The present invention relates to a sensor device, a control device, a control method, a program, and a storage medium.
In recent years, various sensor devices such as light detection and ranging (LiDAR) have been developed. The sensor device includes a scanning unit, such as a micro electro mechanical systems (MEMS) mirror, and a light detecting unit that detects reflected light of a spot generated by the scanning unit.
Patent Document 1 describes an example of the sensor device. The sensor device includes a plurality of light receiving elements and an optical element that guides reflected light to each of the plurality of light receiving elements at predetermined time intervals. In a pixel of each light receiving element, an image formation position of an image by the reflected light is shifted by half the pitch of the pixel. By combining image data generated by each light detecting unit, it is possible to detect an object with a higher resolution as compared with a case of using a single light detecting unit.
In recent sensor devices, there may be a need not only to detect objects with a high resolution but also to detect objects with a wide-angle lens and to detect objects with a telephoto lens. In a case where both a function of detecting objects with a wide-angle lens and a function of detecting objects with a telephoto lens are required, it is desirable for both the functions to be implemented by a single sensor device.
An example of the problem to be solved by the present invention is to switch a sensor device between a mode for detecting an object with a wide-angle lens and a mode for detecting an object with a telephoto lens.
According to the invention described in claim 1,
According to the invention described in claim 5,
According to the invention described in claim 6,
According to the invention described in claim 7,
According to the invention described in claim 8,
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same constituent elements are designated by the same reference numerals, and the description thereof will not be repeated as appropriate.
In the present specification, unless otherwise specified, ordinal numbers such as “first”, “second”, “third”, and the like are added merely to distinguish configurations with similar names and do not imply specific characteristics of the configuration (for example, order or importance).
In
The first direction X is one direction parallel to a horizontal direction orthogonal to a vertical direction. When viewed from the negative direction of the third direction Z, the positive direction of the first direction X is a direction from right to left in the horizontal direction, and the negative direction of the first direction X is a direction from left to right in the horizontal direction. The second direction Y is a direction parallel to the vertical direction. The positive direction of the second direction Y is a direction from bottom to top in the vertical direction, and the negative direction of the second direction Y is a direction from top to bottom in the vertical direction. The third direction Z is one direction parallel to the horizontal direction and orthogonal to the first direction X. When viewed from the negative direction of the first direction X, the positive direction of the third direction Z is a direction from left to right in the horizontal direction, and the negative direction of the third direction Z is a direction from right to left in the horizontal direction. The relationship between the first direction X, the second direction Y, the third direction Z, the horizontal direction, and the vertical direction is not limited to the example described above. The relationship between the first direction X, the second direction Y, the third direction Z, the horizontal direction, and the vertical direction varies depending on the disposition of the sensor device 10. For example, the second direction Y may be parallel to the horizontal direction.
The sensor device 10 includes a transmitting system 100, a receiving system 200, and a control unit 300. In the present embodiment, the sensor device 10 is a biaxial LiDAR in which an optical axis of light transmitted from the transmitting system 100 toward an overall field of view F, which will be described below, and an optical axis of light reflected from the overall field of view F and received by the receiving system 200 are shifted to each other. The transmitting system 100 includes a light source unit 110, a scanning unit 120, and a transmitting system lens 130. The receiving system 200 includes a light detecting unit 210 and a receiving system lens 220. A control unit 300 controls the transmitting system 100 and the receiving system 200.
The light source unit 110 is, for example, a pulsed laser. The wavelength of the light emitted from the light source unit 110 is, for example, infrared rays. The light source unit 110 emits light in a temporally repetitive manner. The emission timing of light from the light source unit 110 is controlled by the control unit 300. In
In the present embodiment, the scanning unit 120 is a MEMS mirror. The scanning unit 120 may be a scanning unit other than the MEMS mirror. The scanning unit 120 reflects the light emitted from the light source unit 110 toward a virtual plane, which is perpendicular to the third direction Z and onto which the overall field of view F is projected, and generates a spot S, which is light projected onto the virtual plane. The scanning unit 120 moves a position where the spot S is generated within the virtual plane in two directions, that is, the first direction X and the second direction Y.
In the present embodiment, the transmitting system lens 130 is a zoom lens having a plurality of lenses arranged along the optical axis of the light emitted from the light source unit 110. The control unit 300 controls the size of the spot S projected onto the virtual plane perpendicular to the third direction Z by controlling the distance between the plurality of lenses. Specifically, the size of the spot S becomes larger as the combined focal length is shortened by changing the distance between the plurality of lenses. On the other hand, the size of the spot S becomes smaller as the combined focal length is lengthened by changing the distance between the plurality of lenses. The transmitting system lens 130 may be a lens different from the zoom lens.
In the present embodiment, the light detecting unit 210 is a two-dimensional array sensor. The light detecting unit 210 detects the reflected light of the spot S. The light detecting unit 210 has a plurality of pixels P arranged in a matrix along two directions, that is, the first direction X and the second direction Y. In the example shown in
Within the overall field of view F, a plurality of fields of view f corresponding to the plurality of pixels P for each pixel of the light detecting unit 210 are arranged in a matrix in two directions, that is, the first direction X and the second direction Y. When viewed from the negative direction of the third direction Z, the position of each field of view f with respect to the center of the overall field of view F is inverted by the receiving system lens 220 in the first direction X and the second direction Y with respect to the position of each pixel P with respect to the center of the light detecting unit 210. In the example shown in
In the present embodiment, the receiving system lens 220 is a zoom lens having a plurality of lenses arranged from the light detecting unit 210 toward the overall field of view F. The control unit 300 controls the distance between the plurality of lenses to control the size of the overall field of view F projected onto the virtual plane perpendicular to the third direction Z and the sizes of the plurality of fields of view f arranged in a matrix in two directions, that is, the first direction X and the second direction Y, within the overall field of view F. Specifically, the sizes of the overall field of view F and of the plurality of fields of view f become larger as the combined focal length is shortened by changing the distance between the plurality of lenses. On the other hand, the sizes of the overall field of view F and of the plurality of fields of view f become smaller as the combined focal length is lengthened by changing the distance between the plurality of lenses. The receiving system lens 220 may be a lens different from the zoom lens.
First,
In
In
In the example shown in
The control unit 300 controls the amplitude of the drive waveform of the scanning angle of the scanning unit 120, which is used to move the spot irradiation position, to control a range (FOV) followed by the spot irradiation position when viewed from the third direction Z. Specifically, the length in the first direction X of the range followed by the spot irradiation position when viewed from the third direction Z is determined according to the amplitude of the drive waveform of the scanning angle of the scanning unit 120, which is used to move the spot irradiation position in the first direction X. The length in the second direction Y of the range followed by the spot irradiation position when viewed from the third direction Z is determined according to the amplitude of the drive waveform of the scanning angle of the scanning unit 120, which is used to move the spot irradiation position in the second direction Y.
Next,
A timing chart in the upper part of
The timing chart in the lower part of
Next, the control by the control unit 300 will be described with reference to
In a time section from the start to the end of one frame, the control unit 300 repeatedly alternates between the movement of the spot irradiation position from the positive direction to the negative direction of the first direction X and the movement of the spot irradiation position from the negative direction to the positive direction of the first direction X. Hereinafter, as necessary, the movement of the spot irradiation position from the positive direction to the negative direction of the first direction X will be referred to as negative directional movement of the spot irradiation position in the first direction X, and the movement of the spot irradiation position from the negative direction to the positive direction of the first direction X will be referred to as positive directional movement of the spot irradiation position in the first direction X. The control unit 300 increases the scanning angle AY in the time section between the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X, thereby moving the spot irradiation position from the positive direction to the negative direction of the second direction Y by a distance substantially equal to the length of the spot S in the second direction Y. The negative directional movement of the spot irradiation position in the first direction X is performed twice, and the positive directional movement of the spot irradiation position in the first direction X is performed twice. The control unit 300 controls the emission timing of light from the light source unit 110 in the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X, thereby substantially matching the irradiation pitch of the spot S in the first direction X with the array pitch of the plurality of fields of view f in the first direction X. As a result, the spot S is emitted to each field of view f through which the spot irradiation position passes in the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X.
In the time section from the start to the end of one frame, the control unit 300 substantially matches the range followed by the spot irradiation position when viewed from the third direction Z with the overall field of view F when viewed from the third direction Z. Specifically, the control unit 300 makes the length in the first direction X of the range followed by the spot irradiation position when viewed from the third direction Z substantially equal to the length of the overall field of view F in the first direction X when viewed from the third direction Z. The control unit 300 makes the length in the second direction Y of the range followed by the spot irradiation position when viewed from the third direction Z substantially equal to the length of the overall field of view F in the second direction Y when viewed from the third direction Z.
The control unit 300 returns the scanning angle AY to the initial value and ends the control for one frame. The control unit 300 repeats the control described above in each of subsequent frames.
The control of the control unit 300 is not limited to the examples shown in
For example, the control unit 300 may not match the irradiation pitch of the spot S in the first direction X in the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X with the array pitch of the plurality of fields of view f in the first direction X. For example, in a case where the speed of the negative directional movement of the spot irradiation position in the first direction X or the speed of the positive directional movement of the spot irradiation position in the first direction X is relatively high and the temporal interval of the emission timing of light from the light source unit 110 cannot be made very short because of factors such as eye safety, the irradiation pitch of the spot S in the first direction X may be larger than the array pitch of the plurality of fields of view f in the first direction X. In this case, in a certain time section, the plurality of spots S may be emitted in the first direction X at a pitch larger than the array pitch of the plurality of fields of view f in the first direction X, and in a subsequent time section following the time section, the spot S may be emitted to a position located in the first direction X between the positions irradiated with the spots S in the previous time section.
In addition, for example, the control unit 300 may move the spot irradiation position from the negative direction to the positive direction of the second direction Y by a distance longer than the length of the spot S in the second direction Y in the time section between the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X.
In the example shown in
The control unit 300 controls the receiving system lens 220 to switch between the size of the overall field of view F when viewed from the third direction Z in the example shown in
The size of the spot S when viewed from the third direction Z in the example shown in
In the time section from the start to the end of one frame, the control unit 300 sequentially performs the negative directional movement of the spot irradiation position in the first direction X and the positive directional movement of the spot irradiation position in the first direction X. The control unit 300 increases the scanning angle AY in the time section between the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X, thereby moving the spot irradiation position from the positive direction to the negative direction of the second direction Y by a distance substantially equal to the length of the spot S in the second direction Y. The control unit 300 controls the emission timing of light from the light source unit 110 in the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X, thereby substantially matching the irradiation pitch of the spot S in the first direction X with the array pitch of the plurality of fields of view f in the first direction X. As a result, the spot S is emitted to each field of view f through which the spot irradiation position passes in the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X.
In the time section from the start to the end of one frame, the control unit 300 substantially matches the range followed by the spot irradiation position when viewed from the third direction Z with the overall field of view F when viewed from the third direction Z. Specifically, the control unit 300 makes the length in the first direction X of the range followed by the spot irradiation position when viewed from the third direction Z substantially equal to the length of the overall field of view F in the first direction X when viewed from the third direction Z. The control unit 300 makes the length in the second direction Y of the range followed by the spot irradiation position when viewed from the third direction Z substantially equal to the length of the overall field of view F in the second direction Y when viewed from the third direction Z.
The control of the control unit 300 is not limited to the examples shown in
Next, the examples shown in
The control unit 300 varies the drive waveform of the scanning angle for moving the spot irradiation position according to the size of the overall field of view F when viewed from the third direction Z. Specifically, the control unit 300 increases the number of segments in the second direction Y followed by the spot irradiation position in a case where the length of the overall field of view F in the second direction Y is the predetermined first length as shown in
The sensor device 10 enlarges the size of the overall field of view F when viewed from the third direction Z in the mode shown in
In the examples described above, in both the example shown in
In the example shown in
The control unit 300 moves the spot irradiation position in the same aspect as the movement aspect of the spot irradiation position described with reference to
In the example shown in
In the time section from the start to the end of the first half of one frame, the control unit 300 repeatedly alternates between the negative directional movement of the spot irradiation position in the first direction X and the positive directional movement of the spot irradiation position in the first direction X. The control unit 300 increases the scanning angle AY in the time section after the end of the negative directional movement of the spot irradiation position in the first direction X and before the start of the positive directional movement of the spot irradiation position in the first direction X, thereby moving the spot irradiation position from the positive direction to the negative direction of the second direction Y by a distance substantially half the array pitch in the second direction Y of the plurality of portions arranged in the second direction Y within the spot S. The control unit 300 increases the scanning angle AY in the time section after the end of the negative directional movement of the spot irradiation position in the first direction X and before the start of the positive directional movement of the spot irradiation position in the first direction X, thereby moving the spot irradiation position from the positive direction to the negative direction of the second direction Y by a distance substantially equal to the length of the spot S in the second direction Y. The negative directional movement of the spot irradiation position in the first direction X is performed twice, and the positive directional movement of the spot irradiation position in the first direction X is performed twice. The control unit 300 controls the emission timing of light from the light source unit 110 in the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X, thereby substantially matching the irradiation pitch of the spot S in the first direction X with the array pitch of the plurality of fields of view f in the first direction X. As a result, the spot S is emitted to each field of view f through which the spot irradiation position passes in the time section of the negative directional movement of the spot irradiation position in the first direction X and the time section of the positive directional movement of the spot irradiation position in the first direction X.
In the examples shown in
The integrated circuit 400 includes a bus 402, a processor 404, a memory 406, a storage device 408, an input and output interface 410, and a network interface 412. The bus 402 is a data transmission path for the processor 404, the memory 406, the storage device 408, the input and output interface 410, and the network interface 412 to transmit and receive data to and from each other. However, a method of mutually connecting the processor 404, the memory 406, the storage device 408, the input and output interface 410, and the network interface 412 is not limited to bus connection. The processor 404 is an arithmetic processing device implemented using a microprocessor or the like. The memory 406 is a memory implemented using a random access memory (RAM) or the like. The storage device 408 is a storage device implemented using a read only memory (ROM), a flash memory, or the like.
The input and output interface 410 is an interface for connecting the integrated circuit 400 to peripheral devices. The transmitting system 100 and the receiving system 200 are connected to the input and output interface 410.
The network interface 412 is an interface for connecting the integrated circuit 400 to a network. This network is a network such as a controller area network (CAN), for example. A method for the connection of the network interface 412 to the network may be a wireless connection or a wired connection.
The storage device 408 stores program modules for implementing the function of the control unit 300. The processor 404 reads out and executes these program modules on the memory 406, thereby implementing the function of the control unit 300.
The hardware configuration of the integrated circuit 400 is not limited to the configuration shown in
Although the embodiments of the present invention have been described above with reference to the drawings, these are examples of the present invention, and various configurations other than the above can also be employed.
Filing Document | Filing Date | Country | Kind |
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PCT/JP2021/012908 | 3/26/2021 | WO |