JP6982840B2 - Sensor device - Google Patents

Description

The present invention relates to a sensor device.

Patent Document 1 discloses a LiDAR (Light Detection and Ranging) device including a rotatable laser transmitting / receiving means and a reflecting mirror having a parabolic shape. The center of rotation of the laser transfer means is located at the focal point of the parabola of the reflector. Therefore, the path of the light emitted from the laser transmitting / receiving means and reflected by the reflecting mirror is parallel to the axis of the parabola.

U.S. Patent Application Publication No. 2011/0040482

In a sensor device using a LiDAR device as described in Patent Document 1, the light emitted from the sensor unit in the axial direction of the parabola is reflected by the reflector and then re-entered into the sensor unit. At this time, noise may occur due to the sensor unit receiving reflected light different from the reflected light from the object to be measured. As a result, the sensor device may not be able to secure sufficient detection accuracy.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a sensor device having improved detection accuracy.

According to one aspect of the present invention, it is a sensor unit that emits light and receives light reflected from an object, and can perform scanning that rotates the direction of the emitted light around a predetermined rotation axis. It has a sensor unit and a first reflective surface that reflects light emitted from the sensor unit, and at least a part of the first reflective surface in a cross section perpendicular to the axis of rotation. Provided is a sensor device comprising a first reflecting mirror forming a parabolic beam, wherein the first reflecting surface is provided at a position other than the apex of the parabolic line.

According to the present invention, it is possible to provide a sensor device with improved detection accuracy.

It is a schematic diagram which shows the schematic structure of the object detection system including the distance measuring device which concerns on 1st Embodiment. It is a perspective schematic diagram which shows the structure of the distance measuring apparatus which concerns on 1st Embodiment. It is a front schematic diagram which shows the structure of the distance measuring apparatus which concerns on 1st Embodiment. It is a top surface schematic diagram which shows the structure of the distance measuring apparatus which concerns on 1st Embodiment. It is an optical path diagram when the reflection plane is provided at the apex of a parabola. It is an optical path diagram in the case where the reflection surface is not provided at the apex of a parabola. It is an optical path diagram in the case where the reflection surface is not provided at the apex of a parabola. It is a top surface schematic diagram which shows the structure of the distance measuring apparatus which concerns on 2nd Embodiment. It is a top surface schematic diagram which shows the structure of the distance measuring apparatus which concerns on 3rd Embodiment. It is a perspective schematic diagram which shows the structure of the distance measuring apparatus which concerns on 4th Embodiment. It is a top surface schematic diagram which shows the structure of the distance measuring apparatus which concerns on 4th Embodiment. It is sectional drawing of the logarithmic spiral reflector of the distance measuring apparatus which concerns on 4th Embodiment. It is a figure explaining the reflection of light in the reflection surface forming a logarithmic spiral. It is a front schematic diagram which shows the structure of the distance measuring apparatus which concerns on 5th Embodiment. It is a top surface schematic diagram which shows the structure of the distance measuring apparatus which concerns on 5th Embodiment. It is a perspective schematic diagram which shows the structure of the distance measuring apparatus which concerns on 6th Embodiment. It is a top surface schematic diagram which shows the structure of the distance measuring apparatus which concerns on 6th Embodiment. It is a perspective schematic diagram which shows the structure of the article display shelf which concerns on 7th Embodiment. It is a side schematic diagram which shows the structure of the article display shelf which concerns on 7th Embodiment. It is a front schematic diagram which shows the structure of the article display shelf which concerns on 8th Embodiment. It is a side schematic diagram which shows the structure of the article display shelf which concerns on 9th Embodiment. It is a perspective schematic diagram which shows the structure of the article display shelf which concerns on 10th Embodiment. It is a front schematic diagram which shows the structure of the distance measuring apparatus which concerns on 11th Embodiment. It is a front schematic diagram which shows the structure of the distance measuring apparatus which concerns on 12th Embodiment.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. Similar elements or corresponding elements may be designated by the same reference numerals in the drawings, and the description thereof may be omitted or simplified.

[First Embodiment]
FIG. 1 is a schematic diagram showing a schematic configuration of an object detection system including the distance measuring device 100 according to the first embodiment. The object detection system includes a distance measuring device 100 and a control device 200.

The distance measuring device 100 is, for example, a LiDAR device. The distance measuring device 100 can acquire the distribution of the distance from the distance measuring device 100 by emitting light into a predetermined range and detecting the reflected light from the object 10. The ranging device 100 may be more commonly referred to as a sensor device. Although one ranging device 100 is shown in FIG. 1, the object detection system may be configured to include a plurality of ranging devices 100. In the present specification, the light is not limited to visible light, but includes light such as infrared rays and ultraviolet rays that cannot be visually recognized by the naked eye.

The control device 200 is, for example, a computer. The control device 200 includes an interface (I / F) 210, a control unit 220, a signal processing unit 230, and a storage unit 240. The interface 210 is a device for connecting the control device 200 and the distance measuring device 100 so as to be communicable by wire or wirelessly. As a result, the control device 200 and the distance measuring device 100 are communicably connected. The interface 210 can be, for example, a communication device based on a standard such as Ethernet (registered trademark). The interface 210 may include a relay device such as a switching hub. When the object detection system includes a plurality of distance measuring devices 100, the control device 200 can control the plurality of distance measuring devices 100 by relaying with a switching hub or the like.

The control unit 220 controls the operation of the distance measuring device 100. The signal processing unit 230 acquires the distance information of the object 10 within the detection range by processing the signal acquired from the distance measuring device 100. The functions of the control unit 220 and the signal processing unit 230 can be realized, for example, by a processor such as a CPU (Central Processing Unit) provided in the control device 200 reading a program from the storage device and executing the program. The storage unit 240 is a storage device that stores data acquired by the distance measuring device 100, a program used for the operation of the control device 200, data, and the like. As a result, the control device 200 has a function of controlling the distance measuring device 100 and a function of analyzing the signal acquired by the distance measuring device 100.

The configuration of the object detection system described above is an example, and the object detection system may further include a device that collectively controls the distance measuring device 100 and the control device 200. Further, the object detection system may be an integrated device in which the function of the control device 200 is incorporated in the distance measuring device 100.

FIG. 2 is a schematic perspective view showing the structure of the distance measuring device 100 according to the first embodiment. FIG. 3 is a schematic view showing a structure of the distance measuring device 100 as viewed from the front. FIG. 4 is a schematic view showing a structure of the distance measuring device 100 as viewed from above. The structure of the ranging device 100 will be described with reference to these figures. It should be noted that the x-axis, y-axis, and z-axis shown in each figure are attached for the sake of explanation, and do not limit the installation direction of the distance measuring device 100.

As shown in FIG. 2, the distance measuring device 100 includes a substrate 110, a lid 120, a sensor unit 130, a parabolic reflector 140, a position adjusting mechanism 150, a planar reflector 160, and a mounting portion 170.

The substrate 110 is a rectangular plate-shaped member and functions as a part of the housing of the distance measuring device 100. Further, the substrate 110 has a function of fixing the sensor unit 130, the parabolic reflector 140, the planar reflector 160, and the like at predetermined positions.

The lid 120 is a lid that covers the substrate 110, and functions as a part of the housing of the distance measuring device 100. A parabolic reflector 140, a position adjusting mechanism 150, and a planar reflector 160 are arranged in the internal space of the housing surrounded by the substrate 110 and the lid 120.

The sensor unit 130 is a two-dimensional LiDAR device. As shown in FIG. 3, the sensor unit 130 is capable of rotational scanning around the rotation axis u. The sensor unit 130 includes a laser device that emits laser light and a photoelectric conversion element that receives the reflected light reflected by the object 10 and converts it into an electric signal. The sensor unit 130 is arranged in a notch formed below the substrate 110 and the lid 120 as shown in FIG. The light emitted from the sensor unit 130 is incident on the reflecting surface 140a of the parabolic reflector 140.

As an example of the distance detection method by the sensor unit 130, a TOF (Time Of Flight) method can be used. The TOF method is a method of measuring a distance by measuring the time from the emission of light to the reception of reflected light.

The laser light emitted from the sensor unit 130 may be visible light or invisible light such as infrared light. It is desirable that the emitted light is invisible light in order not to cause discomfort to the user in the use of entering / exhibiting detection of the goods display shelf, which will be described later. The laser light can be, for example, infrared light having a wavelength of 905 nm.

The parabolic reflector 140 is a reflector having a reflecting surface 140a. The parabolic reflector 140 is sometimes referred to as a first reflector. Further, the reflecting surface 140a may be referred to as a first reflecting surface. The reflection surface 140a forms a parabola whose focal point is a point on the rotation axis u in a cross section perpendicular to the rotation axis u (xy plane in FIG. 3). In other words, the sensor unit 130 is arranged near the focal point of the parabola formed by the reflecting surface 140a, and the rotation axis u is arranged at a position passing through the focal point of the parabola formed by the reflecting surface 140a. The axis of rotation u is parallel to the z-axis in FIG. The parabolic equation is expressed by the following equation (1) when the coordinates of the vertices of the parabola are P (0,0) and the coordinates of the focal point are F (a, 0).

Due to the mathematical nature of the parabola, when the light emitted from the sensor unit 130 is reflected by the reflecting surface 140a, the emission direction of the reflected light is parallel to the axis of the parabola regardless of the angle of the emitted light. That is, as shown in FIG. 3, in the optical path L1 and the optical path L2 having different emission angles from the sensor unit 130, the reflected light on the reflecting surface 140a is parallel to each other. By arranging the sensor unit 130 at the focal point of the reflecting surface 140a in this way, parallel scanning in which the optical path moves in parallel in the y-axis direction according to the rotation of the emitted light becomes possible.

The material of the parabolic reflector 140 may be, for example, an aluminum alloy containing aluminum as a main component. In this case, the reflective surface 140a can be formed, for example, by smoothing the surface of the aluminum alloy by mirror polishing or plating. Other parabolic reflectors, which will be described later, can also be formed by the same material and construction method.

The planar reflecting mirror 160 is a reflecting mirror having a reflecting surface 160a having at least a partially planar surface. The plane reflector 160 is sometimes called a third reflector. The reflecting surface 160a is provided on the optical path of the reflected light on the reflecting surface 140a. As shown in FIGS. 3 and 4, the planar reflecting mirror 160 changes the direction of the light reflected by the reflecting surface 140a to a direction different from that in the xy plane. More specifically, the light reflected by the plane reflector 160 is in the substantially z-axis direction, that is, in a direction substantially parallel to the rotation axis u. The light reflected by the planar reflector 160 is emitted to the outside of the distance measuring device. As a result, the direction of the emitted light from the distance measuring device 100 is not limited to the direction parallel to the axis of the reflecting surface 140a.

As with the parabolic reflector 140, the material of the planar reflector 160 may be, for example, an aluminum alloy containing aluminum as a main component. In this case, the reflecting surface 160a of the plane reflecting mirror 160 may be formed by the same smoothing as the reflecting surface 140a, but may be formed by attaching an aluminum alloy plate having a mirror surface gloss to the base material. .. It should be noted that other planar reflectors described later can also be formed by the same material and construction method.

Here, the lid 120 is configured so as not to absorb or reflect the light reflected by the plane reflecting mirror 160. Specifically, for example, the region of the lid 120 through which the reflected light of the plane reflecting mirror 160 passes can be formed of a transparent material. An example of a transparent material is an acrylic resin. Alternatively, a window may be provided such that the region through which the light reflected by the plane reflecting mirror 160 of the lid 120 passes is hollow.

The attachment portion 170 is a portion for attaching and fixing the distance measuring device 100 to an article display shelf or the like. By fixing with the mounting portion 170, the distance measuring device 100 can be mounted in any direction. The position adjusting mechanism 150 is a mechanism for finely adjusting the position of the planar reflector 160 when the distance measuring device 100 is attached to an article display shelf or the like. In addition, instead of the position adjusting mechanism 150, a drive mechanism for moving the planar reflector 160 may be provided.

The optical paths L1 and L2 shown in FIGS. 3 and 4 show an optical path when light is emitted from the sensor unit 130 to the outside. On the other hand, the light reflected by the object 10 and incident on the distance measuring device 100 passes through substantially the same path as the optical paths L1 and L2 in the opposite direction and is received by the sensor unit 130.

The distance measuring device 100 of the present embodiment has a structure thick in the axial direction of the parabolic reflector 140 due to the thickness of the parabolic reflector 140, restrictions on the arrangement position of the sensor unit 130, and the like. On the other hand, the distance measuring device 100 of the present embodiment includes a planar reflecting mirror 160 that reflects the light reflected by the parabolic reflecting mirror 140. The planar reflector 160 can change the direction of the emitted light from the ranging device 100 to a direction different from the direction of the axis of the parabola formed by the parabolic reflector. Therefore, in the distance measuring device 100 of the present embodiment, the light emitting direction can be set to a direction different from the axial direction of the parabolic reflector 140, so that the thickness of the light emitting direction can be reduced. As a result, the distance measuring device 100 of the present embodiment can be easily installed in a narrow place such as between article display shelves. Therefore, according to the present embodiment, the distance measuring device 100 having an improved degree of freedom in the installation location is provided.

Further, in the distance measuring device 100 of the present embodiment, the reflecting surface 140a of the parabolic reflecting mirror 140 is provided so as to exclude the apex of the parabola. The reason for this configuration will be described with reference to FIGS. 5 to 7.

FIG. 5 is an optical path diagram in the case where the reflection surface 140b is provided at the apex P of the parabola. For simplification of the description, the sensor unit 130 is simply displayed as a point light source arranged at the focal point F of the reflecting surface 140b. If the light emitted from the focal point F is not parallel to the axis of the parabola (not in the direction toward the vertex P), the reflected light does not pass through the focal point F. However, when the light emitted from the focal point F is parallel to the axis of the parabola (direction toward the apex P) and is reflected at the apex P, the reflected light passes through the focal point F. Therefore, the light emitted from the sensor unit 130 re-enters the sensor unit 130. In this case, noise may be generated in the measured signal by receiving the reflected light different from the reflected light from the object 10 by the sensor unit 130. As described above, when the reflection surface 140b is provided at the apex P of the parabola, the detection accuracy may be lowered and sufficient detection accuracy may not be ensured.

On the other hand, in the distance measuring device 100 of the present embodiment, as shown in FIG. 6, the reflecting surface 140a is provided so as to exclude the apex P of the parabola. Therefore, the light emitted from the focal point F is not reflected even when it is parallel to the axis of the parabola. Therefore, since the reflected light does not re-enter the sensor unit 130, it is possible to suppress a decrease in detection accuracy. As described above, according to the present embodiment, the distance measuring device 100 having improved detection accuracy is provided by providing the reflecting surface 140a of the parabolic reflecting mirror 140 so as to exclude the apex of the parabola. ..

In FIG. 6, the reflecting surface 140a is arranged on one side of the axis of the parabola, but as in the modified example shown in FIG. 7, the reflecting surface 140c is arranged on both sides except the apex P of the parabola. There may be. A specific configuration example corresponding to this modification will be described later.

[Second Embodiment]
Next, as a second embodiment of the present invention, a configuration example of a distance measuring device capable of translating a plane reflecting mirror will be described. The description of the elements common to the above-described embodiments will be omitted or simplified.

FIG. 8 is a schematic view showing the structure of the distance measuring device 101 of the present embodiment as viewed from above. The distance measuring device 101 of the present embodiment is provided with a drive mechanism 151 instead of the position adjusting mechanism 150, and is provided with a planar reflecting mirror 161 instead of the planar reflecting mirror 160. The drive mechanism 151 drives the planar reflector 161 parallel to the axial direction (x-axis direction in FIG. 8) of the parabolic reflector 140. The drive mechanism 151 includes a drive device such as a motor. Further, the drive mechanism 151 includes a device for acquiring the position information of the planar reflector 161 such as an encoder. These devices are controlled by the control device 200. Further, the position information of the planar reflector 161 acquired by the drive mechanism 151 is supplied to the control device 200.

When the planar reflector 161 is driven by the drive mechanism 151 and moves in parallel in the x-axis direction, the light reflected by the planar reflector 161 also translates in the x-axis direction. As a result, the ranging device 101 of the present embodiment enables scanning in which the light reflected by the plane reflecting mirror 161 is translated in the x-axis direction. Further, as in the first embodiment, the distance measuring device 101 of the present embodiment can also perform scanning in which the light reflected by the plane reflecting mirror 161 is translated in the y-axis direction. Therefore, the distance measuring device 101 of the present embodiment has the same effect as that of the first embodiment, and also combines two-dimensional scanning in the x-axis direction and the y-axis direction with distance measurement in the z-axis direction. As a result, it functions as a three-dimensional sensor device capable of acquiring three-dimensional position information.

[Third Embodiment]
Next, as a third embodiment of the present invention, a configuration example of a distance measuring device capable of rotating and moving a planar reflector will be described. The description of the elements common to the first embodiment will be omitted or simplified.

FIG. 9 is a schematic view showing the structure of the distance measuring device 102 of the present embodiment as viewed from above. The distance measuring device 102 of the present embodiment includes a driving mechanism 152 instead of the position adjusting mechanism 150, and a planar reflecting mirror 162 instead of the planar reflecting mirror 160. The drive mechanism 152 drives the planar reflector 162 so as to rotate about the rotation axis v parallel to the y-axis. The position of the rotation axis v may be a position where the direction of the reflected light of the plane reflecting mirror 162 changes according to the rotation, and may be, for example, on a path through which the reflected light of the parabolic reflecting mirror 140 passes. The drive mechanism 152 includes a drive device such as a motor. Further, the drive mechanism 152 includes a device for acquiring angle information of the planar reflector 162 such as an encoder. These devices are controlled by the control device 200. Further, the angle information of the planar reflector 162 acquired by the drive mechanism 152 is supplied to the control device 200.

When the planar reflecting mirror 162 is driven by the driving mechanism 152 and the planar reflecting mirror 162 rotates and moves, the direction of the reflected light by the planar reflecting mirror 162 also rotates. As a result, the ranging device 102 of the present embodiment can perform scanning by rotating and moving the direction of the reflected light by the plane reflecting mirror 162. Further, as in the first embodiment, the distance measuring device 102 of the present embodiment can also perform scanning in which the light reflected by the plane reflecting mirror 162 is translated in the y-axis direction. Therefore, the distance measuring device 102 of the present embodiment has the same effect as that of the first embodiment, and by combining rotational movement on the rotation axis v, parallel movement in the y-axis direction, and distance measurement, 3 It functions as a three-dimensional sensor device capable of acquiring dimensional position information.

[Fourth Embodiment]
Next, as a fourth embodiment of the present invention, a configuration example of a distance measuring device further including a logarithmic spiral reflector will be described. The description of the elements common to the above-described embodiments will be omitted or simplified.

FIG. 10 is a schematic perspective view showing the structure of the distance measuring device 300 according to the fourth embodiment. FIG. 11 is a schematic view showing the structure of the distance measuring device 300 as viewed from above. The structure of the ranging device 300 will be described with reference to these figures. In FIGS. 10 and 11, elements such as the substrate 110, the lid 120, and the mounting portion 170 that are not necessary for explaining the optical path may be omitted.

The distance measuring device 300 includes a sensor unit 130, a parabolic reflector 340, a drive mechanism 351 and a logarithmic spiral reflector 361 and a planar reflector 362, 363, 364, 365. The parabolic reflector 340 has reflecting surfaces 340a and 340b. The reflective surfaces 340a and 340b form a parabola whose focal point is a point on the rotation axis u in a cross section perpendicular to the rotation axis u (xy plane in FIG. 10). As shown in FIG. 11, the reflecting surface 340a and the reflecting surface 304b are in a positional relationship perpendicular to each other in the xz plane.

The light emitted from the sensor unit 130 in the negative direction of the x-axis is reflected in the z-axis direction on the reflection surface 340a, and then reflected in the positive direction of the x-axis toward the logarithmic spiral reflector 361 on the reflection surface 340b. Ru. By reflecting twice on the reflecting surfaces 340a and 340b to shift the optical path in the z direction, it is possible to prevent the reflected light from the parabolic reflector 340 from being obstructed by the sensor unit 130. Further, since the reflected light does not re-enter the sensor unit 130, the detection accuracy can be improved for the same reason as described with reference to FIGS. 5 to 7.

The logarithmic spiral reflector 361 has a columnar shape, and has a reflecting surface 361a forming a logarithmic spiral on its side surface. The light emitted from the sensor unit 130 is reflected by the reflecting surface 361a. The logarithmic spiral reflector 361 can be rotated by the drive mechanism 351 about the rotation axis w. At this time, the light reflected by the reflecting surface 361a moves in parallel according to the angle of the logarithmic spiral reflecting mirror 361.

The structure of the logarithmic spiral reflector 361 will be described in more detail with reference to FIGS. 12 and 13. FIG. 12 is a cross-sectional view of the logarithmic spiral reflector 361 according to the present embodiment on a plane perpendicular to the rotation axis w. The reflection surface 361a, which is the side surface of the logarithmic spiral reflector 361, has a closed curve in which four logarithmic spirals are continuously connected in a cross section perpendicular to the rotation axis w. By forming a closed curve in which the logarithmic spirals are continuously connected in this way, all of the reflecting surfaces 361a to which the light emitted from the sensor unit 130 can be incident have a logarithmic spiral in a cross section perpendicular to the rotation axis w. The configuration of the spiral is realized. As a result, the reflected light can be utilized for scanning regardless of which surface of the logarithmic spiral reflector 361 the light is incident on. The logarithmic spiral may also be called an equiangular spiral or a Bernoulli spiral.

FIG. 13 is a diagram illustrating light reflection on a reflective surface forming a logarithmic spiral. The logarithmic spiral Sp has r as the radial diameter in polar coordinates, θ as the deviation angle in polar coordinates, a as the value of r when the value of θ is zero, and the angle between the straight line passing through the center of the logarithmic spiral and the tangent of the logarithmic spiral. When b is set, it is expressed by the polar equation of the following equation (2).

Here, the relationship between the incident lights I11 and I21 toward the origin O of the polar equation of the equation (2) from the outside of the logarithmic spiral Sp and the reflected lights I12 and I22 will be considered. The tangents at the points where the incident lights I11 and I21 are reflected by the logarithmic spiral Sp are t1 and t2, and the normals thereof are S1 and S2. It is assumed that the incident light I11 is reflected at the point of the radius r1 of the logarithmic spiral Sp, and the incident light I21 is reflected at the point of the radius r2 of the logarithmic spiral Sp (however, r1 ≠ r2). At this time, due to the nature of the logarithmic spiral Sp, the angle formed by the incident light I11 and the tangent line t1 and the angle formed by the incident light I21 and the tangent line t2 are both b. Therefore, the incident angle φ formed by the incident light I11 and the normal line S1 and the incident angle φ formed by the incident light I21 and the normal line S2 have the same angle. Further, the reflection angle φ formed by the reflected light I12 and the normal line S1 and the reflection angle φ formed by the reflected light I22 and the normal line S2 also have the same angle. When φ and b are angles expressed by the radian method, the relationship between φ and b is as shown in the following equation (3).

From the above, it can be seen that the incident light I11 heading from the outside of the logarithmic spiral Sp toward the origin O is reflected at the same reflection angle φ regardless of which point of the logarithmic spiral Sp is reflected. Therefore, when the logarithmic spiral Sp is rotated around the origin O, the point where the incident light I11 reflected on the logarithmic spiral Sp is reflected changes, but the direction in which the reflected light I12 is reflected does not change, so that the reflected light I12 is translated. Moving.

In order to utilize this property, the logarithmic spiral reflector 361 of the present embodiment has at least a part of the reflecting surface as a logarithmic spiral whose origin O is the rotation axis w in the cross section perpendicular to the rotation axis w. As a result, by rotating the logarithmic spiral reflector 361 with the rotation axis w, it is possible to perform scanning such that the light reflected by the reflecting surface 361a is translated.

Returning to FIG. 11 again, the parallel scanning by the reflected light in the logarithmic spiral reflector 361 will be described. The light reflected by the logarithmic spiral reflector 361 is incident on either the planar reflector 362 or the planar reflector 364 and reflected depending on the angle of the logarithmic spiral reflector 361. The light reflected by the planar reflector 362 is reflected by the planar reflector 363 and emitted to the outside of the distance measuring device 300. The injection direction at this time is the positive direction of the z-axis. The light reflected by the planar reflector 364 is reflected by the planar reflector 365 and emitted to the outside of the distance measuring device 300. The injection direction at this time is the negative direction of the z-axis.

When the logarithmic spiral reflector 361 is rotated clockwise as shown in FIG. 11, the light emitted from the distance measuring device 300 moves in parallel from the optical path L5 toward the optical path L6. When the logarithmic spiral reflector 361 is further rotated while the emitted light is in the optical path L6, the emitted light changes discontinuously from the optical path L6 to the optical path L7. After that, the emitted light moves in parallel from the optical path L7 toward the optical path L8, and discontinuously changes from the optical path L8 to the optical path L5. As described above, the distance measuring device 300 of the present embodiment can alternately scan different directions of the z-axis in the positive direction and the negative direction.

As a result, the ranging device 300 of the present embodiment can perform scanning by translating the emitted light in the x-axis direction. Further, as in the first embodiment, the distance measuring device 300 of the present embodiment can also perform scanning in which the emitted light is translated in the y-axis direction. Therefore, in addition to obtaining the same effect as that of the first embodiment, the distance measuring device 300 of the present embodiment combines two-dimensional scanning in the x-axis direction and the y-axis direction and distance measurement in the z-axis direction. As a result, it functions as a three-dimensional sensor device capable of acquiring three-dimensional position information. Further, since the distance measuring device 300 of the present embodiment can alternately scan in the positive direction and the negative direction of the z-axis, one range measuring device 300 performs distance measurement in two different directions. be able to.

[Fifth Embodiment]
Next, as a fifth embodiment of the present invention, a configuration example of a distance measuring device including two optical systems will be described. The description of the elements common to the above-described embodiments will be omitted or simplified.

FIG. 14 is a schematic view showing a structure of the distance measuring device 400 according to the fifth embodiment as viewed from the front. FIG. 15 is a schematic view showing the structure of the distance measuring device 400 as viewed from above. The structure of the ranging device 400 will be described with reference to these figures.

The distance measuring device 400 includes a first optical system 401 and a second optical system 402. The first optical system 401 includes a sensor unit 130, a parabolic reflector 140, and a planar reflector 160. Since the first optical system 401 is the same as the distance measuring device 100 of the first embodiment, the description thereof will be omitted. The top view of the first optical system 401 is the same as that in FIG.

The second optical system 402 includes a parabolic reflector 440 and a planar reflector 460. The parabolic reflector 440 has a reflecting surface 440a. The parabolic reflector 440 may be referred to as a second reflector, and the planar reflector 460 may be referred to as a fourth reflector. Further, the reflecting surface 440a may be referred to as a second reflecting surface. The reflection surface 440a forms a parabola whose focal point is a point on the rotation axis u in a cross section perpendicular to the rotation axis u (xy plane in FIG. 14). The parabolic reflector 440 has a structure that is line-symmetrical with the parabolic reflector 140. Further, the planar reflecting mirror 460 has a structure that is line-symmetrical with the planar reflecting mirror 160. The parabolic reflector 140 and the parabolic reflector 440 are arranged at positions symmetrical with respect to the axis of the parabola. Further, the plane reflector 160 and the plane reflector 460 are arranged at positions symmetrical with respect to the axis of the parabola. The structure of the housing for storing each element of the second optical system 402 may be, for example, the housing shown in FIG. 2 of the first embodiment inverted in the y direction.

When light is emitted from the sensor unit 130 in the lower left direction in the drawing, it is incident on the reflecting surface 440a. The light reflected by the reflecting surface 440a is parallel to the axis of the parabola like the optical paths L9 and L10. The light reflected by the reflecting surface 440a is emitted to the outside of the second optical system 402 as shown in FIG.

Here, both the reflecting surface 140a of the parabolic reflecting mirror 140 and the reflecting surface 440a of the parabolic reflecting mirror 440 are provided so as to exclude the apex of the parabola. This configuration corresponds to the optical path diagram shown in FIG. As a result, as described in the explanations of FIGS. 5 to 7, the reflected light at the apex of the parabola is not re-entered into the sensor unit 130, so that the reduction in detection accuracy can be suppressed. Therefore, also in the present embodiment, as in the first embodiment, it is possible to provide the distance measuring device 400 with improved detection accuracy. Further, in the present embodiment, the scanning range of the emitted light can be widened by using two optical systems.

[Sixth Embodiment]
Next, as a sixth embodiment of the present invention, a configuration example of a distance measuring device including a logarithmic spiral reflector and two parabolic reflectors will be described. The description of the elements common to the above-described embodiments will be omitted or simplified.

FIG. 16 is a schematic view showing a structure of the distance measuring device 301 according to the sixth embodiment as viewed from the front. FIG. 17 is a schematic view showing the structure of the distance measuring device 301 as viewed from above. The range-finding device 301 of the present embodiment replaces the parabolic reflector 340 with the parabolic reflector 140 and the parabolic reflector 440 of the fifth embodiment in the range-finding device 300 of the fourth embodiment. The same effect as that of the fourth embodiment can be obtained in this embodiment as well. Further, in the present embodiment, the structure of the parabolic reflector is simplified as compared with the case of the fourth embodiment.

[7th Embodiment]
Next, as a seventh embodiment of the present invention, a configuration example of an article display shelf provided with the distance measuring device 400 of the fifth embodiment will be described. The description of the elements common to the above-described embodiments will be omitted or simplified.

FIG. 18 is a schematic perspective view of the article display shelf 500 according to the seventh embodiment. FIG. 19 is a schematic side view of the article display shelf 500. The structure of the article display shelf 500 will be described with reference to each other.

The article display shelf 500 is a shelf for displaying articles 540, and may be, for example, a product display shelf installed in a commercial facility. The article display shelf 500 includes a shelf 510 and two ranging devices 400. The two ranging devices 400 are arranged on the side surface of the shelf 510. The shelves 510 include four display units 520 separated by shelf boards 530. Goods and other goods 540 are displayed in the display section 520. Further, the display portion 520 has an opening portion 570 for loading and unloading the article 540. The number of the distance measuring device 400 and the display unit 520 is not limited to the one shown in the figure, and may be a plurality or a singular number.

The distance measuring device 400 is a device including the first optical system 401 and the second optical system 402 described in the fifth embodiment. Light emitted in the positive direction of the z-axis through the first optical system 401 or the second optical system 402 passes across the front surface of the opening 570 of the display portion 520. As a result, a detection region 550 by the ranging device 400 is formed on the front surface of the opening 570 of the display portion 520. When the customer 560 removes the article 540 from the display unit 520, or returns the removed article 540 to the display unit 520, the hands of the article 540 and the customer 560 pass through the detection area 550. The distance measuring device 400 detects the loading and unloading of the article 540 by detecting the hand of the article 540 or the customer 560 passing through the detection area 550. When a plurality of articles 540 can be arranged in the display unit 520, the distance measuring device 400 identifies the article 540 that has been taken in and out by detecting the position where the article was taken in and out or the shape of the article 540 that was taken in and out. You may.

The article display shelf 500 of the present embodiment is provided with the distance measuring device 400, so that it is possible to detect the loading and unloading of the displayed article 540. This function can be used, for example, for product management, theft prevention, and the like. Further, as described above, since the distance measuring device 400 has a small thickness in the light emitting direction, it can be installed in a narrow place on the side surface of the article display shelf 500. Thereby, the size of the entire article display shelf 500 can be reduced.

Although not essential, it is desirable that the position of the shelf plate 530 in the y-axis direction is between the first optical system 401 and the second optical system 402 as shown in FIG. In the distance measuring device 400 of the fifth embodiment, the space between the first optical system 401 and the second optical system 402 is a dead area, and by arranging the shelf board 530 in this dead area, the dead area is created. It can be substantially reduced.

In other words, the configuration in which the shelf board 530 is arranged in the dead area described above can be described as follows. In FIG. 18, the first and third display units 520 from the top are referred to as the first display unit, and the second and fourth display units 520 from the top are referred to as the second display unit. Further, the opening 570 corresponding to the first display portion is referred to as a first opening, and the opening 570 corresponding to the second display portion is referred to as a second opening. At this time, as shown in FIG. 18, the light emitted from the first optical system 401 is arranged so as to cross the front surface of the first opening, and the light emitted from the second optical system 402 is emitted. , Arranged across the front of the second opening. In this case, the first display unit and the second display unit are separated from each other by the shelf board 530, and the positions of the shelf board 530 are the positions of the first optical system 401 and the second optical system 402. Corresponds to the dead zone between.

Although the distance measuring device 400 of the fifth embodiment is mentioned as an example of the distance measuring device installed on the article display shelf 500 of the present embodiment, the distance measuring device of another embodiment may be used.

[Eighth Embodiment]
Next, as an eighth embodiment of the present invention, a configuration example of an article display shelf in which the arrangement of the distance measuring device is changed with respect to the seventh embodiment will be described. The description of the elements common to the above-described embodiments will be omitted or simplified.

FIG. 20 is a front schematic view of the article display shelf 501 according to the eighth embodiment. The article display shelf 501 of the present embodiment includes a shelf 511 and four distance measuring devices 400a, 400b, 400c, and 400d arranged around the shelf 511. In the article display shelf 501 of the present embodiment, the arrangement of the distance measuring device is different from that of the seventh embodiment. The distance measuring device 400a is arranged on the left side surface of the shelf 511. The ranging device 400b is arranged on the right side surface of the shelf 511. The ranging device 400c is arranged on the upper surface of the shelf 511. The distance measuring device 400d is arranged on the lower surface of the shelf 511. The light emitted from each ranging device 400 passes across the front surface of the display unit 521. As a result, a detection region by the distance measuring device 400 is formed on the front surface of the opening 571 of the display portion 521, and the distance measuring device 400 can detect the loading and unloading of the article 540.

In the present embodiment, the distance measuring device 400a (first sensor device) emits light in the first direction which is the negative direction of the z-axis, and the distance measuring device 400b (second sensor device) emits light in the positive direction of the z-axis. Light is emitted in the second direction, which is the direction. That is, the distance measuring device 400a and the distance measuring device 400b emit light that is parallel to each other and in opposite directions. Similarly, the distance measuring device 400c and the distance measuring device 400d also emit light parallel to each other and in opposite directions. As a result, even in a situation where a plurality of customers 560 take in and out the article 540 at the same time, the light is less likely to be blocked by the article 540 and the like, and the detection accuracy is improved.

Further, the distance measuring devices 400a and 400b (first sensor device) emit light in the first direction which is the z-axis direction, and the distance measuring devices 400c and 400d (second sensor device) emit light in the y-axis direction. Since they emit light in a second direction, they emit light perpendicular to each other. As a result, it is possible to detect the place where the customer 560 puts in and takes out the article 540 from two directions, and the detection accuracy is further improved.

[9th Embodiment]
Next, as a ninth embodiment of the present invention, a configuration example of an article display shelf in which the arrangement of the distance measuring device is changed with respect to the seventh embodiment will be described. The description of the elements common to the above-described embodiments will be omitted or simplified.

FIG. 21 is a schematic side view of the article display shelf 502 according to the ninth embodiment. In the article display shelf 502 of the present embodiment, the shape of the shelf 511 and the arrangement of the second optical system 402 are different from those in the seventh embodiment. In the shelf 511 of the present embodiment, the bottom shelf plate 531 protrudes toward the customer. In order to correspond to this, the second optical system 402 provided at the lowermost stage is provided at an angle with respect to the first optical system 401 at the upper stage so as to form an angle θ. As a result, the detection region 551 formed by the second optical system 402 provided in the lowermost stage forms an angle θ with respect to the detection region 550 formed by the first optical system 401 in the upper stage. As a result, the detection area can be arranged at an appropriate position even for shelves having different widths of the shelf boards for each stage. When the second optical system 402 is tilted and arranged, parallel scanning is possible by rotating the second optical system 402 around the rotation axis u of the sensor unit 130 in the first optical system 401. The detection area can be tilted while maintaining the optical arrangement.

The range of the angle θ is set to, for example, a range larger than 160 degrees and smaller than 180 degrees. This is because the first optical system 401 and the second optical system 402 have shapes that are vertically long in the x direction, so that the members may interfere with each other when the angle θ is 160 degrees or less.

[10th Embodiment]
Next, as a tenth embodiment of the present invention, a configuration example of an article display shelf provided with the distance measuring device 301 of the sixth embodiment will be described. The description of the elements common to the above-described embodiments will be omitted or simplified.

FIG. 22 is a schematic perspective view of the article display shelf 503 according to the tenth embodiment. The article display shelf 503 of the present embodiment includes shelves 510 and 512 and two ranging devices 301. The two ranging devices 301 are arranged between the side surface of the shelf 510 and the side surface of the shelf 512. Since the distance measuring device 301 of the sixth embodiment can emit light in two directions to form a detection region, the distance measuring device 301 detects the loading and unloading of the article 540 with respect to both the left and right shelves 510 and 512. It can be performed. As a result, for example, the number of distance measuring devices installed can be reduced as compared with the case where the distance measuring device 400 of the fifth embodiment is installed. The distance measuring device used for the article display shelf 503 of the present embodiment may be the distance measuring device 300 of the fourth embodiment.

The apparatus described in the above-described embodiment can also be configured as in the following 11th embodiment or 12th embodiment.

[11th Embodiment]
FIG. 23 is a front schematic diagram of the sensor device 600 according to the eleventh embodiment. The sensor device 600 includes a sensor unit 630, a first reflector 640, and a second reflector 660. The sensor unit 630 is a sensor unit that emits light and receives light reflected from an object, and is configured to be capable of scanning so as to rotate the direction of the emitted light around the first rotation axis u. Has been done. In the first reflecting mirror 640, at least a part of the reflecting surface 640a forms a parabola in a cross section perpendicular to the first rotation axis u. In the second reflecting mirror 660, at least a part of the reflecting surface 660a is a flat surface. The light emitted from the sensor unit 630 is reflected by the first reflecting mirror 640 and then reflected by the second reflecting mirror 660 to be emitted to the outside.

According to this embodiment, a sensor device having an improved degree of freedom in installation location is provided.

[12th Embodiment]
FIG. 24 is a functional block diagram of the sensor device 700 according to the twelfth embodiment. The sensor device 700 includes a sensor unit 730 and a first reflector 740. The sensor unit 730 is a sensor unit that emits light and receives light reflected from an object, and is configured to be capable of scanning to rotate the direction of the emitted light around a predetermined rotation axis u. ing. The first reflecting mirror 740 has a first reflecting surface 740a that reflects light emitted from the sensor unit 730, and at least a part of the first reflecting surface 740a is a parabola in a cross section perpendicular to the rotation axis u. Is doing. The first reflecting surface 740a is provided at a position other than the apex of the parabola.

According to this embodiment, a sensor device with improved detection accuracy is provided.

[Modification Embodiment]
It should be noted that the above-described embodiments are merely examples of embodiment of the present invention, and the technical scope of the present invention should not be construed in a limited manner by these. That is, the present invention can be implemented in various forms without departing from the technical idea or its main features. For example, an embodiment in which a partial configuration of any of the embodiments is added to another embodiment or replaced with a partial configuration of another embodiment is also an embodiment to which the present invention can be applied. Should be understood.

Some or all of the above embodiments may also be described, but not limited to:

(Appendix 1)
A sensor unit that emits light and receives light reflected from an object, and is configured to perform scanning that rotates the direction of the emitted light around a predetermined rotation axis. ,
A first reflecting mirror having a first reflecting surface that reflects light emitted from the sensor unit, and at least a part of the first reflecting surface forming a parabola in a cross section perpendicular to the rotation axis. When,
Equipped with
A sensor device characterized in that the first reflecting surface is provided at a position other than the apex of the parabola.

(Appendix 2)
A second reflection having a second reflection surface that reflects light emitted from the sensor unit, and in a cross section perpendicular to the axis of rotation, at least a part of the second reflection surface forms the parabola. With more mirrors
The sensor device according to Appendix 1, wherein the second reflecting surface is provided at a position other than the apex of the parabola.

(Appendix 3)
The sensor device according to Appendix 2, wherein the apex of the parabola is located between the first reflecting surface and the second reflecting surface in a cross section perpendicular to the axis of rotation.

(Appendix 4)
The sensor device according to Appendix 2 or 3, wherein the sensor unit is arranged in the vicinity of the focal point of the parabola formed by the first reflecting surface and the focal point of the parabola formed by the second reflecting surface.

(Appendix 5)
Item 1. The sensor device described.

(Appendix 6)
Item 2. The sensor device described.

(Appendix 7)
The sensor unit has an optical path of light emitted from the sensor unit reflected by the first reflecting mirror and light emitted from the sensor unit reflected by the second reflecting mirror. The sensor device according to Appendix 6, wherein the sensor device is arranged between the optical path and the optical path.

(Appendix 8)
Further equipped with a third reflecting mirror in which at least a part of the reflecting surface is a flat surface,
The light emitted from the sensor unit is reflected by the first reflecting mirror and then reflected by the third reflecting mirror, so that the light is emitted to the outside. The sensor device according to item 1.

(Appendix 9)
A third reflecting mirror in which at least a part of the reflecting surface is flat,
A fourth reflector whose at least part of the reflecting surface is flat,
Further prepare
The light emitted from the sensor unit is reflected by the first reflecting mirror or the second reflecting mirror according to the emission direction of the light, and then the light reflected by the first reflecting mirror is the said. It is characterized in that the light reflected by the third reflecting mirror is emitted to the outside, and the light reflected by the second reflecting mirror is emitted to the outside by being reflected by the fourth reflecting mirror. The sensor device according to any one of Supplementary note 2 to 7.

(Appendix 10)
A first optical system including the sensor unit, the first reflector, and the third reflector.
A second optical system including the second reflecting mirror and the fourth reflecting mirror,
The sensor device according to Appendix 9, further comprising.

(Appendix 11)
The sensor device according to any one of Supplementary note 1 to 10 and the sensor device.
The display section that displays goods and
Goods display shelves with.

(Appendix 12)
The display portion has an opening for loading and unloading the article.
The article display shelf according to Appendix 11, wherein the sensor device is arranged so that light emitted from the sensor device crosses the front surface of the opening.

(Appendix 13)
A plurality of the sensor devices including the first sensor device and the second sensor device are provided.
The first sensor device is arranged so that the light emitted from the first sensor device crosses the front surface of the opening in the first direction.
The second sensor device is characterized in that light emitted from the second sensor device is arranged so as to cross the front surface of the opening in a second direction different from the first direction. The article display shelf according to Appendix 12.

(Appendix 14)
The article display shelf according to Appendix 13, wherein the first direction and the second direction are parallel to each other and opposite to each other.

(Appendix 15)
The article display shelf according to Appendix 13, wherein the first direction and the second direction are perpendicular to each other.

(Appendix 16)
The sensor device according to Appendix 10 and
The first display section and the second display section for displaying goods,
Equipped with
The first display section and the second display section are separated from each other.
The first display portion has a first opening for loading and unloading the article.
The second display portion has a second opening for loading and unloading the article.
The first optical system is arranged so that the light reflected by the third reflecting mirror crosses the front surface of the first opening.
The second optical system is an article display shelf characterized in that the light reflected by the fourth reflecting mirror is arranged so as to cross the front surface of the second opening.

(Appendix 17)
The surface through which the light reflected by the third reflecting mirror passes and the surface through which the light reflected by the fourth reflecting mirror passes form an angle larger than 160 degrees and smaller than 180 degrees. The article display shelf according to Appendix 16 as a feature.

100 Distance measuring device 130 Sensor unit 140 Parabolic reflector

Claims (17)

A sensor unit that emits light and receives light reflected from an object, and is configured to perform scanning that rotates the direction of the emitted light around a predetermined rotation axis. ,
A first reflecting mirror having a first reflecting surface that reflects light emitted from the sensor unit, and at least a part of the first reflecting surface forming a parabola in a cross section perpendicular to the rotation axis. When,
Equipped with
The first reflecting surface is provided at a position other than the apex of the parabola .
The sensor unit includes a laser device that emits light and a photoelectric conversion element that receives light reflected from the object and converts it into an electric signal.
The laser device and the photoelectric conversion element are both sensor devices arranged in the vicinity of the focal point of the parabola formed by the first reflecting surface. A second reflection having a second reflection surface that reflects light emitted from the sensor unit, and in a cross section perpendicular to the axis of rotation, at least a part of the second reflection surface forms the parabola. With more mirrors
The sensor device according to claim 1, wherein the second reflecting surface is provided at a position other than the apex of the parabola. The sensor device according to claim 2, wherein the apex of the parabola is located between the first reflecting surface and the second reflecting surface in a cross section perpendicular to the rotation axis. The sensor device according to claim 2 or 3, wherein the sensor unit is arranged in the vicinity of the focal point of the parabola formed by the first reflecting surface and the focal point of the parabola formed by the second reflecting surface. One of claims 2 to 4, wherein the axis of rotation is arranged at a position passing through the focal point of the parabola formed by the first reflecting surface and the focal point of the parabola formed by the second reflecting surface. The sensor device described in. One of claims 2 to 5, wherein the light emitted from the sensor unit is reflected by the first reflecting mirror or the second reflecting mirror according to the emission direction of the light. The sensor device described in. The sensor unit has an optical path of light emitted from the sensor unit reflected by the first reflecting mirror and light emitted from the sensor unit reflected by the second reflecting mirror. The sensor device according to claim 6, wherein the sensor device is arranged between the optical path and the optical path. Further equipped with a third reflecting mirror in which at least a part of the reflecting surface is a flat surface,
Claims 1 to 7, wherein the light emitted from the sensor unit is reflected by the first reflecting mirror and then reflected by the third reflecting mirror to be emitted to the outside. The sensor device according to any one item. A third reflecting mirror in which at least a part of the reflecting surface is flat,
A fourth reflector whose at least part of the reflecting surface is flat,
Further prepare
The light emitted from the sensor unit is reflected by the first reflecting mirror or the second reflecting mirror according to the emission direction of the light, and then the light reflected by the first reflecting mirror is the said. It is characterized in that the light reflected by the third reflecting mirror is emitted to the outside, and the light reflected by the second reflecting mirror is emitted to the outside by being reflected by the fourth reflecting mirror. The sensor device according to any one of claims 2 to 7. A first optical system including the sensor unit, the first reflector, and the third reflector.
A second optical system including the second reflecting mirror and the fourth reflecting mirror,
9. The sensor device according to claim 9, further comprising. The sensor device according to any one of claims 1 to 10.
The display section that displays goods and
Goods display shelves with. The display portion has an opening for loading and unloading the article.
The article display shelf according to claim 11, wherein the sensor device is arranged so that light emitted from the sensor device crosses the front surface of the opening. A plurality of the sensor devices including the first sensor device and the second sensor device are provided.
The first sensor device is arranged so that the light emitted from the first sensor device crosses the front surface of the opening in the first direction.
The second sensor device is characterized in that light emitted from the second sensor device is arranged so as to cross the front surface of the opening in a second direction different from the first direction. The article display shelf according to claim 12. The article display shelf according to claim 13, wherein the first direction and the second direction are parallel to each other and opposite to each other. The article display shelf according to claim 13, wherein the first direction and the second direction are perpendicular to each other. The sensor device according to claim 10 and
The first display section and the second display section for displaying goods,
Equipped with
The first display section and the second display section are separated from each other.
The first display portion has a first opening for loading and unloading the article.
The second display portion has a second opening for loading and unloading the article.
The first optical system is arranged so that the light reflected by the third reflecting mirror crosses the front surface of the first opening.
The second optical system is an article display shelf characterized in that the light reflected by the fourth reflecting mirror is arranged so as to cross the front surface of the second opening. The surface through which the light reflected by the third reflecting mirror passes and the surface through which the light reflected by the fourth reflecting mirror passes form an angle larger than 160 degrees and smaller than 180 degrees. The article display shelf according to claim 16, which is characterized.

Images