JP4714431B2 - Projection lens device and projector device - Google Patents

Description

  The present invention relates to a projection lens device that projects light and a projector device including the same.

Conventionally, in this type of projection lens apparatus, the aperture amount is variable in the optical path of the projection light passing through the projection optical system so that the contrast of the projection image can be varied according to the brightness around the screen. A configuration provided with a possible diaphragm device is known. In this configuration, the diaphragm device is interposed in the optical path of the projection optical system, so that light other than the projection light emitted from the display element, that is, for example, the projection light is reflected by the inner surface of the lens barrel or the like. It is considered that the contrast of the projected image is improved as a result of the non-reflected light, which is stray light, being blocked by the diaphragm device (see, for example, Patent Document 1).
JP 2004-157348 A (page 6-7, FIG. 2)

  However, in such a projection lens device, the aperture amount and the contrast height are not necessarily in a relative relationship. For example, when the aperture amount is increased by the aperture device in order to improve the contrast, the projected image becomes darker than the effect of improving the contrast. Thus, there is a problem that if the aperture amount is reduced, the contrast cannot be improved.

  The cause of this is that if the aperture plate of the aperture stop device is largely moved into the optical path to increase the aperture amount and increase the amount of non-reflected light, the amount of light that is projected is also increased. It is considered that if the amount of light entering the optical path of the diaphragm plate of the diaphragm device is reduced, the non-reflected light is not sufficiently shielded and the contrast cannot be improved.

  SUMMARY An advantage of some aspects of the invention is that it provides a projection lens device capable of improving contrast without darkening a projected image and a projector device including the projection lens device.

The projection lens apparatus according to claim 1 is a projection lens apparatus of a projector apparatus that projects light, and is a projection optical system that includes a movable lens barrel that is movable along the optical axis direction and performs a zoom operation by this movement. And an aperture device that includes a plurality of apertures along the optical axis direction, can block stray light, and adjusts the amount of light that passes through the projection optical system, and changes the amount of light regulated by the aperture device A diaphragm driving means, and the diaphragm device is capable of moving in the optical axis direction integrally with the movable lens barrel, and the projection light passing through one diaphragm body located on the front side in the optical axis direction, The other diaphragms located behind the diaphragm in the optical axis direction are arranged so as not to block light.

An aperture device that can move in the optical axis direction integrally with a moving lens barrel that performs a zoom operation by moving along the optical axis direction is provided with a plurality of apertures in the optical axis direction. The stray light that is not shielded by the one stop disposed on the front side is shielded by the other stop disposed on the rear side in the optical axis direction, so that the contrast is improved and the stray light positioned on the front side in the optical axis direction is improved. Since the projection light passing through the diaphragm is not shielded by other diaphragms located on the rear side in the optical axis direction, the projection image is prevented from becoming dark.

  A projection lens device according to a second aspect is the projection lens device according to the first aspect, wherein the diaphragm is formed in an arc shape protruding toward the optical axis side.

  Then, by forming the diaphragm in an arc shape protruding toward the optical axis side, stray light is effectively shielded and the contrast is improved.

  The projector device according to claim 3 is a light source, a light modulation unit that modulates light from the light source, and a projection lens device according to claim 1 or 2 that projects the light modulated by the light modulation unit onto a screen. Is provided.

  Then, by using the projection lens device according to claim 1 or 2, stray light that has not been shielded by one diaphragm disposed on the front side in the optical axis direction is another diaphragm body disposed on the rear side in the optical axis direction. Therefore, the contrast is improved, and the projection light passing through one aperture located on the front side in the optical axis direction is not shielded by the other aperture located on the rear side in the optical axis direction. It is prevented from becoming dark.

  According to a fourth aspect of the present invention, in the projector device according to the third aspect, the light modulation means reflects the light from the light source to the projection lens device when turned on, and reflects the light in a direction different from that when turned on when turned off. It is a reflection type element, and the diaphragm device is arranged on the side where the light is reflected when the optical axis is turned off.

  By disposing the diaphragm on the side where the light is reflected when the light modulation means is off with respect to the optical axis, stray light is more reliably blocked by the diaphragm and the contrast is improved.

  According to the present invention, contrast can be improved without darkening a projected image.

  Hereinafter, the configuration of a projection lens device according to an embodiment of the present invention will be described with reference to FIGS.

  In FIG. 8, reference numeral 1 denotes a projector apparatus. The projector apparatus 1 includes a lamp 2 as a light source, a color wheel unit 4 having a color wheel 3 for coloring light emitted from the lamp 2, and the color wheel unit 4. Illumination optical system 5 that uniformly guides the illuminance of the colored light, and a display element as a light modulation means for modulating the light guided by the illumination optical system 5, that is, a DMD (Digital Micromirror Device (trade name) )) 6 and a lens barrel 7 as a projection optical system for projecting the light beam modulated by the DMD 6 onto a screen (not shown). The projector apparatus 1 includes an illumination optical system 5 and a DMD 6 attached to a frame body 8 as a main body, and is housed in an exterior housing (not shown) together with the lamp 2, the color wheel unit 4, the lens barrel 7, and the like. Has been.

  In the following, along the optical axis O of the light beam traveling from the lamp 2 to the screen, the screen side is the front side, the lamp 2 side is the rear side, and the left-right direction from the rear side to the front side of the optical axis O is the left-right direction. explain.

  The lamp 2 is an incandescent bulb such as a halogen lamp or a discharge lamp such as a metal halide lamp.

  The color wheel 3 is formed, for example, in a disk shape in which each color filter of red (R), green (G), and blue (B) is provided in an equally divided fan shape, and in a direction substantially orthogonal to the optical axis O. Are arranged along. The color wheel unit 4 moves the color wheel 3 at a constant speed in the circumferential direction so that the red (R), green (G), and blue (B) color filters of the color wheel 3 sequentially strike the light rays of the lamp 2. The light beam emitted from the lamp 2 is rotated and colored in each color in a time-sharing manner.

  The illumination optical system 5 includes a light tube 11 that uniformizes the illuminance of the light beam colored by the color wheel unit 4, a lens unit 12 that condenses the light beam that has been uniformed by the light tube 11, and the lens unit 12 collects the light beam. A reflection mirror M1 that reflects the emitted light beam, a cone-cave mirror M2 that reflects the light beam reflected by the reflection mirror M1 to the DMD 6, and the like are provided.

  The light tube 11 is arranged coaxially with the optical axis O. This light tube 11 is for irradiating the lens unit 12 while making the illuminance of the light colored by the color wheel unit 4 uniform.

  The lens unit 12 includes lenses L1, L2, and L3 arranged along the optical axis O.

  The reflection mirror M1 is inclined with respect to the axial direction of the lens unit 12, and is disposed so as to reflect light toward the cone-cave mirror M2.

  The cone-cave mirror M2 is formed in a substantially square shape when viewed from the front, has a conical reflection surface, and is disposed below the lens barrel 7 so as to face the DMD 6. The cone-cave mirror M2 is formed with a notch 13 having a rectangular shape in front view, into which the rear part of the lens barrel 7 is fitted, at the corner.

  The DMD 6 is a reflective element that modulates and reflects the light rays collected by the lenses L1, L2, L3, etc. according to the processed video signal, such as a video signal processing circuit that processes the video signal. Implemented in electronic circuits. Specifically, the DMD 6 has a large number of minute mirrors (not shown) in a matrix, and these mirrors are turned on / off, that is, switched, and reflect light to the lens barrel 7 when turned on (on light (projection light)). When off, light is reflected in the upper right direction of the optical axis O, which is a direction different from the reflection direction when on (off light (non-projection light)).

  The lens barrel 7 includes a substantially cylindrical focus ring 15 and a substantially cylindrical zoom ring 16 each holding a plurality of lenses therein, and is attached to the frame body 8 via a lens barrel holding plate 17. Yes.

  The focus ring 15 has a rear portion inserted into the zoom ring 16 and is provided to be rotatable around the optical axis O. Further, as shown in FIG. 5, a convex lens L4, a biconcave lens L5, a concave meniscus lens L6, a convex lens L7, and a concave meniscus lens L8 are sequentially provided in the focus ring 15 from the rear side to the front side in the optical axis direction. Is retained. The focus ring 15 is rotated to move the lens located in the forefront portion back and forth along the optical axis O with respect to the zoom ring 16, thereby performing a focusing operation.

  The zoom ring 16 is provided so as to be rotatable around the optical axis O independently of the focus ring 15 and holds the front portion of the cylindrical movable lens barrel 18 inside. In the zoom ring 16, a biconcave lens L9, a concave meniscus lens L10, a biconvex lens L11, and a convex lens L12 are sequentially held from the rear side to the front side in the optical axis direction.

  In addition, the movable lens barrel 18 is provided to be movable in the front-rear direction along the optical axis direction in conjunction with the rotation of the zoom ring 16. By moving in the front-rear direction, the magnification of the projected image is changed to zoom. A concave meniscus lens L13, a convex lens L14, a biconcave lens L15, a biconvex lens L16, and a biconvex lens L17 are sequentially held from the rear side to the front side in the optical axis direction.

  As shown in FIG. 2, the lens barrel holding plate 17 is formed in a substantially square shape when viewed from the front, and has a circular hole portion 28 through which the movable barrel 18 is inserted and protrudes into the frame body 8. Has been drilled. The lens barrel holding plate 17 is provided with screw holes 29 at the four corners, and the lens barrel holding plate 17 is attached to the frame body 8 by inserting and tightening screws (not shown) in the screw holes 29 respectively. Fixed to.

  Further, as shown in FIG. 1 and FIG. 2, the movable lens barrel 18 has a diaphragm device 31 for adjusting the amount of light passing through the lens barrel 7, and the diaphragm device 31 is driven to drive the diaphragm device 31. A diaphragm driving means 32 is provided for changing the amount of light regulated by the above. The aperture device 31, aperture drive means 32, lens barrel 7 and the like constitute a projection lens device 33.

  The aperture device 31 is provided so as to be movable integrally with the movable lens barrel 18 and is arranged on the upper right side with respect to the optical axis O. That is, the diaphragm device 31 is arranged in the reflection direction of the off-light from the DMD 6 with respect to the optical axis O. Further, the diaphragm device 31 includes a diaphragm plate 31a as a diaphragm located on the front side in the optical axis direction of the movable lens barrel 18, and a diaphragm plate 31b as a diaphragm body located on the rear side in the optical axis direction of the movable lens barrel 18. It has.

  The diaphragm plates 31a and 31b extend downward from the lower right part of the diaphragm portions 35a and 35b, and the diaphragm portions 35a and 35b projecting in an arc shape toward the center side of the movable barrel 18, that is, the optical axis side. It has supported parts 36a and 36b, and is formed in substantially the same shape. The diaphragm plate 31a is disposed in front of the biconvex lens L17 of the movable lens barrel 18 and in the rear portion of the biconcave lens L9 in the zoom ring 16, and the diaphragm plate 31b is disposed in the rear of the concave meniscus lens L13 of the movable lens barrel 18. Has been. Further, the diaphragm plates 31a and 31b are arranged so as to overlap each other when viewed along the optical axis direction, and the right portions of the supported portions 36a are connected to each other by the connection plate 37 to be integrated. .

  The diaphragm plates 31a and 31b project from a diaphragm plate support portion 38 that projects horizontally behind the large-diameter portion 18a of the movable lens barrel 18 located inside the hole 28 of the lens barrel holding plate 17. The lower ends of the supported portions 36a and 36b are pivotally supported on the pivot shaft 38a, and the diaphragm plate 31a is moved forward along the optical axis direction by a spring 39 as a diaphragm means biasing member. It is energized.

  The aperture driving means 32 is provided so as to be movable integrally with the moving barrel 18 along the optical axis direction, connected to the motor 41, the first transmission means 42 driven by the motor 41, and the first transmission means 42. The transmission means 44 provided with the second transmission means 43, and the first transmission means 42 are urged in the direction of connection to the second transmission means 43, and the first transmission means 42 is applied to the second transmission means 43. Support means 45 is provided for supporting the displacement in the connecting direction and the separating direction.

  The motor 41 pivotally supports a holding portion 46 provided in the first transmission means 42 and is fixed to an attachment frame 47 fixed to the frame body 8 so that the cone-cave mirror M2 against reflected light from the DMD 6 is fixed. Located behind the corn cave mirror M2 behind. That is, the motor 41 is disposed on the lower left side with respect to the optical axis O. In other words, the motor 41 is disposed on the opposite side of the aperture device 31 across the optical axis O, and is deviated from the position where off light is reflected.

  Here, the mounting frame 47 is fixed to the frame body 8 and has a horizontal and longitudinal board part 51 along the left-right direction, and a shaft support that is bent upward from the front and rear of the board part 51 and holds the holding part 46 from the front and rear. Plates 52 and 52 and a mounting plate 53 that is bent upward from one end on the left side of the substrate 51 and to which the motor 41 is attached. Further, an insertion hole (not shown) is formed in the mounting plate 53, and the rotation shaft 55 of the motor 41 is inserted through the insertion hole. That is, the motor 41 has the rotation shaft 55 along a direction substantially orthogonal to the optical axis O in plan view. A worm gear WG as drive transmission means is integrally provided at the tip of the rotating shaft 55.

  The worm gear WG is positioned between the shaft support plates 52 and 52 and is rotated integrally with the rotation shaft 55 of the motor 41.

  The first transmission means 42 includes a holding portion 46 that is elongated in the left-right direction, a closed-side transmission gear G1 that is a rotating gear as a closed-side transmission portion that is rotatably held by the holding portion 46, and a rotary gear A transmission gear G2, an open-side transmission gear G3 that is a rotation gear as an open-side transmission unit, and a transmission gear G4 as a rotation gear are provided and attached to the frame body 8.

  As shown in FIG. 3, the holding portion 46 includes a U-shaped frame portion 61 that is an intermediate portion in the longitudinal direction of the holding portion 46, and a plate portion that extends from the U-shaped frame portion 61 in the left-right direction. Holding arm portions 62 and 63, and is formed in a substantially V shape in a front view.

  The U-shaped frame portion 61 includes rotating plates 65 and 65 that are rotatably supported by the shaft support plates 52 and 52, and a connecting plate 66 that connects the upper portions of the rotating plates 65 and 65 to each other. The lower side is formed in a U-shape. The rotation plates 65 and 65 are provided with rotation holes 67 and 67, respectively, along the optical axis direction.

  The holding arm portions 62 and 63 are provided so as to be inclined from the front rotation plate 65 of the U-shaped frame portion 61 in the left-right direction and upward. Then, at the rear portion of the holding arm 62, shaft portions 68 and 68 on which the open-side transmission gear G3 and the transmission gear G4 are rotatably supported are projected substantially horizontally rearward along the optical axis direction. Further, shaft portions 69 and 69, on which the closed side transmission gear G1 and the transmission gear G2 are pivotally supported, are projected substantially horizontally along the optical axis direction at the rear portion of the holding arm portion 63. Yes. The closed side transmission gear G1 is positioned at one end of the holding portion 46, that is, the right end portion, which is the tip of the holding arm portion 63 by the shaft portion 69, and the open side transmission gear G3 is held by the holding arm portion 62 by the shaft portion 68. Is located at the other end of the holding portion 46, that is, the left end.

  The shaft portions 68 and 68 and the shaft portions 69 and 69 are spaced apart from each other. Further, the shaft portions 68 and 68 are separated by a distance at which the transmission gears G3 and G4 pivotally supported by the shaft portions 68 and 68 can mesh with each other. Similarly, the shaft portions 69 and 69 are separated by a distance at which the transmission gears G1 and G2 pivotally supported by the shaft portions 69 and 69 can mesh with each other.

  Therefore, as shown in FIGS. 1 and 2, the closed-side transmission gear G1 has a rotating shaft along the optical axis direction, and is held by the urging spring 71 as a closed-side transmission portion urging body. It is biased toward the front side along the 63 side, that is, along the optical axis direction. Similarly, the open-side transmission gear G3 has a rotation axis along the optical axis direction, and by the biasing spring 72 as the open-side transmission unit biasing body, on the holding arm 62 side, that is, along the optical axis direction. It is urged to the front side. Accordingly, the transmission gears G1 and G3 are given frictional force, that is, friction, to the rotation by the biasing springs 71 and 72, respectively.

  Further, the second transmission means 43 is formed in an annular shape, and the inner peripheral portion has a smooth circumferential surface, and the transmission gears G1 and G3 of the transmission means 44 are arranged on the lower half of the outer peripheral portion, respectively. A gear portion 75 that can be selectively meshed is formed in the front-rear direction.

  As shown in FIGS. 2 and 4, the second transmission means 43 has a second transmission means holding portion provided on the outer peripheral surface of the movable lens barrel 18 with the rear portion of the movable lens barrel 18 inserted therein. Held in 76. Here, the inner diameter dimension of the second transmission means 43 and the outer diameter dimension of the second transmission means holding portion 76 are such that the second transmission means 43 can smoothly rotate around the second transmission means holding portion 76. Is set to

  In addition, the front side of the second transmission means 43 is positioned by a holding step portion 77 formed in a step shape so as to have a large diameter on the front side of the second transmission means holding portion 76 of the movable barrel 18, and the movable barrel 18 The rear side is positioned by the pins 78 and 79 attached to the optical axis O, and the rear side is positioned so as not to rattle in the front-rear direction with respect to the movable barrel 18 and to be inclined with respect to the optical axis O. As a result, the second transmission means 43 has a rotation axis along the optical axis direction, and is provided to be movable back and forth along the optical axis direction as the movable lens barrel 18 moves.

  Further, as shown in FIGS. 1 and 2, etc., protrusions 81 and 82 are respectively formed on the rear side of the upper portion of the second transmission means 43 so as to extend rearward. A pin 78 is located between the projections 81 and 82, and the projection 81, 82 and the pin 78 regulate the amount of rotation of the second transmission means 43 in the rotational direction around the optical axis. That is, the pin 78 also has a function as a stopper of the second transmission means 43.

  Further, on the outer peripheral surface on the upper side of the second transmission means 43, a cam portion 85 is provided in the vicinity of the protrusion 81, that is, in the upper right portion, along the radial direction. A cam pin 86 that guides or guides the diaphragm plate 31a projects forward from the cam portion 85, and the cam pin 86 is formed in the diaphragm plate 31a from the throttle portion 35a to the supported portion 36a. It is inserted into the arcuate cam groove 87.

  As a result, the rotation of the second transmission means 43 causes the cam pin 86 to rotate in the circumferential direction of the second transmission means 43 together with the cam portion 85, so that the cam pin 86 and the cam groove 87 cause the cam pin 86 to move. The diaphragm portions 35a and 35b of the guided diaphragm plate 31a and the diaphragm plate 31b integrally connected to the diaphragm plate 31a approach or move away from the optical axis O, so that the diaphragm device 31 is opened and closed to move. The aperture amount of light passing through the lens barrel 18 is adjusted.

  The gear portion 75 of the second transmission means 43 is set such that the thickness dimension in the direction along the optical axis O is larger than the moving distance of the movable barrel 18. That is, the gear unit 75 has a gear groove longer than the moving distance of the movable lens barrel 18. Therefore, the transmission gears G1 and G3 and the second transmission means 43 can mesh with each other over the entire movement range of the movable lens barrel 18.

  The support means 45 includes both connection gears G5 and a support shaft 88 that pivotally supports the both connection gears G5 together with the holding portion 46 with respect to the mounting frame 47.

  Both connecting gears G5 are connected to a rotation hole (not shown) formed in the rotation holes 67 of the rotation plates 65 and 65 of the U-shaped frame portion 61 of the holding portion 46 and the shaft support plates 52 and 52 of the mounting frame 47. The shaft is rotatably supported by the inserted support shaft 88 and meshed with the transmission gears G2 and G4 and the worm gear WG, respectively. That is, both connection gears G5 have a rotation axis along the optical axis direction.

  Both the connection gears G5 are rotated via the worm gear WG by the rotation of the motor 41, and the transmission gears G1, G3 are rotated by rotating the transmission gears G2, G4 along with the rotation. It is intended to rotate. In other words, the two connection gears G5 are connected to the transmission gears G1 and G3 and rotated by the driving force of the motor 41. Therefore, both the connection gears G5 and the transmission gears G1 and G3 have a relationship between the sun gear and the planetary gear.

  That is, the connection gear G5 and the holding portion 46 are provided so as to freely rotate with respect to the support shaft 88, respectively.

  The frame body 8 is formed of a member such as metal, for example, and as shown in FIG. 8, the color wheel unit 4, the illumination optical system 5, the DMD 6, and the lens barrel 7 are respectively attached and held in the exterior housing. Yes.

  Next, the operation of the above embodiment will be described.

  The light emitted from the lamp 2 is colored by red (R), green (G), and blue (B) in a time-sharing manner by the color wheel 3, and after the illuminance is made uniform by the light tube 11. The light is condensed by the lens unit 12 and reflected by the reflecting mirror M1 to the cone-cave mirror M2, and the light reflected by the cone-cave mirror M2 enters the DMD 6. Further, the color light incident on the DMD 6 is reflected according to the video signal processed by the video signal processing circuit or the like, and only the on-light is reflected to the lens barrel 7 and is projected onto the screen after being subjected to focus adjustment and zoom adjustment. The At this time, each color light is synthesized as an afterimage by the viewer's vision, so that it is visualized as a color image.

  When adjusting the contrast of the image projected on the screen, when the motor 41 is rotated by an external operation or the like, the worm gear WG rotates together with the rotation of the motor 41, and both connections engaged with the worm gear WG are connected. Gear G5 rotates.

  At this time, as shown in FIG. 7 (a), when the both connecting gears G5 are rotated in the counterclockwise direction, for example, the holding portions provided from the biasing springs 71 and 72 to the transmission gears G1 and G3. Due to the friction with respect to the rotation direction of 46, the rotation of both connection gears G5 acts as a rotational force in the circumferential direction of the support shaft 88 of the holding portion 46, and the holding portion 46 also rotates counterclockwise, and both connection gears A closed transmission gear G1 that rotates around the planet G5 is connected to the gear portion 75 of the second transmission means 43.

  Then, when the second transmission means 43 is rotated in the clockwise direction by the rotation of the closed transmission gear G1, as shown by the imaginary line in FIG. Rotating clockwise about the rotation axis of 43, and by the action of the cam pin 86 and the cam groove 87, the diaphragm plates 31a, 31b rotate downward about the diaphragm plate support portion 38 to restrict the diaphragm. The device 31 is closed, and the diaphragm portions 35a and 35b project toward the optical axis O, which is the central axis of the movable lens barrel 18, so that the amount of light passing through the movable lens barrel 18 is reduced.

  On the other hand, as shown in FIG. 7 (b), when both connecting gears G5 are rotated clockwise, for example, the holding portion 46 is also rotated clockwise by the same action as that when the connecting gear G5 is rotated clockwise. The open side transmission gear G3 that moves and planetarily rotates around both connection gears G5 is connected to the gear portion 75 of the second transmission means 43.

  When the second transmission means 43 is rotated counterclockwise by the rotation of the open-side transmission gear G3, the cam pin 86 is moved together with the second transmission means 43 as shown by the solid line in FIG. Rotating counterclockwise about the optical axis O, which is the rotation axis of 43, and the diaphragm plates 31a and 31b are moved upward about the diaphragm plate support 38 by the action of the cam pins 86 and the cam grooves 87. And the diaphragm device 31 is opened, and the diaphragm portions 35a and 35b are retracted in the radial direction of the movable lens barrel 18, whereby the amount of light passing through the movable lens barrel 18 is increased.

  Further, the second transmission means 43 rotates until the pin 78 comes into contact with one of the protrusions 81 and 82 at the maximum. Here, when the motor 41 continues to rotate in a state in which one of the protrusions 81 and 82 is in contact with the pin 78, that is, in a state where the second transmission means 43 is rotated to the end of the rotation restriction range. Means that the force to rotate the closed transmission gear G1 or the open transmission gear G3 connected to the gear portion 75 of the second transmission means 43 acts as a force to rotate the holding portion 46 around the support shaft 88. The holding portion 46 rotates when the closed-side transmission gear G1 connected to the gear portion 75 of the second transmission means 43 or the open-side transmission gear G3 is rebounded away from the gear portion 75 of the second transmission means 43. Move. For this reason, transmission of the driving force of the motor 41 to the second transmission means 43 is blocked.

  Further, while the motor 41 continues to rotate, a force that rotates in the direction of connecting the open side transmission gear G1 or the closed side transmission gear G3 to the second transmission means 43 acts on the holding portion 46. The closed side transmission gear G1 or the open side transmission gear G3 once separated from the gear part 75 of the transmission means 43 is connected to the gear part 75 of the second transmission means 43 again.

  That is, by repeating these actions, the gear portion 75 of the second transmission means 43 and the transmission gears G1 and G3 are repeatedly brought into contact with and separated from each other, and the second transmission means 43 is moved to the end of the rotation restriction range. Even if the motor 41 continues to rotate, excessive force is prevented from being applied between the gear portion 75 of the second transmission means 43 and the transmission gears G1 and G3.

  Further, the off-light from the DMD 6 is reflected in the upper right direction of the optical axis O, is blocked by the diaphragm portions 35a and 35b of the diaphragm plates 31a and 31b of the diaphragm device 31, and is prevented from entering the lens barrel 7. .

  As described above, according to the embodiment, by providing the diaphragm plates 31a and 31b in the optical axis direction, the stray light that is not shielded by the diaphragm plate 31a is shielded by the diaphragm plate 31b, and thus the projected image. The stray light can be prevented from being mixed in and the contrast of the projected image can be improved, and the aperture plates 31a and 31b are arranged in substantially the same shape so as to overlap each other in the optical axis direction, thereby projecting light passing through the aperture plate 31a. Since the aperture plate 31b is not shielded from light, it is possible to prevent projection light from being shielded more than necessary and the projection image from becoming dark.

  Further, by providing the diaphragm plates 31a and 31b with arc-shaped diaphragm portions 35a and 35b protruding toward the optical axis side, the diaphragm portions 35a and 35b effectively block stray light due to the off-light of the DMD 6, Contrast can be improved.

  Further, by arranging the diaphragm plates 31a and 31b on the side where the off-light of the DMD 6 is reflected with respect to the optical axis O, stray light that passes a lot on the side on which the off-light is reflected is applied to the diaphragm plates 31a and 31b. The light can be reliably shielded and the contrast can be further improved.

  In this way, it is possible to improve the image quality of a projector apparatus using a reflective display element such as DMD6.

  In the above embodiment, the first transmission means 42 is urged in the direction of connection to the second transmission means 43, and the first transmission means 42 is displaceable in the direction of connection to the second transmission means 43 and in the direction away from it. The transmission means 42 is supported by the support means 45.

  As a result, the mounting position between the lens barrel 7 and the frame body 8, specifically, the mounting position in the height direction between the second transmission means 43 and each transmission gear G1, G3, and the motor 41 and the frame body 8 Even if the mounting position of the first transmission means deviates from the normal position, the first transmission means 42 rotates to absorb this deviation, and the second transmission means 43 and the transmission gears G1, G3 are surely connected. Since the driving force of the motor 41 is reliably transmitted to the diaphragm device 31, the diaphragm device 31 can be driven with high accuracy.

  Furthermore, the intermediate portion in the longitudinal direction of the holding portion 46 is pivotally supported so that the closed transmission gear G1 is moved to the second transmission means 43 by the rotation of the holding portion 46 when the diaphragm device 31 is driven in the closing direction. Since the opening side transmission gear G3 is connected to the second transmission means 43 by the rotation of the holding portion 46 when the diaphragm device 31 is driven in the opening direction, the first transmission means 42 is connected to the second transmission means 43. On the other hand, it can be displaced with a relatively simple configuration.

  The driving force of the motor 41 can be reliably transmitted to the expansion device 31 by configuring the closed side transmission gear G1, the open side transmission gear G3, and the second transmission means 43 by rotating gears.

  In addition, by connecting the two connection gears G5 that are rotated by the driving force of the motor 41 to the transmission gears G1 and G3, the holding portion 46 is rotated in accordance with the rotation direction of the motor 41, and the closed-side transmission gear. Since G1 and the open side transmission gear G3 are selectively connected to the second transmission means 43, the rotational force of the motor 41 is used for the rotation of the holding part 46, and the urging means for rotating the holding part 46, etc. Since it is not necessary to provide a separate layer, the configuration can be simplified.

  Further, the second transmission means 43 and the transmission gears G1 and G3 are provided so as to have respective rotation axes along the optical axis direction, and the gear groove of the gear portion 75 of the second transmission means 43 is moved to the movable lens barrel. Even if the second transmission means 43 moves along the optical axis direction as the movable lens barrel 18 moves, the second transmission means 43 and the transmission gears G1, G3 Can be reliably engaged.

  When the rotation of the second transmission means 43 is restricted, even if the closed transmission gear G1 or the open transmission gear G3 connected to the gear portion 75 of the second transmission means 43 tries to rotate, The closing side transmission gear G1 connected to the gear portion 75 of the second transmission means 43 or the open side is caused by the force to rotate the closed side transmission gear G1 or the open side transmission gear G3. The transmission gear G3 acts as a force that rotates in a direction away from the gear portion 75 of the second transmission means 43 and escapes, and the transmission of the driving force of the motor 41 to the second transmission means 43 is cut off, and the closed side transmission It is possible to prevent an excessive force from being applied between the gear G1 or the open side transmission gear G3 and the second transmission means 43.

  In addition, since the projector device 1 includes the projection lens device 33, the contrast can be improved without darkening the projected image, the usability and the reliability can be improved, and the driving force of the motor 41 can be reliably transmitted to the aperture device 31. Since the diaphragm device 31 can be driven with high accuracy, the contrast of the projected image can be changed with high accuracy, and the image quality of the projector device 1 can be improved.

  Further, by providing the motor 41 on the side opposite to the side where the light is reflected by the DMD 6 when the optical axis O is off, it is possible to prevent the motor 41 from being heated by the light reflected by the DMD 6 when off.

  Moreover, since the motor 41 is disposed behind the cone-cave mirror M2, the ON light from the DMD 6 is not irradiated to the motor 41, and the motor 41 can be prevented from being heated by the ON light. .

  Further, by attaching the motor 41, the first transmission means 42 and the holding portion 46 to the frame body 8 via the attachment frame 47, the motor 41, the first transmission means 42 and the holding portion 46 can be assembled as a unit. , Productivity can be improved.

  Further, by attaching the motor 41 to the frame body 8 side, the optical axis O of the lens barrel 7 is shifted by the load of the motor 41 as compared with the case where the motor is attached to the lens barrel side, or zooming by the zoom ring 16 is performed. It is possible to prevent the operability of the function from being lowered.

  Then, the holding portion 46 can be stably supported by pivotally supporting the holding portion 46 at two locations of the rotating plates 65 and 65.

  Further, by using the worm gear WG, the rotation state of the first transmission means 42 is maintained without the worm gear WG rotating reversely due to the weight of the first transmission means 42, etc., so that the throttle device 31 operates unexpectedly. Therefore, it is possible to prevent the contrast from changing.

  In the above embodiment, the diaphragm plate of the diaphragm device 31 is not limited to two, and three or more diaphragm plates may be provided.

  Further, a configuration is also possible in which each of the diaphragm plates 31a and 31b can be driven independently, and the amount of entry into the optical path can be adjusted for each diaphragm plate.

  Furthermore, each transmission means 42 and 43 can also be configured as a roller in place of the rotating gear.

  Then, instead of setting the length of the gear groove of the gear portion 75 of the second transmission means 43 to be longer than the moving distance of the movable lens barrel 18, the gear grooves of the transmission gears G1, G3 of the first transmission means 42 are set. The length may be set to be longer than the moving distance of the movable lens barrel 18 or the gear grooves of both the gear portion 75 of the second transmission means 43 and the transmission gears G1 and G3 of the first transmission means 42 may be used. May be set longer than the moving distance of the movable lens barrel 18.

  Further, the projector device 1 is not limited to the above configuration, and may be a transmissive projector device or a projector device that does not perform light modulation, for example.

It is a perspective view which shows a part of projection lens apparatus of one embodiment of this invention. It is a perspective view which shows a projection lens apparatus same as the above. It is a disassembled perspective view which shows a projection lens apparatus same as the above. It is a perspective view which shows the holding | maintenance part of a projection lens apparatus same as the above. (a) is a longitudinal sectional view showing a wide-angle state of the projection lens device, and (b) is a longitudinal sectional view showing a telephoto state of the projection lens device. It is a front view which shows the aperture means of the projection lens apparatus same as the above. (a) is a perspective view showing a closed state of the diaphragm means of the projection lens device, and (b) is a perspective view showing an opened state of the diaphragm means. It is a top view which shows the projector apparatus provided with the projection lens apparatus same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Projector apparatus 2 Lamp as light source 6 DMD as light modulation means
7 Lens barrel as projection optical system
18 moving lens barrel
31 Aperture device
31a, 31b Diaphragm plate as diaphragm
32 Aperture drive means
33 Projection lens device O Optical axis

Claims (4)

A projection lens device for a projector device that projects light,
A projection optical system including a movable lens barrel that is movable along the optical axis direction and performs a zoom operation by this movement ;
A diaphragm device comprising a plurality of diaphragms along the optical axis direction, capable of blocking stray light and adjusting the amount of light passing through the projection optical system,
A diaphragm driving means for changing the amount of light regulated by the diaphragm device,
The diaphragm device is movable in the optical axis direction integrally with the movable lens barrel, and the projection light passing through one diaphragm body located on the front side in the optical axis direction is more optically axial than the diaphragm body. A projection lens device, characterized in that other apertures located on the rear side are arranged so as not to block light. The projection lens device according to claim 1, wherein the stop body is formed in an arc shape protruding toward the optical axis side. A light source;
Light modulating means for modulating light from the light source;
A projector device comprising: the projection lens device according to claim 1, wherein the light modulated by the light modulation means is projected onto a screen. The light modulation means is a reflective element that reflects light from the light source to the projection lens device when turned on, and reflects light in a direction different from that when turned on when turned off,
The projector device according to claim 3, wherein the diaphragm device is disposed on a side where light is reflected when the light beam is turned off with respect to the optical axis.

Images