JP2020003329A - Optical device, distance measuring device, and distance measuring method - Google Patents

Abstract

To provide an optical device with which it is possible to observe safety standards relating to the intensity of a laser beam and measure the distance of an object existing at a remote position with good accuracy.SOLUTION: The optical device comprises: a plurality of light projection units each including a light source 11 for emitting emission light and an emitted light deflection element 12, and each emitting the emission light deflected by the emitted light deflection element as irradiation light having an instantaneous irradiation field; and a light receiving unit including a reflected light deflection element 21 for direction variably deflecting reflected light of the irradiation light having been reflected by an object and a light receiving element 22 for receiving the reflected light having been deflected by the reflected light deflection element, the solid angle of an instantaneous visual field being larger than the solid angle of the instantaneous irradiation field of the respective irradiation light.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an optical device that emits emitted light and receives the emitted light, a distance measuring device that measures a distance to an object, and a distance measuring method.

  A distance measuring apparatus including an optical device measures a distance to an object by scanning a laser beam in a target area, that is, measures a distance. Examples of such a distance measuring device include an optical scanning unit in which a movable unit swings, a light source unit that emits pulse light toward a light reflecting surface of the movable unit, a light receiving unit that receives reflected light of the pulse light, and an object. Patent Literature 1 discloses an optical distance measuring device including a distance measuring unit that measures a distance to the optical distance measuring device.

JP 2011-053137 A

  Laser light is scattered when irradiated on an object. For this reason, as the object irradiated with the laser beam moves away from the distance measuring device, the amount of laser light received by the distance measuring device decreases. Therefore, in order to measure the distance of an object located far from the distance measuring apparatus, it is desirable to emit the laser light at a high output.

  However, laser light may be harmful to the human body when the power density is high. For this reason, the output of laser light is restricted by safety standards. Therefore, when measuring the distance to an object located at a long distance, one of the problems is that the amount of laser light received by the distance measuring device is small with respect to laser light complying with safety standards.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an optical device that adheres to safety standards regarding the intensity of laser light and that can accurately measure the distance of a distant object. One of the issues.

  The optical device according to claim 1 of the present application includes a plurality of light emitting units each including a light source that emits outgoing light and an outgoing light deflecting element that deflects the outgoing light in a variable direction, and the outgoing light is reflected by an object. A reflected light deflecting element for deflecting the reflected light in a variable direction and a light receiving element for receiving the reflected light deflected by the reflected light deflecting element, and a solid angle of an instantaneous irradiation field of each of the plurality of light projecting units. And a light receiving section having a large solid angle in the instantaneous field of view.

  The distance measuring apparatus according to claim 6 of the present application is configured such that a plurality of light emitting units each including a light source for emitting outgoing light and an outgoing light deflecting element for deflecting the outgoing light in a variable direction, and the outgoing light is reflected by an object. And a light receiving element for receiving the reflected light deflected by the reflected light deflecting element, and a solid angle of an instantaneous irradiation field of each of the plurality of light projecting units. An optical device having a light receiving unit having a larger solid angle in the instantaneous field of view than the optical device, and a distance measuring unit for measuring a distance to the object based on the emitted light and the reflected light.

  The distance measuring method according to claim 7 of the present application is directed to a distance measuring method, wherein a plurality of light emitting units each including a light source for emitting outgoing light and an outgoing light deflecting element for deflecting the outgoing light in a variable direction, and the outgoing light is reflected by an object And a light receiving element for receiving the reflected light deflected by the reflected light deflecting element, and a solid angle of an instantaneous irradiation field of each of the plurality of light projecting units. A light receiving unit having a solid angle greater than the instantaneous field of view, and an optical device, and a distance measuring device having a distance measuring unit that measures the distance to the object based on the emitted light and the reflected light, Simultaneously emitting the emitted light from each of the plurality of light emitting units, causing the light receiving unit to receive the reflected light, and measuring a distance to the object based on the emitted light and the reflected light Performing the step of performing Ranging method to.

  The program according to claim 8, wherein the program includes a plurality of light emitting units each including a light source for emitting the emitted light and an emitted light deflecting element for deflecting the emitted light in a variable direction, and a reflection of the emitted light reflected from an object. Including a reflected light deflecting element that deflects light in a variable direction and a light receiving element that receives the reflected light deflected by the reflected light deflecting element, and a solid angle of the instantaneous irradiation field of each of the plurality of light projecting units. A light receiving unit having a large solid angle of the instantaneous field of view, and a distance measuring unit having a distance measuring unit that measures a distance to the object based on the emitted light and the reflected light; Emission control means for simultaneously emitting the emitted light from each of the light emitting sections, light receiving means for causing the light receiving section to receive the reflected light, and measuring a distance to the object based on the emitted light and the reflected light. Distance measuring means, as machine Characterized in that to.

  The recording medium according to claim 9 of the present application includes a plurality of light emitting units each including a light source that emits outgoing light and an outgoing light deflecting element that deflects the outgoing light in a variable direction, and the outgoing light is reflected by an object. A reflected light deflecting element for deflecting the reflected light in a variable direction and a light receiving element for receiving the reflected light deflected by the reflected light deflecting element, and a solid angle of an instantaneous irradiation field of each of the plurality of light projecting units. An optical device having a light receiving unit having a large solid angle of the instantaneous field of view, and a distance measuring unit having a distance measuring unit that measures a distance to the object based on the emitted light and the reflected light. Emission control means for simultaneously emitting the emitted light from each of the plurality of light emitting sections, light receiving means for causing the light receiving section to receive the reflected light, and measuring a distance to the object based on the emitted light and the reflected light. Function as distance measuring means Wherein the program causing is recorded.

FIG. 2 is a block diagram illustrating a configuration of a distance measuring apparatus according to the first embodiment. FIG. 4 is an explanatory diagram illustrating an operation principle of a light projecting system of the distance measuring apparatus according to the first embodiment. FIG. 3 is an explanatory diagram illustrating an operation principle of a light receiving system of the distance measuring apparatus according to the first embodiment. FIG. 2 is a perspective view illustrating an example of the arrangement of a light projecting unit and a light receiving unit of the distance measuring apparatus according to the first embodiment. FIG. 4 is a conceptual diagram illustrating an instantaneous irradiation field of a light projecting unit and an instantaneous field of view of a light receiving unit according to a distance from the distance measuring apparatus according to the first embodiment. FIG. 3 is a conceptual diagram illustrating a solid angle of an instantaneous irradiation field on a virtual plane at a predetermined distance from the distance measuring apparatus according to the first embodiment. FIG. 3 is a conceptual diagram illustrating a solid angle of an instantaneous visual field on a virtual plane at a predetermined distance from the distance measuring apparatus according to the first embodiment. FIG. 3 is a conceptual diagram illustrating an instantaneous irradiation field and an instantaneous visual field on a virtual plane at a predetermined distance from the distance measuring apparatus according to the first embodiment. 4 is a processing flow illustrating a distance measuring method of the distance measuring apparatus according to the first embodiment. FIG. 4 is a perspective view illustrating another example of the arrangement of the light projecting unit and the light receiving unit of the distance measuring apparatus according to the first embodiment. FIG. 4 is an explanatory diagram illustrating another configuration example of the light projecting unit of the distance measuring apparatus according to the first embodiment. FIG. 9 is a block diagram illustrating a configuration of a distance measuring apparatus according to a second embodiment. FIG. 13 is a perspective view illustrating an example of the arrangement of a light projecting unit and a light receiving unit of the distance measuring apparatus according to the third embodiment. FIG. 9 is a conceptual diagram illustrating an instantaneous irradiation field and an instantaneous field of view on a virtual plane at a predetermined distance from a distance measuring apparatus according to a third embodiment. FIG. 14 is a perspective view illustrating another example of the arrangement of the light projecting unit and the light receiving unit of the distance measuring apparatus according to the third embodiment. FIG. 14 is a perspective view illustrating another example of the arrangement of the light projecting unit and the light receiving unit of the distance measuring apparatus according to the third embodiment.

  Hereinafter, an embodiment in which the optical device of the present invention is used for a distance measuring device will be described.

  FIG. 1 shows functional blocks of a distance measuring apparatus 100 according to the present embodiment. In FIG. 1, light projecting units 10a and 10b are light emitting devices that emit outgoing light. The light emitting units 10a and 10b have the same configuration as each other. The light sources 11 of the light projecting units 10a and 10b are, for example, laser elements capable of emitting pulsed light as emitted light.

  The light deflection element 12 is a device that deflects a light beam according to a control signal. In other words, the light deflecting element 12 can deflect the pulse light in a variable direction. The light deflection element 12 has an outgoing light reflecting member including a light reflecting surface (not shown). As the light deflection element 12, a MEMS (Micro Electro Mechanical Systems) mirror device, a polygon mirror, or the like can be used. The light deflecting element 12 may be a light deflecting element having no light reflecting surface. An example of such a light deflecting element 12 is an acousto-optic deflector (AO deflector).

  The light deflecting element 12 reflects the pulse light emitted from the light source 11 on the light reflecting surface, and can emit irradiation light toward a predetermined region to be scanned (hereinafter, referred to as a scanning region). is there. Therefore, the light deflection element 12 functions as an output light polarization element.

  In this manner, the light projecting units 10a and 10b emit the emitted light, each of which is polarized by the light deflecting element 12, toward the scanning target area as irradiation light having an instantaneous irradiation field. The irradiation light is reflected by an object existing in the scanning target area. The irradiation light reflected by the object travels toward the distance measuring apparatus 100 as reflected light.

  The light receiving unit 20 is a light receiving device that receives the reflected light and generates a light receiving signal that is an electric signal. The light deflection element 21 is a device that can deflect a light beam according to a control signal. In other words, the light deflecting element 21 can deflect the reflected light of the irradiation light reflected by the object in a variable direction. The light deflecting element 21 has a reflected light reflecting member including a light reflecting surface (not shown). As the light deflection element 21, a MEMS mirror device or the like can be used similarly to the light deflection element 12. Therefore, the light deflecting element 21 functions as a reflected light deflecting element.

  The light receiving element 22 receives the reflected light deflected by the light deflecting element 21 and generates a light receiving signal that is an electric signal. As the light receiving element 22, for example, an avalanche photodiode (Avalanche Photodiode) or the like can be used.

  The control unit 30 controls the pulse light emitted from each of the light sources 11 of the light projecting units 10a and 10b, and controls the light reflection of the light deflecting element 21 of the light receiving unit 20 and the light deflecting element 12 of each of the light projecting units 10a and 10b. Controls the angle of the surface. The control unit 30 is a computer having at least a central processing unit, a main storage device, and an auxiliary storage device.

  The light source control unit 31 controls the light emission of each of the light sources 11 of the light emitting units 10a and 10b. Specifically, the light emission is controlled with reference to a table (not shown) in which the light emission timing is specified so that the light source 11 emits the pulse light.

  The mirror control unit 32 controls the inclination angle of the light reflecting surface of the light deflecting element 12 of each of the light projecting units 10a and 10b. Specifically, the mirror control unit 32 reflects the pulse light on the light reflecting surface of the light deflecting element 12 and scans the scanning target area with the reflected irradiation light. To control the angle of tilt.

  The mirror controller 32 controls the angle of inclination of the light reflecting surface of the light deflecting element 21 of the light deflecting element 21 of the light receiving unit 20. Specifically, the mirror control unit 32 determines the direction (angle of inclination) of the light reflecting surface of the light deflecting element 21 of the light receiving unit 20 and the direction of the light reflecting surface of the light deflecting element 12 of the light projecting units 10a and 10b ( The inclination of the light reflecting surface of the light deflecting element 21 is controlled so that the inclination angle is linked. That is, the direction of the light reflecting surface of the light deflecting element 21 of the light receiving unit 20 and the direction of the light reflecting surface of the light deflecting element 12 of the light projecting units 10a and 10b are linked, so that the reflected light is directed toward the light receiving element 22. proceed.

  In other words, the light source control unit 31 and the mirror control unit 32 function as emission control units that simultaneously emit pulse light from each of the light projection units 10a and 10b. The mirror control unit 32 functions as a light receiving unit that causes the light receiving unit 20 to receive the reflected light.

  The distance measurement unit 33 as a distance measurement unit calculates the distance from the distance measurement device 100 to an object in the scanning target area. In other words, the distance measuring unit 33 functions as a distance measuring unit that measures the distance to the object based on the pulse light and the reflected light.

  The distance measuring unit 33 calculates a distance from the distance measuring device 100 to an object in the scanning target area based on the light receiving signal generated by the light receiving element 22. For example, the distance measuring unit 33 calculates the distance using a time-of-flight method. The calculation of the distance to the object is not limited to the time-of-flight method, but may be a phase difference method.

  Specifically, the distance measuring unit 33 determines the emission time of one pulse light emitted by the light source 11 and the irradiation light deflected by the one pulse light is reflected by an object in the scanning target area and reflected light As a result, the light receiving time detected by the light receiving element 22 is obtained. Then, the distance between the distance measuring device 100 and the object is calculated based on the time difference between the emission time and the light reception time.

  Note that a virtual irradiation surface (not shown) is provided in the traveling direction of the irradiation light deflected by the light deflecting element 12. Note that the irradiation surface is not real.

  FIG. 2 is a conceptual diagram showing the operation of the light projecting system including the light projecting units 10a and 10b. In FIG. 2, the pulse light EL <b> 1 emitted from the light source 11 enters the light reflecting surface MR of the light deflecting element 12.

  The light deflecting element 12 reflects the pulse light EL1 incident on the light reflection surface MR. That is, the light deflecting element 12 deflects the pulse light EL1 toward the scanning target region R as the irradiation light EL2.

  The light reflecting surface MR of the light deflecting element 12 is swingably fixed to the main body. Therefore, the light deflecting element 12 deflects the traveling direction of the irradiation light EL2 to a desired direction in the scanning target region R by swinging the light reflecting surface MR.

  The irradiation light EL2 is deflected by the light deflection element 12 so that a desired trajectory is drawn on the irradiation surface VS. The trajectory drawn on the irradiation surface VS is preferably a raster scanning trajectory, a Lissajous scanning trajectory, or the like, but is not limited thereto.

  FIG. 3 is a conceptual diagram illustrating the operation of the light receiving system of the light receiving unit 20. In FIG. 3, the irradiation light EL2 is reflected by the object OB existing in the scanning target region R. The irradiation light EL2 reflected by the object OB travels toward the light receiving unit 20 as reflected light RL. When the reflected light RL is reflected by the light reflecting surface MR of the light deflecting element 21 of the light receiving section 20, it enters the light receiving element 22.

  The light receiving element 22 generates a light receiving signal based on the incident reflected light RL and supplies the generated light receiving signal to the control unit 30. The distance measuring unit 33 of the control unit 30 measures the distance to the object OB based on the time when the pulse light EL1 is emitted and the time when the reflected light RL is received.

  FIG. 4 shows an example of the arrangement of the light projecting units 10a and 10b and the light receiving unit 20 of the distance measuring apparatus 100 according to the present embodiment. As shown in FIG. 4, the light projecting units 10 a and 10 b are arranged in a row on the substrate 40 so as to sandwich the light receiving unit 20.

  Further, the light projecting units 10a and 10b are arranged at equal distances to the light receiving unit 20. Specifically, the distance LH1 from the light receiving unit 20 to the light emitting unit 10a is equal to the distance LH2 from the light receiving unit 20 to the light emitting unit 10b.

  FIG. 5 shows a mode of an instantaneous field of illumination (iFOI) of the light projecting units 10 and 10b and an instantaneous field of view (iFOV) of the light receiving unit 20. In addition, the broken line arrow in the figure has shown the traveling direction of irradiation light EL2.

  Specifically, FIG. 5 shows the instantaneous irradiation fields (iFOI) of the light projecting units 10a and 10b and the instantaneous field of view (iFOV) of the light receiving unit 20 with respect to the traveling direction of the irradiation light EL2 indicated by the broken arrow in the drawing. The cross section in the vertical direction is shown according to the distance from the distance measuring apparatus 100.

  Here, the instantaneous irradiation field (iFOI) is a region irradiated with the emission light EL at the moment of interest. For example, the instantaneous irradiation field (iFOI) is an angle range in which a light source shape (not shown) is projected by a light emitting lens (not shown) of the light emitting units 10a and 10b, or an angle range of each sum. The instantaneous visual field (iFOV) is an angle range in which the light receiving surface of the light receiving unit 20 can be seen by the light receiving lens of the light receiving unit 20.

  The two-dot chain line in the figure indicates the instantaneous irradiation field (iFOI (a)) of the light emitting unit 10a and the instantaneous irradiation field (iFOI (b)) of the light emitting unit 10b. The dashed line in the figure indicates the instantaneous visual field (iFOV) of the light receiving unit 20.

  Each of the light emitting units 10a and 10b emits the irradiation light EL2 with an output satisfying the safety standard. The safety standard is determined based on the light intensity at a predetermined distance from the distance measuring device 100. The safety standard is determined based on, for example, the light intensity at a distance of 100 mm from the distance measuring device 100. Further, the instantaneous irradiation fields (iFOI (a), iFOI (b)) of the emitted light EL emitted from the light projecting units 10a and 10b are smaller than the instantaneous field of view (iFOV).

  The positional relationship of each of the instantaneous irradiation fields (iFOI (a), iFOI (b)) in the instantaneous visual field (iFOV) changes according to the distance from the distance measuring apparatus 100. Specifically, as the distance from the distance measuring apparatus 100 increases, the instantaneous irradiation fields (iFOI (a), iFOI (b)) approach each other and come into contact with each other at a predetermined distance from the distance measuring apparatus 100.

  The distances L1 to L4 are distances from the distance measuring device 100. For example, the distances L1 to L4 are distances from the light receiving unit 20. Further, the distances L1 to L4 may be distances from the light emitting unit 10a or the light emitting unit 10b.

  The distance L1 is a distance from the distance measuring device 100 defined by the safety standard. At the position of the distance L1, the instantaneous irradiation field (iFOI (a)) of the light emitting unit 10a and the instantaneous irradiation field (iFOI (b)) of the light emitting unit 10b are arranged outside the instantaneous field of view (iFOV) of the light receiving unit 20. Have been.

  Therefore, the intensity of the irradiation light EL2 emitted from the light emitting units 10a and 10b at the position of the distance L1 satisfies the safety standard. At the position of the distance L1, one or both of the instantaneous irradiation field (iFOI (a)) of the light emitting unit 10a and the instantaneous irradiation field (iFOI (b)) of the light emitting unit 10b are set to the light receiving unit. It may be arranged inside the instantaneous visual field (iFOV) of 20. In this case, the output of the irradiation light EL2 may be appropriately adjusted so as to satisfy the safety standard at the position of the distance L1.

  The distance L2 is a distance from the distance measuring device 100, and is longer than the distance L1. The distance L2 is, for example, 50 m from the distance measuring device 100. At the position of the distance L2, a part of the instantaneous irradiation field (iFOI (a)) of the light emitting unit 10a and a part of the instantaneous irradiation field (iFOI (b) of the light emitting unit 10b are inside the instantaneous field of view (iFOV) of the light receiving unit 20. Therefore, when the object OB exists at the position of the distance L2, the light receiving unit 20 can obtain a sufficient reflected light RL for measuring the distance of the object OB. 100 can measure the distance of the object OB existing at a distance longer than the distance L2.

  The distance L3 is a distance from the distance measuring device 100, and is longer than the distance L2. The distance L3 is, for example, 100 m from the distance measuring device 100. At the position of the distance L3, a part of the instantaneous irradiation field (iFOI (a)) of the light emitting unit 10a and a part of the instantaneous irradiation field (iFOI (b) of the light emitting unit 10b are located inside the instantaneous field of view (iFOV) of the light receiving unit 20. It is arranged in.

  In addition, the instantaneous irradiation field (iFOI (a)) of the light projecting unit 10a and the instantaneous irradiation field (iFOI (b)) of the light projecting unit 10b arranged inside the instantaneous field of view (iFOV) of the light receiving unit 20 at the distance L3. The ratio of the area is larger than the distance L2.

  Therefore, when the object OB exists at the position of the distance L3, the light receiving unit 20 can obtain sufficient reflected light RL for measuring the distance of the object OB. For this reason, the ranging device 100 can perform ranging in a state where the density of the instantaneous irradiation field (iFOI) arranged in the instantaneous field of view (iFOV) is higher than when the object OB exists at the distance L2. .

  The distance L4 is a distance from the distance measuring device 100, and is longer than the distance L3. The distance L4 is, for example, 200 m from the distance measuring device 100.

  At the position of the distance L4, the instantaneous irradiation field (iFOI (a)) of the light emitting unit 10a and the instantaneous irradiation field (iFOI (b)) of the light emitting unit 10b are arranged inside the instantaneous field of view (iFOV) of the light receiving unit 20. ing.

  That is, the instantaneous irradiation field (iFOI (a)) of the light projecting unit 10a and the instantaneous irradiation field (iFOI (b)) of the light projecting unit 10b arranged inside the instantaneous field of view (iFOV) of the light receiving unit 20 at the distance L4. The ratio of the area is larger than the distance L3.

  Therefore, when the object OB exists at the position of the distance L4, the light receiving unit 20 can obtain a sufficient reflected light RL for measuring the distance of the object OB. For this reason, the ranging device 100 can perform ranging in a state where the density of the instantaneous irradiation field (iFOI) arranged in the instantaneous field of view (iFOV) is higher than when the object OB exists at the distance L3. .

  FIG. 6A shows instantaneous irradiation fields (iFOI (a), iFOI (b)) on the irradiation surface VS at the distance L4 in FIG. In FIG. 6A, the irradiation surface VS is arranged at a position at a predetermined distance (r) from the light source 11. The instantaneous irradiation fields (iFOI (a), iFOI (b)) of the light source 11 of the light projecting units 10a, 10b are shown on the irradiation surface VS.

  The instantaneous irradiation fields (iFOI (a), iFOI (b)) on the irradiation surface VS are shown in a rectangular shape. Note that the instantaneous irradiation field (iFOI (a), iFOI (b)) on the irradiation surface VS is not limited to a rectangular shape, and the light source 11 may be configured to have, for example, a circular shape or an elliptical shape.

  Here, the solid angle refers to a portion divided by a conical surface formed by moving a half line coming out of the same point in space. The solid angle can be represented by the size of an area obtained by cutting the conical surface from a sphere having a radius of 1 around the point.

  In the present embodiment, when the same point in space is the light source 11, the solid angle at which the light source 11 sees the instantaneous irradiation field (iFOI (a), iFOI (b)) is determined by the instantaneous irradiation field (iFOI) on the irradiation surface VS. (A), iFOI (b)). A line connecting the center CI of the instantaneous irradiation field (iFOI (a), iFOI (b)) and the light source 11 is defined as an axis AX1.

  FIG. 6B shows the instantaneous visual field (iFOV) on the irradiation surface VS at the distance L4 in FIG. In FIG. 6B, the irradiation surface VS is arranged at a position at a predetermined distance (r) from the light receiving element 22. That is, the distance from the light source 11 to the irradiation surface VS in FIG. 6A is equal to the distance from the light receiving element 22 to the irradiation surface VS.

  The instantaneous visual field (iFOV) of the light receiving unit 20 is shown on the irradiation surface VS. The instantaneous visual field (iFOV) on the irradiation surface VS is shown in a rectangular shape. Note that the instantaneous field of view (iFOV) on the irradiation surface VS is not limited to a rectangular shape, and the light receiving element 22 of the light receiving unit 20 may be configured to have, for example, a circular shape or an elliptical shape.

  Further, inside the instantaneous visual field (iFOV) on the irradiation surface VS, the instantaneous irradiation fields (iFOI (a), iFOI (b)) shown in FIG. 6A are shown. The instantaneous visual field (iFOV) on the irradiation surface VS is larger than the instantaneous irradiation field (iFOI (a), iFOI (b)).

  In this embodiment, when the same point in space is the light receiving element 22, the solid angle at which the light receiving element 22 looks at the instantaneous field of view (iFOV) is represented by the instantaneous field of view (iFOV) on the irradiation surface VS.

  Therefore, the solid angle at which the light source 11 sees the instantaneous irradiation field (iFOI (a), iFOI (b)) is smaller than the solid angle at which the light receiving element 22 looks at the instantaneous field of view (iFOV). In other words, the solid angle at which the light receiving element 22 looks at the instantaneous visual field (iFOV) is larger than the solid angle at which the light source 11 looks at the instantaneous irradiation field (iFOI (a), iFOI (b)). Note that a line connecting the center CV of the instantaneous visual field (iFOV) and the light receiving element 22 is defined as an axis AX2.

  FIG. 6C shows an instantaneous irradiation field (iFOI (a), iFOI (b)) and an instantaneous field of view (iFOV) on the irradiation surface VS located at the distance L4. The instantaneous irradiation fields (iFOI (a), iFOI (b)) and the instantaneous field of view (iFOV) on the irradiation surface VS are shown in a rectangular shape.

  As shown in FIG. 6C, on the irradiation surface VS located at the distance L4, the irradiation region RI is formed by the instantaneous irradiation fields (iFOI (a), iFOI (b)) of the light emitting units 10a and 10b. . The irradiation area RI is an area illuminated by each of the light emitting units 10a and 10b.

  The irradiation area RI is, for example, an area having at least half of the brightness of the irradiation light EL2 at the center of the irradiation light EL2 on the irradiation surface VS located at the distance L4.

  The visual field region RV is formed by the instantaneous visual field (iFOV) of the light receiving unit 20 on the irradiation surface VS located at the distance L4. The irradiation region RI includes the entire viewing region RV on the irradiation surface VS located at the distance L4.

  Note that the position on the scanning region R in which the irradiation region RI includes the entire instantaneous visual field RV, that is, the distance from the distance measuring device 100 can be adjusted as appropriate. For example, the distance from the distance measuring device 100 may be a distance closer to the distance measuring device 100 than the distance L4, such as the distance L2 or the distance L3, or a distance farther than the distance L4 to the distance measuring device 100. It may be.

  FIG. 7 is a processing flow illustrating a distance measuring method of the distance measuring apparatus 100. As shown in FIG. 7, the control unit 30 simultaneously emits the irradiation light EL2 from each of the light projecting units 10a and 10b (step S01). In other words, the distance measuring apparatus 100 simultaneously emits the irradiation light EL2 from each of the light emitting units 10a and 10b. Specifically, the control unit 30 causes the light sources 11 of the light emitting units 10a and 10b to emit pulsed light EL1. The control unit 30 deflects the pulse light EL1 by the light deflecting elements 12 of the light projecting units 10a and 10b. As a result, the irradiation light EL2 is simultaneously emitted from each of the light emitting units 10a and 10b.

  Next, the control unit 30 causes the light receiving unit 20 to receive the reflected light RL of the irradiation light EL2 reflected by the object OB (Step S02). In other words, in the distance measuring apparatus 100, the light receiving unit 20 receives the reflected light RL with the instantaneous visual field (iFOV). Specifically, the control unit 30 deflects the reflected light RL by the light deflection element 21 of the light receiving unit 20 and causes the light receiving element 22 to receive the deflected reflected light RL.

  The control unit 30 measures the distance to the object OB based on the pulse light EL1 and the reflected light RL (Step S03). In other words, the distance measuring device 100 measures the distance to the object OB based on the pulse light EL1 and the reflected light RL.

  Specifically, the control unit 30 acquires the emission time of one pulse light emitted by the light source 11 and the light reception time at which the one pulse light is detected by the light receiving element 22 as the reflected light RL. The control unit 30 calculates the distance between the distance measuring device 100 and the object OB based on the time difference between the emission time and the light reception time.

  As described above, the intensity of each emitted light EL emitted from the light receiving unit 20 and the light emitting units 10a and 10b satisfies the safety standard at the position of the distance L1.

  In addition, after the distance L2, which is farther than the distance L1, from the distance measuring apparatus 100, the instantaneous irradiation fields (iFOI (a), iFOI (b)) of the light projecting units 10a, 10b are within the instantaneous field of view (iFOV). Are arranged. Further, as the distance from the distance measuring apparatus 100 increases, the ratio of the area of the instantaneous irradiation field (iFOI (a), iFOI (b)) arranged in the instantaneous field of view (iFOV) increases. Therefore, according to the distance measuring apparatus 100 according to the present embodiment, it is possible to observe the safety standard regarding the output of the laser beam and accurately measure the distance of the object OB located at a long distance.

  The information processing performed by the distance measuring apparatus 100 of the present invention can be executed by a program that executes the information processing performed by the distance measuring apparatus 100 in the above embodiment. The program for executing the information processing method of the present invention is recorded on a computer-readable recording medium, and can be suitably used. For example, the distance measuring apparatus 100 of the present invention can read the program of the present invention from a recording medium and execute the program of the present invention.

  Further, the arrangement of the light projecting units 10a and 10b is not limited to the arrangement example of the present embodiment. For example, as shown in FIG. The portions 10a and 10b may be arranged on the substrate 40 in a row in a direction perpendicular to the arrangement direction.

  When the light projecting units 10a and 10b are arranged as described above, it is preferable that the light projecting units 10a and 10b have the same distance to the light receiving unit 20, as described in FIG. Specifically, the distance LV1 from the light receiving unit 20 to the light emitting unit 10a may be equal to the distance LV2 from the light receiving unit 20 to the light emitting unit 10b.

  Further, the adjustment of the instantaneous irradiation field (iFOI (a), iFOI (b)) may be performed by blocking the irradiation light EL2 emitted from the light source 11. FIG. 9 shows a configuration example in which the light-projecting units 10a and 10b are provided with a shielding member SC. As shown in FIG. 9, the shielding member SC is provided between the light source 11 and the light deflecting element 12. The shielding member SC shields a part of the pulsed light EL1. Therefore, a part of the pulse light EL1 is shielded by the shield member SC and enters the light reflection surface MR of the light deflection element 12.

  By adjusting the instantaneous irradiation field (iFOI (a), iFOI (b)) by the shielding member SC, it is easy to set the output of the light source 11 that emits the irradiation light EL2. For example, when cutting half of the pulse light EL1 emitted from the light source 11, this can be realized by shielding half of the pulse light EL1 with the shielding member SC. Therefore, it is easy to set the power of the light source 11 that emits pulsed light with a simple configuration without requiring a configuration for controlling the current supplied to the light source 11.

  In the first embodiment, the light receiving unit 20 is configured to have a function as a light receiving unit. However, the light receiving unit may be configured to have not only a function as a light receiving unit but also a function as a light emitting unit. Note that the same components as those of the distance measuring apparatus 100 according to the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 10 illustrates functional blocks of the distance measuring apparatus 100 according to the second embodiment. As shown in FIG. 10, the light source 51 of the light emitting / receiving unit 50 is a light emitting device that emits outgoing light. The light source 51 has the same configuration as the light source 11 of the light emitting units 10a and 10b.

  The light deflection element 52 is a device that deflects a light beam according to a control signal. In other words, the light deflection element 52 can variably deflect the direction of the pulse light EL1 and the direction of the reflected light RL. The light deflecting element 52 has an outgoing light reflecting member including a light reflecting surface (not shown).

  As the light deflection element 52, a MEMS mirror device or the like can be used similarly to the light deflection element 12. The light deflecting element 52 can reflect the pulse light on the light reflecting surface and emit the irradiation light EL2 toward the scanning target region R, and can deflect the reflected light toward the light receiving element 53. Therefore, the light deflecting element 52 functions as an outgoing light polarizing element and a reflected light polarizing element.

  Note that a beam splitter (not shown) may be provided between the light source 51 and the light deflecting element 52 to separate the pulse light EL1 from the reflected light RL.

  The light receiving element 53 receives the reflected light RL deflected by the light deflecting element 52 and generates a light receiving signal that is an electric signal. As the light receiving element 53, for example, an avalanche photodiode or the like can be used.

  Thus, the light emitting / receiving unit 50 has a function of a light emitting unit and a function of a light receiving unit. Therefore, the axis AX1 of the instantaneous irradiation field (iFOI) of the light emitting and receiving unit 50 coincides with the axis AX2 of the instantaneous visual field (iFOV).

  As described above, according to the distance measuring apparatus 100 of the present embodiment, similarly to the distance measuring apparatus 100 of the first embodiment, the safety standard regarding the output of the laser beam is observed, and the distance of the object OB located at a long distance is measured. Can be performed with high accuracy. Also, since the axis AX1 of the instantaneous irradiation field (iFOI) of the light emitting and receiving unit 50 coincides with the axis AX2 of the instantaneous visual field (iFOV), for example, the distance from the distance measuring device 100 is shorter than the distance L2. Even if the object OB exists in the object OB, it is possible to accurately measure the distance of the object OB.

  In the distance measuring apparatus 100 according to the first embodiment, the light projecting unit 10a and the light projecting unit 10b are arranged at different positions in the instantaneous visual field (iFOV). However, the light projecting unit 10a and the light projecting unit 10b may be arranged at positions overlapping each other in the instantaneous visual field (iFOV). Note that the same components as those of the distance measuring apparatus 100 according to the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 11 illustrates an example of the arrangement of the light projecting unit 10 and the light receiving unit 20 of the distance measuring apparatus 100 according to the third embodiment. As shown in FIG. 11, the light projecting units 10a to 10d are arranged in a row on the substrate 40 so as to sandwich the light receiving unit 20. Specifically, in the light emitting units 10a to 10d, the light emitting unit 10a and the light emitting unit 10d are arranged at the end of the row, and the light emitting units 10b and 10c are arranged between them. A light receiving unit 20 is arranged between the light emitting units 10b and 10c.

  Further, the distance between the light emitting unit 10a and the light emitting unit 10b, the distance between the light emitting unit 10b and the light receiving unit 20, the distance between the light receiving unit 20 and the light emitting unit 10c, and the distance between the light emitting unit 10c And the light projecting unit 10d are equally spaced.

  FIG. 12 shows an instantaneous irradiation field (iFOI (a) to iFOI (d)) and an instantaneous visual field (iFOV) on the irradiation surface VS located at the distance L4. Note that the instantaneous irradiation fields (iFOI (a) to iFOI (d)) and the instantaneous field of view (iFOV) on the irradiation surface VS are shown in a rectangular shape.

  As shown in FIG. 12, on the irradiation surface VS located at the distance L4, the irradiation region RI is formed by the instantaneous irradiation fields (iFOI (a) to iFOI (d)) of the light emitting units 10a to 10d. .

  Specifically, the irradiation area RI is an area illuminated by each of the light emitting units 10a to 10d on the irradiation surface VS. The irradiation region RI includes the entire viewing region RV.

  The instantaneous irradiation field (iFOI (a), iFOI (b)) on the irradiation surface VS of each of the set of light emitting units 10a and 10b among the light emitting units 10a to 10d is an instantaneous field of view (iFOV) on the irradiation surface VS. Above each other on top. In addition, the instantaneous irradiation field (iFOI (c), iFOI (d)) on the irradiation surface VS of each of the pair of light emitting units 10c and 10d among the light emitting units 10a to 10d has an instantaneous field of view ( on iFOV) at a distance L4.

  The visual field region RV is formed by the instantaneous visual field (iFOV) of the light receiving unit 20 on the irradiation surface VS located at the distance L4. The irradiation region RI includes the entire viewing region RV on the irradiation surface VS located at the distance L4.

  Here, the sum of the intensities of the outgoing light ELs emitted into the instantaneous visual field (iFOV) at a distance from the distance measuring device 100 among the outgoing light ELs emitted from the light projecting units 10a to 10d is determined by distance measurement. The irradiation light intensity at a distance from the device 100 is assumed.

  As described above, the instantaneous irradiation fields (iFOI (a), iFOI (b)) on the irradiation surface VS of each of the light emitting units 10a and 10b overlap each other on the instantaneous field of view (iFOV) on the irradiation surface VS. In addition, it is possible to increase the irradiation light intensity in a region where the instantaneous irradiation fields (iFOI (a), iFOI (b)) overlap each other. Similarly, the instantaneous irradiation fields (iFOI (c), iFOI (d)) on the irradiation surface VS of each of the light projecting units 10c, 10d overlap each other on the instantaneous field of view (iFOV) on the irradiation surface VS. It is possible to increase the irradiation light intensity in a region where the instantaneous irradiation fields (iFOI (c), iFOI (d)) overlap each other. Therefore, the amount of the reflected light RL received by the light receiving unit 20 can be increased.

  As described above, according to the distance measuring apparatus 100 of the present embodiment, similarly to the distance measuring apparatus 100 of the first embodiment, the safety standard regarding the output of the laser beam is observed, and the distance of the object OB located at a long distance is measured. Can be performed with high accuracy. In particular, since the amount of the reflected light RL received by the light receiving unit 20 can be increased, the distance measurement of the object OB can be accurately performed.

  Note that the arrangement of the light emitting units 10a and 10b is not limited to the arrangement example of the present embodiment. For example, as shown in FIG. The sections 10a to 10d may be arranged in a row in a direction perpendicular to the arrangement direction.

  When the light projecting units 10a to 10d are arranged in this manner, as described in FIG. 11, the distance between the light projecting unit 10a and the light projecting unit 10b and the distance between the light projecting unit 10b and the light receiving unit 20 The distance between the light receiving unit 20 and the light projecting unit 10c and the distance between the light projecting unit 10c and the light projecting unit 10d may be equally arranged.

  Further, each of the light emitting units 10a to 10d may be arranged on the substrate 40 at a position equidistant from the light receiving unit 20. FIG. 14 shows an example of the arrangement of the light projecting unit of the distance measuring apparatus 100 according to the modification. As shown in FIG. 14, the distance LH1 from the light receiving unit 20 to the light emitting unit 10a is equal to the distance LH2 from the light receiving unit 20 to the light emitting unit 10c. The distance LV1 from the light receiving unit 20 to the light emitting unit 10b is equal to the distance LV2 from the light receiving unit 20 to the light emitting unit 10d. Further, the distances LV1, LV2, LH1, LH2 are equal to each other.

  The light receiving unit 20 of the present embodiment may be implemented by the light emitting and receiving unit 50 described in the second embodiment.

REFERENCE SIGNS LIST 100 Distance measuring devices 10 a to 10 d Light projecting unit 11 Light source 12 Light deflecting element 20 Light emitting / receiving unit 21 Light source 22 Light receiving element 23 Light deflecting element 30 Control unit 40 Distance measuring unit iFOI Instantaneous irradiation field iFOV Instantaneous field of view OB Object VS Irradiation surface

Claims (9)

A light source that emits outgoing light and an outgoing light deflecting element that deflects the outgoing light in a variable direction are included, and the outgoing light that is each polarized by the outgoing light deflector is irradiated light having an instantaneous irradiation field. A plurality of light emitting units for emitting light,
The illuminating light includes a reflected light deflecting element for deflecting the reflected light reflected by the object in a variable direction and a light receiving element for receiving the reflected light deflected by the reflected light deflecting element, and the moment of each of the illuminating light is included. A light receiving unit having a larger solid angle of the instantaneous field of view than the solid angle of the irradiation field,
An optical device, comprising:   On an irradiation surface at a predetermined distance from the light receiving unit, an irradiation area formed by the instantaneous irradiation fields of the plurality of light emitting units includes a visual field area formed by the instantaneous visual field. The distance measuring device according to claim 1.   The instantaneous irradiation field of each of at least one set of the light emitting units of the plurality of light emitting units overlaps with each other at a predetermined distance from the light receiving unit on the instantaneous field of view. Optical device.   The optical device according to claim 1, wherein the light projecting unit includes a shielding member that shields a part of the emitted light between the light source and the emitted light deflecting element.   5. The optical device according to claim 1, wherein an axis of an instantaneous irradiation field of one of the plurality of light emitting units coincides with an axis of the instantaneous field of view. 6. A plurality of light projecting units each including a light source for emitting outgoing light and an outgoing light deflecting element for deflecting the outgoing light in a variable direction; and a reflected light deflection for deflecting the reflected light of the outgoing light reflected by an object in a variable direction. A light receiving unit that includes a light receiving element that receives the reflected light deflected by the element and the reflected light deflecting element, and that has a larger solid angle of the instantaneous field of view than the solid angle of the instantaneous irradiation field of each of the plurality of light projecting units; An optical device having
A distance measuring unit that measures a distance to the object based on the emitted light and the reflected light,
A distance measuring device comprising: A light source that emits outgoing light and an outgoing light deflecting element that deflects the outgoing light in a variable direction are included, and the outgoing light that is each polarized by the outgoing light deflector is irradiated light having an instantaneous irradiation field. A plurality of light emitting units that emit, and a light receiving element that receives the reflected light deflected by the reflected light deflecting element and the reflected light deflecting element that deflects the reflected light reflected by the object in the direction, and And a light receiving unit having a larger solid angle of the instantaneous field of view than the solid angle of the instantaneous irradiation field of the irradiation light,
A distance measuring unit that measures a distance to the object based on the emitted light and the reflected light, and a distance measuring method executed by a distance measuring device,
Simultaneously emitting the irradiation light from each of the plurality of light emitting units,
Receiving the reflected light with the instantaneous field of view at the light receiving unit;
A step of measuring the distance to the object based on the emitted light and the reflected light,
A distance measuring method comprising: A light source that emits outgoing light and an outgoing light deflecting element that deflects the outgoing light in a variable direction are included, and the outgoing light that is each polarized by the outgoing light deflector is irradiated light having an instantaneous irradiation field. A plurality of light emitting units for emitting light,
The illuminating light includes a reflected light deflecting element for deflecting the reflected light reflected by the object in a variable direction and a light receiving element for receiving the reflected light deflected by the reflected light deflecting element, and the moment of each of the illuminating light is included. A light receiving unit having a larger solid angle of the instantaneous field of view than the solid angle of the irradiation field,
A distance measuring unit that measures a distance to the object based on the emitted light and the reflected light,
Simultaneously emitting the irradiation light from each of the plurality of light emitting units,
Receiving the reflected light with the instantaneous field of view at the light receiving unit;
A step of measuring the distance to the object based on the emitted light and the reflected light,
A program characterized by the following. A light source that emits outgoing light and an outgoing light deflecting element that deflects the outgoing light in a variable direction are included, and the outgoing light that is each polarized by the outgoing light deflector is irradiated light having an instantaneous irradiation field. A plurality of light emitting units for emitting light,
The illuminating light includes a reflected light deflecting element for deflecting the reflected light reflected by the object in a variable direction and a light receiving element for receiving the reflected light deflected by the reflected light deflecting element, and the moment of each of the illuminating light is included. A light receiving unit having a larger solid angle of the instantaneous field of view than the solid angle of the irradiation field,
A distance measuring unit that measures a distance to the object based on the emitted light and the reflected light,
Simultaneously emitting the irradiation light from each of the plurality of light emitting units,
Receiving the reflected light with the instantaneous field of view at the light receiving unit;
A step of measuring the distance to the object based on the emitted light and the reflected light,
A recording medium characterized by recording a program for causing a computer to execute the program.

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