JP2006106581A - Lens-driving apparatus and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens-driving apparatus and a projector capable of satisfactorily adjusting the position of a lens in the optical axis direction, by controlling the forward drive/backward drive and continuous driving time of a drive motor, and capable of simplifying the constitution and reducing the manufacturing cost. <P>SOLUTION: The apparatus includes a projection lens 11a which has a gear part 16 on the outer circumferential part, which is shifted in the optical axis direction according to the rotational state of the gear part 16; the drive motor 18 for rotationally driving the gear part 16; an operation part 6 for adjusting the position of the projection lens 11a in the optical axis direction; and a CPU 8 for detecting the input state by the operation part 6 and the continuous time of the input state, and then, separately performing the drive control, with reference to the rotating direction of the driving motor 18 and the continuous driving time of the motor 18 according to the detection results. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a lens driving device and a projector for performing focus adjustment of an image projected on a projection surface such as a screen by driving a lens.

  Conventional projectors generally disclose a projector that adjusts lens focus adjustment, which is required when an image is projected on a projection surface such as a screen, by driving a lens with a drive motor (for example, Patent Documents). 1). Conventional projectors include a focus adjustment mechanism for performing manual focus adjustment in addition to autofocus adjustment that automatically performs focus adjustment.

When performing manual focus adjustment, it is necessary to perform rough adjustment to move the lens of the projection optical system relatively large and fine adjustment to move the lens by a small amount in consideration of operability during adjustment. become. For this reason, the focus adjustment mechanism is configured to include a rotation speed control mechanism that controls the rotation speed of the drive motor in order to perform coarse adjustment and fine adjustment by controlling the movement amount of the lens.
JP 11-109214 A

  As described above, the conventional projector needs to include a complicated control mechanism for controlling the rotational speed of the drive motor in order to perform coarse adjustment and fine adjustment, respectively. Therefore, the method for controlling the rotational speed of the drive motor has the disadvantage that the focus adjustment mechanism is provided with the rotational speed control mechanism, which complicates the configuration and increases the manufacturing cost.

  Therefore, the present invention makes it possible to satisfactorily adjust the position of the lens in the optical axis direction by controlling the forward drive / reverse drive and the continuous drive time of the drive motor, simplify the configuration, and reduce the manufacturing cost. It is an object of the present invention to provide a lens driving device and a projector capable of achieving the above.

  In order to achieve the above-described object, a lens driving device according to the present invention is provided with a gear portion on an outer peripheral portion, and a lens that is moved in the optical axis direction according to the rotation state of the gear portion, and the gear portion is rotationally driven. A drive motor, operation means for adjusting the position of the lens in the optical axis direction, an input state by the operation means and a duration of the input state are detected, and the rotation direction and continuous drive time of the drive motor are detected according to the detection result. And a control means for controlling the drive of each.

  According to the lens driving device according to the present invention configured as described above, when the lens is moved in the optical axis direction by the operating unit, the driving motor is adjusted according to the input state by the operating unit and the duration of the input state. By controlling the rotation direction and continuous drive time of the rotation drive and the inversion drive, it is possible to satisfactorily adjust the position of the lens in the optical axis direction. Therefore, according to this lens driving device, the configuration for coarse and fine adjustment of the lens can be simplified.

  A projector according to the present invention includes the above-described lens driving device according to the present invention and a projection optical system for projecting an image on a projection surface via the lens. And a lens drive device adjusts the focus of a projection image with respect to a projection surface by moving a lens.

  As described above, according to the present invention, the configuration can be simplified and the manufacturing cost can be reduced.

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

  As shown in FIG. 1, the projector 1 adjusts the focus of a projection image 3 projected on the projection surface and a projection unit 3 having a projection optical system 11 for projecting an image on a projection surface such as a screen. A lens driving unit 5 that is a lens driving unit that drives the projection lens 11a of the projection optical system 11, an operation unit 6 that is an operating unit for manually operating the lens driving unit 5, and the projection unit 3 and the lens driving unit. A CPU (Central Processing Unit) 8 that is a control means for controlling the unit 5 and the like, and a housing 9 that covers the projection unit 3, the lens driving unit 5, and the like are provided.

  Although not shown, the projector 1 includes a distortion correction circuit unit that corrects distortion of the projected video on the projection surface, and an optical zoom unit that enlarges and reduces the projected video.

  The projection unit 3 includes a projection optical system 11 for projecting a video on a projection surface, a video display unit 12 that displays a video to be projected, and a video control unit 13 that controls a video displayed on the video display unit 12. have. The projection optical system 11 has a projection lens 11a which is also a focus lens, and is provided so as to be rotatable around the projection optical axis. As the video display unit 12, for example, a light transmission type liquid crystal display plate or a reflection type liquid crystal display plate is used. Instead of the image display unit 12, a DMD (digital micromirror device) that reflects incident light from a light source as an image may be used.

  As shown in FIGS. 1 and 2, the lens driving unit 5 includes an annular gear unit 16 provided on the outer periphery of the projection lens 11 a, a pinion 17 meshed with the gear unit 16, and the pinion 17. And a drive motor 18 for rotational driving. The lens driving unit 5 rotates the gear unit 16 in the directions of arrows a and b in FIG. 2 around the projection optical axis via the pinion 17 by driving the driving motor 18 forward and backward. Accordingly, the projection lens 11a is moved along the direction of the projection optical axis as the gear unit 16 is rotated, and the focus position of the projection image by the projection optical system 11 is adjusted.

  Although not shown, the projector 1 has an autofocus circuit unit for automatically adjusting the focus position by the projection optical system 11, and when the operation is not performed by the operation unit 6, the autofocus is performed. Focus adjustment is performed by the circuit unit.

  The operation unit 6 includes a forward rotation operation button 21 and a reverse rotation operation button 22 that are pressed, and a conversion element 23 that converts the electric signal according to the operation state of the forward rotation operation button 21 and the reverse rotation operation button 22. is doing.

  When the forward rotation operation button 21 is pressed, the CPU 8 drives and controls the drive motor 18 of the lens driving unit 5 in the forward rotation direction through the conversion element 23 to move the projection lens 11a to one end side. Similarly, when the reverse operation button 22 is pressed, the CPU 8 drives and controls the drive motor 18 in the reverse direction via the conversion element 23 to move the projection lens 11a to the other end side. As the conversion element 23, for example, a piezoelectric element is used, and an input signal corresponding to the operation status of each operation button 21, 22 is output to the CPU 8.

  Based on the output signal from each conversion element 23, the CPU 8 detects the presence / absence of an input state in which each forward rotation operation button 21 and reverse rotation operation button 22 are pressed, and the type of the pressed operation buttons 21 and 22. In addition, the duration of the input state of each operation button 21, 22 is detected.

  Then, the CPU 8 drives the driving motor 18 of the lens driving unit 5 in the normal rotation driving and the reverse driving in accordance with the input state of the operation buttons 21 and 22 and the duration of the input time, and driving in two types of continuous driving time. And stop control respectively.

  In other words, the CPU 8 is a relatively short input state in which the input state in which the operation buttons 21 and 22 are pressed down continues for a certain period of time, for example, 0.25 seconds or longer, which is “long press operation”, which is less than 0.25 seconds. The input state is detected as “short press operation”, and a control signal is generated. When the operation buttons 21 and 22 are “long press operations”, the CPU 8 relatively increases the continuous drive time of the drive motor 18, thereby increasing the amount of movement of the projection lens 11 a and roughly adjusting the focus. . In addition, when the operation buttons 21 and 22 are “short press operations”, the CPU 8 reduces the moving amount of the projection lens 11 a by relatively shortening the continuous drive time of the drive motor 18, and finely adjusts the focus. Is done.

  Further, as shown in FIG. 2, the projector 1 includes a light emitting unit 28 that emits an input signal corresponding to an operation state by infrared rays in order to perform the same operation content as the operation by the operation unit 6 described above. 27 and a light receiving portion 29 for receiving infrared rays from the light emitting portion 28 of the remote control device 27.

  The remote control device 27 includes a forward operation button 31 and a reverse operation button 32 that are pressed down, an input state by the forward operation button 31 and the reverse operation button 32, and an input signal corresponding to the duration of the input state. And a light emitting unit 28 that converts an input signal corresponding to the operation state of the forward operation button 31 and the reverse operation button 32 into infrared rays and emits it. Yes. The light receiving unit 29 is provided on the outer periphery of the housing 9, and outputs a control signal to the CPU 8 based on infrared rays from the remote control device 27.

  Therefore, in the projector 1, the lens drive unit 5 can be similarly driven and controlled by the remote control device 27 instead of the operation by the operation unit 6.

  With respect to the projector 1 configured as described above, an operation of performing coarse adjustment and fine adjustment of the focus of the projection lens 11a according to the operation state of the operation unit 6 will be described.

  First, a case where the focus is finely adjusted by performing a “short press operation” on the operation buttons 21 and 22 will be described with reference to FIG. 3A to 3C, the L level indicates a state where the operation buttons 21 and 22 are pressed, and the H level indicates a state where the operation buttons 21 and 22 are not pressed.

  3A, 3B, and 3C show input signals detected by the CPU 8. FIG. FIG. 3A shows an input signal corresponding to the “short press operation” of the forward rotation operation button 21. FIG. 3B shows an input signal corresponding to the “short press operation” of the reverse operation button 22. As a result, the CPU 8 detects the type of the operation buttons 21 and 22 that have been “short-pressed”.

  FIG. 3C shows an input signal corresponding to the “long press operation” of the operation buttons 21 and 22. In FIG. 3, the L level indicates a state where the operation buttons 21 and 22 are “long-pressed”, and the H level indicates a state where the operation buttons 21 and 22 are not “long-pressed”.

  The CPU 8 detects the operation state of the operation buttons 21 and 22 based on the input signals shown in FIGS. 3A, 3B and 3C, and then drives as shown in FIGS. 3D and 3E. Control signals for driving and controlling the motor 18 are generated and output to the drive motor 18. FIG. 3D shows a control signal for controlling the drive of the drive motor 18 for a relatively short time. As shown in FIG. 3D, the drive motor 18 is rotationally driven at the L level, and the drive of the drive motor 18 is stopped at the H level. FIG. 3E shows a control signal for controlling the rotation direction of the drive motor 18. At the H level, the rotation direction of the drive motor 18 is set to the normal rotation direction, and at the L level, the rotation direction of the drive motor 18 is set to the reverse direction.

  When fine adjustment is performed by the operation buttons 21 and 22, as shown in FIGS. 3A, 3B, and 3D, the CPU 8 does not wait for the input state to be released by the operation buttons 21 and 22 and does not wait for input. When the duration of the state exceeds a predetermined time, the drive of the drive motor 18 is automatically stopped.

  In the projector 1, particularly when operated by the remote control device 27, a delay time required for transmission and reception of input signals by the light emitting unit 28 and the light receiving unit 29 occurs. However, the continuation of the input signal at the L level shown in FIGS. 3A and 3B due to the configuration in which the delay time is generated by automatically stopping the driving motor 18 as described above. Even when the time is longer than necessary, fine adjustment of the focus can be performed satisfactorily.

  Next, a case where rough adjustment is performed by performing “long pressing operation” of the operation button will be described with reference to FIG. 4A to 4E show the same signals as the input signals and control signals shown in FIGS. 3A to 3E, respectively.

  When the operation buttons 21 and 22 are “long-pressed”, as shown in FIG. 4D, the CPU 8 once drives in the same manner as the control when the operation buttons 21 and 22 are “short-pressed”. After driving the motor 18, when it is detected that the “long press operation” is detected, the drive motor 18 is driven again and the input state is canceled by the operation buttons 21 and 22, and the input state is released. Sometimes the drive motor 18 is stopped.

  As described above, the CPU 8 drives and controls the rotation direction and the continuous drive time of the forward drive / reverse drive by the drive motor 18 according to the input state of the operation buttons 21 and 22 and the duration of the input state. Thus, the coarse adjustment and fine adjustment of the focus of the projection lens 11a can each be performed satisfactorily.

  Further, the drive control of the lens drive unit 5 by the operation of the remote control device 27 is the same as the drive control by the operation unit 6 described above, and thus the description thereof is omitted.

  As described above, according to the projector 1, the coarse adjustment and fine adjustment of the focus can be satisfactorily performed according to the input state by the operation unit 6 or the remote control device 27 and the duration of the input state. There is no need to provide a conventional rotational speed control mechanism for controlling the rotational speed of the drive motor, and the configuration of the lens driving unit 5 can be simplified, and the manufacturing cost can be reduced.

  In the projector 1 according to the above-described embodiment, the operation unit 6 is configured to include the operation buttons 21 and 22 to be pressed. However, for example, the operation unit 6 includes other operation members that are operated to slide or swing. May be. In the case of this configuration, the rotation direction of the drive motor is driven and controlled in the direction in which the operation member slides or swings.

  In the above-described embodiment, the projection lens 11a is configured to be moved by the operation unit 6, but the other lens of the projection optical system or the zoom lens of the optical zoom unit is configured to be moved. Also good.

It is a schematic diagram which shows the projector which concerns on this invention. It is a schematic diagram which shows an operation part and a lens drive part. It is a figure for demonstrating the input signal and control signal at the time of carrying out fine adjustment of a focus. It is a figure for demonstrating the input signal and control signal at the time of carrying out rough adjustment of a focus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Projector 3 Projection part 5 Lens drive part 6 Operation part 8 CPU
DESCRIPTION OF SYMBOLS 11 Projection optical system 11a Projection lens 16 Gear part 18 Drive motor 21 Forward rotation operation button 22 Reverse rotation operation button 27 Remote control apparatus

Claims (6)

A lens provided with a gear part on the outer peripheral part and moved in the optical axis direction according to the rotation state of the gear part;
A drive motor for rotationally driving the gear portion;
Operating means for adjusting the position of the lens in the optical axis direction;
Control means for detecting the input state by the operation means and the duration of the input state, and driving and controlling the rotation direction and continuous drive time of the drive motor according to the detection result;
A lens driving device.   2. The control unit according to claim 1, wherein the control unit drives and controls the drive motor to a first continuous drive time and a second continuous drive time shorter than the first continuous drive time according to the duration time. Lens drive device.   The control means controls the drive motor before the input state by the operation means is released when the drive time of the drive motor is controlled to be the second continuous drive time and the duration time exceeds a predetermined time. The lens driving device according to claim 1, wherein the driving of the lens is automatically stopped.   The control means, when controlling the drive of the drive motor for the first continuous drive time, once controls the drive for the second continuous drive time, and then controls the drive for the first continuous drive time. The lens driving device according to 2 or 3. The operation means having a light emitting unit that emits an input signal according to the input state and the duration time by infrared rays;
A light receiving unit that receives the infrared light from the light emitting unit and outputs the input signal to a pre-control unit;
The lens driving device according to claim 1, comprising: The lens driving device according to any one of claims 1 to 5,
A projection optical system for projecting an image on a projection surface via the lens;
The lens driving device is a projector that adjusts a focus of a projected image with respect to the projection surface by moving the lens.

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