JP2014075640A - Area photographing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify image correction, and to enable photographing from a distance close to a plate surface.SOLUTION: A rail 5 extending in a lateral direction of a plate surface 1a is provided on an upper edge part of a frame body 4 of a white board 1. A slider 6 is provided on the rail freely movably. A first arm 11 extending upward is supported by the slider. A second arm extending toward a front side of the plate surface is supported by the first arm. A camera 3 is supported by an extending end part of the second arm. An imaging element and a lens, and a free-curved surface mirror for bending incoming light from the plate surface toward the imaging element via the lens are provided in the camera. A mechanism for changing a direction of the camera, which adjusts a relative angle between respective members of the slider, the first arm, the second arm, and the camera, is provided. Distortion in an image can be reduced by the free-curved surface mirror to enable photographing from a distance close to the plate surface, and even when deviation to the plate surface of a photographing region occurs, the deviation can be corrected by changing the direction of the camera.

Description

  The present invention relates to an area photographing apparatus capable of photographing a plate surface such as a white board.

  For example, there is a demand to shoot what is written on or projected on paper, electronic blackboards, whiteboards, etc. with a digital camera, and process the image data with a personal computer etc. and display it on a monitor . In such a conventional photographing apparatus, for example, in the case of an electronic blackboard, an arm extending from the upper frame of the plate surface to the front side of the plate surface is provided, and the plate surface is photographed obliquely from above with a camera fixed to the tip of the arm. (For example, refer to Patent Document 1)

CN202231786U

  By installing the camera above the plate surface as described above, it is possible to photograph the plate surface with the camera without disturbing a writer or the like standing in front of the plate surface. However, when the camera is close to the plate surface, the captured image is greatly distorted. For example, image correction by computer processing is possible. In that case, however, enormous processing steps are required, and control is required for high-speed processing. There arises a problem that the apparatus becomes expensive.

  By taking the camera away from the plate surface as in Patent Document 1, distortion of the captured image can be reduced. For this reason, if the extension length of the arm from the plate surface is increased, the distal end of the arm becomes obstructive. Become annoying or annoying. Therefore, in the above-mentioned Patent Document 1, two positions can be selected: a state in which the arm extends in the front direction of the plate surface serving as the photographing position and a state in which the arm is placed along the upper frame of the plate surface serving as the storage position. I am doing so. However, the arm is unlikely to get in the way when not in use, but the arm extends greatly from the plate surface when in use, so it is difficult to use in situations where the plate surface is viewed from diagonally above, such as a staircase classroom. May occur.

  On the other hand, for example, when a model or the like is placed on the upper surface of a desk arranged on the front side of the electronic blackboard, the versatility of the imaging device can be improved by enabling the model or the like to be photographed. However, in Patent Document 1, since the camera is fixed to the tip of the arm and only the plate surface is taken, it is not possible to shoot an area other than the plate surface. There is no idea of making it a subject of photography.

  The present invention has been devised to solve such problems of the prior art, and the main purpose of the present invention is to make it possible to make the camera compact without taking it away from the plate surface. An object of the present invention is to provide an area photographing apparatus capable of simplifying image correction.

  The area photographing apparatus of the present invention is an area photographing apparatus in which the camera is supported by an arm attached to a member integral with the plate surface and extending toward the front side of the plate surface so as to photograph the plate surface by the camera. The camera includes an imaging device, a free-form curved mirror for reflecting incident light toward the imaging device, and a lens for condensing the reflected light reflected by the free-form curved mirror on the imaging device. And the arm has a mechanism for changing the orientation of the camera so as to correct a deviation in a direction along the plate surface from a reference position where a photographing region of the camera is aligned with the entire plate surface. .

  According to the present invention, a camera that collects reflected light reflected by a free-form surface mirror onto an image pickup device by a lens is used, and the camera is supported by an arm that extends toward the front side of the plate surface to photograph the plate surface. Therefore, the image distortion can be reduced by the free-form surface mirror without using image correction processing by a program, and photographing from a distance close to the plate surface becomes possible. Even if the shooting area shifts from the plate surface by supporting the camera with the arm, the camera position correction means can correct the shift by changing the direction of the camera, and an extra margin of the shooting area considering the shift. Therefore, the resolution of the image on the plate surface can be increased.

The perspective view which shows an example of the imaging device by this invention A perspective view showing the entire camera and arm Sectional cross-sectional view taken along the line III-III in FIG. 3 is an exploded perspective view of the main part of the part shown in FIG. The principal part disassembled perspective view showing the configuration of the first arm Assembly exploded perspective view showing how to attach the second arm and camera Side sectional view showing the main components of the camera Main part perspective view showing main components of the camera taken out The side view which shows the imaging | photography state of the board surface by the imaging device to which this invention was applied 4A and 4B are diagrams illustrating a shift of an imaging region with respect to a plate surface, where FIG. 5A is a diagram when the camera is tilted to the upper side of the plate surface, and FIG. 5B is a diagram when the camera is tilted to the lower side of the plate surface; ) Is the figure when the camera is facing the right side of the plate (A) is a figure which shows the change of the shift | offset | difference of the imaging | photography area | region by the difference in the angle of the tilt direction of a camera, (b) is a figure which shows the change of the shift | offset | difference of the imaging | photography area | region by the difference in the camera height direction. Side view showing an example of photographing a place different from the plate surface The figure corresponding to FIG. 1 which shows an example in the case of image | photographing by shifting a camera to the horizontal direction from the center position of a board surface. Overall perspective view showing an example of photographing the top surface of a desk

  According to a first aspect of the present invention, there is provided an arm attached to a member integral with the plate surface and extended toward the front side of the plate surface so as to photograph the plate surface with a camera. An area photographing apparatus supporting a camera, wherein the camera includes an imaging device, a free-form curved mirror for reflecting incident light toward the imaging device, and reflected light reflected by the free-form curved mirror. A lens for condensing the light, and the arm changes the direction of the camera in order to correct a shift in a direction along the plate surface from a reference position where an imaging region of the camera is aligned with the entire plate surface. A structure having a changing mechanism is adopted.

  According to this, using a camera that condenses the reflected light reflected by the free-form surface mirror onto the image sensor with a lens, the camera is supported by an arm that extends toward the front side of the plate surface and images the plate surface. Therefore, the image distortion can be reduced by the free-form surface mirror without using the image correction processing by the program, and photographing from a distance close to the plate surface becomes possible. Even if the shooting area shifts from the plate surface by supporting the camera with the arm, the camera position correction means can correct the shift by changing the direction of the camera, and an extra margin of the shooting area considering the shift. Therefore, the resolution of the image on the plate surface can be increased.

  In addition, a second invention includes a base member attached to a member integral with the plate surface in the first invention, and the arm extends outwardly along the plate surface. A first arm supported by a base member; a second arm supported by the first arm so as to extend toward the front side of the plate surface; and the second arm for fixing and supporting the camera. A mechanism for changing the orientation of the camera, between the base member and the first arm, and between the first arm and the second arm. The relative angle between the second arm and the camera fixing member is adjusted.

  According to this, the first arm and the second arm form, for example, an L-shaped arm shape as a whole, and the camera is supported by the extended end portion of the second arm serving as the extended end. The relative inclination angle between the base member and the first arm, the first arm and the second arm, and the second arm and the camera fixing member, which are coupling portions, can be adjusted. The tilt of the camera can be adjusted with high accuracy.

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

  FIG. 1 is a perspective view showing an example of a photographing apparatus according to the present invention. In the figure, a rectangular whiteboard 1 used in a state of standing on the floor is shown. The white board 1 is provided with a flat plate surface 1a, and characters, figures, etc. can be written on the plate surface 1a with a marker pen. An inverted L-shaped arm 2 that protrudes upward and extends from the protruding end to the front side (front side) of the plate surface 1a is attached to the upper edge surface of the whiteboard 1 as a member integral with the plate surface 1a. The camera 3 is supported by the extended end of the arm 2 in a suspended state. With the camera 3 provided in this manner, the entire plate surface 1a as a writing surface is photographed from above the whiteboard 1.

  The camera 3 has a built-in wireless device that enables wireless signal transmission / reception with, for example, a personal computer as a control device (not shown). Note that cable connection may be made so as to perform signal exchange by wire. By outputting the image signal processed by the personal computer to the monitor, it is possible to project characters, figures and the like written on the plate surface 1a on the monitor.

  FIG. 2 is a perspective view showing the entire camera 3 and arm 2. 1 shows a state in which the arm 2 is covered with a cover 2a, and FIG. 2 shows the skeleton of the arm 2 with the cover 2a removed.

  The whiteboard 1 is provided with a rectangular frame 4 that surrounds the plate surface 1a so as to support the plate-like member that forms the plate surface 1a. 5 is attached. The rail 5 is provided over the entire length of the upper edge portion of the frame body 4.

  3 is a fragmentary sectional view taken along the line III-III of FIG. 2, and FIG. 4 is an exploded perspective view of the principal part shown in FIG. With reference to FIGS. 3 and 4, the base end portion (attachment portion to the frame body 4) of the arm 2 will be described.

  As shown in the cross-sectional shape of FIG. 3, the rail 5 has a downward convexity having an upper concave portion 5a that is formed in a concave shape that opens upward, and a groove portion 5b that is recessed in the central portion that is the bottom surface of the upper concave portion 5a. It is formed in a mold shape. A slider 6 as a rectangular plate-like base member is received in the upper concave portion 5a so as to be movable in the longitudinal direction of the rail 5 (lateral direction of the horizontally long rectangular plate surface 1a).

  A disc-shaped roller 7 is attached to the center of the lower surface of the slider 6. A circumferential groove 7 a is provided on the outer peripheral surface of the roller 7 over the entire circumference. In the illustrated example, as shown in FIG. 4, a screw is formed on a support shaft 7 b that coaxially supports the roller 7, and the support shaft 7 b is fastened to a corresponding female screw portion (not shown) of the slider 6. A roller 7 is integrated with the slider 6. Further, the ball 8a of the embedded ball plunger 8 is provided at the center of the left and right side surfaces of the slider 6 in FIG.

  The left and right side walls in FIG. 3 that form the upper concave portion 5a of the rail 5 are provided with a plurality of engagement holes 5c that are linearly arranged at equal intervals in the longitudinal direction of the rail. The engagement hole 5c is formed in a size that allows a part of the ball 8a to enter. Further, in the cross-sectional shape of the rail 5, on the inner surfaces of the left and right side walls in FIG. 3 of the groove portion 5b, a protrusion that engages with the circumferential groove 7a of the roller 7 in a state where the slider 6 is received in the upper recessed portion 5a with almost no gap. Each of the strips 5d is provided.

  As shown in FIG. 3, in the assembled state of the slider 6 with respect to the rail 5, the longitudinal direction of the rail 5 (the lateral direction of the horizontally long rectangular plate surface 1a) is caused by the engagement between the ball 8a of the ball plunger 8 and the engagement hole 5c. In contrast, the slider 6 can be positioned at an arbitrary position in units of intervals between the plurality of engagement holes 5c. The slider 6 in the positioning state is prevented from coming off from the rail 5 by the engagement of the circumferential groove 7a of the roller 7 and the protrusion 5d, and further to the rail 5 together with the engagement of the ball 8a and the engagement hole 5c. It will be in the state firmly fixed with respect to it. In this way, the lateral slide mechanism is configured.

  A fixed shaft 10 for mounting the first arm 11 constituting the arm 2 is provided upright at the center of the upper surface of the slider 6. The fixed shaft 10 is fixed by screwing an outward flange 10a formed at the lower end thereof to a slider. A support bracket 12 formed by bending a plate material is fixed to the upper end portion of the fixed shaft 10.

  The support bracket 12 is formed with a pair of upright pieces 12 a that are cut and raised so as to face each other across the fixed shaft 10 at opposite ends of the plate-like portion fixed to the fixed shaft 10. Yes. A lower end portion of a first fixed arm 13 constituting the first arm 11 is provided between the pair of standing pieces 12a, and the first is supported by a support pin 14 provided so as to penetrate between the pair of standing pieces 12a. A lower end portion of the fixed arm 13 is supported.

  The first fixed arm 13 can be rotated around the axis of the support pin 14 by being supported by the support pin 14 as described above. As a result, the first arm 11 can be tilted at an arbitrary angle, but by tightening the nut 15 to the male screw portion formed at the tip of the support pin 14, the first fixed arm 13 is interposed between the pair of upright pieces 12a. The first arm 11 is fixed at that position. In this way, a structure that can be rotated at an arbitrary angle and can be fixed at the rotated position is called rotatable. The mechanism that can be freely rotated and fixed at an arbitrary position is not limited to a mechanism in which a nut is screwed into a screw. For example, two members that rotate relative to each other are pressed against each other via a friction plate, and a friction resistance force is obtained. You may make it rotate with the above force, remove a force, and stop at the position. Further, the lower end portion of the first fixed arm 13 abuts against each inwardly bent stopper piece 12b provided on each of the pair of upright pieces 12a, so that the first fixed arm 13 is in a vertical state with respect to the slider 6, that is, a plate surface. The standing state extending in the vertical direction 1a is maintained.

  A pair of steadying members 16 each having an L-shaped cross section are attached to the slider 6 at both side edge portions along the rail 5 when attached to the rail 5. The steady member 16 is attached to the slider 6 such that one side of the L-shape is screwed to the upper surface 6 a of the slider 6, for example, and the other side is covered with the outer wall surface of the upper recess 5 a of the rail 5. As a result, the outer wall of the upper concave portion 5a of the rail 5 is sandwiched between the slider 6 and the steadying member 16, and the slider 6 is restricted in the width direction perpendicular to the longitudinal direction of the rail 5 (direction perpendicular to the plate surface 1a). Is done.

  FIG. 5 is an exploded perspective view of the main part showing the configuration of the first arm 11 as a vertical slide mechanism. The first fixed arm 13 that extends in the longitudinal direction of the plate surface 1a on the upper surface 6a of the slider 6 has a concave cross-sectional shape as shown in the drawing. A first movable arm 17 having a concave cross-sectional shape that is slightly smaller so as to be movable in the longitudinal direction is attached to the first fixed arm 13 so as to close each other's opening. A pair of protrusions 13a extending in the longitudinal direction opposite to each other are formed on the inner surfaces of the side wall portions in the concave shape of the first fixed arm 13, and are formed on the outer surfaces of the side wall portions in the concave shape of the first movable arm 17. Is formed with a pair of grooves 17a corresponding to the protrusions 13a. The first movable arm 17 is slidably supported only in the longitudinal direction of the first fixed arm 13 by the engagement of the protrusions 13a and the grooves 17a.

  One end of the second arm 18 constituting the arm 2 is supported on the upper end portion of the first movable arm 17. A box-shaped bracket 19 is fixed to the upper end of the first movable arm 17 so as to open upward and on the front side of the plate surface 1a. A support pin 21 is attached to the bracket 19 in a lateral direction perpendicular to the longitudinal direction of the first movable arm 17, and one end of the second arm 18 is rotatably supported by the support pin 21. On the bracket 19 side of the second arm 18, the bottom wall of the box-shaped bracket 19 is restricted so that the extending end side opposite to the support pin 21 is inclined downward and the orthogonal state with the first arm 11 is maintained. A locking piece 18a that abuts on 19a is formed. The support pin 21 is also formed with a male thread at the tip as in the case of the support pin 14 so that the angle (right angle) of both arms 11 and 18 is maintained by tightening the nut 22 to the male thread. It has become.

  In addition, a plurality of engagement holes 13b arranged linearly at equal intervals in the longitudinal direction are provided in both wall portions of the concave shape of the first fixed arm 13. A ball plunger (not shown) similar to the ball plunger 8 is embedded in a corresponding portion of both wall portions of the concave shape of the first movable arm 17, and a part of the ball 22 protrudes. In a state in which the first movable arm 17 is slidably attached to the first fixed arm 13, a plurality of the longitudinal directions of the first fixed arm 13 are engaged by the engagement between the ball 22 of the ball plunger and the engagement hole 13 b. The second movable arm 17, that is, the second arm 18 can be positioned at an arbitrary height in units of the interval between the engagement holes 13b.

  FIG. 6 is an exploded perspective view showing an attachment procedure of the camera 3 attached to the extended end portion of the second arm 18. As shown in the drawing, the back portion of the U-shaped bracket 23 is fixed to the extended end portion of the second arm 18, and the support pins 24 are provided on the pair of opposing pieces of the U-shaped bracket 23. The two arms 18 are attached in a penetrating state in a direction perpendicular to the extending direction of the arms 18. A convex movable bracket 25 is pivotally supported by the support pin 24. The support pin 24 is formed with a male screw portion at the tip as in the case of the support pin 14, and by tightening a nut 26 on the male screw portion, the movable bracket 25 can be attached to the U-shaped bracket 23 at an arbitrary rotation angle. It is supposed to be fixed.

  A pin hole 25 a through which the support pin 24 is inserted is provided in an intermediate portion of the movable bracket 25, and a thin long plate-shaped slide support plate 27 is fixed to the lower surface of the movable bracket 25. In the illustrated example, the pair of scissors formed at the lower end of the movable bracket 25 and the slide support plate 27 are coupled by the pin 28, but may be coupled by bonding or other fastening members. A spacer 30 is interposed between the pair of opposed pieces of the U-shaped bracket 23 and the movable bracket 25.

  The slide support plate 27 is provided with a pair of left and right slots 27a along the longitudinal direction, and one slot 27b arranged in the extending direction at an intermediate portion of the pair of slots 27a in parallel with each other. Yes. A pair of guide pins 29 inserted into the pair of slots 27 a are implanted on the upper surface of the main body case 31 of the camera 3, and a hand screw 32 having a large-diameter head inserted into one slot 27 b is a main body case 31. It is designed to be screwed into the top surface of.

  The state where the components shown in FIG. 6 are assembled and assembled is the state shown in FIG. 2, and the camera fixing member is thus configured. In the assembled state of the figure, the main body case 31 of the camera 3 can rotate around the pivot pin 24 with respect to the plate surface 1a, but a pair of mirror images is provided on both side surfaces of the movable bracket 25 in order to restrict the rotation range. An arc-shaped groove 25b is provided, and a pair of restricting pins 23a projecting from the pair of opposed pieces of the U-shaped bracket 23 so as to project into the arc-shaped groove 25b in an assembled state.

  Further, a ball plunger (not shown) similar to the ball plunger 8 is embedded in the center of the back surface portion of the U-shaped bracket 23, and a part of the ball 33 protrudes. A part of the outer peripheral surface of the movable bracket 25 (an upper surface opposite to the side on which the slide support plate 27 is attached) is formed in a semi-cylindrical surface shape having the pin hole 25a as a central axis, and the semi-cylindrical surface includes A plurality of engagement holes 25c arranged at equal intervals over a predetermined angular range in the circumferential direction are provided. By the engagement between the ball 33 of the ball plunger and the engagement hole 25c, the photographing direction of the camera 3 can be arbitrarily determined in units of intervals between the plurality of engagement holes 25c.

  Next, the internal structure of the camera 3 will be described with reference to FIGS. FIG. 7 is a side sectional view showing the main components of the camera 3, and FIG. 8 is a perspective view showing the main parts of the camera 3 taken out. In the main body case 31, a circuit board 35 on which the image sensor 34 is mounted, a lens unit 36 composed of a combination of a plurality of lenses for condensing light on the image sensor 34, and incident light L1 from the outside And a free-form surface mirror 37 for directing the reflected light L2 to the lens unit 36. The lens unit 36 and the free-form surface mirror 37 are positioned and fixed in the built-in unit case 38, and the circuit board 35 is integrally fixed to the second arm 18 side outside the built-in unit case 38.

  The main body case 31 is provided with an opening 31a through which light passes through the lower surface on the plate surface 1a side in the attached state of FIG. A transparent window 39 for allowing incident light L1 from the plate surface 1a incident from the opening 31a to pass through the free curved mirror 37 is provided on the surface of the built-in unit case 38 facing the opening 31a. Incident light L1 from the plate surface 1a passes through the opening 31a and the window 39 and reaches the free-form surface mirror 37, and the reflected light L2 reflected by the free-form surface mirror 37 is condensed on the image sensor 34 via the lens unit 36. . Since the opening 31a is thus provided on the lower surface of the main body case 31, external light from an illumination device such as a ceiling is difficult to enter the main body case 31, and incident light from the plate surface 1a is mainly contained in the main body case 31. Can be imported.

  The optical axis CL of the lens unit 36 is inclined by a predetermined angle θ1 upstream of the incident direction of the incident light L1 with respect to the optical axis CS of the imaging element 34. Further, the intersection point of the optical axis CL on the imaging surface of the imaging device 34 is deviated from the imaging center 34a of the imaging device 34 by a predetermined distance d1. Further, as shown in FIG. 7, the free-form surface mirror 37 has a YZ plane between a mirror Z axis (Zm) oriented away from the image sensor 34 and a mirror Y axis (Ym) oriented away from the imaging center 34a by a predetermined distance d1. It is curved on the XY plane of the mirror X axis (Xm in FIG. 8) and the mirror Y axis (Ym) in the front and back direction of the paper surface of FIG. 7 orthogonal to both axes Ym and Zm. .

  The mirror Z axis (Zm) is inclined by a predetermined angle θ2 with respect to the optical axis CL of the lens unit 36 on the downstream side in the final vehicle direction of the incident light L1. The mirror origin 37a is deviated from the optical axis CL of the lens unit 36 by a predetermined distance d2 in the same direction as the direction of the deviation d1.

  In the photographing apparatus configured as described above, as shown in FIG. 1, the camera 3 can be installed at a position on the front side and the upper side of the plate surface 1a to photograph the plate surface 1a. In the camera 3 of the photographing apparatus according to the present invention, the image sensor 34 can be arranged on the plate surface 1a side by refracting the optical path using the free-form surface mirror 37, and further, the free-form surface of the concave mirror as in the illustrated example. The mirror 37 can correct the distortion of the screen accompanying the increase in the angle of view. As a result, a wide-angle image can be taken with a short focus.

  FIG. 9 is a side view showing a photographing state of the plate surface 1a by the photographing apparatus to which the present invention is applied. As shown in the figure, the outside of the area of the plate surface 1a (the entire region when the plate surface 1a is viewed from the front) (upward in the figure) and at a position spaced apart from the plate surface 1a in the vertical direction of the plate surface 1a. A camera 3 is arranged. Therefore, although the plate surface 1a is photographed by the camera 3 from obliquely above the plate surface 1a, the camera 3 is positioned at a distance D1 close to the plate surface 1a due to the configuration of the camera 3 using the free-form curved mirror 37 described above. can do.

  In contrast, when the same lens unit 36 and the image sensor 34 are used without using the free-form mirror 37 and the camera 41 having a conventional structure in which the incident side of the lens unit 36 is disposed toward the plate surface 1a is used for photographing. As shown by the two-dot chain line in FIG. 9, it was not possible to photograph on the screen with the same angle of view unless the camera 41 was positioned at a distance D2 far from the plate surface 1a. The distance D2 is approximately four times the distance D1.

  Since it is possible to shoot at a position close to the plate surface 1a in this way, the length of the second arm 18 corresponding to the length of the arm 2 from the plate surface 1a can be shortened, and the entire photographic device can be reduced. Compacting can be promoted. Thereby, it can avoid that the arm 2 and the camera 3 become obstructive also in the scene which looks at the board surface 1a from diagonally upwards, for example like a staircase classroom.

  Further, in the case of the cantilever support structure as shown in the example, if the length of the second arm 18 is long, the camera 3 is supported in a suspended state at the extended end portion, so that the weight of the camera 3 fluctuates. As a countermeasure against this, if the strength of the arm 2 is increased, there is a problem that the weight increases and the handling becomes difficult. On the other hand, since the length of the second arm 18 may be short, even if the arm 2 has a necessary and sufficient strength, the weight is not increased, and the handleability is improved in combination with the downsizing.

  On the other hand, in the cantilever support structure of the arm 2, it is difficult to eliminate the assembly error with respect to the design value. Therefore, the shooting position and direction of the camera 3 can be adjusted. The adjustment structure and adjustment procedure will be described below. To do.

  First, with respect to the adjustment with respect to the tilt direction (arrow A in FIG. 9) that is the tilting direction of the camera 3 with respect to the plate surface 1a, the state where the entire plate surface 1a and the photographing region coincide (align) is set as the reference position. When the shooting direction of the camera 3 is tilted, for example, by 1 degree above the plate surface 1a from the position, the shooting region AC is shifted above the plate surface 1a as shown by the two-dot chain line in FIG. In this case, the movement distance of the shift S2 from the lower edge of the plate surface 1a on the side farther from the camera 3 is larger than the shift S1 from the upper edge of the plate surface 1a on the side closer to the camera 3.

  Further, when the shooting direction of the camera 3 is tilted, for example, by 1 degree to the lower side of the plate surface 1a, the shooting area AC is shifted to the lower side of the plate surface 1a as shown by a two-dot chain line in FIG. Also in this case, the movement distance of the deviation S3 from the lower edge of the plate surface 1a on the side farther from the camera 3 is larger than the deviation S3 from the upper edge of the plate surface 1a on the side closer to the camera 3. S4 is larger than the deviation S2.

  In addition, when the imaging area AC is shifted and deviates from the plate surface 1a, the image data of the deviated range cannot be used as the image of the plate surface 1a. The range on the plate surface 1a corresponding to the deviations S2 and S3 cannot be photographed. Accordingly, as an adjustment range for the tilt direction of the camera 3, an adjustment range of a tilt angle that can cover the shift S3 with respect to the upper side of the plate surface 1a and cover the shift S2 with respect to the lower side of the plate surface 1a is set. That's fine.

  The tilt adjustment is performed by positioning the movable bracket 25 in the rotational direction with respect to the second arm 18 (the U-shaped bracket 23). Specifically, the nut 26 is slightly loosened, the photographing direction of the camera 3 is determined while photographing with the camera 3 and checking on the monitor, and the nut 26 is tightened at that position. If there is a possibility that the nut 26 is slightly moved by tightening the nut 26, fine adjustment with an image processing program is preferably made possible.

  The position where the camera 3 is rotatably supported by the second arm 18 is set on the side of the main body case 31 where the free-form curved mirror 37 is provided. When the main body case 31 is rotated, the rotation center is the axis of the support pin 24, and the rotation center is located in the vicinity of the extension line of the optical axis of the incident light L1. Thereby, when the main body case 31 is rotated, the free-form surface mirror 37 is displaced in a direction intersecting the incident light L1, and the angle of the reflected light L2 with respect to the incident light L1 can be changed. On the other hand, for example, when the length of the second arm 18 is shortened and the position of the support pin 24 is set to the side where the image pickup device 34 of the main body case 31 is provided, the center of rotation is from the optical axis of the incident light L1. It will be far away. In this case, when the main body case 31 is rotated, the free-form surface mirror 37 is displaced in the optical axis direction of the incident light L1, and the angle of the reflected light L2 with respect to the incident light L1 does not change so much. In this case, the optical axis of the reflected light L2 corresponding to the original incident light L1 may not be directed to the image sensor 34, and there is a possibility that image distortion will increase. On the other hand, as described above, the rotation center is positioned in the vicinity of the extension line of the optical axis of the incident light L1, so that the optical axis of the reflected light L2 corresponding to the incident light L1 can be directed to the image sensor 34, and the image is distorted. Can be reduced.

  In addition, since the arm 2 is provided with a hinge coupling between the coupling portion with the slider 6 and the coupling portion between the first arm 11 and the second arm 18, the U-shaped bracket 23 and the movable bracket are provided. As shown by each arrow A in FIG. 2, the rotation adjustment may be similarly performed at other hinge coupling portions as well as the rotation adjustment with respect to 25. The shooting direction of the camera 3 can be adjusted by loosening the nuts 14 and 22 and adjusting the angle of the arm 2, and the arm 22 can be fixed by tightening the nuts 14 and 22 at arbitrary positions. Thus, a mechanism for changing the direction of the camera is configured.

  When the shooting direction of the camera 3 is tilted by 1 degree to the right side of the plate surface 1a, for example, the shooting region AC is shifted to the right side of the plate surface 1a as shown by a two-dot chain line in FIG. . In this case, the deviation S6 from the left side of the plate surface 1a is larger than the deviation S5 from the right edge of the plate surface 1a.

  Also in this case, it can be performed by positioning the slider 6 with respect to the rail 5 in the sliding direction. Specifically, the slider 6 is moved while monitoring on the monitor in the same manner as described above, and the ball 8a is engaged with the engagement hole 5c at the position closest to the position where the image of the plate surface 1a and the screen are aligned, thereby positioning. To do.

  Although the example in which the adjustment of the vertical displacement (vertical direction) S2 and S3 of the plate surface 1a is performed by the tilt adjustment of the camera 3 has been described above, the adjustment is performed by the height adjustment of the camera 3 without the tilt adjustment. Also good. The height adjustment will be described next.

  As described above, the first arm 11 includes the first fixed arm 13 and the first movable arm 17, and the first movable arm 17 can be slid in the vertical direction with respect to the first fixed arm 13. By moving the first movable arm 17 telescopically in and out of the longitudinal direction of the first fixed arm 13, the first movable arm 17 can be positioned at the position of the arbitrary engagement hole 13b as described above. In the configuration of the first arm 11, since the first fixed arm 13 extends above the plate surface 1a, the first movable arm 17 can slide within the range above the plate surface 1a. Accordingly, the moving range of the first movable arm 17, that is, the camera 3, does not interfere with the plate surface 1a.

  For example, the size of the plate surface 1a is about 1750 mm in width and about 900 mm in length, and the position of the opening 31a of the camera 3 is about 200 mm in the vertical direction from the plate surface 1a and in the height direction from the upper edge of the plate surface 1a. FIG. 11A shows a change in the photographing area AC shift S2 due to a difference in the tilt direction of the camera 3 and the change in the photographing area AC shift S2 due to a difference in the height direction of the camera 3. As shown in FIG.

  In FIG. 11A, the adjustment amount at any of the hinges (between the arm 2 and the slider 6, between the first arm 11 and the second arm 18, and between the second arm 18 and the movable bracket 25). (Amount of change in angle between adjacent members) is taken on the horizontal axis, and the amount of change in the imaging area AC is taken on the vertical axis. An angle adjustment amount of 0 is a state in which the center line in the shooting direction of the camera 3 coincides with a plane including an axis orthogonal to the plate surface 1a, that is, a state where the plate surface 1a and the camera 3 face each other. Moreover, the horizontal axis of FIG.11 (b) is the adjustment amount of the height direction of the 1st movable arm 17, and a vertical axis | shaft is the same as Fig.11 (a). The height adjustment amount 0 is the lowest point position in the slide range of the second movable arm 18 with respect to the first fixed arm 13.

  In the case of adjusting the tilt (angle) of the camera 3, as shown in FIG. 11A, when the hinge adjustment amount is 1 degree, the change amount of the imaging area AC is about 450 mm, but the intermediate angle ( It is about 150 mm at 0.5 degrees in the figure, and changes to a curved line that is convex downward. On the other hand, when the height (slide) of the camera 3 is adjusted, it changes linearly as shown in FIG. 11B, and when the height adjustment amount is 400 mm, the change amount of the imaging area AC is about 450 mm. It became. Thus, if the adjustment amount of the hinge is practically 1 degree, it is possible to cope with the adjustment of the displacement without any problem, and it is possible to cope with the height adjustment instead of the angle adjustment of the hinge. As described above, in the angle adjustment of the hinge, the movement amount of the imaging area AC is greatly changed by a slight angle adjustment. In particular, the adjustment is difficult due to the large change at the intermediate angle in FIG. In the adjustment, since the photographing area AC can be adjusted with a change amount equivalent to the change amount, a fine adjustment is facilitated.

  Instead of the height adjustment, the body case 31 may be slid in the extending direction of the second arm 18 as indicated by an arrow B in FIG. In this case, the hand screw 32 is loosened, the main body case 31 is slid in the direction of the arrow B in FIG. 9 with respect to the slide support plate 27, and the hand screw 32 is tightened at an arbitrary position. 31 is fixed. Thereby, the distance from the plate surface 1a of the camera 3 can be changed, and the imaging region can be changed accordingly. Further, each adjustment method may be combined. For example, when the imaging area AC is greatly changed with respect to the plate surface 1a, the adjustment is first made to a rough position by adjusting the angle of the hinge, and then the height is increased. It is possible to adjust with high accuracy by slide adjustment and slide adjustment.

  FIG. 12 is a diagram showing another example of photographing by the camera 3 of the present invention. In the above example, the imaging of the plate surface 1a has been described. However, the support structure of the camera 3 according to the present invention can be applied to imaging in a direction different from the plate surface 1a (opposite direction, etc.). As shown in the drawing, for example, when a meeting is held on the side of the desk 42 that is placed in front of the plate surface 1a, the state of the participant M or the like can be photographed. When the high-resolution camera 3 is used, a document on the desk 42 can be taken.

  First, the nut 26 fastened to the support pin 24 is loosened to fix the rotating bracket 25, and the camera 3 is brought into a vertical state as shown in the figure. In addition, by setting the angle range in the circumferential direction of the arc-shaped groove 25b described above to 90 degrees, each position of a horizontal position for photographing the plate surface 1a and a vertical position for photographing a place away from the plate surface 1a, This can be selectively determined by rotating the movable bracket 25 until the restricting pin 23a comes into contact with either of the circumferential ends of the arc-shaped groove 25b. In this state, the nut 26 is tightened to fix the camera 3.

  When the camera 3 is set in a vertical state as shown in FIG. 12, a predetermined range on the side opposite to the plate surface 1a can be photographed as shown by the solid line in the figure. Thereby, a video can be sent to a remote place in the same manner as a video conference. For example, the versatility of the photographing apparatus can be enhanced without being specialized for photographing an electronic blackboard.

  Furthermore, since the main body case 31 of the camera 3 is attached to the slide support plate 27 as described above, the main body case 31 can be slid along the surface of the slide support plate 27. Specifically, the hand screw 32 can be loosened and the main body case 31 can be slid within the longitudinal length of the slot 27a, and the hand screw 32 can be retightened at an arbitrary position so that the main body case 31 31, that is, the camera 3 can be fixed.

  As a result, for example, as indicated by the two-dot chain line in FIG. 12, the second arm 18 can be moved further upward with respect to the height position. Can be taken. In this case, it is possible to change the height of the second arm 18, but the lower part of the main body case 31 can be positioned below the second arm 18, so that it is preferable to lift the main body case 31. There is an advantage that the work is performed at a low position and is easy to work.

  Further, as described above, since the slider 6 is movably supported by the rail 5 extending along the upper edge of the plate surface 1a, the camera 3 (slider 6) is moved in the left-right direction from the center position. be able to. For example, as shown in FIG. 13, when the camera 3 is positioned on the left side when viewed from the directly facing position of the plate surface 1a, the plate surface 1a to be the imaging region AC1 indicated by the broken line in the drawing of the plate surface 1a. The left half area can be photographed. In this case, since the rail 5 is attached to the upper edge of the frame 4 that surrounds the plate surface 1a, the distance from the plate surface 1a of the camera 3 and the shooting direction with respect to the plate surface 1a remain constant. Since the camera 3 can be moved integrally with the slider 6, when the shooting state is adjusted at the horizontal center position of the plate surface 1a, the shooting at the position moved in the horizontal direction can be performed without changing the adjustment. It can be carried out.

  Further, as shown in the figure, the image capturing area may be narrowed and imaged so as to target the area (AC1) half of the plate surface 1a by known image processing. Further, a narrower imaging area AC2 indicated by the two-dot chain line in the figure can be taken by the tilt adjustment or the like. By setting such a narrow shooting area (AC1 and AC2) as a shooting target, it is possible to enlarge characters, graphics, and the like in the area by image processing, and to facilitate recognition on the monitor. The camera 3 (slider 6) can be moved within a predetermined range (arrow C in FIG. 13) in the left-right direction across the center position of the plate surface 1a, and the right side portion of the plate surface 1a on the opposite side of FIG. Can be taken in the same way.

  Further, as shown in FIGS. 1 and 9, a tray 1b for placing a marker pen and an eraser is provided at the lower edge of the whiteboard 1 to the full width (horizontal direction) of the plate surface 1a. In the case where the camera 3 takes a picture from above the plate surface 1a as in the illustrated example, the tray 1b is reflected on the plate surface 1a because the tray 1b is on the opposite side in the shooting direction (the broken line in the figure). Arrow D). Since the reflection on the tray 1b adversely affects the subsequent image processing, the tray 1b is subjected to a process for reducing the reflectance. Specifically, the plate surface 1a side portion of the tray 1b is formed of a black member or painted black. Alternatively, it is preferable to perform a surface treatment for irregular reflection as a rough surface treatment for preventing reflection on the plate surface 1a. The reflection on the plate surface 1a is the same for both side (left and right side) portions 1c of the plate surface 1a. Therefore, it is preferable that the both side portions 1c be formed of a black member or painted black as a process similar to the above. Alternatively, surface treatment for irregular reflection may be performed.

  The present invention has been described with reference to the preferred embodiments. However, as those skilled in the art can easily understand, the present invention is not limited to such embodiments, and the gist of the present invention. As long as it does not deviate from the above, it can be appropriately changed.

  For example, as shown in FIG. 14, the upper surface 42a as the plate surface of the desk 42 can be photographed in the same manner as described above. The arm 2 is provided so as to extend laterally from one side of the desk 42 and extend upward, and is fixed to the desk 42, and the upper surface 42 a is photographed obliquely from above by the camera 3. Thereby, the character etc. which were written in the board and paper mounted in the upper surface 42a can be projected on the monitor of a personal computer similarly to the above. In this case, the adjustment of the photographing direction by the arm 2 or the like is as described above. In addition, the rail 5 may be fixed to the edge of the desk 42, and in this case, as described above, the camera 3 can be moved in the left-right direction to take an image of an arbitrary area.

In addition, all the components shown in the above embodiment are not necessarily essential, and can be appropriately selected without departing from the gist of the present invention.

  INDUSTRIAL APPLICABILITY The photographing apparatus according to the present invention can easily adjust the photographing direction when photographing a place closer to the camera supported by the arm, and is useful as a photographing apparatus when photographing a board surface such as an electronic blackboard. It is.

DESCRIPTION OF SYMBOLS 1 White board 1a Plate surface 2 Arm 3 Camera 5 Rail 6 Slider 11 First arm 13 First fixed arm 17 First movable arm 18 Second arm 22 Movable bracket 27 Slide support plate 31 Body case 34 Image sensor 36 Lens unit 37 Free-form mirror

Claims (2)

An area photographing device that supports the camera by an arm attached to a member integral with the plate surface and extended toward the front side of the plate surface in order to photograph the plate surface with a camera,
The camera includes an imaging device, a free-form curved mirror for reflecting incident light toward the imaging device, and a lens for condensing the reflected light reflected by the free-form curved mirror on the imaging device. ,
2. The area photographing apparatus according to claim 1, wherein the arm has a mechanism for changing a direction of the camera so as to correct a deviation in a direction along the plate surface from a reference position where a photographing region of the camera is aligned with the whole plate surface. . A base member attached to a member integral with the plate surface;
The arm is supported by the first arm supported by the base member so as to extend outward along the plate surface, and supported by the first arm so as to extend toward the front side of the plate surface. A second arm, and a camera fixing member provided at an extended end of the second arm to fix and support the camera;
Mechanisms for changing the direction of the camera are respectively between the base member and the first arm, between the first arm and the second arm, and between the second arm and the camera fixing member. 2. The area photographing apparatus according to claim 1, wherein the relative angle is adjusted.

Images