JP2005070296A - Photographing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate focusing without employing an autofocusing system, in a photographing apparatus in which a camera section is attached to an arm member and focusing takes place by the movement of a focusing lens. <P>SOLUTION: The camera section 18 of a video projector 10 with a text-image camera is connected to the upper end of the arm 16 via a joint 32 and a click mechanism 34 so as to be freely turnable. With the click mechanism 34, the camera section can be turned to the position where it faces down or to the position where it faces a side. When the camera section 18 is set downwards, a first drive signal is read from the RAM 42 of a CPU 38 and it is outputted to a lens drive device 40. Consequently, the focusing lens 44 is put in a focused position when the camera section 18 is in the position where it faces down. When the camera section 18 is set in the position where it faces the side, a second drive signal is read from the RAM 42 and it is output to the lens drive device 40. Consequently, the focusing lens 44 is put in a focused position when the camera section 18 is in the position where it faces the side. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a photographing apparatus, and more particularly to a photographing apparatus such as a video projector with a document camera for photographing a document such as a document and projecting it on a screen.

  In recent years, video projectors with document cameras have become widespread instead of overhead projectors as projectors used for presentations (Patent Document 1).

  In a video projector with a document camera, a camera unit is attached to an arm of a projector main body, a document is placed on a table of the projector main body, and the document is photographed by the camera unit, thereby projecting a document image on a screen.

By the way, the camera unit is used not only for photographing a document placed on a table but also for photographing the scenery of a presentation venue, for example, by changing the orientation from the position. In such a case, if the orientation of the camera unit is changed with the camera unit attached to the arm, and the focus ring of the lens device is manually rotated to focus, the arm shakes and the screen shakes. So it ’s hard to focus. This problem can be solved by using an autofocus lens device, but since an autofocus lens device is expensive, a panfocus lens device is generally used.
JP 11-252454 A

  However, since the focus distance of a pan-focus lens device is limited, it is difficult to focus at a wide range from close to far. For example, a document camera lens device that emphasizes close-up shooting is far away. When shooting a subject, it is difficult to cope with pan focus. As a result, if it is desired to take a good image far away, it can only be handled by a lens device that moves the focus lens. However, in manual operation, focusing is difficult as described above, and autofocus is expensive. There was a problem.

  The present invention has been made in view of such circumstances, and is an imaging device in which a camera unit is attached to an arm member and a focus lens moves to focus, and the focus can be easily achieved without adopting an autofocus method. It is an object of the present invention to provide a photographing apparatus that can be matched.

  In order to achieve the above object, the present invention provides a camera unit having a lens device rotatably attached to an arm member provided in a photographing apparatus main body, and the camera unit has a rotational position with respect to the arm member. Position detecting means for detecting, and lens driving means for moving the focus lens of the lens device to a focusing position corresponding to the rotational position based on the rotational position of the camera unit detected by the position detecting means. It is characterized by having.

  In order to achieve the above object, according to the present invention, a camera unit including a lens device is attached to an arm member that is rotatably provided on the photographing apparatus main body, and the arm member is rotated relative to the photographing apparatus main body. Based on the position of the arm member detected by the position detection means, the position detection means for detecting the movement position, and the lens drive for moving the focus lens of the lens device to the in-focus position corresponding to the rotation position Means.

  Furthermore, according to the present invention, there is provided a video projector comprising the photographing apparatus according to claim 1 or 2 and comprising a projection lens for projecting an image photographed by the photographing apparatus.

  According to the present invention, when the shooting direction is changed by rotating the camera unit with respect to the arm member, the position detection unit detects the rotation position of the camera unit with respect to the arm member, and the lens is based on the rotation position. The driving means moves the focus lens of the lens device to a focusing position corresponding to the rotation position. This automatically adjusts the focus.

  Further, according to the present invention, when the shooting direction is changed by rotating the arm member with respect to the photographing apparatus main body, the position detecting means detects the rotational position of the arm member with respect to the photographing apparatus main body, and this rotational position. Based on the above, the lens driving means moves the focus lens of the lens device to a focus position corresponding to the rotation position. This automatically adjusts the focus.

  According to the photographing apparatus of the present invention, when the direction of photographing is changed by rotating the camera unit with respect to the arm member, the position detecting unit detects the rotational position of the camera unit with respect to the arm member, and this rotational position. Based on the above, the lens driving means moves the focus lens of the lens device to a focus position corresponding to the rotation position. As a result, since the focus is automatically adjusted, it is possible to provide an imaging device that is easy to focus.

  Further, according to the photographing apparatus according to the present invention, when the direction of photographing is changed by rotating the arm member relative to the photographing apparatus main body, the position detecting unit detects the rotational position of the arm member with respect to the photographing apparatus main body, Based on this rotation position, the lens driving means moves the focus lens of the lens device to a focusing position corresponding to the rotation position. As a result, since the focus is automatically adjusted, it is possible to provide an imaging device that is easy to focus.

  Hereinafter, preferred embodiments of a photographing apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a perspective view of a video projector (shooting apparatus) 10 with a document camera according to a first embodiment. The video projector 10 has a projector main body (shooting apparatus main body) 14 having a projection lens 12 attached to a side surface, and a camera unit 18 is attached to an upper end portion of an arm 16 erected on the projector main body 14. . The camera unit 18 captures a document 22 placed on the table 20 of the projector main body 14, takes a position facing downward, and photographs a scene of the presentation venue as shown in FIG. 2, for example. It is connected to the arm 16 so as to be rotatable between positions. The image signal of the document 22 photographed by the camera unit 10 or the image signal of the scenery of the presentation venue is converted into a video signal by a video signal processing device (not shown) built in the projector main body 14, and this is converted into a transmissive liquid crystal display. By displaying on the substrate and irradiating the transmissive liquid crystal display substrate with a light source, an original image or a landscape image is projected from the projection lens 12 onto a screen (not shown). In the projector body 14, fluorescent lamps 24 and 24 for illuminating the document 22 placed on the table 20 are attached to the projector body 14 via poles 26.

  The camera unit 18 includes a camera body 28 having a built-in solid-state image sensor (not shown) and a lens device 30, and is rotated to the upper end of the arm 16 via a joint 32 and a click mechanism 34 as shown in FIG. It is connected freely. The camera unit 18 is rotated about the rotation axis A of the joint 32 (the axis indicated by the alternate long and short dash line in FIG. 3: a horizontal axis) by the joint 32, and the downward direction position of FIG. The rotational position is positioned at the lateral direction.

  The camera unit 18 incorporates a potentiometer 36, which is a position detection device (position detection means), a CPU 38, and a lens drive device (lens drive means) 40 such as a motor and a solenoid. The potentiometer 36 has a sliding contact attached to the rotating portion of the joint 32, and when the camera unit 18 is in the downward direction of FIG. In addition to the output, a signal indicating the second resistance value is output to the lens driving device 40 when the camera unit 18 is in the lateral direction of FIG. Note that the first resistance value and the second resistance value from the potentiometer 36 may be output to the CPU 38.

  When the first resistance value is output from the potentiometer 36 to the lens driving device 40, the focus lens 44 is moved along the photographing optical axis P by the lens driving device 40, and the camera unit 18 is in the downward position in FIG. The focus lens 44 is located at the in-focus position. Further, when the second resistance value is output from the potentiometer 36 to the lens driving device 40, the lens driving device 40 moves the focus lens 44 along the photographing optical axis P, and the camera unit 18 moves sideways in FIG. The focus lens 44 is located at the in-focus position at the position.

  On the other hand, the camera unit 18 in which the first resistance value and the second resistance value from the potentiometer 36 are output to the CPU 38 will be described. In the RAM 42 of the CPU 38, when the camera unit 18 is at the downward position in FIG. A first drive signal for positioning the focus lens 44 of the lens device 30 in the focal position is stored, and the focus lens of the lens device 30 is in the in-focus position when the camera unit 18 is in the lateral position in FIG. A second drive signal for positioning 44 is stored. When the potentiometer 36 outputs a signal indicating the first resistance value, the CPU 38 reads the first drive signal from the RAM 42 and outputs it to the lens driving device 40. Accordingly, the focus lens 44 is moved along the photographing optical axis P by the lens driving device 40, and the focus lens 44 is positioned at the in-focus position when the camera unit 18 is in the downward position in FIG. Further, when a signal indicating the second resistance value is output from the potentiometer 36, the CPU 38 reads out the second drive signal from the RAM 42 and outputs it to the lens driving device 40. As a result, the focus lens 44 is moved along the photographing optical axis P by the lens driving device 40, and the focus lens 44 is positioned at the in-focus position when the camera unit 18 is in the lateral position in FIG.

  The lens driving device 40 includes a fixed cylinder in which a rectilinear groove is formed and a cam cylinder in which a cam groove is formed, and the cam pin of the focus lens holding frame is engaged with the rectilinear groove and the cam groove to rotate the cam cylinder. In the case of a mechanism for moving the focus lens holding frame by a motor, a motor for rotating the cam cylinder can be exemplified. In the case of a mechanism for moving the focus lens 44 along the optical axis P, a solenoid and an iron core are used. A linear motion device can be exemplified. In other words, the focus lens 44 is moved through the iron core by attaching the iron core to the focus lens holding frame and controlling the voltage applied to the solenoid.

  As described above, according to the video projector with a document camera 10 according to the first embodiment, the camera unit 18 can be focused simply by changing the direction of the camera unit 18 with respect to the arm 16.

  4 and 5 are perspective views of the video projector 50 with a document camera according to the second embodiment, and are the same as the video projector 10 with a document camera according to the first embodiment shown in FIGS. Alternatively, similar members will be described with the same reference numerals.

  The arm 52 of the video projector 50 shown in FIGS. 4 and 5 is configured to be rotatable by a hinge portion 54. That is, the arm 52 includes a main body arm 56 fixed to the table 20 of the projector main body 14, and a rotating arm 58 connected to the main body arm 56 via a hinge portion 54. The camera unit 18 is connected to the camera. As shown in FIG. 6, the hinge portion 54 is provided with a click mechanism 60. With this click mechanism 60, a position rotated 90 ° (see FIG. 4) at which the document 22 is imaged by the camera portion 18 and the scenery of the presentation venue. The rotating arm 58 is positioned between the position (see FIG. 5) extending in a straight bar shape for photographing the image.

  Further, a potentiometer 64 which is a position detection device (position detection means) is attached to the hinge portion 54 as shown in FIG. The potentiometer 64 has a sliding contact attached to the rotating portion of the hinge portion 54. When the rotating arm 58 rotates 90 ° with respect to the main body arm 56 (see FIG. 4), the first resistance value is obtained. A signal indicating the second resistance value is output to the lens driving device 40 when the rotating arm 58 extends with respect to the main body arm 56 (see FIG. 5). The

  When the first resistance value is output from the potentiometer 64 to the lens driving device 40, the focus lens 44 is moved along the photographing optical axis P by the lens driving device 40, and the camera unit 18 is in the downward position in FIG. 4. The focus lens 44 is located at the in-focus position. Further, when the second resistance value is output from the potentiometer 64 to the lens driving device 40, the lens driving device 40 moves the focus lens 44 along the photographing optical axis P, and the camera unit 18 moves sideways in FIG. The focus lens 44 is located at the in-focus position at the position.

  As described above, according to the video projector with a document camera 50 according to the second embodiment, since the focus is automatically adjusted only by changing the position of the rotation arm 58, the focus can be easily adjusted.

  In place of the potentiometer 64, the rotation amount of the gear mechanism 70 shown in FIG. 7 is detected and transmitted to the lens driving device 40 (see FIG. 6), whereby the rotation arm 58 is moved to the position shown in FIG. Position detecting means for transmitting to the lens driving device 40 side that it is located at position 5 can be applied. The gear mechanism 70 is fixed to the upper end portion of the main body arm 56, meshed with the gear 72, and rotatably attached to the rotating arm 58. A gear 74 that revolves around and rotates, and a rotation amount detection means (not shown) that detects the rotation amount of the gear 74 and outputs this information to the lens driving device 40 of FIG.

  The lens driving device 40 moves the focus lens 44 based on the rotation amount output from the rotation amount detection means, and adjusts the focus position of the focus lens 44.

  Moreover, the switch mechanism 80 shown in FIG. 8 can also be applied. The switch mechanism 80 includes a pressing piece 82 fixed to the main body arm 56 and a switch 86 having a contact piece 84 fixed to the rotating arm 58. According to the switch mechanism 80, when the rotation arm 58 is rotated 90 ° as shown in FIG. 8, the switch 86 is turned OFF, and this signal is output to the lens driving device 40 of FIG. When the rotating arm 58 is extended, the contact piece 84 is pushed by the pressing piece 82 and the switch 86 is turned on, and this signal is output to the lens driving device 40 of FIG.

  The lens driving device 40 moves the focus lens 44 based on the ON / OFF signal output from the switch 86 and adjusts the focus position of the focus lens 44.

  FIG. 9 shows a camera main body 28 of the camera unit 18 shown in FIG. 4 that is rotatably connected to the tip of a rotary arm 58. The connecting part has its rotational position as shown in FIG. A potentiometer 36 is provided for detecting. As a result, when the camera body 28 is rotated and the camera unit 18 is directed to the side as shown in FIG. 9, the focus lens 44 of the lens device 30 is positioned at the in-focus position for photographing the scenery of the presentation venue.

The perspective view which shows the state which the video projector with a document camera of 1st Embodiment image | photographs a document The perspective view which shows the state which the video projector with a document camera of 1st Embodiment image | photographs scenery Structure diagram of camera part of document camera shown in FIG. The perspective view which shows the state which the video projector with a document camera of 2nd Embodiment image | photographs an original document The perspective view which shows the state which the video projector with a document camera of 2nd Embodiment image | photographs the scenery Structure diagram of camera part and arm of document camera shown in FIG. Main part structure diagram showing an example of position detecting means by gear mechanism Main part structure diagram showing an example of position detecting means by switch The perspective view which shows the example in which the camera part of the document camera was provided rotatably at the front-end | tip of a rotation arm

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10, 50 ... Video projector with a document camera, 12 ... Projection lens, 14 ... Projector body, 16, 52 ... Arm, 18 ... Camera part, 20 ... Table, 22 ... Document, 24 ... Fluorescent lamp, 28 ... Camera body, 30 ... Lens device, 32 ... Joint, 34, 60 ... Click mechanism, 36, 64 ... Potentiometer, 38 ... CPU, 40 ... Lens drive device, 42 ... RAM, 44 ... Focus lens, 54 ... Hinge part, 56 ... Body arm, 58 ... Rotating arm, 70 ... Gear mechanism, 80 ... Switch mechanism

Claims (3)

  A camera unit equipped with a lens device is rotatably attached to an arm member provided in the photographing apparatus main body, and a position detection unit that detects a rotation position of the camera unit with respect to the arm member, and the position detection unit An imaging device comprising: lens driving means for moving a focus lens of the lens device to a focus position corresponding to the detected rotation position of the camera unit based on the detected rotation position.   A position detection means for detecting a rotation position of the arm member with respect to the imaging apparatus body, wherein a camera unit having a lens device is attached to an arm member rotatably provided in the imaging apparatus body, and the position detection means An imaging device comprising: lens driving means for moving the focus lens of the lens device to a focus position corresponding to the rotation position of the arm member based on the rotation position of the arm member detected in step (1).   A video projector comprising the photographing apparatus according to claim 1, further comprising a projection lens that projects an image photographed by the photographing apparatus.

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