be listed and described.

(1) The optical engine 100 according to the present embodiment includes a plurality of projection lenses 411a to 411j and a lens barrel 412 that transmit and emit video light Lc generated by the image generation unit 30 with light from the light source 11. Has been placed. The optical engine 100 is provided with a gap S (ventilation part) for bringing the lens barrel 412 into contact with the outside air C.

  As a result, the lens barrel 412 contacts the outside air C through the gap S and is cooled. For this reason, even if the image light Lc strikes the lens barrel 412, the heat of the image light Lc is cooled by the lens barrel 412. Therefore, the projection lens unit 41 of the present embodiment can suppress the lens barrel 412 from being heated by the image light Lc.

  Further, the optical engine 100 according to the present embodiment can suppress the lens barrel 412 from being heated, thereby suppressing the lens barrel 412 from thermally expanding and shifting the positions of the projection lenses 411a to 411j. A decrease in the quality of the light Lc can be suppressed.

(2) Further, in the optical engine 100 of the present embodiment, the gap S is formed in a passage shape so that the outside air C passes through the inside of the optical engine 100 so that the lens barrel 412 contacts the outside air C. ing.

  Thereby, the lens barrel 412 is applied to the outside air C passing through the gap S and is efficiently cooled. Therefore, the heat of the image light Lc hitting the lens barrel 412 is efficiently cooled by the lens barrel 412. Therefore, the optical engine 100 according to the present embodiment can efficiently suppress the lens barrel 412 from being heated by the image light Lc.

(3) Further, in the optical engine 100 of the present embodiment, the lens barrel 412 includes a metal incident side lens barrel 412a and a resin emission side lens barrel 412b.

  As a result, the heat of the image light Lc striking the incident side lens barrel 412a is released from the incident side lens barrel 412a to the outside, so that the heat of the image light Lc is efficiently released. Therefore, the optical engine 100 according to the present embodiment can further prevent the lens barrel 412 from being heated by the image light Lc.

  Further, since the diameter of the incident side lens barrel 412a is smaller than the diameter of the output side lens barrel 412b, the incident side lens barrel 412a is hotter than the output side lens barrel 412b. Therefore, by using a metal barrel for the incident side barrel 412a, it is possible to reliably suppress the incidence side barrel 412a from becoming hot. Further, by using a resin-made lens barrel for the exit-side lens barrel 412b that is not easily heated, the cost and weight of the lens barrel 412 can be reduced.

  Further, the optical engine 100 of the present embodiment includes a fixing portion 412c that fixes a contact portion 412d between the incident side barrel 412a and the emission side barrel 412b, and the gap S causes the fixing portion 412c to contact the outside air C. It is provided as follows.

  The abutting portion 412d is a portion that hardly dissipates heat because the metal and the resin are in abutment. For this reason, it cools when the fixing | fixed part 412c contacts outside air C, and the heat of the contact part 412d is cooled by this. Therefore, the optical engine 100 of the present embodiment can further suppress the lens barrel 412 from being heated by the image light Lc.

(4) In addition, the optical engine 100 of the present embodiment includes a lens holder 44 through which the lens barrel 412 is inserted and held. The lens holder 44 is fixed to the illumination unit 20 by forming a gap S between the lens holder 44 and the illumination unit 20 disposed on the incident side of the lens barrel 412, and the gap S forms a ventilation portion.

  As a result, the optical engine 100 according to the present embodiment can simply configure the ventilation portion to cool the heat of the image light Lc hitting the lens barrel 412. Therefore, the optical engine 100 according to the present embodiment can suppress the cost and prevent the lens barrel 412 from being heated by the image light Lc.

(5) Further, in the optical engine 100 according to the present embodiment, the notches 444a are provided in portions of the coupling plates 444 and 444 facing the fixing portion 412c of the lens barrel 412. As a result, the fixed portion 412c is exposed, so that the area in contact with the outside air C is increased, and the outside air C is more efficiently cooled. Therefore, the heat of the contact portion 412d is efficiently cooled. Therefore, the optical engine 100 of the present embodiment can further suppress the lens barrel 412 from being heated by the image light Lc.

(6) Moreover, since the image projection apparatus 1 of this Embodiment is provided with the optical engine 100, it can suppress that the lens barrel 412 heats up with the image light Lc, Therefore The position of each projection lens 411a-411j has shifted | deviated. There is no end. Therefore, the image projection apparatus 1 according to the present embodiment can suppress deterioration in quality such as the sharpness of the video light Lc.

  In the optical engine 100 according to the present embodiment, the passage-shaped gap S is provided as a ventilation portion. Alternatively, the ventilation portion may be provided so that the lens barrel 412 is exposed to the outside.

DESCRIPTION OF SYMBOLS 1 Image projector 22 Light tunnel 22a Left side surface 22b Right side surface 22c Upper surface 22d Lower surface 26 Illumination bracket 100 Optical engine 221 1st clamping part 222 2nd clamping part 2212 Leaf spring (pressing member)
Fc pressing force

JP2013-64866A

Claims (5)

A first sandwiching portion that is fixed to the lighting bracket by sandwiching one opposing surface of the rectangular tubular light tunnel, and the clamping force of the one opposing surface is adjustable;
A second clamping part that is fixed to the illumination bracket by sandwiching the other facing surface of the light tunnel and capable of adjusting the clamping force of the other facing surface;
The pressing force that presses one side of the opposing surface of one of the first clamping unit or the second clamping unit is based on the frictional force between the other of the first clamping unit or the second clamping unit and the opposing surface. Light tunnel holding structure characterized by its large size. The light tunnel holding structure according to claim 1,
One of the first clamping part or the second clamping part includes a pressing member that presses one side of the facing surface with a spring force, and the pressing force uses a spring force of the pressing member. Characteristic light tunnel holding structure. A first sandwiching portion that is fixed to the lighting bracket by sandwiching one opposing surface of the rectangular tubular light tunnel and that can adjust the clamping force of the one opposing surface, and the other opposing surface of the light tunnel A lighting unit including a second clamping unit fixed to the lighting bracket and capable of adjusting a clamping force of the other facing surface;
The pressing force that presses one side of the opposing surface of one of the first clamping unit or the second clamping unit is based on the frictional force between the other of the first clamping unit or the second clamping unit and the opposing surface. The lighting unit is also characterized by its large size. A first sandwiching portion that is fixed to the lighting bracket by sandwiching one opposing surface of the rectangular tubular light tunnel and that can adjust the clamping force of the one opposing surface, and the other opposing surface of the light tunnel An optical engine comprising a second clamping unit fixed to the lighting bracket and capable of adjusting a clamping force of the other facing surface;
The pressing force that presses one side of the opposing surface of one of the first clamping unit or the second clamping unit is based on the frictional force between the other of the first clamping unit or the second clamping unit and the opposing surface. An optical engine characterized by its large size. A first sandwiching portion that is fixed to the lighting bracket by sandwiching one opposing surface of the rectangular tubular light tunnel and that can adjust the clamping force of the one opposing surface, and the other opposing surface of the light tunnel An image projection apparatus comprising: a second clamping unit fixed to the illumination bracket and capable of adjusting a clamping force of the other facing surface;
The pressing force that presses one side of the opposing surface of one of the first clamping unit or the second clamping unit is based on the frictional force between the other of the first clamping unit or the second clamping unit and the opposing surface. An image projection apparatus characterized by being large.