JP6812776B2 - Distance measurement sensor - Google Patents

Description

The present invention relates to a distance measuring sensor that irradiates light and detects a distance to an object.

Conventionally, a technique has been used in which light is irradiated to a predetermined range set in advance, the light reflected by the object is acquired, and the distance to the object is detected. As a technique of this kind, for example, there is one described in Patent Document 1-3.

In Patent Document 1, one beam is converted into a plurality of beams, each converted beam is scanned at the same time, and reflections from a detection object are distinguished for each beam by a plurality of beam receiving means provided. The receiving position information detection device is disclosed. This position information detection device performs two-dimensional scanning on the scanning plane including the height direction in one scan, and the position of the detection object in the three-dimensional space based on the scanning position information and the distance information to the detection object. Is specified.

Patent Document 2 discloses an in-vehicle radar device including a polygon mirror having a plurality of light beam reflecting surfaces, each reflecting surface having a different tilt angle with respect to the rotation axis of the polygon mirror. This in-vehicle radar device scans the laser incident on the reflecting surface of the polygon mirror in the left-right direction by the rotation of the polygon mirror, and scans while shifting in the vertical direction each time the reflecting surface on which the laser light is incident is switched. Two-dimensional scanning is performed on the scanning plane.

Patent Document 3 irradiates a light beam in front of the vehicle, receives the reflected wave, generates information necessary for measuring the distance between the vehicle and the preceding vehicle located in front of the vehicle, and reduces the elevation angle of the light beam. An in-vehicle radar device that changes direction to detect a white line on a road surface or a traveling zone indicator line corresponding thereto and generates information necessary for lane keeping is disclosed. This in-vehicle radar device emits a horizontally scanned light beam in front of the vehicle, and when the light beam reaches a predetermined horizontal scanning angle directed to a white line on the road surface or a corresponding traveling zone indicator line. In addition, the light beam is refracted by an optical element such as a prism to change the elevation angle in the negative direction.

Japanese Unexamined Patent Publication No. 8-248133 Japanese Unexamined Patent Publication No. 2000-147124 Japanese Unexamined Patent Publication No. 2003-121546

In the technique described in Patent Document 1, since one beam is converted into a plurality of beams through a half mirror, the amount of light of each beam after conversion is reduced with respect to the original amount of light. Since the detection distance of the object is narrowed due to the decrease in the amount of light, and the receiving means (photodiode) is provided for each of a plurality of beams, this causes an increase in cost.

In the technique described in Patent Document 2, since the scanning angle in the horizontal direction depends on the allocation angle of each surface of the polygon mirror, it is not possible to scan at a wide angle on all the surfaces. In addition, since reflected light with a large light receiving angle with respect to the central axis connecting the center of the light receiving lens and the photodiode is not collected by the photodiode, it is necessary to provide a light receiving mirror on the upper part or the side portion to collect the light, which increases the cost. It becomes a factor.

Since the technique described in Patent Document 3 is premised on white line detection, the beam angle can be changed only at a specific location, and the vertical angle cannot be detected over a wide angle. Further, since the reflected light of the laser irradiated in the negative direction by refraction has a large light receiving angle, the amount of light collected by the light receiving element is small, and the detection distance may be shortened or may not be detected properly.

Therefore, there is a need for a distance measuring sensor that can detect the distance to an object over a wide range and can be realized at low cost.

The characteristic configuration of the distance measuring sensor according to the present invention is a light projecting unit provided with a light source that irradiates light and a light projecting lens that converts the light emitted from the light source into parallel light, and an incident light from the light projecting unit. A light projection mirror that changes the traveling direction of the parallel light so as to follow a predetermined first direction according to rotation around a predetermined rotation axis, and the rotation axis as an axis. A translucent member having a cylindrical shape that changes the traveling direction of the parallel light reflected by the projection mirror and changes the traveling direction of the reflected light reflected by the parallel light projected to the surroundings. And a light receiving portion for detecting the reflected light whose traveling direction is changed by the translucent member, the translucent member is a surface formed along the circumferential direction of the translucent member. The present invention is provided with a plurality of projection surfaces arranged so that the angles of the surfaces adjacent to each other along the circumferential direction with respect to the axial center are different from each other, and are provided inside the translucent member in the radial direction. When the light projecting prism portion that projects the parallel light incident from the light projecting mirror from the projection surface along the second direction intersecting the first direction and the translucent member are viewed from the outside in the radial direction. The circumferential direction of the translucent member on the outer peripheral surface of the translucent member so that the angle of the outer peripheral surface of the translucent member with respect to the axial center is the same as the angle of the projection surface with respect to the axial center. It has a plurality of incident surfaces formed along the above, and the reflected light travels according to the incident of the reflected light reflected by the parallel light projected from the projection prism portion on the incident surface. The point is that it is provided with a light receiving prism portion that changes the direction.

With such a characteristic configuration, it is possible to irradiate by bending in the second direction at a predetermined angle within a range of 360 degrees (horizontal) using one parallel light (light beam). Therefore, it is possible to irradiate a light beam over a wide range without using a complicated polygon mirror. Further, since one light beam is irradiated without being dispersed, the amount of light is not reduced and the detection distance is not narrowed. Further, since the light receiving prism portion is tilted at the same angle as the light emitting prism portion, the reflected light from the object to be detected by the distance measuring sensor is refracted by the light receiving prism portion for light reception. It is incident on the mirror. As a result, the reflected light can be incident on the light receiving mirror at the same angle regardless of the light beam irradiated at any angle, so that it is not necessary to provide a plurality of light receiving parts and the light is received by one light receiving part. It becomes possible. Therefore, the distance measuring sensor can be realized at low cost. Further, by changing the ratio of the tilted area of the light receiving prism portion, it is possible to control the increase or decrease of the light receiving amount in the predetermined direction, so that the detection range in the predetermined direction can be widened or narrowed. ..

Further, the light projecting prism portion is formed in a first axial region which is a part of the translucent member from one end in the axial direction to the other end in the axial direction, and the light receiving light is received. It is preferable that the prism portion is formed in a second axial region other than the first axial region from the end on one axial side of the translucent member to the other end in the axial direction. is there.

With such a configuration, it is possible to prevent the light receiving prisms having different angles from being adjacent to each other on the incident path of the reflected light reflected by the object with respect to the light receiving prism, so that the reflected light is for receiving light. It is possible to prevent the light amount from being attenuated by being incident on the light receiving prism portions having different angles before being incident on the prism portion. Therefore, it is possible to prevent the amount of reflected light (light amount) incident on the light receiving prism portion from being reduced, and to improve the light receiving efficiency.

Further, it is preferable that the light projecting prism portion is formed on the outer peripheral surface of the translucent member.

With such a configuration, it is possible to easily form a light projecting prism portion capable of irradiating parallel light in a desired direction on the translucent member. Therefore, it can be configured at low cost.

Further, a light receiving mirror for reflecting the reflected light whose traveling direction has been changed by the light receiving prism portion toward the light receiving portion is provided, and the light receiving mirror is integrally rotated with the light projecting mirror. It is preferable that it is configured in.

With such a configuration, the power for rotating the light projecting mirror and the power for rotating the light receiving mirror can be shared. Therefore, it is possible to realize low cost and miniaturization.

Further, the light projecting prism portion may be configured to include a plane formed along the circumferential direction of the translucent member.

With such a configuration, the projection prism portion can be easily formed.

It is a block diagram which shows the structure of the distance measuring sensor. It is a figure which showed the arrangement of a light emitting part and a light receiving part. It is a side view of the translucent member. It is explanatory drawing of the prism part for floodlight. It is a figure which showed the translucent member which concerns on other embodiment. It is a figure which showed the translucent member which concerns on other embodiment. It is a figure which showed the translucent member which concerns on other embodiment. It is a figure which showed the translucent member which concerns on other embodiment. It is a figure which showed the translucent member which concerns on other embodiment. It is a schematic diagram of the ranging sensor which concerns on other embodiments.

The distance measuring sensor according to the present invention is configured to be able to detect the distance to an object over a wide range with an inexpensive configuration. Hereinafter, the ranging sensor 1 of the present embodiment will be described. FIG. 1 is a block diagram schematically showing the configuration of the distance measuring sensor 1 of the present embodiment. Further, FIG. 2 is a diagram showing the arrangement of the light emitting unit 11 and the light receiving unit 51. As shown in FIGS. 1 and 2, the distance measuring sensor 1 includes a control unit 2, a translucent member 3, a light projecting unit 11, a light projecting mirror 15, a light receiving mirror 45, a light receiving unit 51, and a motor 60. It includes an encoder 61.

The light projecting unit 11 is provided with a light source 12 and a light projecting lens 13. The light source 12 is configured by using, for example, a laser or an LED, and irradiates the surroundings with light. The light emitted from the light source 12 is incident on the projection lens 13 described later. A control signal is transmitted from the control unit 2 and power is supplied to the light source 12. The light source 12 is driven by these control signals and a power source, and irradiates the surroundings with light.

The projectile lens 13 converts the light emitted from the light source 12 into parallel light. The light emitted from the light source 12 spreads in a predetermined range and travels. The floodlight lens 13 converts such light into parallel light traveling along a predetermined direction. This makes it possible to irradiate the light from the light source 12 only in a predetermined direction. The parallel light from the light projecting lens 13 is changed in the traveling direction and is irradiated to the outside of the distance measuring sensor 1. In the following, the parallel light emitted from the projection lens 13 will be referred to as a “projection beam” as necessary.

The light projecting mirror 15 changes the traveling direction of the parallel light incident from the light projecting unit 11 as the parallel light so as to follow the predetermined first direction according to the rotation around the predetermined rotation axis X. .. The floodlight mirror 15 is configured to have a mirror surface that reflects light. Therefore, the light projecting mirror 15 reflects the parallel light incident from the light projecting unit 11 as the parallel light. Further, the floodlight mirror 15 is rotated about the rotation axis X by a drive signal from the control unit 2. Therefore, the parallel light from the light projecting unit 11 is reflected as parallel light in the first direction (horizontal direction in the present embodiment) corresponding to the radial direction of the rotation axis X.

The translucent member 3 has a cylindrical shape centered on the rotation axis X (see FIG. 3), changes the traveling direction of the parallel light reflected by the light projecting mirror 15, and is projected to the surroundings in parallel. The direction of travel of the reflected light that is reflected by the light hitting the object is changed. The rotation axis X is a rotation axis when the floodlight mirror 15 rotates. Therefore, the translucent member 3 is configured on the coaxial center with the rotation axis X of the light projecting mirror 15. The parallel light is light whose traveling direction is changed by the projection mirror 15. This parallel light is projected around the ranging sensor 1. When the parallel light projected around the distance measuring sensor 1 hits an object, it is reflected and returned to the distance measuring sensor 1. Although the details will be described later, the translucent member 3 changes the traveling direction when the parallel light and the reflected light are transmitted. Therefore, the translucent member 3 is formed in a cylindrical shape by using a material capable of transmitting at least parallel light and reflected light.

The translucent member 3 has a light emitting prism portion 21 and a light receiving prism portion 31. The light projecting prism portion 21 is provided at a position where the light projecting beam is transmitted in the housing of the distance measuring sensor 1 at a predetermined angle, and the light projecting beam is refracted according to this angle. Is applied to the periphery of the ranging sensor 1. The light projecting prism portion 21 constitutes a housing window 70 as a window portion formed in the housing of the distance measuring sensor 1. The configuration of the projection prism portion 21 will be described later.

When the light projecting beam emitted from the light projecting prism unit 21 hits an object existing around the distance measuring sensor 1, it is reflected and becomes reflected light. This reflected light is acquired by the ranging sensor 1 via the light receiving prism portion 31. The light receiving prism portion 31 is provided at a position where the reflected light is transmitted at a predetermined angle, and the traveling direction of the reflected light is changed by refracting the reflected light according to this angle. In the present embodiment, the traveling direction of the reflected light is changed so as to be directed to the light receiving mirror 45 described later. The light receiving prism portion 31 constitutes a housing window 70 as a window portion formed in the housing of the distance measuring sensor 1 in the same manner as the light emitting prism portion 21 described above. The configuration of the light receiving prism portion 31 will be described later.

The light receiving mirror 45 reflects the reflected light whose traveling direction has been changed by the light receiving prism portion 31 toward the light receiving portion 51 described later. The light receiving mirror 45 is configured to have a mirror surface that reflects light, similarly to the light projecting mirror 15. Further, in the present embodiment, the light receiving mirror 45 is configured to rotate integrally with the light projecting mirror 15. Therefore, in the light receiving mirror 45, the rotation axis of the light projecting mirror 15 is coaxial. The reflected light from the light receiving prism portion 31 is reflected along the axial direction of the rotation axis X according to the rotation of the light receiving mirror 45.

The light receiving unit 51 has a light receiving lens 52 and a light receiving sensor 53. The light receiving lens 52 is provided between the light receiving mirror 45 and the light receiving sensor 53, and collects the reflected light reflected by the light receiving mirror 45 on the detection surface of the light receiving sensor 53. The light receiving sensor 53 detects the reflected light whose traveling direction is changed by the translucent member 3. In the present embodiment, the reflected light whose traveling direction is changed by the light receiving prism portion 31 as described above is collected by the light receiving lens 52. Therefore, the light receiving sensor 53 is arranged at the focal position of the light receiving lens 52, and detects the reflected light whose traveling direction is changed by the light receiving prism portion 31 at the focal position. Since the detection of light by the light receiving sensor 53 is known, the description thereof will be omitted. When the light receiving sensor 53 detects the reflected light, the light receiving unit 51 transmits the detection result to the control unit 2.

The control unit 2 calculates the distance from the distance measuring sensor 1 to the object using the transmitted detection result. Specifically, the detection result from the light receiving unit 51 and the information indicating that the light projecting unit 11 has irradiated the light are also transmitted to the control unit 2. The control unit 2 calculates the time from when the light projecting unit 11 irradiates the light until the light receiving sensor 53 receives the light, and the distance measuring sensor 1 is calculated by multiplying the speed of light by 1/2 of the time. Calculate the distance from to the object. Of course, it is also possible to correct the delay time required for signal processing of each functional unit for the above time. The control unit 2 controls the motor 60 that rotates the light projecting mirror 15 and the light receiving mirror 45, and acquires the detection result of the rotation angle of the motor 60 from the encoder 61. The control unit 2 controls the rotation of the motor 60 based on the detection result from the encoder 61.

Next, the configurations of the light emitting prism portion 21 and the light receiving prism portion 31 will be described. FIG. 3 is a side view of the translucent member 3. As described above, the translucent member 3 includes a light emitting prism portion 21 and a light receiving prism portion 31, and is provided in the housing window 70 of the distance measuring sensor 1.

In the present embodiment, as described above, the translucent member 3 is formed in a cylindrical shape centered on the rotation axis X of the light projecting mirror 15 and the light receiving mirror 45. The light projecting prism portion 21 is composed of a surface formed along the circumferential direction of such a cylindrical translucent member 3. The "plane formed along the circumferential direction of the cylindrical translucent member 3" means that a plurality of plane surfaces are formed along the circumferential direction of the translucent member 3. In the present embodiment, the light projecting prism portion 21 having these plane surfaces is formed on the outer peripheral surface of the translucent member 3 over the entire circumference. In this case, these plurality of planes divide the translucent member 3 into several degrees (for example, 3 to 5 degrees) along the circumferential direction when viewed from the outside in the axial direction so that the outer peripheral surfaces thereof are flat. It is formed. For this reason, it is preferable to configure each plane so that the lengths along the circumferential direction are equal to each other. Of course, the lengths along the circumferential direction of each plane need not be evenly configured. In the present embodiment, a flat surface is given as an example of "a surface formed along the circumferential direction of the cylindrical translucent member 3", but the surface is not limited to a flat surface, and may be, for example, a cylindrical surface or a conical surface. good.

Further, the projection prism portion 21 has a plurality of projection planes arranged so that the angles of the planes adjacent to each other along the circumferential direction with respect to the axial center are different from each other. The "angle with respect to the axis" means the angle difference between the radial direction orthogonal to the axis and the direction of the normal vector of each of the plurality of planes described above. In the present embodiment, the plane of the light projecting prism portion 21 is a surface facing the radial direction of the translucent member 3 (hereinafter referred to as “A surface”), and is above the radial direction of the translucent member 3. It is assumed that there is a surface facing the surface (hereinafter referred to as “B surface”) and a surface facing downward with respect to the radial direction of the translucent member 3 (hereinafter referred to as “C surface”).

FIG. 4 is an explanatory view of the projection surface of the projection prism portion 21. # 01 of FIG. 4 shows a perspective view of the translucent member 3. Further, # 02 shows the side view A of the part with the alternate long and short dash line in # 01, and # 03 shows the side view B of the part with the dashed line in # 01. In 03, the C plane, which is a side view of the portion with the alternate long and short dash line in # 01, is shown. For ease of understanding, in FIG. 3, the A surface, the B surface, and the C surface of the light projecting prism portion 21 are shown in the same color. As shown in FIGS. 3 and 4, the planes of the light projecting prism portion 21 are such that the A surfaces are not adjacent to each other and the B surfaces are not adjacent to each other along the circumferential direction. The C-planes are configured so that they are not adjacent to each other. In the present embodiment, as shown in FIGS. 3 and 4, the projection prism portion 21 is configured such that "plane A, plane B, plane C" repeats along the circumferential direction.

The light projecting prism portion 21 refracts the parallel light incident from the light projecting mirror 15 provided inside the translucent member 3 in the radial direction from the projection surface along the second direction intersecting the first direction. Project. That is, the plurality of planes repeatedly arranged as described above each form a projection surface, and parallel light reflected by the projection mirror 15 is incident from the inside in the radial direction along the direction in which the projection surface faces. And refract it to project parallel light. As a result, the light projecting prism portion 21 can project the parallel light incident from the light projecting mirror 15 at an angle in the vertical direction with respect to the horizontal direction.

Such a light projecting prism portion 21 is formed in the first axial region M which is a part of the translucent member 3 from the end on one side in the axial direction to the end on the other side in the axial direction. .. That is, as shown in FIG. 3, assuming that the axial length of the translucent member 3 is L, the light projecting prism portion 21 is a part of the axial length L of the translucent member 3. It is formed in the first axial region M.

On the other hand, in the light receiving prism portion 31, the angle of the outer peripheral surface of the translucent member 3 with respect to the axial center when the translucent member 3 is viewed from the outside in the radial direction is the same as the angle of the projection surface with respect to the axial center. As described above, the outer peripheral surface of the translucent member 3 has a plurality of incident surfaces formed along the circumferential direction of the translucent member 3. The "angle of the outer peripheral surface of the translucent member 3 with respect to the axial center when the translucent member 3 is viewed from the outside in the radial direction" is the axial center of the translucent member 3 in the side view of the translucent member 3. And the angle difference from the outer peripheral surface of the translucent member 3. In this embodiment, the projection plane corresponds to the A plane, the B plane, and the C plane. Therefore, the "angle of the projection surface with respect to the axis" corresponds to the angle θ2 of the B surface with respect to the axis and the angle θ3 of the C surface with respect to the axis, assuming that the angle θ1 of the A surface is parallel to the axis. ..

Therefore, in the light receiving prism portion 31, the angle difference between the axial center of the translucent member 3 and the outer peripheral surface of the translucent member 3 in the side view of the translucent member 3 is the angle of the A surface with respect to the axial center. It is formed on the outer peripheral surface of the translucent member 3 so as to have the same angle as θ1, the angle θ2 of the B surface with respect to the axis, and the angle θ3 of the C surface with respect to the axis. Further, in the present embodiment, the light receiving prism portion 31 has an A surface with respect to the axis so that the angle difference from the outer peripheral surface of the translucent member 3 is uniform over the circumferential direction of the translucent member 3. The first outer peripheral portion 71 formed at the angle θ1 of the above, the second outer peripheral portion 72 formed at the angle θ2 of the B surface with respect to the axial center, and the third outer peripheral portion 73 formed at the angle θ3 of the C surface with respect to the axial center. Will be done.

Further, in the light receiving prism portion 31, the first outer peripheral portion 71, the second outer peripheral portion 72, and the third outer peripheral portion 73 are not adjacent to the outer peripheral portion having the same angle, that is, the first outer peripheral portion 71 is A third outer peripheral portion 72 is adjacent to one or both of the first outer peripheral portion 71 and the third outer peripheral portion 73 so as to be adjacent to one or both of the second outer peripheral portion 72 and the third outer peripheral portion 73. The outer peripheral portion 73 is arranged so as to be adjacent to one or both of the first outer peripheral portion 71 and the second outer peripheral portion 72, and the first outer peripheral portion 71, the second outer peripheral portion 72, and the third outer peripheral portion 73 are the reflections described above. It constitutes an incident surface on which light is incident.

The light receiving prism unit 31 changes the traveling direction of the reflected light according to the incident surface of the reflected light reflected by the parallel light projected from the light projecting prism unit 21 hitting the object. That is, as described above, the reflected light is incident on the first outer peripheral portion 71, the second outer peripheral portion 72, and the third outer peripheral portion 73, respectively, and the traveling direction of the reflected light in the direction toward the light receiving mirror 45 due to refraction. Is changed.

Here, as shown in FIG. 3, assuming that the axial length of the translucent member 3 is L, the light projecting prism portion 21 is a part of the axial length L of the translucent member 3. Although the light receiving prism portion 31 is formed in a certain first axial direction region M, the light receiving prism portion 31 is formed in the first axial direction region from the end portion on one side in the axial direction of the translucent member 3 to the end portion on the other side in the axial direction. It is formed in the second axial region N other than M. In the present embodiment, as shown in FIG. 3, the light projecting prism portion 21 is formed at the central portion in the axial direction of the translucent member 3, but the first light projecting prism portion 21 is formed on both outer sides in the axial direction. The outer peripheral portion 71 is formed. Therefore, the first outer peripheral portion 71 is arranged in a state of being divided by the light projecting prism portion 21. A second outer peripheral portion 72 is formed on one axially outer side of the first outer peripheral portion 71, and a third outer peripheral portion 73 is formed on the other axial outer side of the first outer peripheral portion 71.

By providing the light projecting prism portion 21 in the translucent member 3 configured as described above at a predetermined position in the distance measuring sensor 1, the light projecting prism portion 21 is projected according to the angle of the projection surface. It is possible to refract the parallel light reflected by the light mirror 15 and project the parallel light around the distance measuring sensor 1. Further, by inclining the portion of the ranging sensor 1 where the light projecting prism portion 21 is not provided at the same angle as the angle of the light projecting prism portion 21, parallel projection is performed through the light projecting prism portion 21. When the reflected light reflected by the light hits the object is refracted and the axis of the translucent member 3 is arranged along the vertical direction, the light can be incident on the light receiving mirror 45 in the horizontal direction. Therefore, the reflected light from any direction can be received by one light receiving sensor 53.

The translucent member 3 may be arranged inside the housing window 70 or may be arranged outside. Further, it is preferable that the translucent member 3 is integrally formed of the same material as the housing window 70.

[Other Embodiments]
In the above embodiment, as shown in FIG. 3, in the light receiving prism portion 31, the first outer peripheral portion 71 is formed on both outer sides of the light emitting prism portion 21 in the axial direction, and one shaft of the first outer peripheral portion 71 is formed. It has been described that the second outer peripheral portion 72 is formed on the outer side in the direction, and the third outer peripheral portion 73 is formed on the other axial outer side of the first outer peripheral portion 71. However, as shown in FIG. 5, the first outer peripheral portion 71, the second outer peripheral portion 72, and the third outer peripheral portion 73 are formed on one side in the axial direction of the light projecting prism portion 21, and the light projecting prism portion 21 is formed. It is also possible to form a first outer peripheral portion 71, a second outer peripheral portion 72, and a third outer peripheral portion 73 on the other side in the axial direction of the above, and as shown in FIG. 6, for light projection. A plurality of sets of a first outer peripheral portion 71, a second outer peripheral portion 72, and a third outer peripheral portion 73 are formed on one side in the axial direction of the prism portion 21, and a first outer peripheral portion is also formed on the other side in the axial direction of the projection prism portion 21. It is also possible to form a plurality of sets of 71, the second outer peripheral portion 72, and the third outer peripheral portion 73. With such a configuration, it is possible to reduce the influence of the light receiving area due to the shape of the light receiving mirror 45 and to make the light receiving amount uniform. Further, although not shown, the numbers (divisions) of the first outer peripheral portion 71, the second outer peripheral portion 72, and the third outer peripheral portion 73 are made uneven so as to strongly receive the reflected light from a specific angle. By setting this, it is possible to control the detection distance of the distance measuring sensor 1.

In the above embodiment, the light projecting prism portion 21 has been described with an example of being arranged at the axial center portion of the translucent member 3, but as shown in FIG. 7, for example, the light projecting prism portion 21 has been described. The position of is also possible to be arranged at a position different from the axial central portion of the translucent member 3 (for example, a position on the axial end side side) according to the projection position of the parallel light.

Further, for example, as shown in FIG. 8, the light receiving prism portion 31 can be formed so as to be divided along the axial direction. Further, as shown in FIG. 9, the light emitting prism portion 21 and the light receiving prism portion 31 can be formed on the inner peripheral surface of the translucent member 3.

Further, as shown in FIG. 10, by changing the position of the light projecting unit 11 and providing the fixed mirror 16, the light projecting mirror 15 and the light receiving mirror 45 can be shared. Therefore, the distance measuring sensor 1 can be miniaturized.

In the above embodiment, it has been described that the light receiving mirror 45 is configured to rotate integrally with the light projecting mirror 15, but the light receiving mirror 45 is rotated separately from the light projecting mirror 15. It is also possible to configure in.

The present invention can be used in a ranging sensor that irradiates light to detect the distance to an object.

1: Distance measuring sensor 3: Translucent member 11: Light emitting part 12: Light source 13: Light source lens 15: Light projecting mirror 21: Light emitting prism part 31: Light receiving prism part 45: Light receiving mirror M: 1st axial region N: 2nd axial region

Claims (5)

A light projecting unit provided with a light source that irradiates light and a light projecting lens that converts the light emitted from the light source into parallel light.
A light projecting mirror that changes the traveling direction of the parallel light incident from the light projecting unit with the parallel light so as to follow a predetermined first direction according to rotation around a predetermined rotation axis.
It has a cylindrical shape with the rotation axis as the axis, changes the traveling direction of the parallel light reflected by the projection mirror, and advances the reflected light reflected by the parallel light projected to the surroundings. A translucent member that changes direction,
A light receiving unit for detecting the reflected light whose traveling direction has been changed by the translucent member is provided.
The translucent member is a surface formed along the circumferential direction of the translucent member, and is arranged so that the angles of the surfaces adjacent to each other along the circumferential direction with respect to the axial center are different from each other. From the projection surface along a second direction that intersects the first direction with the parallel light incident from the projection mirror provided on the inside in the radial direction of the translucent member. The angle between the projection prism portion to be projected and the outer peripheral surface of the translucent member with respect to the axial center when the translucent member is viewed from the outside in the radial direction is the same as the angle of the projection surface with respect to the axial center. The outer peripheral surface of the translucent member has a plurality of incident surfaces formed along the circumferential direction of the translucent member so as to be at an angle, and the parallel light projected from the light projection prism portion is emitted. A distance measuring sensor including a light receiving prism portion that changes the traveling direction of the reflected light according to the incident light reflected on the object onto the incident surface. The light projecting prism portion is formed in a first axial region which is a part of the translucent member from one end in the axial direction to the other end in the axial direction.
The light receiving prism portion is formed in a second axial region other than the first axial region from an end portion on one side in the axial direction of the translucent member to an end portion on the other side in the axial direction. Item 1. The ranging sensor according to item 1. The distance measuring sensor according to claim 1 or 2, wherein the light projecting prism portion is formed on an outer peripheral surface of the translucent member. A light receiving mirror for reflecting the reflected light whose traveling direction has been changed by the light receiving prism portion toward the light receiving portion is provided.
The distance measuring sensor according to any one of claims 1 to 3, wherein the light receiving mirror is configured to rotate integrally with the light projecting mirror. The distance measuring sensor according to any one of claims 1 to 4, wherein the light projecting prism portion includes a plane formed along the circumferential direction of the translucent member.

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