WO2022050394A1

WO2022050394A1 - Sensor device

Info

Publication number: WO2022050394A1
Application number: PCT/JP2021/032528
Authority: WO
Inventors: 宙井上
Original assignee: 株式会社小糸製作所
Priority date: 2020-09-04
Filing date: 2021-09-03
Publication date: 2022-03-10
Also published as: JPWO2022050394A1

Abstract

A resin cover (12) forms part of the outer surface of a monitoring device and delimits a housing space (13). A light emitting part (14) is disposed in the housing space (13) and emits detection light (DL) to a detection region which is located outside a moving body. A light receiving part (15) is disposed in the housing space (13) and outputs a detection signal (DS) on the basis of detection light (DL) that returns from the detection region. An optical path correction member (16) is disposed in the housing space (13) at a position that is closer to the inner surface (12a) of the resin cover (12) than is the light emitting part (14). The shape and refractive index of the optical path correction member (16) are set such that the optical path of detection light (DL) that passes through the optical path correction member (16) and the resin cover (12) is near what the optical path of detection light (DL) would be without passing through the optical path correction member (16) and without refraction by the resin cover (12).

Description

Sensor device

This disclosure relates to a sensor device mounted on a monitoring device.

Patent Document 1 discloses a radar as an example of a sensor for detecting information outside the vehicle as an example of a monitoring device. The radar is arranged in the lighting room of the lamp device that illuminates the outside of the vehicle. That is, the radar is covered by a cover that partitions the light room and allows the passage of illumination light. The cover forms part of the outer surface of the vehicle and also allows the detection light to pass through for the radar to detect external information.

Japanese Patent Application Publication No. 2007-106199

It is to suppress the deterioration of the information detection accuracy of the sensor device that uses the detection light accompanied by the passage of the cover that forms a part of the outer surface of the monitoring device.

One aspect of the present disclosure that may be provided to meet the above requirements is a sensor device mounted on a monitoring device.
A resin cover that forms a part of the outer surface of the monitoring device and partitions the accommodation space,
A light emitting unit that is arranged in the accommodation space and emits detection light to a detection area located outside the monitoring device, and a light emitting unit.
A light receiving unit that is arranged in the accommodation space and outputs a detection signal based on the detection light returned from the detection area.
An optical path correction member arranged at a position closer to the inner surface of the resin cover than the light emitting portion in the accommodation space.
Equipped with
The shape and refractive index of the optical path correction member are the detection light when the optical path of the detected light that has passed through the optical path correction member and the resin cover does not pass through the optical path correction member and is not refracted by the resin cover. It is set to approach the optical path of.

When the resin cover has a shape extending along a concentric circle centered on the light source of the light emitting portion, the detected light emitted from the light source passes through the resin cover without being refracted. However, it is impractical to determine the actual shape of the resin cover as such. This is because the resin cover forms a part of the outer surface of the monitoring device, so that design and functionality are prioritized. Therefore, the detected light emitted from the light emitting unit with the intention of detecting information in a specific direction is reflected by an object located in a direction deviated by the amount of refraction by the resin cover.

According to the above configuration, the optical path correction member can take a path as if the detection light passed through the resin cover without being refracted before the detection light emitted from the light emitting unit passes through the resin cover. Corrects the optical path of the detected light. As a result, it is possible to suppress the occurrence of optical path deviation that may occur by passing through a resin cover with a realistic shape. Therefore, a sensor device that uses detection light that accompanies the passage of a resin cover that forms a part of the outer surface of the monitoring device. It is possible to suppress a decrease in information detection accuracy.

An example is a sensor device according to an embodiment. The vehicle in which the sensor device of FIG. 1 is mounted is shown. It is a figure explaining the function of the optical path correction member in the sensor device of FIG. It is a figure explaining the function of the optical path correction member in the sensor device of FIG. Another example of the configuration of the optical path correction member in the sensor device of FIG. 1 is shown. Another example of the configuration of the optical path correction member in the sensor device of FIG. 1 is shown. An example is shown in which the sensor device of FIG. 1 is mounted on a transportation infrastructure facility.

The example of the embodiment will be described in detail below with reference to the attached drawings. In each drawing used in the following description, the scale is appropriately changed in order to make each member a recognizable size.

In the attached drawing, the arrow F indicates the forward direction of the illustrated structure. Arrow B indicates the backward direction of the illustrated structure. The arrow L indicates the left direction of the illustrated structure. The arrow R indicates the right direction of the illustrated structure. The "left" and "right" used in the following description indicate the left-right direction as seen from the driver's seat.

FIG. 1 schematically illustrates the configuration of the sensor device 10 according to the embodiment. The sensor device 10 can be mounted on the vehicle 20 exemplified in FIG. The vehicle 20 is an example of a moving body. The vehicle 20 is also an example of a monitoring device.

In this example, the sensor device 10 is mounted on the left front part of the vehicle 20. The left front portion of the vehicle 20 is a portion located on the left side of the center in the left-right direction of the vehicle 20 and on the front side of the center in the front-rear direction of the vehicle 20. The detection area A of the sensor device 10 is set outside the vehicle 20.

As illustrated in FIG. 1, the sensor device 10 includes a housing 11 and a resin cover 12. The resin cover 12 forms a part of the outer surface of the vehicle 20. The resin cover 12 and the housing 11 partition the accommodation space 13.

The sensor device 10 includes a light emitting unit 14. The light emitting unit 14 is arranged in the accommodation space 13. The light emitting unit 14 includes a light source that emits the detected light DL to the detection region A. Examples of such a light source include semiconductor light emitting devices such as light emitting diodes (LEDs) and laser diodes (LDs). In this example, the detection light DL is invisible light. For example, infrared light having a wavelength of 905 nm can be used as the detection light DL.

The light emitting unit 14 may include a plurality of light sources that emit the detection light DL in different directions in the detection region A, respectively. Alternatively, the light emitting unit 14 may include a scanning mechanism that directs the detection light DL emitted from a single light source in different directions within the detection region A.

The detection light DL emitted from the light emitting unit 14 passes through the resin cover 12 and heads for the detection region A. That is, the resin cover 12 is made of a material having translucency at the wavelength of the detection light DL. Examples of such materials include polycarbonate, ABS resin, polyvinyl chloride, acrylic and the like.

The sensor device 10 includes a light receiving unit 15. The light receiving unit 15 is arranged in the accommodation space 13. The light receiving unit 15 includes a light receiving element having sensitivity to the wavelength of the detection light DL. The light receiving element outputs a detection signal DS based on the detection light DL returned from the detection area A by being reflected by an object located in the detection area A. Examples of such light receiving elements include photodiodes, photoresists, photoresistors, and the like.

The detection signal DS is transmitted to a control device (not shown). The control device may be mounted on the housing 11 as a part of the sensor device 10, or may be mounted on the vehicle 20 independently of the sensor device 10. Such a control device may be realized by a general-purpose microprocessor such as a CPU or MPU that operates in cooperation with a general-purpose memory such as RAM or ROM, or may be realized by a dedicated integrated circuit such as a microcontroller, ASIC, or FPGA. May be done.

For example, the control device has a detection light DL based on the time from the timing when the light emitting unit 14 emits the detection light DL in a certain direction in the detection region A until the light receiving unit 15 receives the detection light DL returned from the direction. You can get the distance information to the object that reflected the light. Further, by accumulating such distance information in association with the emission direction of the detection light DL, the control device can acquire information relating to the shape of the object located in the detection region A. In addition to or instead, the control device is an object that reflects the detection light DL based on the difference between the waveform of the detection light DL emitted from the light emitting unit 14 and the waveform of the detection light DL received by the light receiving unit 15. Information related to attributes such as the material of the light can be acquired.

The sensor device 10 includes an optical path correction member 16. The optical path correction member 16 is arranged in the accommodation space 13 at a position closer to the inner surface 12a of the resin cover 12 than the light emitting portion 14. The optical path correction member 16 is arranged so as to allow the detection light DL emitted from the light emitting unit 14 and the detection light DL returned from the detection region A to pass through. That is, the optical path correction member 16 has translucency at the wavelength of the detected light DL.

The function of the optical path correction member 16 will be described with reference to FIGS. 3 and 4. FIG. 3 illustrates an optical path of the detection light DL that passes through the resin cover 12 when the optical path correction member 16 is not arranged. FIG. 4 illustrates the optical path of the detection light DL passing through the optical path correction member 16 and the resin cover 12.

As illustrated in FIG. 3, the detection light DL emitted from the light emitting unit 14 is incident on the inner surface 12a of the resin cover 12. Since the refractive index of the material forming the resin cover 12 is different from the refractive index of air, the detection light DL incident on the inner surface 12a is refracted. The refracted detection light DL travels inside the resin cover 12 and is emitted from the outer surface 12b. The detection light DL emitted from the outer surface 12b into the air is also refracted. The two-dot chain line represents an optical path P0 when the detection light DL incident on the inner surface 12a of the resin cover 12 goes straight without being refracted. The optical path P1 of the detection light DL that has passed through the resin cover 12 while undergoing refraction deviates from the optical path P0. The deviation amount d is expressed by the following equation.

t represents the thickness dimension of the resin cover 12. θ represents the angle formed by the optical path P1 of the detection light DL with respect to the normal direction of the outer surface 12b of the resin cover 12. n ₁ represents the refractive index of air. n ₂ represents the refractive index of the resin cover 12.

The above description is also applicable to the detection light DL that returns from the detection region A, passes through the resin cover 12, and is received by the light receiving unit 15.

When the inner surface 12a and the outer surface 12b of the resin cover 12 have a shape extending along a concentric circle centered on the light source of the light emitting unit 14, the detected light DL emitted from the light source is not refracted. It passes through the resin cover 12. However, it is unrealistic to determine the actual shape of the resin cover 12 as such. This is because the resin cover 12 forms a part of the outer surface of the vehicle 20, so that design and functionality are prioritized. Therefore, the detection light DL emitted from the light emitting unit 14 with the intention of detecting an object in a specific direction passes through the resin cover 12 and is reflected by an object located in the direction deviated by the above-mentioned deviation amount d. Will receive.

In FIG. 4, the solid line represents the optical path P2 of the detection light DL passing through the optical path correction member 16 and the resin cover 12. The broken line represents the optical path P1 of the detection light DL that passes through the resin cover 12 when the optical path correction member 16 is not provided (the same as that illustrated by the solid line in FIG. 3). The alternate long and short dash line represents the optical path P0 of the detection light DL when it does not pass through the optical path correction member 16 and is not refracted by the resin cover 12 (same as that exemplified by the alternate long and short dash line in FIG. 3). The shape and refractive index of the optical path correction member 16 are determined so that the optical path P2 of the detection light DL that has passed through the optical path correction member 16 and the resin cover 12 approaches the optical path P0. In the example shown in FIG. 4, the optical path P2 coincides with the optical path P0.

That is, the optical path correction member 16 can take a path as if the detected light DL emitted from the light emitting unit 14 passed through the resin cover 12 without being refracted before passing through the resin cover 12. It is configured to correct the optical path of the detection light DL as described above. As a result, it is possible to suppress the occurrence of optical path deviation that may occur by passing through the resin cover 12 having a realistic shape. Therefore, the detection light DL accompanied by the passage of the resin cover 12 forming a part of the outer surface of the vehicle 20 is used. It is possible to suppress a decrease in the information detection accuracy of the sensor device 10.

The optical path correction member 16 preferably has a portion formed of a material having a refractive index higher than that of the material forming the resin cover 12. According to such a configuration, it is easy to enhance the correction effect of the optical path. An example of such a material is glass.

FIG. 5 illustrates a plurality of detection lights DL1 to DL3 emitted from the light emitting unit 14 in different directions. As described above, the plurality of detection lights DL1 to DL3 may be emitted from a plurality of independent light sources, or the detection lights emitted from a single light source are directed in different directions by the scanning mechanism. It may be a light source.

In this example, the optical path correction member 16 is provided for each of the detected lights DL1 to DL3. Similar to FIG. 4, the solid line represents the optical path of each detected light passing through each optical path correction member and the resin cover 12. The broken line represents the optical path of each detected light passing through the resin cover 12 when each optical path correction member is not provided. The two-dot chain line represents the optical path of each detected light when it does not pass through each optical path correction member and is not refracted by the resin cover 12. That is, the shape and refractive index of each optical path correction member 16 is the case where the optical path of the detected light that has passed through the optical path correction member 16 and the resin cover 12 does not pass through the optical path correction member and is not refracted by the resin cover 12. It is set to approach the optical path P0 of the detected light.

In this example, each optical path correction member 16 has a first portion 161, a second portion 162, and a third portion 163. The refractive index of the first portion 161 and the refractive index of the third portion 163 are higher than the refractive index of the second portion 162. That is, the second portion 162 is located between the first portion 161 and the third portion 163 along the path of the detection light DL passing through the optical path correction member 16.

If the material has a refractive index higher than that of the material forming the second portion 162, the material forming the first portion 161 and the material forming the third portion 163 are the same. It may or may not be different. For example, a first portion 161 and a third portion 163 made of glass can be joined to a second portion 162 made of acrylic. Alternatively, a second portion 162 as a hollow portion may be formed in a member including the first portion 161 and the third portion 163 made of glass or acrylic.

According to such a configuration, since the refraction of the detected light DL is repeated inside the optical path correction member 16, it is easy to enhance the optical path correction effect. By selecting the material forming at least one of the first portion 161 and the third portion 163 so as to have a refractive index higher than the refractive index of the material forming the resin cover 12, the optical path correction effect can be further enhanced.

In this example, the first portion 161 and the third portion 163 of each optical path correction member 16 have a shape that functions as a so-called plano-convex lens. However, the respective shapes of the first portion 161 and the third portion 163 can be shaped to function as either a plano-concave lens, a positive meniscus lens, or a negative meniscus lens.

As illustrated in FIG. 6, a single optical path correction member 160 in which the plurality of optical path correction members 16 exemplified in FIG. 5 are integrated can be provided. The optical path correction member 160 according to this example includes a connecting portion 164 for connecting the first portions 161 of two adjacent optical path correction members 16 adjacent to each other and a connecting portion 165 for connecting the third portions 163 to each other. The material forming the connecting portion 164 may be the same as or different from the material forming the first portion 161. The material forming the connecting portion 165 may be the same as or different from the material forming the third portion 163. The optical path correction member 160 according to this example has a monolithic second portion 162. However, the second portion 162 may be formed only in the portion through which each of the detection lights DL1 to DL3 passes.

As illustrated in FIG. 1, the optical path correction member 16 (160) can be fixed to the inner surface 12a of the resin cover 12. The fixing method can be appropriately selected from adhesion, joining, welding, screwing and the like. Although specific illustration is omitted, the portion of the optical path correction member 16 (160) through which the detection light DL (DL1 to DL3) does not pass is provided for fixing to the inner surface 12a of the resin cover 12.

According to such a configuration, it is possible to suppress a change in the relative position that may occur between the optical path correction member 16 (160) and the resin cover 12 due to vibration from the vehicle 20 or the like. As described above, the shape of the optical path correction member 16 (160) is determined in consideration of the refraction of the detected light DL by the resin cover 12. Therefore, by suppressing the change in the relative position that may occur between the optical path correction member 16 (160) and the resin cover 12, it is possible to enhance the effect of suppressing a decrease in the information detection accuracy of the sensor device 10.

However, the optical path correction member 16 may be fixed in the accommodation space 13 via an appropriate fixing member. For example, the optical path correction member 16 may be fixed to a decorative member such as an extension so as to face the inner surface 12a of the resin cover 12.

As illustrated in FIG. 1, the sensor device 10 may include a lamp 17 that emits illumination light LL to the outside of the vehicle 20. The illumination light LL is visible light. Examples of the lamp 17 include headlights, side lights, turn signal lamps, fog lamps, and the like.

The lamp 17 is arranged in the accommodation space 13. Therefore, the resin cover 12 is configured to allow the passage of the illumination light LL emitted from the lamp 17. That is, the resin cover 12 has a light passing region 12c that allows the passing of the illumination light LL. In this case, at least the light passing region 12c in the resin cover 12 is formed of a material transparent to the illumination light LL.

The lighting fixture 17 is generally installed in a place where there is little obstruction in the vehicle 20 because of the function of supplying the illumination light LL to the outside of the vehicle 20. By arranging the sensor device 10 in such a place, information on the outside of the vehicle 20 can be efficiently detected.

The above embodiment is merely an example for facilitating the understanding of the present disclosure. The configuration according to the above embodiment may be appropriately changed or improved without departing from the spirit of the present disclosure.

In the above embodiment, the sensor device 10 is mounted on the left front portion of the vehicle 20. However, depending on the position of the detection region A set on the outside of the vehicle 20, at least one sensor device 10 may be mounted at an appropriate position on the vehicle 20. For example, a sensor device 10 having a symmetrical configuration with the sensor device 10 illustrated in FIG. 1 may be mounted on the right front portion of the vehicle 20. The right front portion of the vehicle 20 is a portion located on the right side of the center in the left-right direction of the vehicle 20 and on the front side of the center in the front-rear direction of the vehicle 20.

Similarly, a sensor device 10 may be mounted on the left rear portion or the right rear portion of the vehicle 20 in order to detect the information in the detection area A including at least the rear of the vehicle 20. The left rear portion of the vehicle 20 is a portion located on the left side of the center in the left-right direction of the vehicle 20 and on the rear side of the center in the front-rear direction of the vehicle 20. It can be mounted on the right rear part of the vehicle 20. The right rear portion of the vehicle 20 is a portion located on the right side of the center in the left-right direction of the vehicle 20 and rearward of the center in the front-rear direction of the vehicle 20. In this case, the lamp 17 may be a tail lamp, a brake lamp, a reverse lamp, or the like.

The moving body on which the sensor device 10 is mounted is not limited to the vehicle 20. Examples of other moving objects include railroads, flying objects, aircraft, ships and the like. The mobile body on which the sensor device 10 is mounted does not have to require a driver.

The sensor device 10 does not necessarily have to be mounted on a moving body. As illustrated in FIG. 7, the sensor device 10 can also be mounted on traffic infrastructure equipment such as a street light 30 and a traffic signal 40. In this case, the transportation infrastructure equipment can be an example of a monitoring device.

When the sensor device 10 is mounted on the street light 30 or the traffic signal 40, pedestrians 50, vehicles, etc. located in the area A1 can be detected. That is, the detection region A illustrated in FIG. 2 is set in the region A1. For example, when it is detected that a pedestrian 50 or a vehicle is about to enter an intersection, the information can be notified to the vehicle 20 trying to enter the intersection from another direction via communication. Alternatively, information (characters, signs, blinking warning colors, etc.) that calls attention to the vehicle 20 trying to enter the intersection from another direction may be drawn in the area A2 by another light source that emits visible light.

The contents of Japanese Patent Application No. 2020-149038 filed on September 4, 2020 are incorporated as a part of this disclosure.

Claims

It is a sensor device mounted on a monitoring device.
A resin cover that forms a part of the outer surface of the monitoring device and partitions the accommodation space,
A light emitting unit that is arranged in the accommodation space and emits detection light to a detection area located outside the monitoring device, and a light emitting unit.
A light receiving unit that is arranged in the accommodation space and outputs a detection signal based on the detection light returned from the detection area.
An optical path correction member arranged at a position closer to the inner surface of the resin cover than the light emitting portion in the accommodation space.
Equipped with
The shape and refractive index of the optical path correction member are the detection light when the optical path of the detected light that has passed through the optical path correction member and the resin cover does not pass through the optical path correction member and is not refracted by the resin cover. It is set to approach the optical path of
Sensor device.
The optical path correction member has a portion formed of a material having a refractive index higher than that of the material forming the resin cover.
The sensor device according to claim 1.
The optical path correction member has a pair of first portions having a first refractive index, a second portion having a second refractive index smaller than the first refractive index, and a third refractive index larger than the second refractive index. Contains the third part,
The second portion is located between the first portion and the third portion along the traveling direction of the detection light passing through the optical path correction member.
The sensor device according to claim 1.
The refractive index of the material forming at least one of the first portion and the third portion is higher than the refractive index of the material forming the resin cover.
The sensor device according to claim 3.
The optical path correction member is fixed to the inner surface of the resin cover.
The sensor device according to any one of claims 1 to 4.
It is arranged in the accommodation space and is equipped with a lamp that emits illumination light to the outside of the monitoring device.
The resin cover also allows the passage of the illumination light.
The sensor device according to any one of claims 1 to 5.
The monitoring device is a mobile body.
The sensor device according to any one of claims 1 to 6.