JP2022187581A - Distance measuring device - Google Patents

Abstract

To provide a distance measuring device that can suppress generation of variations in the accuracy of a distance measurement according to the direction of measurement and can reduce the size of a device.SOLUTION: A distance measuring device 2 includes: a light projection unit 3 with a light projection element 3a; a light reception unit 4 with a light receiving element 4a and a light receiving lens 7; and a scan unit 6 for scanning measurement light emitted from the light projection unit 3 to a measurement target space and guiding the reflected light of the measurement light from an object to the light receiving unit 4. The light projection unit 3 is supported by the light receiving lens 7, with the optical axis of the light projection element 3a being along the optical axis of the light receiving lens 7.SELECTED DRAWING: Figure 4

Description

The present invention comprises a light projecting section including a light projecting element, a light receiving section including a light receiving element and a light receiving lens, and a measurement light emitted from the light projecting section scanning a space to be measured, and scanning an object with respect to the measurement light. a scanning unit that guides reflected light from the light receiving unit to the light receiving unit.

Patent Document 1 discloses an example of the rangefinder described above.
As shown in FIG. 11, the distance measuring device 100 includes a light projecting section 103, a light receiving section 104, a deflection mirror 105, a scanning section 106, a light receiving lens 107, a control board 108, and the like.

A scanning unit 106 is provided with a motor 160 installed on the inner wall of the upper surface of the upper casing 100C and an encoder 161 for detecting the rotation state of the motor 160. 105 is attached.

A light projecting portion 103 and a light receiving portion 104 are arranged coaxially with the rotating shaft of the motor 160 . The light projecting unit 103 includes a light emitting element 103a, which is a laser diode emitting light having a wavelength in the near-infrared region, and a light projecting lens 103b. The light receiving section 104 includes a light receiving element 104a made of a photodiode and an amplifier circuit 104, and is mounted on a control substrate 108 arranged at the bottom of the lower casing 100A.

The control board 108 is provided with a signal processing section that drives and controls the motor 160 based on the signal from the encoder 161, controls the light emission of the light emitting element 103a at a predetermined time, and processes the signal received by the light receiving element 104a. It is

A peripheral portion of the light receiving lens 107 is fixed to a collar portion 172 of a lens holder 170 having four legs 171 . A cylindrical projection lens holder 103B is inserted into a cylindrical notch 107a formed at the center of the optical axis of the light receiving lens 107. As shown in FIG. The projection lens 103b is held by the projection lens holder 103B. The projection lens 103b is fixed from above by a lens retainer 103C.

An end portion of the substrate 103d on which the light emitting element 103a is mounted is fixed to the lens holder 170 with bolts so that the light emitting element 103a is arranged at the lower end portion of the projection lens holder 103B.

The pulsed measurement light output from the light emitting element 103 a is beam-shaped by the projection lens 103 b and enters the deflecting mirror 105 . The measurement light is deflected by a deflecting mirror 105 rotated by a motor 160 and transmitted through an optical window 100B. The measurement light is then scanned toward the monitored area.

Reflected light with respect to the measurement light is incident on the deflection mirror 105 through the optical window 100B, and is condensed toward the light receiving element 104a by the light receiving lens 107. The light signal is converted into an electric signal by the light receiving element 14a and sent to the signal processing unit. is entered.

JP 2017-083251 A

In the distance measuring device 100 described in Patent Document 1, a substrate 130d on which a light emitting element 103a is mounted is arranged below a light receiving lens 107. As shown in FIG. Therefore, part of the reflected light deflected by the deflecting mirror 105 and guided to the light receiving element 104a through the light receiving lens 107 is blocked by the substrate 103d. Therefore, there is a problem that the amount of light received by the light receiving element 104a fluctuates depending on the rotation phase of the deflecting mirror 105. FIG.

10(a) and 10(b) show the internal structure of a range finder having the same configuration as the conventional range finder described above. The light-emitting element 103a and a driving circuit for the light-emitting element 103a are mounted on the projecting piece 130d extending from the periphery toward the center of the substrate 103d formed in a substantially annular shape, and the light-emitting element 103a and the driving circuit are mounted on the projecting piece 130d. Wiring patterns for feeder lines and signal lines are provided for the

9A to 9C show, from the left, the rotational phase of the deflection mirror 5, the illuminance distribution on the surface of the light receiving element 104a condensed through the light receiving lens, the projecting piece 130d, and the measurement light. An explanatory diagram showing the positional relationship is shown respectively.

FIG. 9(a) shows the case where the measurement light is emitted from the left side surface of the optical window 100B. FIG. 9B shows the case where the measurement light is emitted from the front of the optical window 100B. FIG. 9(c) shows the case where the measurement light is emitted from the right side surface of the optical window 100B. In the graph shown in FIG. 8, as shown in the total received light power corresponding to the conventional technology, the measurement light is emitted from the left and right side surfaces of the optical window 100B compared to the case where the measurement light is emitted from the front of the optical window 100B. If so, the illuminance of the measurement light will be low.

By the way, the conventional distance measuring device as shown in FIGS. 10 and 11 is mounted, for example, on a transport vehicle for transporting materials at a manufacturing site or the like. It is desired to reduce the size of the distance measuring device so that the distance measuring device can be easily mounted on such a transport vehicle. Therefore, for example, if a light-receiving lens with a short focal length is employed in the device, the height of the device can be reduced. However, reflected light with respect to the measurement light is greatly affected by light shielding by the substrate on which the light emitting element is mounted. This reduces the sensitivity of the light receiving element to reflected light. As a result, there arises a problem that the detectable distance is shortened.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a distance measuring device that suppresses variations in the accuracy of distance measurement depending on the measurement direction and realizes miniaturization of the device.

In order to achieve the above-mentioned object, a first characteristic configuration of a distance measuring device according to the present invention comprises: a light projecting section having a light projecting element; a light receiving section having a light receiving element and a light receiving lens; a scanning unit that scans the emitted measurement light toward the space to be measured and guides reflected light from an object with respect to the measurement light to the light receiving unit; is supported by the light-receiving lens in a posture along the optical axis of the light-receiving lens.

Since the measurement light emitted from the light-projecting part supported by the light-receiving lens travels along the optical axis of the light-receiving lens, the reflected light of the measuring light scanned toward the space to be measured via the scanning part reaches the light-receiving lens. It is properly guided to the light receiving element along the optical axis. As a result, the light-receiving element can take in the reflected light without waste, so that distance measurement can be performed appropriately.

Further, since the light projecting part is supported by the light receiving lens, a separate substrate for supporting the light projecting part is not required, and the reflected light transmitted through the light receiving lens is not blocked by the substrate. This suppresses variations in the amount of received light depending on the scanning direction (that is, measurement direction) of the scanning unit. In other words, variations in the illuminance distribution on the light receiving element are suppressed regardless of the irradiation direction of the measurement light from the scanning unit. As a result, it is possible to suppress variation in the accuracy of distance measurement depending on the measurement direction, and improve the accuracy of distance measurement.

In the second characteristic configuration, in addition to the above-described first characteristic configuration, the light projecting unit includes an attitude adjustment mechanism for adjusting the attitude of the optical axis of the light projecting element, and the attitude adjustment mechanism and the light receiving unit The point is that it is supported by the lens.

The optical axis of the measurement light emitted from the light projecting element may not be aligned with the optical axis of the light receiving lens due to the influence of component tolerances such as support members for the light projecting element and the light receiving lens. Even in such a case, the optical axis of the measurement light can be aligned with the optical axis of the light receiving lens by adjusting the attitude of the optical axis of the light projecting element with the attitude adjustment mechanism.

Thereby, the measuring light travels along the optical axis of the light receiving lens, and the reflected light is properly guided to the light receiving element along the optical axis of the light receiving lens. As a result, the light-receiving element can take in the reflected light without waste, so that distance measurement can be performed appropriately.

In addition to the above-described second characteristic configuration, the third characteristic configuration is that the attitude adjustment mechanism is fixed to a notch formed through the light receiving lens along the optical axis of the light receiving lens, and the projector is fixed to the notch. a holder having a housing for an optical element, a biasing member that supports the light projecting element housed in the housing from below, and a support member that supports the light projecting element from above; and an adjustment member that adjusts the pressing state of the light projecting element by the support member at a plurality of locations around the support member.

The light projecting element accommodated in the accommodation portion of the holder via the urging member is supported from above by the support member, and the light projecting element is pressed using adjustment members provided at a plurality of locations around the support member. The posture of the optical axis of the light projecting element is adjusted by adjusting the pressing force of each adjusting member against the reaction force received from the biasing member. A holder that constitutes the attitude adjustment mechanism is fixed to a notch formed through the light receiving lens, and the light projecting element is accommodated in the holder, so that the light projecting part can be accommodated in the notch formed in the light receiving lens. can be placed.

The fourth characteristic configuration is, in addition to the third characteristic configuration described above, that the light projecting section includes a drive circuit for driving the light projecting element, and the drive circuit is accommodated in the notch. It is in.

By housing the drive circuit in the notch, it is possible to place the light emitting element and the drive circuit close to each other, avoiding the generation of radiation noise and dulling of the signal waveform, which are problems when connecting via a long signal line. can do.

The fifth characteristic configuration is that, in addition to the third or fourth characteristic configuration described above, the adjustment member is fixed with an adhesive to prevent it from loosening.

If the adjustment member is loosened for some reason after the pressing state is adjusted, the posture of the optical axis of the light projecting element changes. By fixing the adjusting member with an adhesive after adjustment, the adjusting member can be prevented from loosening.

In the sixth characteristic configuration, in addition to any one of the third to fifth characteristic configurations described above, the light projecting section is accommodated in a region that does not protrude from the virtual lens surface in the region corresponding to the notch. in the point.

Since the light projecting part does not protrude in the direction of the optical axis of the light receiving lens, it is possible to increase the space utilization efficiency and reduce the size.

The seventh characteristic configuration is, in addition to any one of the first to sixth characteristic configurations, that the light-receiving lens is configured such that the curvature of the entrance surface is larger than the curvature of the exit surface. It is in.

With this configuration, it is possible to efficiently capture reflected light with respect to the measurement light. Therefore, distance measurement can be accurately performed without reducing the amount of light received by the light receiving element.

The eighth characteristic configuration is that, in addition to any one of the first to seventh characteristic configurations, the light projecting element is a photonic crystal surface emitting laser.

When a photonic crystal surface-emitting laser is used as the light projecting element, it is not necessary to use a light projecting lens for beam shaping in the light projecting part, and the light projecting part can be configured more compactly.

As described above, according to the present invention, it is possible to provide a distance measuring device that suppresses variation in the accuracy of distance measurement depending on the direction of measurement and realizes miniaturization of the device. .

1 is a perspective view of a rangefinder; FIG. (a) is a front view of a distance measuring device, and (b) is a plan view of the same. (a) is a cross-sectional view along line BB in FIG. 2(b), and (b) is a cross-sectional view along line CC in FIG. 3(a) It is a sectional view on the AA line of Fig.2 (a). (a) is a plan view of an attitude adjustment mechanism, and (b) is a cross-sectional view of a light projecting part accommodated in a notch of a light receiving lens. It is an exploded perspective view of a posture adjustment mechanism. (a) to (c) are explanatory diagrams of the rotation phase of the deflection mirror 5 and the illuminance distribution on the surface of the light-receiving element condensed via the light-receiving lens. FIG. 2 is an explanatory diagram for comparison between the distance measuring device according to the present invention and a conventional distance measuring device, showing the total received light power on the surface of the light receiving element condensed through the light receiving lens. (a) to (c) show, from the left, the rotational phase of the deflection mirror, the illuminance distribution on the surface of the light receiving element condensed through the light receiving lens, and the positional relationship between the protruding piece (substrate) and the measurement light. It is an explanatory diagram showing. (a) is an explanatory diagram of the internal structure of a conventional distance measuring device, and (b) is an explanatory diagram of a substrate on which a light projecting element is mounted. It is explanatory drawing of the internal structure which shows the other example of the conventional ranging device.

A distance measuring device according to the present invention will be described below with reference to the drawings.
1 and FIGS. 2(a) and (b) show the appearance of the distance measuring device 2, and FIGS. 3(a), (b) and 4 show the internal structure of the distance measuring device 2. ing. The distance measuring device 2 is mounted on a moving object such as an automatic guided vehicle that transports materials at a manufacturing site, for example, and is used as a safety sensor for detecting obstacles on the travel route.

As shown in FIGS. 1 and 2(a) and (b), the distance measuring device 2 includes a substantially rectangular parallelepiped lower casing 2A and an inverted truncated cone-shaped upper casing 2C. It has an optical window 2B through which light passes. A LAN communication cable S1 extends from one side of the back surface of the lower casing 2A, and an input/output cable S2 composed of a plurality of signal lines extends from the other side.

As shown in FIGS. 3A, 3B, and 4, the distance measuring device 2 includes a light projecting section 3 having a light projecting element 3a, and a light receiving section 4 having a light receiving element 4a and a light receiving lens 7. , the measurement light emitted from the light projecting unit 3 is scanned toward the measurement target space through the optical window 2B, and the reflected light from the object existing in the measurement target space that is incident through the optical window 2B is received. and a scanning section 6 leading to the section 4 .

The scanning unit is composed of a motor 60 installed on the inner wall of the top surface of the upper casing 2C, an encoder 61 for detecting the rotation state of the motor 60, and a deflection mirror 5 attached at an angle of 45 degrees to the rotation shaft of the motor 60. 6 is configured. The encoder 61 is composed of a slit pattern printed on a disc that rotates together with the motor 60 and a reflective photosensor that reads the slit pattern. A signal output from the encoder 61 serves as a monitor signal for controlling the rotational speed of the motor 61 and a monitor signal for detecting the scanning angle of the measurement light.

A light projecting element 3 a and a light receiving element 4 a are arranged coaxially with the rotating shaft of the motor 60 . As the light projecting element 3a, a can-type photonic crystal surface emitting laser is used in which an emission window is formed on the top surface of a cylindrical metal casing and terminals extend from the bottom surface. An avalanche photodiode is used as the light receiving element 4a.

A photonic crystal surface-emitting laser uses a photonic crystal, which is a nanostructure whose refractive index changes periodically. is circular and the power is concentrated at its center). A photonic crystal surface-emitting laser is a device capable of obtaining a beam with an extremely narrow divergence angle without using an optical element such as a collimator lens and without degrading the beam quality at a high optical output.

Needless to say, a general-purpose semiconductor laser diode can be used as the light projecting element 3a in addition to the photonic crystal surface emitting laser. In this case, a projection lens is required to collimate the light emitted from the projection element 3a.

The measurement light emitted from the light projecting element 3a enters the deflection mirror 5 along the axis P, is deflected by an angle of 90°, and is scanned into the measurement target space through the optical window 2B. Reflected light from an object existing in the space to be measured enters the directional mirror 5 through the optical window 2B, is deflected by 90° toward the light receiving lens 7, is condensed by the light receiving lens 7, and then enters the light receiving element 4a.

The light-receiving lens 7 has a collar portion 7a supported by a lens holder 70 provided in the lower casing 2A, and is fixed by a fixture 71 covering the upper portion of the collar portion 7a.

When reflected light from an object is incident on the light receiving element 4a, an electrical signal photoelectrically converted by the light receiving element 4a is amplified by the preamplifier and input to the signal processing circuit. In the signal processing circuit, the distance to the reflection point of the object is calculated based on the time from when the measuring light is emitted from the light emitting element 3a until the reflected light is detected by the light receiving element 4a, and the signal from the encoder 61 is calculated. A distance measurement operation is performed to calculate the direction of the reflection point of the object (=the emission direction of the measurement light) based on .

A signal processing circuit for executing the above-described distance measurement calculation is mounted on a circuit board 8 accommodated in the lower casing 2A. Also mounted on the circuit board 8 is a control circuit for the distance measuring device 2 which drives and controls the motor 60 based on the signal from the encoder 61 and controls the light emission of the light projecting element 3a at a predetermined time.

A reference reflector 20b is provided on the side projecting portion 20 of the upper casing 2C in a plan view for correcting the distance measurement value due to part tolerances and aged deterioration (see FIG. 3B). Each time the deflecting mirror 5 rotates once, the reference reflecting plate 20b is irradiated with the measurement light. A correction coefficient for correcting the distance calculation value based on the reflected light from the measurement target space is calculated from the distance calculation value for the reflected light.

As shown in FIGS. 5(a) and 5(b), the light projecting unit 3 having the light projecting element 3a described above is configured such that the optical axis of the light projecting element 3a is aligned with the optical axis P1 of the light receiving lens 7. 7 is supported. The light projecting unit 3 includes an attitude adjustment mechanism 30 that adjusts the attitude of the optical axis of the light projecting element 3a, and is supported by the light receiving lens 7 together with the attitude adjustment mechanism 30. As shown in FIG.

FIG. 6 shows an exploded perspective view of the attitude adjustment mechanism 30. As shown in FIG. The attitude adjustment mechanism 30 is fixed to a notch portion 7h formed through the light receiving lens 7 along the optical axis of the light receiving lens 7. As shown in FIG. The posture adjustment mechanism 30 includes a holder 31 having a housing portion 32 for the light projecting element 3a, an urging member 33 supporting the light projecting element 3a housed in the housing portion 32 from below, and an urging member 33 supporting the light projecting element 3a from above. A support member 34 that supports the light projecting element 3a and an adjustment member 35 that adjusts the pressing state of the light projecting element 3a by the support member 34 at a plurality of locations around the support member 34 are provided.

A configuration of the attitude adjustment mechanism 30 will be specifically described. The notch portion 7h is formed of a through hole having a circular cross section centered on the optical axis P1 of the light receiving lens 7. As shown in FIG. The through hole is formed such that the upper region 7u has a larger diameter than the lower region 7l. The upper region 7u accommodates the cylindrical holder 31 so that the peripheral portion thereof is in contact with the holder 31, and the bottom of the holder 31 is supported by the stepped portion 7s formed between the upper region 7u and the lower region 7l. Three concave portions 38 are formed in the periphery of the holder 31 , and the concave portions 38 are fixed to the light-receiving lens 7 by applying adhesive R for adhesion.

A wave washer or an O-ring, which is an urging member 33, is arranged at the bottom of the accommodating portion 32, a metal casing of the light emitting element 3a is accommodated at the upper portion thereof, and a ring-shaped support member 34 is arranged at the upper portion thereof. It is As the biasing member 33, an elastic member including a leaf spring, a coil spring, or the like can be preferably used.

The annular support member 34 has three radially outward projecting pieces 34O and three radially inwardly projecting inner projecting pieces 34I at intervals of a central angle of 120°. A screw hole 36 for fixing the support member 34 to the holder 31 is formed in the outer protruding piece 34O, and the inner protruding piece 34I is in contact with the peripheral stepped portion 3f formed in the metal casing of the light projecting element 3a. Since the metal casing has a stepped shape in this manner, the posture of the light projecting element 3a can be maintained.

By tightening the screw 35 functioning as the adjustment member 35 to the holder 31 through the three screw holes 36, the metal casing of the light projecting element 3a receives a reaction force from the urging member 33 and changes its attitude. By adjusting the tightening degree of each screw 35, the optical axis of the light projecting element 3a can be aligned with the optical axis P1 of the light receiving lens 7. FIG.

When adjusting the optical axis of the light projecting element 3a, the operator uses a jig equipped with a sensor for driving the light projecting element 3a and detecting the emission direction of the measurement light to move the light projecting element 3a. Monitor the attitude of the optical axis. After adjusting the optical axis of the light projecting element 3a and tightening the adjusting member 35 to the holder 31, if the adjusting member 35 is loosened for some reason, the posture of the optical axis of the light projecting element 3a may change. Therefore, the operator fixes the adjustment member 35 with the adhesive 35r after adjusting the optical axis of the light projecting element 3a. Thereby, loosening of the adjustment member 35 can be prevented.

As the adhesive 35r, an adhesive containing natural rubber, a thermoplastic resin, a thermosetting resin, an ultraviolet curable resin, or an anti-loosening agent can be used as appropriate. By using the adhesive 35r mixed with a black dye or pigment, the reflection of light on the surface of the adhesive 35r can be suppressed, and the generation of noise due to stray light can be greatly reduced. Specifically, when the head of the screw 35 is covered with adhesive 35r over a range extending to the peripheral member, the screw 35 cannot be loosened later using a screwdriver, and the screw 35 can be loosened by external vibration. Since it becomes difficult, it can be fixed more reliably. By covering the edge of the head of the screw 35 and peripheral members with an adhesive 35r, the intended purpose of fixing the screw 35 can be achieved, and the screw 35 can be loosened later using a screwdriver. makes readjustment easier. In this embodiment, Cemedine Super X (registered trademark (manufactured by Cemedine Co., Ltd.)) is used as the adhesive.

In the above example, an example in which the support member 34 is formed in an annular shape has been described, but the annular shape is not essential, and the support member 34 may be configured as individual separated parts. For example, the support members 34 may be arranged at equal intervals in the circumferential direction with respect to the optical axis. In this case, the support member 34 may have functions equivalent to those of the outer projecting piece 34O and the inner projecting piece 34I described above.

In the above example, an example in which the adjusting members 35 are provided at three positions on the holder 31 has been described, but a configuration in which the adjusting members 35 are provided at at least two positions on the holder 31 may be employed. In this case, the adjustment member 35 may be fixed to the holder 31 at one of the two positions.

A substrate 3p having a drive circuit 3e for driving the light projecting element 3a is arranged in the lower region 7l of the through hole, and is connected to the light projecting element 3a by an electric wire through an opening 32h formed at the center of the bottom of the housing portion 32. electrically connected. An electric wire L extending from the board 3p is connected to the circuit board 8 (see FIG. 3(a)). It is possible to avoid the occurrence of radiation noise and blunting of the signal waveform, which are problems when the output of the driving circuit 3e is connected to the light projecting element 3a through a long signal line.

A connection region between the light emitting element 3a and the substrate 3p is sealed with a resin 39 in the lower region 7l of the through hole. In order that the reflected light transmitted through the light-receiving lens 7 is not largely blocked, it is preferable to use, for example, a large electric wire of AWG20 or more, or a flat cable having a wiring pattern on a transparent resin substrate. .

In the example described above, the notch portion 7h is formed by a cylindrical through hole centered on the optical axis P1 of the light receiving lens 7. As shown in FIG. However, the through hole may be formed along the optical axis P1 at a position separated from the optical axis P1 of the light receiving lens 7, that is, parallel to the optical axis P1.

In other words, the light projecting unit 3 may be supported by the light receiving lens 7 in such a manner that the optical axis of the light projecting element 3a is aligned with the optical axis P1 of the light receiving lens 7 . The measurement light emitted from the light projecting unit 3 supported by the light receiving lens 7 travels along the optical axis of the light receiving lens 7 . Therefore, reflected light of the measurement light scanned toward the space to be measured via the scanning unit 6 is properly guided along the optical axis of the light receiving lens 7 to the light receiving element 4a.

Further, since the light projecting section 3 is supported by the light receiving lens 7, a separate substrate for supporting the light projecting section 3 is not required. Therefore, the reflected light transmitted through the light receiving lens 7 is not blocked by the substrate. In other words, variations in the illuminance distribution of the reflected light on the light receiving element 4a are suppressed regardless of the irradiation direction of the measurement light from the scanning unit 6. FIG.

FIGS. 7A, 7B, and 7C show, from the left, the rotation phase of the deflecting mirror 5 and the illuminance distribution on the surface of the light receiving element 4a condensed through the light receiving lens 7. FIG. Figures are shown respectively.

FIG. 7(a) shows the case where the measurement light is emitted from the left side surface of the optical window 2B. FIG. 7(b) shows the case where the measurement light is emitted from the front of the optical window 2B. FIG. 7(c) shows the case where the measurement light is emitted from the right side surface of the optical window 2B. In either case, it is shown that the illuminance of the central portion on the surface of the light receiving element 4a is substantially constant.

As shown in FIG. 8, in comparison with the conventional structure in which the light projecting element 3a is supported by the substrate, the structure of the present invention in which the light projecting element 3a is supported by the light receiving lens 7 is superior to the front and left and right side surfaces of the optical window 2B. A uniform illuminance distribution is obtained and the total power of received light is substantially uniform regardless of which direction the measurement light is emitted from.

It is preferable that the light projecting part 3 is accommodated in a region that does not protrude from the virtual lens surface (indicated by the two-dot chain line in FIG. 5B) in the region corresponding to the notch 7h of the light receiving lens 7 . Since the light projecting part 3 does not protrude in the direction of the optical axis of the light receiving lens 7, the scanning part 6 can be provided directly above the light receiving lens 7, so that the space efficiency can be improved and the size of the distance measuring device 2 can be reduced. .

The virtual lens surface refers to the surface of the light-receiving lens 7 before the notch 7h is formed, and is preferably defined by a smooth curved surface formed by extending the surface of the light-receiving lens 7 in which the notch 7h is formed. be able to. The curvatures of the light-receiving lens 7 and the virtual lens surface can be set within a range in which they do not come into contact with the scanning unit 6 provided directly above. It is sufficient that most of the light projecting section 3 is housed in a region that does not protrude from the virtual lens surface, and even if a portion thereof protrudes from the virtual lens plane, it does not come into contact with the scanning section 6 .

Moreover, the light receiving lens 7 is preferably configured such that the curvature of the incident surface is larger than the curvature of the exit surface.

The light-receiving lens 7 may be configured using optical glass or plastic material, or may use a Fresnel lens.

The above-described embodiment shows an example of the distance measuring device according to the present invention, and it goes without saying that the specific structure of the distance measuring device 1 can be appropriately changed and designed within the scope of the effect of the present invention. The technical scope of the invention is not limited to the above examples.

2: Distance measuring device 2A: Lower casing 2B: Optical window 2C: Upper casing 3: Light projecting part 3a: Light projecting element 3e: Drive circuit 3f: Step part 3p: Substrate 4: Light receiving part 4a: Light receiving element 5: Deflecting mirror 6: Scanning part 7: Light receiving lens 7a: Saliva part 7h: Notch part 8: Circuit board 30: Posture adjustment mechanism 31: Holder 32: Accommodating part 33: Biasing member 34: Supporting member 34O: Outer projecting piece 34I: Inner side Protruding piece 35: adjusting member (screw)
36: screw hole 38: recess 39: resin 60: motor 60a: rotating shaft 61: encoder 70: lens holder 71: fixture R: adhesive S1: communication cable S2: input/output cable

Claims (8)

a light projecting unit including a light projecting element;
a light-receiving unit including a light-receiving element and a light-receiving lens;
a scanning unit that scans the measuring light emitted from the light projecting unit toward the space to be measured and guides the light reflected from the object with respect to the measuring light to the light receiving unit;
with
The light-projecting unit is a distance measuring device supported by the light-receiving lens in a posture in which the optical axis of the light-projecting element is aligned with the optical axis of the light-receiving lens. 2. A distance measuring apparatus according to claim 1, wherein said light projecting unit has an attitude adjusting mechanism for adjusting the attitude of the optical axis of said light projecting element, and is supported by said light receiving lens together with said attitude adjusting mechanism. The attitude adjustment mechanism is
a holder that is fixed to a notch formed through the light-receiving lens along the optical axis of the light-receiving lens and has a housing for the light projecting element;
a biasing member that supports the light projecting element housed in the housing from below;
a support member that supports the light projecting element from above;
3. The distance measuring device according to claim 2, further comprising an adjustment member for adjusting a pressing state of said light projecting element by said support member at a plurality of positions around said support member. The light projecting unit includes a drive circuit that drives the light projecting element,
4. A distance measuring device according to claim 3, wherein said drive circuit is accommodated in said notch. 5. The distance measuring device according to claim 3, wherein said adjusting member is fixed with an adhesive to prevent it from loosening. 6. The distance measuring device according to claim 3, wherein the light projecting section is accommodated in a region that does not protrude from the virtual lens surface in the region corresponding to the notch. 7. The distance measuring device according to claim 1, wherein the light receiving lens is constructed such that the curvature of the entrance surface is larger than the curvature of the exit surface. 8. The distance measuring device according to claim 1, wherein said light projecting element is a photonic crystal surface emitting laser.

Images