Camera support mechanism and image acquisition system

Abstract

This invention provides a camera support mechanism and image acquisition system that can capture images in multiple directions without narrowing the field of view. [Solution] The device comprises a mirror portion 260 that is capable of transmitting light in a first direction to the lens 110 and reflecting light in a second direction to the lens 110; a first liquid crystal shutter 280 that, when open, allows light in the first direction to pass through to the mirror portion 260 and, when closed, blocks the light in the first direction; and a second liquid crystal shutter 290 that, when open, allows light in the second direction to pass through to the mirror portion 260 and, when closed, blocks the light in the second direction. The device is configured to allow switching between a state in which the first liquid crystal shutter 280 is open and the second liquid crystal shutter 290 is closed, and a state in which the first liquid crystal shutter 280 is closed and the second liquid crystal shutter 290 is open.

Description

Technical Field

[0001] The present invention relates to a camera support mechanism and an image acquisition system.

Background Art

[0002] Conventionally, techniques related to photographing using a camera have been known. For example, it is as described in Patent Document 1.

[0003] Patent Document 1 describes a monitoring method in which at least one plane mirror is placed within the field of view of a television camera, and the field of view angle of the television camera is deflected by the plane mirror to monitor two directions with one television camera.

[0004] In the monitoring method described in Patent Document 1, half of the field of view of the television camera is deflected by the plane mirror. Therefore, the field of view (angle of view) in each direction that the television camera can photograph becomes relatively narrow.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The present invention has been made in view of the above circumstances, and the problem to be solved is to provide a camera support mechanism and an image acquisition system that can photograph a plurality of directions without narrowing the angle of view.

Means for Solving the Problems

[0007] The problem to be solved by the present invention is as described above. Next, means for solving this problem will be described.

[0008] That is, claim 1 provides a camera support mechanism for supporting a camera capable of photographing an object, comprising: a mirror portion formed to transmit light in a first direction along the optical axis of the camera lens toward the lens side and to reflect light in a second direction different from the first direction toward the lens side; a first opening / closing portion that, when open, allows light in the first direction to pass toward the mirror portion and, when closed, blocks light in the first direction; and a second opening / closing portion that, when open, allows light in the second direction to pass toward the mirror portion and, when closed, blocks light in the second direction, wherein the mechanism is configured to be switchable between a state in which the first opening / closing portion is open and the second opening / closing portion is closed, and a state in which the first opening / closing portion is closed and the second opening / closing portion is open.

[0009] In claim 2, the first opening / closing section and the second opening / closing section are formed by a liquid crystal shutter.

[0010] Claim 3 comprises a first support portion that rotatably supports the camera about a first pivot axis perpendicular to the optical axis, wherein the first support portion is capable of adjusting the rotational position of the camera about the first pivot axis so as to change the angle between a first field of view based on light transmitted through the mirror portion and a second field of view based on light reflected from the mirror portion, when viewed in the axial direction of the first pivot axis.

[0011] Claim 4 provides a second support portion which supports the first support portion and is formed to be rotatable about a second pivot axis perpendicular to the first pivot axis.

[0012] Claim 5 provides a third support portion which supports the second support portion and is formed to be rotatable about a third pivot axis that is perpendicular to the second pivot axis.

[0013] Claim 6 comprises a camera support mechanism according to any one of claims 1 to 5, a camera, and an image acquisition means that acquires an image of the camera based on light transmitted through the mirror while the first opening / closing part and the second opening / closing part are operated to allow light in the first direction to pass through and block light in the second direction, and acquires an image of the camera based on light reflected by the mirror while the first opening / closing part and the second opening / closing part are operated to block light in the first direction and allow light in the second direction to pass through. [Effects of the Invention]

[0014] The present invention provides the following effects:

[0015] In this invention, it is possible to photograph multiple directions without narrowing the field of view. [Brief explanation of the drawing]

[0016] [Figure 1] A block diagram showing an image acquisition system relating to one embodiment of the present invention. [Figure 2] A perspective view showing a camera support mechanism and a camera according to one embodiment of the present invention. [Figure 3] A perspective view showing a camera support mechanism with the housing omitted and a camera. [Figure 4] An exploded perspective view showing the camera support mechanism and camera with the housing omitted. [Figure 5] (a) A plan cross-sectional view showing the camera support mechanism and camera with the first liquid crystal shutter open and the second liquid crystal shutter closed. (b) A bottom view showing the mirror support and camera support. [Figure 6] A plan cross-sectional view showing the camera support mechanism and camera in the state where the first liquid crystal shutter is closed and the second liquid crystal shutter is open. [Figure 7] (a) A schematic plan view showing the state of photographing the passageway using the camera support mechanism in the reference direction. (b) A schematic plan view showing the camera support mechanism in the reference direction. [Figure 8](a) A plan view schematically showing a state where a passage is being photographed using a camera support mechanism with the viewing direction adjusted from a reference direction. (b) A plan view schematically showing the camera support mechanism with the viewing direction adjusted.

Mode for Carrying Out the Invention

[0017] Hereinafter, the video acquisition system 1 and the camera support mechanism 200 according to an embodiment of the present invention will be described. In the following description, the vertical direction, the horizontal direction, and the front - rear direction are defined according to the arrows shown in the figures.

[0018] The video acquisition system 1 shown in FIG. 1 acquires video of a shooting target using the camera 100. In this embodiment, as the shooting target, the passage 2 shown in FIG. 7(a) is adopted. The passage 2 is formed in a substantially L - shaped plane view by a first passage 2a and a second passage 2b that are orthogonal to each other. The first passage 2a is formed to extend in the front - rear direction. The second passage 2b is formed to extend rightward from the rear end portion of the first passage 2a.

[0019] The video acquisition system 1 can be used for monitoring a shooting target. Hereinafter, an example of using the video acquisition system 1 for monitoring a pedestrian walking in the passage 2 will be described. The video acquisition system 1 is applicable, for example, to the passage 2 in an elderly facility. When the video acquisition system 1 is applied to an elderly facility, the video captured by the camera 100 can be used for verifying the walking motion of the pedestrian, etc. The video acquisition system 1 includes a camera 100, a camera support mechanism 200, and video acquisition means 300.

[0020] The camera 100 shown in Figures 3 and 5 is capable of capturing video of the subject being filmed. For example, a non-interlaced scan (progressive scan) camera can be used as the camera 100. However, the camera 100 is not limited to the examples described above; various cameras suitable for monitoring can be used. The camera 100 has a lens 110. In this embodiment, an example is shown where the lens 110 of the camera 100 is pointed forward. In Figure 5(a), the optical axis X of the lens 110 is shown by a dashed line.

[0021] The camera support mechanism 200 shown in Figures 2 to 5 supports the camera 100 so that it can photograph the first passage 2a and the second passage 2b. The camera support mechanism 200 is installed on a predetermined installation site. In this embodiment, the ceiling of passage 2 is used as the installation site. The camera support mechanism 200 is formed so that the direction in which the lens 110 of the camera 100 faces can be adjusted. In the following description of the camera support mechanism 200, the configuration will be explained with reference to the camera support mechanism 200 in a position where the optical axis X of the lens 110 of the camera 100 is oriented horizontally (hereinafter referred to as the "reference position").

[0022] The camera support mechanism 200 comprises a base plate 210, a pan arm 220, a tilt arm 230, a camera support section 240, a mirror support section 250, a mirror section 260, a housing 270, a first liquid crystal shutter 280, and a second liquid crystal shutter 290. Note that the housing 270, the first liquid crystal shutter 280, and the second liquid crystal shutter 290 are not shown in Figures 3 and 4.

[0023] The base plate 210 shown in Figures 2 to 4 is the part that is attached to the installation target (ceiling). The base plate 210 is formed in a roughly plate shape with the plate surface oriented in the vertical direction. The base plate 210 has a pan shaft 211.

[0024] The pan shaft 211 is an axis oriented vertically. The pan shaft 211 is provided so as to protrude downward from the lower surface of the base plate 210.

[0025] The pan arm 220 shown in Figures 3 and 4 is connected to the base plate 210, and a tilt arm 230, which will be described later, is also connected to it. The pan arm 220 is rotatably connected to the base plate 210 around the pan shaft 211. The pan arm 220 is formed by bending a substantially plate-shaped member into a substantially L-shape. The pan arm 220 comprises a first part 221 and a second part 222. The first part 221 and the second part 222 each constitute a substantially L-shaped piece.

[0026] The first portion 221 is the part that connects to the base plate 210. The first portion 221 is formed to extend horizontally. The first portion 221 is positioned so that its plate surface is parallel to the plate surface of the base plate 210. The first portion 221 has a pan adjustment section 221a.

[0027] The pan adjustment section 221a is capable of adjusting the angle of the pan arm 220 around the pan shaft 211. The pan adjustment section 221a is provided at one end of the first section 221 in the extending direction. The pan adjustment section 221a is formed on the upper surface of the first section 221. The pan adjustment section 221a has a hole through which the pan shaft 211 is inserted.

[0028] The pan adjustment section 221a is formed to allow for the restriction and release of the rotation of the pan arm 220 around the pan shaft 211. The pan adjustment section 221a is provided with an operating section 221b for performing the operation of restricting and releasing the rotation. As the operating section 221b, for example, a screw member that can restrict the rotation of the pan arm 220 by tightening can be used. In this case, the rotation of the pan arm 220 around the pan shaft 211 can be allowed by loosening the operating section 221b. Note that the pan adjustment section 221a is not limited to the example described above, and various mechanisms that can restrict and release rotation can be used.

[0029] The second part 222 is the part to which the tilt arm 230, described later, is connected. The second part 222 is formed to extend downward from the other end of the first part 221 in the extension direction (the end on the side of the anti-pan adjustment part 221a). The plate surface of the second part 222 is positioned perpendicular to the plate surface of the first part 221. The second part 222 has a tilt axis 222a.

[0030] The tilt axis 222a is an axis whose axis is oriented horizontally. The tilt axis 222a is provided so as to protrude horizontally from the inner surface of the second part 222 (the surface facing the center of the camera support mechanism 200 in a plan view).

[0031] The tilt arm 230 shown in Figures 3 and 4 is connected to the pan arm 220, and also to the camera support section 240 and mirror support section 250, which will be described later. The tilt arm 230 is connected to the pan arm 220 so as to be rotatable about the tilt axis 222a. The tilt arm 230 is formed in the shape of a substantially plate-shaped member bent into a substantially L-shape. The tilt arm 230 comprises a first part 231 and a second part 232. The first part 231 and the second part 232 each constitute a substantially L-shaped piece.

[0032] The first portion 231 is the part connected to the pan arm 220. The first portion 231 is formed to extend in a direction perpendicular to the tilt axis 222a (up and down in the reference position). As shown in Figures 3 and 4, in the reference position, the extension direction of the first portion 231 is the same as the extension direction of the second portion 222 of the pan arm 220. The plate surface of the first portion 231 is positioned parallel to the plate surface of the second portion 222. The first portion 231 has a tilt adjustment section 231a.

[0033] The tilt adjustment section 231a is capable of adjusting the angle of the tilt arm 230 around the tilt axis 222a. The tilt adjustment section 231a is provided at one end (the upper end in the illustrated example) in the extending direction of the first section 231. The tilt adjustment section 231a is provided on the inner surface of the first section 231 (the surface facing the center of the camera support mechanism 200 in a plan view). A hole is formed in the tilt adjustment section 231a through which the tilt axis 222a is inserted.

[0034] The tilt adjustment section 231a is configured to allow restriction and release of the rotation of the tilt arm 230 around the tilt axis 222a. The tilt adjustment section 231a is provided with an operating section 231b for performing the operation of restricting and releasing the rotation. The tilt adjustment section 231a and the operating section 231b can be configured in a manner generally similar to that of the pan adjustment section 221a and the operating section 221b of the pan arm 220.

[0035] The second part 232 is the part to which the camera support part 240 and the mirror support part 250, which will be described later, are connected. The second part 232 is formed to extend horizontally (in the direction of projection of the tilt axis 222a) from the other end (the lower end in the illustrated example) of the first part 231 in the extension direction. The plate surface of the second part 232 is arranged to be perpendicular to the plate surface of the first part 231. The second part 232 has an adjustment axis 232a.

[0036] The adjustment shaft 232a is an axis whose axis is oriented perpendicular to the tilt axis 222a. In the reference position, the adjustment shaft 232a is positioned so that its axis is oriented vertically. The adjustment shaft 232a is provided so as to protrude upward from the upper surface of the extension end of the second part 232. The adjustment shaft 232a is the center of rotation of the camera support part 240, which will be described later.

[0037] The camera support section 240 shown in Figures 3 to 5 is connected to the tilt arm 230 and supports the camera 100. The camera support section 240 is rotatably connected to the tilt arm 230 around the adjustment shaft 232a. The camera support section 240 comprises a support section 241 and a field of view adjustment section 242.

[0038] The support portion 241 is the part that supports the camera 100. The support portion 241 is positioned on the upper part of the second portion 232 of the tilt arm 230. The support portion 241 comprises a first portion 241a, a second portion 241b, and a third portion 241c. Each of these portions is formed in a roughly plate shape.

[0039] The first portion 241a is the part connected to the tilt arm 230. The first portion 241a is formed to extend in a direction perpendicular to the adjustment shaft 232a (the front-rear direction in the illustrated example). The plate surface of the first portion 241a is positioned parallel to the plate surface of the second portion 232 of the tilt arm 230. A hole is formed at one end (front end) of the first portion 241a in the extending direction through which the adjustment shaft 232a is inserted.

[0040] The second part 241b is a portion that extends from the other end (rear end) of the first part 241a in the direction of extension, in a direction perpendicular to the direction of extension of the first part 241a (upward).

[0041] The third portion 241c is the portion to which the camera 100 is fixed. The third portion 241c is formed to extend horizontally from the leading edge (upper end) of the second portion 241b toward the side opposite the adjustment axis 232a (rear). In this embodiment, the camera 100 is fixed to the upper surface of the third portion 241c.

[0042] The field of view adjustment unit 242 is capable of adjusting the rotational position of the camera support unit 240 around the adjustment shaft 232a. By rotating the camera support unit 240 around the adjustment shaft 232a, the direction of the direct field of view A and the reflected field of view B of the camera 100, which will be described later, can be adjusted. The adjustment of each of the above fields of view will be described later. The field of view adjustment unit 242 has a worm holding unit 242a and a worm shaft 242b.

[0043] The worm retaining portion 242a rotatably holds the worm shaft 242b, which will be described later. The worm retaining portion 242a is provided on the upper surface of the first portion 241a.

[0044] The worm shaft 242b engages with the gear portion 251a of the worm wheel 251, which will be described later. The worm shaft 242b, together with the worm wheel 251, constitutes a worm gear. The worm shaft 242b is rotatably held relative to the worm holding portion 242a, with its axis oriented horizontally as the center of rotation. The worm shaft 242b has a shaft portion on which screw-shaped teeth are formed to engage with the gear portion 251a. The worm shaft 242b also has a head portion that expands in diameter relative to the shaft portion.

[0045] The mirror support section 250 shown in Figures 3 to 5 is connected to the tilt arm 230 and supports the mirror section 260, which will be described later. The mirror support section 250 is positioned on the upper part of the first portion 241a of the camera support section 240. The mirror support section 250 is fixed to the adjustment shaft 232a of the tilt arm 230 in a way that prevents rotation. The mirror support section 250 comprises a worm wheel 251 and a support section 252.

[0046] The worm wheel 251 is the part that is fixed to the adjustment shaft 232a. The worm wheel 251 is formed in a substantially cylindrical shape. A hole is formed in the center of the worm wheel 251 in a plan view, through which the adjustment shaft 232a is inserted. The worm wheel 251 is fixed to the adjustment shaft 232a inserted through the hole so as not to rotate. The worm wheel 251 comprises a gear portion 251a and a reduced diameter portion 251b.

[0047] The gear portion 251a is the part that engages with the worm shaft 242b of the camera support portion 240. The gear portion 251a constitutes a gear that engages with the screw-shaped teeth of the worm shaft 242b of the field adjustment portion 242. The gear portion 251a constitutes the upper part of the worm wheel 251.

[0048] The reduced-diameter portion 251b is the part that is smaller in diameter than the gear portion 251a. The reduced-diameter portion 251b constitutes the lower part of the worm wheel 251. The reduced-diameter portion 251b has a notch portion 251c.

[0049] The notch 251c shown in Figure 5(b) is formed by cutting out a portion of the lower surface of the reduced-diameter portion 251b. The first portion 241a of the support portion 241 is housed in the notch 251c. The notch 251c is formed to allow rotation of the support portion 241 (camera support portion 240) within a certain range.

[0050] The support portion 252 is the part that supports the mirror portion 260, which will be described later. The support portion 252 is fixed to the upper surface of the gear portion 251a of the worm wheel 251. The support portion 252 is formed to extend upward.

[0051] As described above, the camera support section 240 is formed to be rotatable about the adjustment shaft 232a relative to the mirror support section 250. Specifically, the worm shaft 242b of the field of view adjustment section 242 provided on the camera support section 240 and the worm wheel 251 provided on the mirror support section 250 constitute a worm gear that engages with each other. When the worm shaft 242b is rotated, the rotational force of the worm shaft 242b is converted into a force that rotates the camera support section 240 about the adjustment shaft 232a.

[0052] As shown in Figure 5(b), the camera support portion 240 according to this embodiment is formed to be rotatable within the range in which the notch portion 251c of the worm wheel 251 is formed. Furthermore, the first portion 241a of the camera support portion 240 abuts against the notch portion 251c, thereby restricting rotation beyond the above range.

[0053] The mirror portion 260 shown in Figures 3 to 5 has both light-transmitting and reflective properties (half-mirror or magic mirror). The mirror portion 260 can reflect a portion of the incident light and transmit the other portion. In this embodiment, a half-mirror with equal reflectivity and transmittance is used as the mirror portion 260. Note that the reflectivity and transmittance of the mirror portion 260 are not limited to the examples described above, and various values ​​can be set.

[0054] The mirror portion 260 is fixed to the support portion 252. The mirror portion 260 is positioned to face the lens 110 of the camera 100. As shown in Figures 4 and 5(a), the mirror portion 260 is positioned obliquely to the optical axis X of the lens 110. In the example shown, in a plan view, the angle formed by the surface of the mirror portion 260 facing the lens 110 (reflective surface) and the optical axis X of the lens 110 is approximately 45°.

[0055] As shown in Figure 5(a), the mirror portion 260 according to this embodiment can transmit light in a direction along the optical axis X of the lens 110 of the camera 100 (light from the front in the illustrated example) towards the lens 110. Also, as shown in Figure 6, the mirror portion 260 can reflect light in a different direction (light from the right in the illustrated example) towards the lens 110. In this embodiment, the transmission and reflection of light by the mirror portion 260 can be switched by changing the brightness of the space of the housing 270 partitioned by the mirror portion 260. A detailed explanation of the switching between transmission and reflection of light will be given later.

[0056] The housing 270 shown in Figures 2 and 5(a) constitutes the enclosure of the camera support mechanism 200. The housing 270 is formed in a roughly box shape capable of housing the camera 100, the camera support part 240, the mirror support part 250, and the mirror part 260 inside. A hole is formed in the lower part (bottom) of the housing 270 through which the adjustment shaft 232a is inserted. The housing 270 is fixed to the upper surface of the second part 232 of the tilt arm 230. The housing 270 comprises a camera housing part 271, a first shutter housing part 272, and a second shutter housing part 273.

[0057] The camera housing section 271 shown in Figure 5(a) is the part that houses the camera 100, the camera support section 240, the mirror support section 250, and the mirror section 260. The camera housing section 271 constitutes the left rear corner of the housing 270. The camera housing section 271 is formed in a substantially rectangular shape in plan view.

[0058] The first shutter housing section 272 is the part that houses the first liquid crystal shutter 280, which will be described later. The first shutter housing section 272 is located in front of the camera housing section 271. The first shutter housing section 272 is formed to widen in the vertical and horizontal directions as it extends forward, corresponding to the field of view of the camera 100. The first shutter housing section 272 has an opening 272a that opens forward and is provided with the first liquid crystal shutter 280, which will be described later.

[0059] The second shutter housing section 273 is the part that houses the second liquid crystal shutter 290, which will be described later. The second shutter housing section 273 is located to the right of the camera housing section 271. The first shutter housing section 272 is formed to widen in the vertical and horizontal directions as it moves to the right, corresponding to the field of view of the camera 100. The second shutter housing section 273 has an opening 273a that opens to the right and is provided with the second liquid crystal shutter 290, which will be described later.

[0060] As shown in Figure 5(a), the first shutter housing section 272 and the second shutter housing section 273 are separated by the mirror section 260.

[0061] The first liquid crystal shutter 280 is capable of controlling the transmittance of light from the front. The first liquid crystal shutter 280 is formed so that its transmittance changes depending on the applied voltage. The first liquid crystal shutter 280 is formed in a substantially plate shape with its plate surface facing in the front-to-back direction. The first liquid crystal shutter 280 is positioned to close the opening 272a of the first shutter housing 272. As shown in Figure 5(a), when the first liquid crystal shutter 280 is open (the transmittance of the first liquid crystal shutter 280 is increased), light from the front can pass through to the mirror section 260. On the other hand, as shown in Figure 6, when the first liquid crystal shutter 280 is closed (the transmittance of the first liquid crystal shutter 280 is decreased), light from the front can be blocked.

[0062] The second liquid crystal shutter 290 is capable of controlling the transmittance of light coming from the right. The second liquid crystal shutter 290 is configured in much the same way as the first liquid crystal shutter 280. The second liquid crystal shutter 290 is positioned with its plate surface facing left to right. The second liquid crystal shutter 290 is positioned to close the opening 273a of the second shutter housing 273. As shown in Figure 6, when the second liquid crystal shutter 290 is open, light coming from the right can pass through to the mirror section 260. On the other hand, as shown in Figure 5(a), when the second liquid crystal shutter 290 is closed, light coming from the right can be blocked.

[0063] The configuration of the camera support mechanism 200 has been described above. Below, the positional relationships of the various parts (pan arm 220, tilt arm 230, camera support section 240, mirror support section 250, etc.) that make up the camera support mechanism 200 will be described. In the plan views used in the following description (Figure 5(a), etc.), the point indicating the center of the adjustment shaft 232a is shown as center O.

[0064] As shown in Figure 5(a), the optical axis X of the lens 110 of the camera 100 passes through the center O in a plan view (perpendicular to the axis of the adjustment axis 232a). Also as shown in Figure 5(a), the mirror section 260 is positioned such that a portion of its reflective surface lies on the center O (axis of the adjustment axis 232a) in a plan view. Also as shown in Figure 5(a), the tilt axis 222a is positioned such that its axis (indicated by the dashed line) passes through the center O in a plan view. Furthermore, in the reference position, the adjustment axis 232a is approximately coaxial with the pan axis 211 (see Figure 4). In other words, in the reference position, the pan axis 211 passes through the center O.

[0065] The camera 100 and camera support mechanism 200 described above constitute a camera unit capable of shooting in multiple directions (two directions). The shooting modes using the camera 100 and camera support mechanism 200 will be explained later.

[0066] Next, the image acquisition means 300 will be described with reference to Figure 1. The image acquisition means 300 acquires images of the first passage 2a and the second passage 2b using the camera unit (camera 100 and camera support mechanism 200) as described above. The image acquisition means 300 is configured to communicate with the camera 100, the first liquid crystal shutter 280 and the second liquid crystal shutter 290. The image acquisition means 300 comprises a frame counter 310, a shutter drive device 320, an image switching device 330, a first image processing device 340 and a second image processing device 350.

[0067] The frame counter 310 counts the frames (frame rate) of the video captured by the camera 100 based on the signal (synchronization signal) acquired from the camera 100.

[0068] The shutter drive device 320 controls the alternating opening and closing of the first liquid crystal shutter 280 and the second liquid crystal shutter 290 for each frame counted by the frame counter 310. In this embodiment, when the number of frames is even, the shutter drive device 320 opens the first liquid crystal shutter 280 and closes the second liquid crystal shutter 290. On the other hand, when the number of frames is odd, the shutter drive device 320 closes the first liquid crystal shutter 280 and opens the second liquid crystal shutter 290.

[0069] The video switching device 330 acquires video (video signal) from the camera 100 and transmits the video signal to the first image processing device 340 and the second image processing device 350, which will be described later, based on the number of frames counted by the frame counter 310. The video switching device 330 transmits video signals with an even number of frames to the first image processing device 340. On the other hand, the video switching device 330 transmits video signals with an odd number of frames to the second image processing device 350.

[0070] The first image processing device 340 performs image processing using a video signal with an even number of frames. The first image processing device 340 can form an image using the above video signal.

[0071] The second image processing device 350 performs image processing using a video signal with an odd number of frames. The second image processing device 350 can form an image using the above video signal. Here, since the image with an odd number of frames is an image based on light reflected by the mirror unit 260, it is a mirror image that is inverted left to right. The second image processing device 350 can perform image processing to correct the above mirror image.

[0072] Each device of the above-mentioned video acquisition means 300 can be formed by a control device (for example, a server or a personal computer) capable of processing various types of information.

[0073] The configuration of the video acquisition system 1 according to this embodiment has been described above. The following describes the methods of shooting using the video acquisition system 1.

[0074] In the following explanation, we will use an example in which the camera support mechanism 200 is installed on the ceiling of the passage 2 so that it is located at the corners of the first passage 2a and the second passage 2b in a plan view, as shown in Figure 7(a).

[0075] Furthermore, the following describes an example in which the direction around each axis (pan axis 211, tilt axis 222a, and adjustment axis 232a) of each part constituting the camera support mechanism 200 (pan arm 220, tilt arm 230, camera support part 240, mirror support part 250) is defined as the "reference direction" shown in Figures 5(a) and 7.

[0076] In the camera support mechanism 200 in the reference direction, the axis of the tilt axis 222a (shown in Figure 5(a), a double-dash line tilted 45° to the left with respect to the optical axis X) is positioned perpendicular to the plane that bisects the first passage 2a and the second passage 2b (see the dashed line tilted 45° to the right with respect to the optical axis X, shown in Figure 7(a)).

[0077] In the image acquisition system 1 according to this embodiment, the first passage 2a and the second passage 2b can be photographed alternately by switching the opening and closing of the first liquid crystal shutter 280 and the second liquid crystal shutter 290. The opening and closing of the first liquid crystal shutter 280 and the second liquid crystal shutter 290 is performed by the shutter drive device 320.

[0078] Specifically, as shown in Figure 5(a), when the first liquid crystal shutter 280 is open and the second liquid crystal shutter 290 is closed, the side of the housing 270 where the first shutter is housed becomes brighter, while the side where the second shutter is housed becomes darker.

[0079] In this case, the light from the front that has passed through the first liquid crystal shutter 280 passes through the mirror section 260 and enters the lens 110 of the camera 100. As a result, the camera 100 can take pictures with a direct field of view A, which is a field of view based on the light that has passed through the mirror section 260 (a field of view centered on the optical axis X of the lens 110). In Figure 5(a), the direct field of view A is shown as a dashed line, and the optical axis X is shown as a dashed line.

[0080] As shown in Figures 5(a) and 7(a), in the camera support mechanism 200 in the reference direction, the optical axis X of the camera 100 is oriented in a direction parallel to the first passage 2a (front-to-back direction). With the above camera support mechanism 200, it is possible to photograph the first passage 2a in the direct field of view A.

[0081] On the other hand, as shown in Figure 6, when the first liquid crystal shutter 280 is closed and the second liquid crystal shutter 290 is open, the side of the housing 270 where the first shutter is housed 272 becomes dark, while the side where the second shutter is housed 273 becomes bright. In this case, light from the right that has passed through the second liquid crystal shutter 290 is reflected by the mirror 260 and enters the lens 110 of the camera 100. As a result, the camera 100 can take pictures with the reflected field of view B, which is the field of view based on the light reflected by the mirror 260. In Figure 6, the reflected field of view B is shown by a dashed line, and the reflection axis Y, which is the central axis of the reflected field of view B in a plan view, is shown by a dashed line. The direct field of view A and the reflected field of view B are generally symmetrical with respect to the mirror 260.

[0082] As shown in Figures 6 and 8(a), in the camera support mechanism 200 in the reference direction, the reflection axis Y of the camera 100 is oriented in a direction parallel to the second passage 2b (left-right direction). With the above camera support mechanism 200, it is possible to photograph the second passage 2b in the reflected field of view B.

[0083] As described above, the image acquisition system 1 allows for alternating between capturing images of the first passage 2a in the direct field of view A and capturing images of the second passage 2b in the reflected field of view B by switching the opening and closing of the first liquid crystal shutter 280 and the second liquid crystal shutter 290.

[0084] The video acquisition means 300 of the video acquisition system 1 can acquire images of the first passage 2a and the second passage 2b by synchronizing the capture of images of each field of view by the video switching device 330 and the switching operation of opening and closing the first liquid crystal shutter 280 and the second liquid crystal shutter 290 by the shutter drive device 320 based on the number of frames of the image.

[0085] According to this embodiment, it is possible to capture images using approximately the entire field of view of the camera 100 in both the direct field of view A and the reflected field of view B. Therefore, it is possible to capture images of each passageway without narrowing the field of view of each field of view.

[0086] Furthermore, the camera support mechanism 200 according to this embodiment allows for adjustment of the orientation of the camera 100 and the direction of each field of view.

[0087] Specifically, an operator adjusting the orientation of the camera 100 can rotate the camera 100 around the pan axis 211 by operating the pan adjustment unit 221a to release the rotational restriction. The operator can also fix the orientation of the camera 100 after rotation by operating the pan adjustment unit 221a to restrict the rotation. In this way, the operator can adjust the horizontal orientation of the camera 100.

[0088] Furthermore, the operator can rotate the camera 100 around the tilt axis 222a by operating the tilt adjustment unit 231a to release the rotational restriction. The operator can also fix the orientation of the camera 100 after rotation by operating the tilt adjustment unit 231a to restrict the rotation. In this way, the operator can adjust the vertical orientation of the camera 100.

[0089] Furthermore, the operator can adjust the direction of the direct field of view A and the reflected field of view B of the camera 100 by operating the field of view adjustment unit 242. Specifically, the operator can adjust the rotational position of the camera support unit 240 around the adjustment shaft 232a by operating the worm shaft 242b.

[0090] The following describes an example of changing the direction of each field of view of camera 100 from the state shown in Figure 7 to the state shown in Figure 8. In Figures 7(a) and 8(a), the blind spots of each field of view are shown by filling them in.

[0091] Figure 7 shows an example where the camera support mechanism 200 is the reference direction. In the above example, the angle α formed by the optical axis X, which is the central axis of the direct field of view A in plan view, and the reflective axis Y, which is the central axis of the reflected field of view B, is approximately 90° (see Figure 7(b)). In the following, the direction of the center between the direct field of view A (optical axis X) and the reflected field of view B (reflective axis Y) in plan view (the direction shown by the dashed line in Figure 7(a)) will be referred to as the "line of sight direction". In the example shown in Figure 7(a), the line of sight direction is the direction that bisects the first passage 2a and the second passage 2b in plan view (a direction inclined at approximately 45° with respect to each passage).

[0092] Figure 8 shows an example where the camera support 240 is rotated clockwise in a plan view. An operator adjusting the orientation of the camera support 240 can rotate the camera support 240 around the adjustment shaft 232a by rotating the worm shaft 242b of the camera support 240. The example shown in the figure illustrates a case where the camera support 240 is rotated approximately 10° clockwise in a plan view.

[0093] As shown in Figure 8(a), as the camera support 240 rotates, the direct field of view A (optical axis X) of the camera 100 is also displaced clockwise in a plan view. In addition, as the direct field of view A (optical axis X) is displaced, the reflected field of view B (reflection axis Y) of the camera 100 is displaced counterclockwise in a plan view. In this case, the direct field of view A and the reflected field of view B are displaced in directions that bring them closer together. In the above example, the angle α formed by the optical axis X and the reflection axis Y in a plan view is approximately 70° (see Figure 8(b)). Note that in the camera support mechanism 200, even if the direction of each field of view is changed, the line of sight direction (the direction indicated by the dashed arrow in Figures 7(a) and 8(a)) remains unchanged from before the change.

[0094] As shown in Figures 7(a) and 8(a), by changing the direction of each field of view of the camera 100 as described above, the blind spots in each field of view can be reduced. Note that the above-described method of changing the direction of each field of view is just one example. The direction of each field of view can be changed as appropriate from the viewpoint of suitably photographing the subject.

[0095] As described above, the camera support mechanism 200 according to one embodiment of the present invention is A camera support mechanism 200 that supports a camera 100 capable of photographing a passageway 2 (the object to be photographed), A mirror portion 260 is formed to allow light in a first direction along the optical axis X of the lens 110 of the camera 100 to pass through to the lens 110, and to reflect light in a second direction different from the first direction back to the lens 110, A first liquid crystal shutter 280 (first opening / closing part) allows light in the first direction to pass towards the mirror part 260 when open, and blocks light in the first direction when closed, A second liquid crystal shutter 290 (second opening / closing part) allows light from the second direction to pass through to the mirror part 260 when open, and blocks light from the second direction when closed, It is equipped with, The device is configured to allow switching between a state in which the first liquid crystal shutter 280 is open and the second liquid crystal shutter 290 is closed, and a state in which the first liquid crystal shutter 280 is closed and the second liquid crystal shutter 290 is open.

[0096] This configuration allows for shooting in multiple directions without narrowing the field of view. Specifically, the camera 100 can shoot in a first direction using light that has passed through the first liquid crystal shutter 280 and transmitted through the mirror section 260. Furthermore, the camera 100 can shoot in a second direction using light that has passed through the second liquid crystal shutter 290 and reflected by the mirror section 260. With the above configuration, it is possible to shoot using approximately the entire field of view of the camera 100 in both directions (direct field of view A and reflected field of view B). Therefore, shooting can be performed without narrowing the field of view in each direction.

[0097] Furthermore, the first liquid crystal shutter 280 and the second liquid crystal shutter 290 are It is formed by a liquid crystal shutter.

[0098] This configuration allows for quick switching between light transmission and blocking in the first liquid crystal shutter 280 and the second liquid crystal shutter 290.

[0099] Furthermore, the camera support mechanism 200 is The system comprises a camera support section 240 and a mirror support section 250 (first support section) that rotatably support the camera 100 around an adjustment axis 232a (first rotation axis) that is perpendicular to the optical axis X, The camera support portion 240 and the mirror support portion 250 are, The rotational position of the camera 100 around the adjustment shaft 232a can be adjusted so as to change the angle between the direct field of view A (first field of view) based on light transmitted through the mirror portion 260 and the reflected field of view B (second field of view) based on light reflected by the mirror portion 260, when viewed in the axial direction of the adjustment shaft 232a.

[0100] This configuration allows the direction of the direct field of view A and the reflected field of view B of camera 100 to be changed, thereby reducing blind spots in each field of view.

[0101] Furthermore, the camera support mechanism 200 is The device includes a tilt arm 230 (second support part) that supports the camera support part 240 and the mirror support part 250, and is formed to be rotatable about a tilt axis 222a (second pivot axis) that is perpendicular to the adjustment axis 232a.

[0102] This configuration allows the orientation (vertical direction) of the camera 100 to be adjusted around the tilt axis 222a.

[0103] Furthermore, the camera support mechanism 200 is The system includes a pan arm 220 (third support part) that supports the tilt arm 230 and is rotatable about a pan axis 211 (third pivot axis) perpendicular to the tilt axis 222a.

[0104] This configuration allows for adjustment of the orientation (horizontal orientation) of the camera 100 around the pan axis 211.

[0105] Furthermore, the video acquisition system 1 according to one embodiment of the present invention is A camera support mechanism 200 according to one embodiment of the present invention, The aforementioned camera 100, The first liquid crystal shutter 280 and the second liquid crystal shutter 290 are operated to allow light from the first direction to pass through and block light from the second direction, and an image acquisition means 300 acquires an image of the camera 100 based on the light transmitted through the mirror section 260, and the first liquid crystal shutter 280 and the second liquid crystal shutter 290 are operated to block light from the first direction and allow light from the second direction to pass through, and an image acquisition means 300 acquires an image of the camera 100 based on the light reflected by the mirror section 260, It is equipped with the following features.

[0106] This configuration allows for shooting in multiple directions without narrowing the field of view.

[0107] In this embodiment, passageway 2 is one form of the object to be photographed according to the present invention. Furthermore, the first liquid crystal shutter 280 according to this embodiment is one form of the first opening / closing unit according to the present invention. Furthermore, the second liquid crystal shutter 290 according to this embodiment is one form of the second opening / closing part according to the present invention. Furthermore, the adjustment shaft 232a according to this embodiment is one form of the first rotational shaft according to the present invention. Furthermore, the camera support portion 240 and the mirror support portion 250 according to this embodiment are one form of the first support portion according to the present invention. Furthermore, the tilt axis 222a according to this embodiment is one form of the second pivot axis according to the present invention. Furthermore, the tilt arm 230 according to this embodiment is one form of the second support part according to the present invention. Furthermore, the pan shaft 211 according to this embodiment is one form of the third rotational shaft according to the present invention. Furthermore, the pan arm 220 according to this embodiment is one form of the third support part according to the present invention. Furthermore, the direct field of view A according to this embodiment is one form of the first field of view according to the present invention. Furthermore, the reflected field of view B according to this embodiment is one form of the second field of view according to the present invention.

[0108] Although embodiments of the present invention have been described above, the present invention is not limited to the above configuration, and various modifications are possible within the scope of the invention as described in the claims.

[0109] For example, the camera support mechanism 200 according to this embodiment may be provided with markings (such as scales or templates) that serve as a guide for angle adjustment by rotation around each axis (pan axis 211, tilt axis 222a, and adjustment axis 232a). With the above configuration, it becomes easy to adjust the rotational position of each member around each axis.

[0110] Furthermore, in the camera support mechanism 200 according to this embodiment, an example has been shown in which the vertical and horizontal orientation of the camera 100 can be adjusted around the pan axis 211 and the tilt axis 222a, but the invention is not limited to the example described above. For example, the camera support mechanism 200 can also be configured so that one or both of the above axes cannot be adjusted.

[0111] Furthermore, in the camera support mechanism 200 according to this embodiment, an example was shown in which the camera support part 240 is rotated relative to the mirror support part 250 by the field of view adjustment part 242, but the invention is not limited to the example described above. For example, a configuration in which the mirror support part 250 is rotated relative to the camera support part 240 can also be adopted.

[0112] Furthermore, in the camera support mechanism 200 according to this embodiment, the angle between the direct field of view A and the reflected field of view B can be adjusted by the field of view adjustment unit 242, but it is also possible to make the above angle not adjustable.

[0113] Furthermore, in the camera support mechanism 200 according to this embodiment, an example is shown in which the first opening / closing part and the second opening / closing part are formed by liquid crystal shutters, but the invention is not limited to the example described above. For example, it is also possible to use mechanical shutters as each opening / closing part.

[0114] Furthermore, although the camera support mechanism 200 according to this embodiment is shown as having two shooting directions, it is not limited to the above example. For example, the camera support mechanism 200 can be configured to shoot in three or more directions. In this case, for example, a configuration can be adopted in which a mirror having both light-transmitting and reflective properties similar to the mirror section 260 is added. As an example of the above configuration, if a mirror symmetrical to the mirror section 260 is placed within the field of view of the camera 100, it is possible to shoot not only to the right but also to the left. In this case, a shutter or an opening in the housing 270 can be appropriately added to allow light from the left to enter the mirror.

[0115] Furthermore, although this embodiment shows an example of applying the video acquisition system 1 to a facility for the elderly, it is not limited to the example described above. The video acquisition system 1 can be applied to various facilities (buildings). [Explanation of Symbols]

[0116] 1. Video acquisition system 100 Cameras 200 Camera support mechanism 300 Video acquisition method

Claims

1. A camera support mechanism that supports a camera capable of photographing a subject, A mirror portion is formed to allow light in a first direction along the optical axis of the camera lens to pass through to the lens side, and to reflect light in a second direction different from the first direction back to the lens side. A first opening / closing section that, when open, allows light in the first direction to pass towards the mirror section, and when closed, blocks light in the first direction, A second opening / closing section that, when open, allows light from the second direction to pass towards the mirror section, and when closed, blocks light from the second direction. It is equipped with, The device is configured to allow switching between a state in which the first opening / closing section is open and the second opening / closing section is closed, and a state in which the first opening / closing section is closed and the second opening / closing section is open. Camera support mechanism.

2. The first opening / closing section and the second opening / closing section are, Formed by a liquid crystal shutter, The camera support mechanism according to claim 1.

3. The system includes a first support portion that rotatably supports the camera about a first pivot axis perpendicular to the optical axis, The first support portion is, The rotational position of the camera around the first rotation axis can be adjusted so as to change the angle between the first field of view, which is based on light transmitted through the mirror, and the second field of view, which is based on light reflected from the mirror, when viewed in the axial direction of the first rotation axis. The camera support mechanism according to claim 1.

4. The system comprises a second support portion that supports the first support portion and is rotatable about a second pivot axis perpendicular to the first pivot axis, The camera support mechanism according to claim 3.

5. The system includes a third support portion that supports the second support portion and is rotatable about a third pivot axis perpendicular to the second pivot axis. The camera support mechanism according to claim 4.

6. A camera support mechanism according to any one of claims 1 to 5, The aforementioned camera, An image acquisition means that acquires an image of the camera based on the light transmitted through the mirror while operating the first opening / closing part and the second opening / closing part to allow light in the first direction to pass through and block light in the second direction, and acquires an image of the camera based on the light reflected by the mirror while operating the first opening / closing part and the second opening / closing part to block light in the first direction and allow light in the second direction to pass through, A video acquisition system equipped with the following features.

Images