JP2024074695A - Cameras, Trains, and Surveillance Systems - Google Patents

Abstract

[Problem] To realize a vehicle-side camera that can simplify the wiring and other equipment required when installing multiple vehicle-side cameras on a vehicle. [Solution] The camera (C11) is a binocular camera that captures images of subjects getting on and off through multiple doors (101-106, 201-206) equipped on a train (1), and includes a first camera (11N) having a first optical axis (AX1) and a first focal length, and a second camera (11D) having a second optical axis (AX2) that is not parallel to the first optical axis and a second focal length that is longer than the first focal length. [Selected Figure] Figure 1

Description

One aspect of the present invention relates to a camera, etc.

Patent document 1 discloses a surveillance system that displays door camera images captured by a door camera installed near the vehicle door on a monitor in the driver's cab.

JP 2019-92136 A

In the technology described in Patent Document 1, door cameras are installed on the left and right exterior wall surfaces of each car that makes up the train, and video data captured by each of the multiple door cameras is transmitted to a monitor. This requires the installation of door cameras on the exterior wall of each car in accordance with the number of door cameras installed on the train. In addition, forming a network that includes a transmission device that connects each of the multiple door cameras to the monitor and various electrical wiring makes the wiring structure inside the car complex.

A camera installed on the exterior wall of a vehicle is called a vehicle side camera (vehicle-side camera). The present invention aims to realize a vehicle-side camera that can simplify the wiring and other equipment required when installing multiple vehicle-side cameras in a vehicle.

To solve the above problems, a camera according to one aspect of the present invention is a binocular camera that captures images of subjects getting on and off through multiple doors on a train, and includes a first camera having a first optical axis and a first focal length, and a second camera having a second optical axis that is not parallel to the first optical axis and a second focal length that is longer than the first focal length.

A train according to one aspect of the present invention is a train provided with multiple doors for boarding and alighting, and includes a first camera and a second camera provided on the side of a first end of the train, facing toward a second end of the train, and capturing images of subjects boarding and alighting through at least some of the multiple doors, the first camera having a first optical axis and a first focal length, the second camera having a second optical axis and a second focal length longer than the first focal length, and an angle between the second optical axis and the horizontal direction smaller than an angle between the first optical axis and the horizontal direction.

A monitoring system according to one aspect of the present invention is a monitoring system for a train equipped with multiple doors for boarding and alighting, the train having multiple cars, and including a first camera and a second camera provided on the side of a first end of the car, facing toward a second end of the car, capturing images of subjects boarding and alighting through at least some of the multiple doors, and a display device that displays images represented by the imaging data of the first camera and the second camera, respectively, the first camera having a first optical axis and a first focal length, the second camera having a second optical axis and a second focal length longer than the first focal length, and an angle between the second optical axis and the horizontal direction smaller than an angle between the first optical axis and the horizontal direction.

According to one aspect of the present invention, it is possible to simplify the wiring and other equipment required when installing multiple vehicle-side cameras in a vehicle.

FIG. 1 is a schematic diagram illustrating an external configuration of a train according to a first embodiment of the present invention. 1 is a perspective view showing an external configuration of a camera according to a first embodiment of the present invention. 1 is a front view showing the external configuration of a camera according to a first embodiment of the present invention. FIG. 2 is a bottom view showing the external configuration of the camera according to the first embodiment of the present invention. 1 is a perspective view showing an example of the internal configuration of a camera according to a first embodiment of the present invention. FIG. 1 is a plan view showing an example of the internal configuration of a camera according to a first embodiment of the present invention. 3A and 3B are schematic diagrams for explaining the imaging fields of a first camera and a second camera included in the camera according to the first embodiment of the present invention. FIG. 11 is a side view showing a schematic external configuration of a train according to a second embodiment of the present invention. FIG. 11 is a functional block diagram showing a configuration of a monitoring system according to a third embodiment of the present invention. FIG. 4 is a diagram showing an example of a display screen of a monitor.

[Embodiment 1]
An embodiment of the present invention will be described below with reference to the drawings. However, the following description is for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified. Each figure referred to in the following description shows only the main members necessary for explaining the embodiment in a simplified manner for convenience of explanation, and the explanation of known technical matters is appropriately omitted for brevity. Therefore, the camera etc. in this embodiment may optionally include known components not shown in each referenced figure. In addition, the shapes and dimensions of the members in each figure do not necessarily reflect the actual shapes and dimensions, and are appropriately changed for clarity and simplification of the drawings.

In this embodiment, for example, a vehicle-side camera is described that is installed on the side (external wall surface of the vehicle body) of multiple railway cars that make up a train operated on a regular railway. In the following description, the railway car may be abbreviated simply to the vehicle, and the vehicle-side camera may be abbreviated simply to the camera. The camera and surveillance system in this embodiment may also be appropriately applied to vehicles other than railway cars. For example, it may be applied to vehicles such as streetcars and railless trains (trolleybuses). It may also be applied to vehicles such as articulated buses.

In the following explanation, we will first provide an overview of the train on which the camera in this embodiment is installed and its advantages, and then provide specific examples of the camera.

<Train Overview>
Fig. 1 is a schematic diagram showing an external configuration of a train 1 according to the present embodiment. The diagram indicated by reference numeral 1001 in Fig. 1 is a plan view showing the configuration of the train 1, and the diagram indicated by reference numeral 1002 in Fig. 1 is a side view showing the configuration of the train 1.

As shown in FIG. 1, the train 1 in this embodiment is a two-car train consisting of a first car V1 and a second car V2, and the first car V1 and the second car V2 are connected to each other via a coupling section 30. The specific structure of the coupling section 30 is not particularly limited, and a known structure can be applied. In addition, the train 1 is not limited to a two-car train, and may be a three-car or four-car train. The train 1 may be connected to five or more cars. For example, when the train 1 is a train of three or more cars, the first car V1 may be the front or rear car in the train, or may be an intermediate car located between the front and rear cars. The first car V1 may be a trailer car with power or a trailer car without power. The second car V2 may be a car located in front of or behind the first car V1 and adjacent to the first car V1. With reference to the following explanation, it is easy to understand that the cameras described below can be installed at appropriate intervals depending on the number of cars included in train 1, and that the same effects as the respective embodiments described below can be achieved even in a configuration in which multiple cameras are installed (in other words, a train having multiple first cars V1).

In the example shown in FIG. 1, the first car V1 is the leading car located on the side of the train 1 in the direction of travel D1. The train 1 is stopped in the station premises, and the platform PF is located on the left side of the train 1 in the direction of travel D1. In the following, the side of the first car V1 and the second car V2 of the train 1 in the direction of travel D1 may be referred to as the front side, and the opposite side as the rear side. One end of each car extending longitudinally along the direction of travel D1 is referred to as the first end E1, and the opposite end is referred to as the second end E2. In FIG. 1, for clarity of illustration, reference symbols are shown for the first end E1 located on the front side of the first car V1 and the second end E2 located on the rear side of the second car V2.

The first vehicle V1 has three doors 101, 102, 103 in sequence from front to rear on one side, and three doors 104, 105, 106 in sequence from front to rear on the other side. The first vehicle V1 may have a monitor (display device) 120 installed, for example, on the front side of the interior of the vehicle, and the monitor 120 may be installed in the driver's seat (not shown).

In the train 1 of this embodiment, the first car V1 and the second car V2 may have the same or substantially the same structure. In other words, the second car V2 may be a car obtained by inverting the first car V1. The second car V2 has doors 201, 202, and 203, which may correspond to the doors 101, 102, and 103 of the first car V1, respectively. The second car V2 also has doors 204, 205, and 206, which may correspond to the doors 104, 105, and 106 of the first car V1, respectively. The second car V2 may have a monitor 220 on the rear side, which may correspond to the monitor 120 of the first car V1. In the following description, the description of the first car V1 is the same for the second car V2 unless otherwise specified. Therefore, a detailed description of the second car V2 is omitted.

In recent years, there has been a demand for door cameras to be used to check whether passengers are getting on and off trains 1 that run on local routes, etc. (in other words, to check safety). This is because on local routes, trains 1 are often one-man trains, meaning that trains 1 often have only one crew member.

The direction of travel of train 1 may be reversed, and the position of platform PF changes depending on the shape of the station. Also, typically, displaying on the monitor images captured with an imaging field of view oriented to look behind the direction of travel is less likely to cause discomfort to the vehicle driver. For this reason, for example, it is envisaged that door cameras will be installed on the front left and right side surfaces and rear left and right side surfaces of first vehicle V1, i.e., at each of the four corners in a plan view of first vehicle V1.

However, for example, if door cameras are installed at the four corners of each of the first vehicle V1 and the second vehicle V2, a total of eight door cameras must be attached to the exterior walls of the vehicles and electrical wiring must be installed to each door camera. Furthermore, it is necessary to run a network cable from the door camera installed in the second vehicle V2 to the monitor 120 of the first vehicle V1, and to connect the vehicles with a cable at the connection part 30, for example using a jumper wire.

The inventors conducted extensive research and came up with the present invention by focusing on the above-mentioned new problem. In the train 1 of this embodiment, a camera C11 is provided on one side of the first end E1, and a camera C12 is provided on the other side. Cameras C11 and C12 are car-side cameras that capture images of the door and its surroundings from outside the car. In the example shown in FIG. 1, camera C11 is provided on the side of the left side (platform PF side) facing the traveling direction D1, facing the second end E2 of the train 1. Camera C11 may be located, for example, above the crew door (not shown).

In the following explanation, the explanation of camera C11 also applies to camera C12 unless otherwise specified. Therefore, a repeated explanation of camera C12 will be omitted. In addition, cameras C21 and C22 are provided on the second vehicle V2, which may correspond to cameras C11 and C12 of the first vehicle V1, respectively. Therefore, a repeated explanation of cameras C21 and C22 will be omitted.

Camera C11 is equipped with a first camera 11N and a second camera 11D used to capture images relatively farther away than the first camera 11N. Camera C11 captures images of subjects getting on and off through multiple doors (doors 101-103, doors 204-206) on train 1. Camera C11 is a so-called binocular camera in which first camera 11N and second camera 11D are housed in a single housing 5. The subjects may be people or various movable objects. In FIG. 1, passengers P1 and P2 are shown as examples of subjects to be captured, but examples of the objects include animals (e.g., assistance dogs) or autonomous or remotely controlled mobile machines (e.g., transport robots).

The first camera 11N has a first optical axis and a first focal length, and the second camera 11D has a second optical axis that is not parallel to the first optical axis and a second focal length that is longer than the first focal length. Camera C11 differs from a stereo camera, which is a type of binocular camera, in that the optical axes of the first camera 11N and the second camera 11D intersect with each other.

The orientations of the first and second optical axes correspond to the orientations of the lenses in the first camera 11N and the second camera 11D, respectively. The focal lengths of the first and second cameras 11N and 11D correspond to the lens configurations of the respective cameras. In general, the longer the focal length, the narrower the angle of view.

The first camera 11N and the second camera 11D can capture an image at a predetermined frame rate within a field of view determined by the installation angle and lens configuration within the housing 5. The field of view of the first camera 11N includes the multiple doors (doors 101, 102, 103) of the first vehicle V1 located on the side of the train 1 where the camera C11 is installed, and their surroundings. The field of view of the second camera 11D includes the multiple doors (doors 206, 205, 204) of the second vehicle V2 located on the side of the train 1 where the camera C11 is installed, and their surroundings.

In FIG. 1, the viewing area A1 included in the field of view of the first camera 11N is shown by a long chain line. This viewing area A1 is a schematic area, but for example, the very end of the viewing area A1 may correspond to the far end of the range of the depth of field of the first camera 11N. The viewing area A1 includes a first monitoring area, which is an area where it is necessary to check whether or not a passenger P1 is near the first vehicle V1 for safety confirmation, etc. Such a first monitoring area is virtually shown by diagonal hatching slanting upwards to the right in the diagram indicated by the reference numeral 1002 in FIG. 1.

In addition, in FIG. 1, the viewing area A2 included in the imaging field of the second camera 11D is shown by a dashed line. This viewing area A2 is a schematic area, but for example, the very end of the viewing area A2 may correspond to the far end of the range of the depth of field of the second camera 11D. The viewing area A2 includes a second monitoring area, which is an area where it is necessary to check whether or not a passenger P2 is near the second vehicle V2 for safety confirmation, etc. Such a second monitoring area is virtually shown by left-upward diagonal hatching in the diagram indicated by the reference numeral 1002 in FIG. 1.

A transmission device 110 may be provided in the first vehicle V1, and the cameras C11 and C12 may be connected to the monitor 120 via a network cable or the like via the transmission device 110.

According to the above configuration, the first camera 11N, which has a relatively short focal length, can capture an image of the viewing area A1, which is close to the installation position of the camera C11, and the second camera 11D, which has a relatively long focal length, can capture an image of the viewing area A2, which is far from the installation position of the camera C11. The angle of view of the second camera 11D is narrower than the angle of view of the first camera 11N, but because the first optical axis and the second optical axis are not parallel, it is possible to fit the desired imaging range within the angle of view of the second camera 11D.

By installing one camera C11 equipped with a first camera 11N and a second camera 11D in the first car V1, wiring and other equipment can be simplified compared to installing car-side cameras (door cameras) at separate locations on each car of the train 1. This allows for a reduction in the amount of electrical wiring and electronic equipment used. And by reducing the construction work required to install the car-side cameras, cost savings can be achieved. Furthermore, in the train 1, it is not necessary to transmit video data from the door camera of the second car V2 to the monitor 120. As a result, the first car V1 and the second car V2 may form separate networks. Therefore, the wiring structure inside the first car V1 can be effectively simplified.

Note that train 1 does not have to be equipped with cameras C21 and C22. The traveling direction D1 of train 1 may be fixed in a predetermined direction. Also, train 1 may travel in the opposite direction to traveling direction D1, i.e., second car V2 may be the leading car. In this case, a network may be formed so that images from cameras C11 and C12 can be displayed on monitor 220. In other words, images captured with an imaging field of view oriented to check the front side relative to the traveling direction may be displayed on the monitor. This can further reduce the number of cameras installed.

<Camera>
An example of a specific configuration of the camera C11 in this embodiment will be described below with reference to Figures 2 to 6. Figure 2 is a perspective view showing the external configuration of the camera C11 in this embodiment. Figure 3 is a front view showing the external configuration of the camera C11. Figure 4 is a bottom view showing the external configuration of the camera C11. Figure 4 shows the state before the camera C11 is attached to the first vehicle V1. Figure 5 is a perspective view showing an example of the internal configuration of the camera C11. Figure 6 is a plan view showing an example of the internal configuration of the camera C11. Figures 5 and 6 show a state in which a part of the housing (a lid portion) has been removed.

As shown in Figures 2 to 6, the camera C11 can be installed, for example, on the outer wall W1 that constitutes the side surface of the first vehicle V1. The camera C11 has a housing 5, and the housing 5 can house the first camera 11N and the second camera 11D watertight therein. The housing 5 includes, for example, a board 60 to which the first camera 11N and the second camera 11D are fixed, and a lid portion 70 that covers one surface 60A of the board 60 and has a shape that forms an internal space of the housing 5. In the camera C11 of this embodiment, the first camera 11N and the second camera 11D may be camera modules fixed to the board 60.

The lid portion 70 may have a lid body portion 71 and a window portion 75. The lid body portion 71 has a flange portion 72, and the camera C11 may be fixed to the outer wall W1 by screws or the like using the flange portion 72. The lid body portion 71 may have a shape in which the flange portion 72 is located near the outer edge of the board 60 (excluding the front portion where the window portion 75 is attached) when the lid portion 70 and the board 60 are combined.

The window portion 75 has an optical window 76 and a frame portion 77 that surrounds and holds the outer edge of the optical window 76. The window portion 75 is located on the front side of the camera C11 so that both the first optical axis AX1 of the first camera 11N and the second optical axis AX2 of the second camera 11D pass through one optical window 76. The optical window 76 is solid and not hollow, and is formed from a light-transmitting material. Examples of light-transmitting materials include glass and resin. The frame portion 77 is used to fix the window portion 75 to the lid main body portion 71 with screws or the like to form the lid portion 70. The lid portion 70 may have a packing (not shown) between the lid main body portion 71 and the window portion 75.

The surface 60A of the substrate 60 may be provided with mounting portions for mounting the first camera 11N and the second camera 11D. In the example shown in Figs. 5 and 6, the surface 60A of the substrate 60 is provided with a plurality of bosses (protruding portions) having a protruding shape as mounting portions. The substrate 60 has (i) four bosses 61 used to fix the first camera 11N, and (ii) four bosses 62 used to fix the second camera 11D, formed on the surface 60A. The bosses 61 and 62 have screw holes.

The first camera 11N includes a lens unit 81 and a base unit 89. The lens unit 81 may be attached to the base unit 89. A first element unit, for example, may be provided inside the base unit 89. The first element unit includes, for example, a sensor board, a memory board, and an encoder board. The sensor board and the memory board may be electrically connected to each other by a connector, and the memory board and the encoder board may be electrically connected to each other by another connector.

Known parts can be used for the lens unit 81 and the first element unit, and the specific structure is not particularly limited. Explained generally, the lens unit 81 has a first optical axis AX1 and a first focal length, and is, for example, a single-focus lens including a lens group made up of multiple lenses. The first focal length can be adjusted by the lens configuration of the lens unit 81.

The sensor board may be a circuit board including an image sensor, for example, a CMOS (Complementary Metal Oxide Semiconductor) sensor. The memory board may include, for example, an FPGA (Field Programmable Gate Array), and a circuit including a memory (storage element) may be configured by the FPGA. The memory board stores image data output as a digital signal from the sensor board. A first cable (not shown) is connected to the encoder board, and the first cable is connected to a transmission device 110 (see FIG. 1). The encoder board encodes the image data acquired from the memory board into a predetermined data format and outputs it to the transmission device 110 (see FIG. 1) using the first cable. The first cable may include a power supply cable and a communication cable, and the specific configuration is not particularly limited.

The base portion 89 has four mounting portions 89X that correspond to the four bosses 61 of the substrate 60. The mounting portions 89X have holes 89H through which screws are inserted. The first camera 11N can be fixed to the substrate 60 by aligning the holes of the mounting portions 89X with the screw holes of the bosses 61 and screwing them in place.

5 and 6, the hole 89H of the mounting part 89X1, which is one of the four mounting parts 89X, is circular, and the holes 89H of the other three mounting parts 89X2 are shaped with a long axis. More specifically, the hole 89H of the mounting part 89X2 has a hole shape with a play (position adjustment area) such that the mounting part 89X2 and the boss 61 can be screwed even if the base part 89 is rotated slightly around the mounting part 89X1 as the center of rotation. This allows the mounting angle of the base part 89 to the board 60 (i.e., the mounting angle of the first camera 11N) to be adjusted to a certain extent. The mounting part 89X1 may be, for example, the mounting part 89X located on the side closer to the optical window 76 and closer to the second camera 11D among the four mounting parts 89X.

The second camera 11D includes a lens unit 91 and a base unit 99. The lens unit 91 may be attached to the base unit 99. For example, a second element unit may be provided inside the base unit 99. The second element unit includes, for example, a sensor board, a memory board, and an encoder board. The lens unit 91 and the second element unit in the second camera 11D can be understood by referring to the description of the lens unit 81 and the first element unit of the first camera 11N described above. The lens unit 91 has a second optical axis AX2 and a second focal length, and may be, for example, a single focus lens. The lens unit 91 has a lens configuration having the second focal length that is longer than the first focal length of the lens unit 81. A second cable (not shown) is connected to the encoder board in the second element unit, and the second cable is connected to the transmission device 110 (see FIG. 1). The second cable may include a power supply cable and a communication cable, and the specific configuration is not particularly limited.

The base portion 99 has four mounting portions 99X that correspond to the four bosses 62 of the substrate 60. The mounting portions 99X have holes through which screws can be inserted, and the second camera 11D can be fixed to the substrate 60 by aligning the holes of the mounting portions 89X with the screw holes of the bosses 62 and screwing them in place.

The second optical axis AX2 may be perpendicular or approximately perpendicular to the surface of the optical window 76. The first camera 11N may be installed at an angle with respect to the surface of the optical window 76, and the first optical axis AX1 is inclined with respect to the surface of the optical window 76. The angle at which the first optical axis AX1 of the first camera 11N and the second optical axis AX2 of the second camera 11D intersect with each other is referred to as θ0. The angle θ0 is an acute angle. The angle θ0 may be, for example, 10° or more and 45° or less, or 10° or more and 20° or less.

As described above, in the present embodiment, the camera C11 is capable of adjusting the fixed position of the first camera 11N on the substrate 60. This allows the angle θ0 of the first optical axis AX1 relative to the second optical axis AX2 to be adjusted. This allows the range that can be imaged by the first camera 11N to be easily adjusted. In addition, the range that can be imaged by the second camera 11D may be adjusted by the installation angle of the camera C11 relative to the outer wall W1.

The first camera 11N and the second camera 11D may each be attached perpendicular to the substrate 60, or may be attached at a slight inclination to the substrate 60. The first camera 11N and the second camera 11D may each be attached to the substrate 60 so that the lens portion 81 and the lens portion 91 are each inclined away from the substrate 60.

The angle of inclination of the first optical axis AX1 of the first camera 11N relative to the substrate 60 is referred to as the first inclination angle, and the angle of inclination of the second optical axis AX2 of the second camera 11D relative to the substrate 60 is referred to as the second inclination angle. The first and second inclination angles refer to the elevation angles when the substrate 60 is regarded as a horizontal plane. Note that, when the camera C11 is attached to the first vehicle V1, the inclination relative to the substrate 60 corresponds to the inclination relative to the outer wall W1. The first inclination angle may be larger than the second inclination angle, which allows the imaging range of the camera C11 around the doors (doors 101 to 103) of the first vehicle V1 to be wider. For example, the first inclination angle may be 5°, and the second inclination angle may be 2°.

When the camera C11 is attached to the first vehicle V1, the first camera 11N may be located higher in the vertical direction (height direction) of the first vehicle V1 than the second camera 11D. This makes it easier to accommodate the first camera 11N and the second camera 11D in a relatively small space within the housing 5.

The camera C11 may include a hole 68 that penetrates from the front surface 60A to the rear surface 60B of the substrate 60. The number of holes 68 may be one or more. The first cable and the second cable may be inserted through the hole 68 and drawn out to the outside of the housing 5. The hole 68 may be provided with, for example, a bushing.

A packing P may be provided on the peripheral portion of the surface 60A of the substrate 60, and the watertightness of the housing 5 can be improved by attaching the cover 70 and the substrate 60 via the packing P. An intermediate member 40 (see FIG. 3) may be interposed between the camera C11 and the outer wall W1. The intermediate member 40 may be, for example, a metal plate having passages for the first cable and the second cable.

(Example of camera imaging field of view)
FIG. 7 is a schematic diagram for explaining the imaging field of the first camera 11N and the second camera 11D equipped in the camera C11 of this embodiment. As shown in the diagram indicated by the reference numeral 7001 in FIG. 7, the angle of view of the first camera 11N is referred to as θ1. The focal length of the first camera 11N and the angle of view θ1 are related to each other. The focal length of the first camera 11N may be set so that the depth of field includes the rear side (rear side) of the long side S12 on the rear side of the rectangular opening surface of the rearmost door 103 of the first vehicle V1. The mounting angle and the angle of view θ1 of the first camera 11N with respect to the first vehicle V1 may be set so that the imaging field of the first camera 11N includes the area above the height position H1 of the doors (doors 101 to 103) of the first vehicle V1 and includes the near side (forward side) of the long side S11 on the front side of the rectangular opening surface of the frontmost door 101 of the first vehicle V1. In the example shown in FIG. 7, the angle of view θ1 is 58°.

As shown in the diagram indicated by the reference numeral 7002 in FIG. 7, the angle of view of the second camera 11D is referred to as θ2. The focal length of the second camera 11D is related to the angle of view θ2. The focal length of the second camera 11D may be set so that the depth of field includes the rear side (rear side) of the rear long side S22 of the rectangular opening surface of the rearmost door 204 of the second vehicle V2, and the front side (forward side) of the front long side S21 of the rectangular opening surface of the frontmost door 206 of the second vehicle V2. The mounting angle of the second camera 11D to the first vehicle V1 and the angle of view θ2 may be set so that the imaging field of the second camera 11D includes the area above the height position H2 of the doors (doors 204 to 206) of the second vehicle V2 and includes the front side (forward side) of the long side S21. In the example shown in FIG. 7, the angle of view θ2 is 10.5°.

By installing the first camera 11N and the second camera 11D on the first vehicle V1 as described above, the effects of the camera C11 described above can be achieved. Therefore, in another embodiment, the first camera 11N and the second camera 11D do not have to be housed in a single housing 5, and this will be described in detail later as embodiment 2.

(Other configurations)
(a) The number of doors provided in each car (e.g., the first car V1 and the second car V2) of the train 1 is not particularly limited.

(b) The first cable and the second cable may be aggregated into a single cable within the housing 5, or may be physically bundled together and inserted into the hole 68.

(c) The mounting angle of not only the first camera 11N but also the second camera 11D relative to the substrate 60 may be adjustable.

(d) The first camera 11N and the second camera 11D may have zoom lenses as the lens unit 81 and the lens unit 91, respectively, in which case "having a second focal length longer than the first focal length" means that the second focal length of the second camera 11D is adjustable so that it is longer than the first focal length of the first camera 11N.

[Embodiment 2]
Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals are given to members having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

Figure 8 is a side view that shows a schematic external configuration of the train 1 in the second embodiment. As shown in Figure 8, the train 1 in this embodiment differs from the first embodiment in that the first camera 11N and the second camera 11D are not housed in a single housing 5.

That is, the train 1 is provided with a first camera 11N and a second camera 11D that are provided on the side at the first end E1, face the second end E2 of the train 1, and capture images of subjects getting on and off through at least some of the multiple doors. The first camera 11N has a first optical axis AX1 and a first focal length, and the second camera 11D has a second optical axis AX2 and a second focal length that is longer than the first focal length. The angle θ20 between the second optical axis AX2 and the horizontal direction is smaller than the angle θ10 between the first optical axis AX1 and the horizontal direction. In FIG. 8, the direction of the line corresponding to the surface of the platform PF in a side view is considered to be the horizontal direction.

According to the above configuration, the first camera 11N, which has a relatively short focal length, can capture an image of an area close to the first end E1 of the train 1, and the second camera 11D, which has a relatively long focal length, can capture an image of an area far from the first end E1. The angle of view of the second camera 11D is narrower than that of the first camera 11N, but by making the angle θ20 between the second optical axis AX2 and the horizontal direction smaller than the angle θ10 between the first optical axis AX1 and the horizontal direction, it is possible to fit the desired imaging range within the angle of view of the second camera 11D.

In this embodiment, the first camera 11N and the second camera 11D may be imaging devices (cameras) each having an individual housing. The first camera 11N and the second camera 11D may be adjacent to each other so as to face the same side, either the front or the rear, with respect to the traveling direction D1 of the train 1, and may be installed in an arrangement in which the first optical axis AX1 and the second optical axis AX2 intersect. By installing such a first camera 11N and a second camera 11D at the first end E1 of the train 1, it is possible to reduce the equipment such as wiring required for installing the first camera 11N and the second camera 11D compared to the case of installing multiple cameras at separate locations on the train 1.

In this embodiment, the train 1 includes a first car V1 and a second car V2, each of which has at least one door. The first camera 11N and the second camera 11D are provided in the first car V1, and the second camera 11D captures images of subjects getting on and off through a door provided in the second car V2.

The above configuration makes it possible to reduce the amount of wiring and other equipment required to install the cameras compared to when the first camera 11N is installed on the first vehicle V1 and the second camera 11D is installed on the second vehicle V2.

[Embodiment 3]
Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals are given to members having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

The monitoring system 300 according to this embodiment will be described with reference to FIG. 9 and FIG. 10. FIG. 9 is a functional block diagram showing the configuration of the monitoring system 300. As shown in FIG. 9, the monitoring system (display system) 300 includes a monitor 120, a display control device 310, a storage unit 320, and a camera C. Here, the cameras C11 and C12 provided in the first vehicle V1 are collectively referred to as cameras C. The monitoring system 300 may also include a transmission device 110 (see FIG. 1). The transmission device 110 is not shown in FIG. 9. Note that the following description may also be applied to a monitoring system including cameras C21, C22, and a monitor 220 in the second vehicle V2.

The monitor 120 is a display device equipped with a display screen, such as a liquid crystal display device. The type of display device is not particularly limited. The monitor 120 displays the image captured by the camera C. The cameras C are each equipped with a first camera 11N and a second camera 11D, and the monitor 120 displays the images shown by the image data of the first camera 11N and the second camera 11D, respectively. By looking at the monitor 120, the driver can check the presence and behavior of passengers and animals (image subjects) such as assistance dogs (guide dogs) getting on and off through the doors of the first vehicle V1 or the second vehicle V2.

The imaging data acquired by the first camera 11N and the second camera 11D is transmitted to the display control device 310 via a communication cable (wiring). The display control device 310 controls the display mode when the imaging data is displayed on the monitor 120.

The storage unit 320 also records (1) the control programs of each unit, (2) the OS program, (3) the application programs, and (4) various data read when these programs are executed by the display control device 310. The storage unit 320 is configured from a non-volatile storage device such as a hard disk or flash memory.

Figure 10 is a diagram showing an example of the display screen of the monitor 120. As shown in Figure 10, the monitor 120 displays, on the left side of the display screen, an image IM1 captured by a first camera 11N (referred to as the operating camera C), which is a camera C located at the first end E1 on the forward side in the traveling direction D1 of the train 1 and is located on the platform PF side. In the example shown in Figure 1, the camera C11 is the operating camera C. In addition, on the right side of the display screen of the monitor 120, an image IM2 captured by a second camera 11D provided on the operating camera C is displayed.

Which of the multiple cameras C is to be the operating camera C may be designated by the driver (crew member), or may be determined by the display control device 310 according to the vehicle's operating conditions. For example, the correspondence between the vehicle's position information and the camera C to be operated may be stored in advance in the memory unit 320, and the display control device 310 may identify the camera C to be operated based on the vehicle's position information.

As described above, the monitoring system 300 in this embodiment is a system that monitors the doors and their surroundings on a train 1 that is provided with multiple doors (doors 101-106, 201-206) for boarding and alighting. The monitoring system 300 includes a first camera 11N and a second camera 11D that are provided on the side of the first end E1 of a vehicle (e.g., the first vehicle V1) and face the second end E2 of the vehicle to capture images of subjects boarding and alighting through at least some of the multiple doors, and a display device (e.g., a monitor 120) that displays images shown by the imaging data of the first camera 11N and the second camera 11D.

The above configuration makes it possible to reduce the amount of equipment, such as wiring, required to install the first camera 11N and the second camera 11D compared to when multiple car-side cameras are installed at separate locations on the train 1. This makes it easier to build a monitoring system 300 on the train 1.

As mentioned above, the first camera 11N and the second camera 11D do not have to be housed in the housing 5, and the same effect as described above can be achieved even if the first camera 11N and the second camera 11D are installed adjacent to each other on the side of the train 1 as separate imaging devices.

A vehicle in which the first camera 11N and the second camera 11D are installed (first vehicle V1 in the example shown in FIG. 8) is referred to as a specific vehicle. The monitor 120 is installed in the specific vehicle. In the monitoring system 300 in this embodiment, wiring connecting the first camera 11N and the second camera 11D to the monitor 120 may be installed only in the specific vehicle. In such a monitoring system 300, it is possible to eliminate the need to install a communication cable for displaying on the monitor 120, which is different from the control circuit in the train 1, between the first vehicle V1 and the second vehicle V2. Therefore, equipment such as wiring can be effectively simplified.

(Other configuration examples)
The display control device 310 may display the image IM1 of the first camera 11N and the image IM2 of the second camera 11D at the same size, or may display the image IM2 of the second camera 11D larger than the image IM1 of the first camera 11N. Since the second camera 11D is a camera that captures an image of a relatively distant object, the display mode makes it easier to view the imaged subject captured by the second camera 11D.

[Additional Notes]
The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

1 Train 11D Second camera 11N First camera 101-106 Door AX1 First optical axis AX2 Second optical axis C11 Camera V1 First car V2 Second car

Claims (6)

A binocular camera that captures images of subjects getting on and off through a plurality of doors provided on a train,
a first camera having a first optical axis and a first focal length;
a second camera having a second optical axis non-parallel to the first optical axis and a second focal length longer than the first focal length. a substrate to which the first camera and the second camera are fixed,
The camera according to claim 1 , wherein the angle of the first optical axis relative to the second optical axis is adjustable by changing a fixed position of the first camera on the substrate. A train equipped with multiple doors for boarding and alighting,
a first camera and a second camera that are provided on a side surface at a first end of the train, facing a second end of the train, and capture images of subjects getting on and off through at least some of the plurality of doors;
the first camera has a first optical axis and a first focal length;
the second camera has a second optical axis and a second focal length longer than the first focal length;
A train, wherein an angle between the second optical axis and a horizontal direction is smaller than an angle between the first optical axis and a horizontal direction. a first vehicle and a second vehicle each having at least one said door;
the first camera and the second camera are provided in the first vehicle,
The train according to claim 3 , wherein the second camera captures an image of an object getting on or off through the door of the second car. A monitoring system for a train having multiple doors for boarding and alighting, comprising:
The train has a plurality of cars,
a first camera and a second camera provided on a side surface of a first end portion of the vehicle, facing a second end portion of the vehicle, and configured to capture an image of an object getting on or off through at least some of the plurality of doors;
a display device that displays images represented by the imaging data of the first camera and the second camera,
the first camera has a first optical axis and a first focal length;
the second camera has a second optical axis and a second focal length longer than the first focal length;
A surveillance system, wherein an angle between the second optical axis and a horizontal direction is smaller than an angle between the first optical axis and a horizontal direction. the display device is installed in a specific vehicle, among the plurality of vehicles, in which the first camera and the second camera are provided;
The surveillance system according to claim 5 , wherein wiring connecting the first camera and the second camera to the display device is provided only within the specific vehicle.

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