Stray light suppression structure and laser ranging device

Abstract

To provide a stray light suppression structure capable of preventing generation of stray light caused by laser light emitted from a lens barrel.SOLUTION: A stray light suppression structure (A) is provided, comprising opaque stray light suppression members (16) provided with through-holes for inserting lens barrels (14, 15) and configured to generate elastic force and prevent laser light from transmitting therethrough. End faces of the stray light suppression members (16) with openings of the through-holes are pressed against a rear surface of a glass panel (5) to be in contact.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a stray light prevention structure and a laser distance measuring device. [Background technology]

[0002] A laser distance measuring device is a device that acquires colored 3D information based on an image captured by a camera and a 3D point cloud measured using a laser beam. In a laser distance measuring device, color information is assigned to the position where the 3D point is acquired by aligning the optical axis of the laser beam with a preset position relative to the center of the captured image.

[0003] On the other hand, in a laser distance measuring device, it is necessary to prevent the occurrence of so-called stray light, in which the laser light emitted from the light transmitting unit is reflected inside the housing of the device and incident on the light receiving unit. As a conventional technology for preventing the occurrence of stray light, for example, there is a laser distance measuring device described in Patent Document 1.

[0004] The laser distance measuring device described in Patent Document 1 includes a reflecting member having a measurement light reflecting portion that reflects measurement light reflected by an external object toward a light receiving portion, and a light-shielding portion provided on the surface of the reflecting member at least in part of the boundary between the incident light reflecting portion and the measurement light reflecting portion. The light-shielding portion can reduce the generation of stray light. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5911987 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the conventional technology described in Patent Document 1, stray light is blocked by a light-shielding section provided at the boundary between the incident light reflecting section and the measurement light reflecting section of the lens barrel, which poses the problem of not being able to prevent the generation of stray light caused by the laser light emitted from the lens barrel. For example, in a laser distance measuring device, the laser light transmitting section is generally configured to include a light emitting element housed in a lens barrel within a housing, and a glass panel is provided between the lens barrel within the housing and the outside of the housing, so that there is a possibility that part of the laser light emitted from the lens barrel is reflected on the surface of the glass panel and enters the light receiving section.

[0007] The present disclosure is intended to solve the above-mentioned problems, and aims to provide a stray light prevention structure that can prevent the generation of stray light caused by laser light emitted from a lens barrel. [Means for solving the problem]

[0008] The stray light prevention structure of the present disclosure is a stray light prevention structure for a laser distance measuring device that includes a housing, at least one of a lens barrel for transmitting or receiving laser light, and a panel member arranged between the housing and the outside, and measures the distance to an object by receiving laser light that is irradiated from the lens barrel and reflected by the object, and includes a stray light prevention member that has a through hole portion into which the lens barrel is inserted and generates an elastic force, and the end face of the stray light prevention member where the through hole portion is open is pressed against and makes contact with the back surface of the panel member. [Effects of the Invention]

[0009] According to the present disclosure, there is provided an opaque stray light prevention member that has a through-hole into which a lens barrel is inserted, generates elastic force, and is opaque to laser light, and the end face of the stray light prevention member where the through-hole is open is pressed against and in contact with the back surface of a panel member. This prevents the laser light emitted from the lens barrel from being reflected by the surface of the panel member and propagating to the light-receiving lens barrel, so the stray light prevention structure according to the present disclosure can prevent the generation of stray light caused by the laser light emitted from the lens barrel. [Brief explanation of the drawings]

[0010] [Figure 1] 1A and 1B are perspective views showing a laser distance measuring device according to the first embodiment. [Figure 2] 2A and 2B are diagrams showing an outline of a stray light prevention structure according to the first embodiment. [Figure 3] 3A, 3B, and 3C are diagrams showing the structure of the stray light prevention structure according to the first embodiment. [Figure 4] 4A and 4B are diagrams showing a structure of Modification 1 of the stray light prevention structure according to Embodiment 1. FIG. [Figure 5] 5A and 5B are diagrams showing an overview of a first modification of the stray light prevention structure according to the first embodiment. [Figure 6] 6A and 6B are front views showing the lens barrel in the housing through a glass panel. [Figure 7] 7A and 7B are bottom perspective views showing the lens barrel in the housing through a glass panel. [Figure 8] 8A and 8B are side perspective views showing the lens barrel in the housing through a glass panel. [Figure 9] 9A, 9B, and 9C are diagrams showing an outline of a stray light prevention structure according to the second embodiment. [Figure 10] 10A, 10B, and 10C are diagrams showing an outline of a modification of the stray light prevention structure according to the second embodiment. [Figure 11] 11A, 11B, and 11C are diagrams showing an outline of a stray light prevention structure according to the third embodiment. [Figure 12] 12A, 12B, 12C, and 12D are diagrams showing an outline of a modification of the stray light prevention structure according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Embodiment 1 (Outline of laser distance measuring device) A laser ranging device with a stray light prevention structure according to a first embodiment will be described with reference to FIGS. 1A and 1B. The laser ranging device is a device that irradiates a space with laser light and measures the distance to an object based on a received signal obtained by receiving the laser light reflected by the object in the space. The laser ranging device may also be a device that acquires colored three-dimensional information based on an image captured by a camera and a three-dimensional point cloud measured using laser light, namely, a camera equipped with a three-dimensional laser scanner function. In the following description, the laser ranging device will be described as a device that acquires colored three-dimensional information based on an image captured by a camera and a three-dimensional point cloud measured using laser light.

[0012] 1A is a front perspective view showing the appearance of a laser distance measuring device 1 according to embodiment 1 as seen from an oblique front direction. FIG. 1B is a rear perspective view showing the appearance of the laser distance measuring device 1 as seen from an oblique rear direction. In FIGS. 1A and 1B, the laser distance measuring device 1 includes a main body 2, a measurement housing 3, and a base 4. A glass panel 5 is attached to the measurement surface of the measurement housing 3.

[0013] The main body 2 rotatably supports the measurement housing 3 and is rotatably supported by the base 4. The main body 2 houses, for example, a drive unit, an input interface, an information processing unit, an output interface, and a communication unit, which are not shown in FIG. 1 . The drive unit includes a drive unit for rotating the measurement housing 3 and a drive unit for rotating itself supported by the base 4. The input interface is, for example, an interface for acquiring information measured by the measurement housing 3. The information processing unit processes the information acquired from the measurement housing 3. The output interface is an interface for outputting three-dimensional information that is the result of information processing by the information processing unit. The communication unit transmits the three-dimensional information output via the output interface to an external device, for example, a LAN (Local Area Network) communication device.

[0014] The measurement housing 3 is a housing that houses a measurement system including, for example, a camera and a laser scanner, which are not shown in FIG. 1 . The camera captures images of the outside of the measurement housing 3. The laser scanner measures the distance to an object by sending and receiving laser light. For example, the laser scanner is capable of laser distance measurement over a wide range, day or night. The measurement housing 3 is rotatably supported on the side of the main body 2. The laser distance measuring device 1 is also capable of laser scanning while rotating the main body 2 or the measurement housing 3. Furthermore, a glass panel 5 is attached between the measurement housing 3 and the outside. The laser scanner sends and receives laser light through the glass panel 5, and the camera captures images of the outside through the glass panel 5.

[0015] The base 4 is provided below the main body 2 and rotatably supports the main body 2. The laser distance measuring device 1 is attached to a measurement environment such as outdoors via the base 4. In the laser distance measuring device 1, the main body 2 can be rotated left and right relative to the base 4, for example, 360° endlessly, and the measurement housing 3 can be rotated up and down relative to the main body 2, for example, ±90°. In addition, by installing the base 4 in a suspended state, the laser distance measuring device 1 can also be suspended from a ceiling.

[0016] The glass panel 5 is a panel member disposed between the measurement housing 3 and the outside, and is made of a material that allows, for example, imaging by a camera and that allows laser light to pass through. From the viewpoint of design and the like, the rear surface of the glass panel 5 is opaque except for the area including the portion facing the camera lens and the portion in contact with the end face of the stray light prevention member according to embodiment 1. For example, the area other than these areas is coated with an opaque coating such as black.

[0017] The laser distance measuring device 1 is provided with a stray light prevention member in the measurement housing 3. The stray light prevention member prevents the laser light emitted from the lens barrel provided in the measurement housing 3 from propagating to the rear side of the glass panel 5. This allows the laser distance measuring device 1 to prevent the generation of stray light caused by the laser light emitted from the lens barrel. The stray light prevention structure according to the first embodiment will be described below.

[0018] (Overview of stray light prevention structure) 2A is a rear perspective view showing the appearance of the laser distance measuring device 1 as seen from an oblique direction behind, and shows the position of the stray light prevention structure A in the measurement housing 3. In FIG. 2A, the stray light prevention structure A is disposed in the space within the housing corresponding to the area surrounded by the dashed line indicated by the arrow in the measurement housing 3. FIG. 2B is a side view showing the configuration of the stray light prevention structure A according to the first embodiment. As shown in FIG. 2B, a glass panel 5 is attached between the measurement housing 3 and the outside, and a camera 11 and a laser unit 12 are disposed from inside the measurement housing 3 facing the rear surface of the glass panel 5.

[0019] The imaging range of camera 11 is the external area in front of it through glass panel 5. As shown in FIG. 2B, camera 11 is disposed alongside laser unit 12. For example, the image captured by camera 11 includes the object to be measured by laser unit 12.

[0020] Laser unit 12 includes a lens barrel 14 and a lens barrel 15. Lens barrel 14 is a lens barrel for transmitting laser light and is an optical system that guides the laser light generated by a light-emitting element (not shown in Fig. 2B) to the outside. Lens barrel 15 is a lens barrel for receiving laser light and is an optical system that guides the laser light that has been reflected or scattered by an object in external space and returned to laser distance measuring device 1 to a light-receiving element (not shown in Fig. 2B). In order to prevent the laser light emitted from the lens barrel 14 from reaching the lens barrel 15 directly and to allow the lens barrel 15 to efficiently receive the reflected light that is reflected by the target object and returned at various angles, the height of the lens barrel 15 for receiving light is made higher than that of the lens barrel 14 for transmitting light.

[0021] In the stray light prevention structure A, a stray light prevention member 16 is attached to the lens barrel 14 and the lens barrel 15. The stray light prevention member 16 attached to the lens barrel 14 is a cylindrical member having a through-hole into which the lens barrel 14 is inserted. The stray light prevention member 16 attached to the lens barrel 15 is also a cylindrical member having a through-hole into which the lens barrel 15 is inserted. The stray light prevention member 16 is a member that generates elastic force. Furthermore, as shown in FIG. 2B , the end face of the stray light prevention member 16 where the through-hole is open is pressed against and in contact with the rear surface of the glass panel 5 by the elastic force. This prevents the laser light emitted from the lens barrel 14 from reflecting off the surface of the glass panel 5 and propagating to the lens barrel 15, so the stray light prevention structure A can prevent the generation of stray light caused by the laser light emitted from the lens barrel 14.

[0022] (Example 1 of stray light prevention structure) 3A is a side view showing laser unit 12 to which stray light prevention member 16 according to embodiment 1 is attached. Stray light prevention member 16 is a tubular member composed of cylindrical portion 161 and bellows portion 162, each of which is connected by a through-hole. Cylindrical portion 161 is a tubular portion with bellows portion 162 formed at one end. Bellows portion 162 is a cylindrical member that generates elastic force. Stray light prevention member 16 is made of a material that is opaque to the laser light irradiated from lens barrel 14. Stray light prevention member 16 is attached by inserting lens barrels 14, 15 into the through-hole from the cylindrical portion 161 side.

[0023] The height of stray light prevention member 16 should be higher than barrels 14, 15 and larger than the distance from the base of barrels 14, 15 in laser unit 12 to the rear surface of glass panel 5. As a result, when barrels 14, 15 are inserted into the through-holes of stray light prevention member 16 and stray light prevention member 16 is attached to the inside of measurement housing 3, bellows portion 162 is in a contracted state. In the contracted state, a reaction force occurs in bellows portion 162 to return to its original length, and this reaction force becomes an elastic force, so that the end face of bellows portion 162 is pressed against the rear surface of glass panel 5 and comes into contact with it. At this time, the lens barrels 14 and 15 are covered by the glass panel 5 and the stray light prevention member 16, so that the laser light emitted from the lens barrel 14 is prevented from being reflected on the surface of the glass panel 5 and propagating to the lens barrel 15.

[0024] Although the case where stray light prevention member 16 is attached to lens barrel 14 and lens barrel 15 has been shown, stray light prevention structure A is not limited to this. For example, stray light prevention member 16 only needs to be attached to at least one of lens barrel 14 or lens barrel 15, and so may be attached only to lens barrel 14 or only to lens barrel 15. Even with this structure, lens barrel 14 or lens barrel 15 is covered by glass panel 5 and stray light prevention member 16, so that the laser light emitted from lens barrel 14 is prevented from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0025] Furthermore, stray light prevention member 16 may be fixed to laser unit 12, which is provided with lens barrels 14 and 15. For example, a screw fastening piece is provided at the cylindrical end of stray light prevention member 16, and stray light prevention member 16 is fixed to laser unit 12 by screw fastening. This configuration makes it possible to prevent stray light prevention member 16 from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0026] Also, stray light prevention member 16 may be fixed to the rear surface of glass panel 5. For example, the cylindrical end of stray light prevention member 16 is fixed to the rear surface of glass panel 5 with an adhesive. By configuring it in this manner, it is possible to prevent stray light prevention member 16 from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15. When the end of the cylinder is fixed to the rear surface of the glass panel 5, the end of the cylinder is pressed against and comes into contact with the rear surface of the glass panel 5. This prevents the laser light emitted from the lens barrel 14 from being reflected on the surface of the glass panel 5 and propagating to the lens barrel 15. When the end of the cylinder is fixed to the rear surface of the glass panel 5 in this way, the stray light prevention member 16 does not need to include an elastic member.

[0027] Furthermore, stray light prevention member 16 may be sandwiched between laser unit 12, on which lens barrels 14 and 15 are provided, and the rear surface of glass panel 5. For example, stray light prevention member 16 is sandwiched and fixed between laser unit 12 and glass panel 5 only by the reaction force of bellows portion 162 in a contracted state. Even with this configuration, it is possible to prevent stray light prevention member 16 from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0028] (Adjusting the angle of the telescope tube) By rotating the laser unit 12 around the axis 13, the angles of the lens barrels 14 and 15 can be adjusted up and down. 3B shows the case where the angles of the lens barrels 14 and 15 are adjusted downward. As shown in FIG. 3B, the angles of the lens barrels 14 and 15 can be adjusted downward by rotating the laser unit 12 around the axis 13 in the direction of arrow B. At this time, the stray light prevention member 16 attached to the upper lens barrel 14 in FIG. 3B is contracted as shown by the arrow, and the stray light prevention member 16 attached to the lower lens barrel 15 is extended as shown by the arrow. Even in these states, the end faces of each stray light prevention member 16 are pressed against the rear surface of the glass panel 5 due to the elastic force generated by the expansion and contraction of the bellows portion 162.

[0029] 3C shows the case where the angles of the lens barrels 14 and 15 are adjusted upward. As shown in FIG. 3C, the angles of the lens barrels 14 and 15 can be adjusted upward by rotating the laser unit 12 around the axis 13 in the direction of the arrow C. At this time, the stray light prevention member 16 attached to the upper lens barrel 14 in FIG. 3C is extended as shown by the arrow, and the stray light prevention member 16 attached to the lower lens barrel 15 is retracted as shown by the arrow. Even in these states, the end faces of the stray light prevention members 16 are pressed against the rear surface of the glass panel 5 due to the elastic force generated by the expansion and contraction of the bellows portion 162.

[0030] (Opening diameter setting) Furthermore, stray light prevention member 16 may adjust the angles of barrels 14, 15 within a preset adjustment range, or may have a through-hole portion with an opening diameter that prevents barrels 14, 15 from interfering with the inner wall of bellows portion 162. By configuring in this manner, it is possible to prevent stray light prevention member 16 from restricting the angle adjustment of barrels 14, 15. Since the angle by which laser unit 12 can be rotated around axis 13 is predetermined, the angle of lens barrels 14, 15 in the vertical direction can be adjusted within an adjustment range corresponding to this rotation angle. Furthermore, by moving laser unit 12 in the horizontal direction, the angle of lens barrels 14, 15 can be adjusted in the left-right direction. For example, since the angle by which laser unit 12 can be moved horizontally is predetermined, lens barrels 14, 15 can be adjusted in the left-right direction within an adjustment range corresponding to this angle.

[0031] For example, the diameter of the lens barrel is D, the initial diameter of the through-hole is d0, and the angle adjustment range of the lens barrel is θ MAX The length of the lens barrel is L. When the angle of the lens barrel is adjusted, one end (top end) of the lens barrel is displaced from the center of the through-hole. Angle adjustment range θ MAX The maximum deviation amount δ can be expressed by the following formula (1). δ=L tan(θ MAX ) (1)

[0032] When the lens barrel is angle-adjusted inside the through-hole, the minimum opening diameter d that does not interfere with the inner wall of the through-hole is determined by the diameter D of the lens barrel and the maximum deviation δ. min can be expressed by the following formula (2). d min =D+2·δ (2)

[0033] If the initial diameter d0 of the through hole is set, d0 is d min It is enough if d0 is equal to or greater than d min If it is smaller than this, it is necessary to widen the opening diameter of the through-hole. By this procedure, it is possible to find the minimum opening diameter that can be adjusted without the lens barrel interfering with the inner wall of the through-hole.

[0034] (Example 2 of stray light prevention structure) Although the stray light prevention member 16 has been shown to be attached so that the end face of the bellows portion 162 comes into contact with the rear surface of the glass panel 5, it may also be attached so that the end face of the cylindrical portion 161 comes into contact with the rear surface of the glass panel 5. Fig. 4A is a perspective view showing an outline of the attachment of stray light prevention member 16 to laser unit 12, and shows stray light prevention member 16 attached to lens barrels 14, 15 with bellows portion 162 facing laser unit 12. Fig. 4B is a side view showing laser unit 12 on which stray light prevention member 16 is attached so that the end face of cylindrical portion 161 contacts the back surface of glass panel 5.

[0035] 4A and 4B, even when stray light prevention member 16 is attached, bellows portion 162 remains in a contracted state. A reaction force that tries to return bellows portion 162 to its original length from the contracted state occurs, and this reaction force becomes an elastic force, so that the end face of cylindrical portion 161 is pressed against and comes into contact with the rear surface of glass panel 5. At this time, lens barrels 14 and 15 are covered by glass panel 5 and stray light prevention member 16, and therefore, the laser light emitted from lens barrel 14 is prevented from propagating to lens barrel 15 on the rear surface side of glass panel 5. Furthermore, even if stray light prevention member 16 is attached as shown in FIGS. 4A and 4B, the angles of lens barrels 14 and 15 can be adjusted up and down by rotating laser unit 12 around axis 13.

[0036] 5A shows a case where the angles of the lens barrels 14 and 15 are adjusted downward. As shown in FIG. 5A, the angles of the lens barrels 14 and 15 can be adjusted downward by rotating the laser unit 12 around the axis 13 in the direction of arrow B. At this time, the stray light prevention member 16 attached to the lens barrel 14 on the upper side in FIG. 5A is contracted as shown by the arrow, and the stray light prevention member 16 attached to the lens barrel 15 on the lower side is extended as shown by the arrow. Even in these states, the end face of the cylindrical portion 161 of each stray light prevention member 16 is pressed against the back surface of the glass panel 5 due to the elastic force generated by the expansion and contraction of the bellows portion 162.

[0037] 5B shows the case where the angles of the lens barrels 14 and 15 are adjusted upward. As shown in FIG. 5B, the angles of the lens barrels 14 and 15 can be adjusted upward by rotating the laser unit 12 around the axis 13 in the direction of the arrow C. At this time, the stray light prevention member 16 attached to the upper lens barrel 14 in FIG. 5B is extended as shown by the arrow, and the stray light prevention member 16 attached to the lower lens barrel 15 is contracted as shown by the arrow. Even in these states, the end face of the cylindrical portion 161 of each stray light prevention member 16 is pressed against the back surface of the glass panel 5 due to the elastic force generated by the expansion and contraction of the bellows portion 162.

[0038] Furthermore, the through-hole portion of stray light prevention member 16 may be configured to have an opening diameter that prevents barrels 14, 15 from interfering with the inner wall of cylindrical portion 161 even when the angles of barrels 14, 15 are adjusted within a preset adjustment range. The opening diameter of the through-hole portion is determined by calculation using, for example, the above formulas (1) and (2). Even with this configuration, it is possible to prevent stray light prevention member 16 from restricting the angle adjustment of barrels 14, 15.

[0039] (Blinding effect of stray light prevention material) Glass panel 5 is formed opaque at least in an area on the back surface thereof except for an area including a portion that contacts the end face of stray light prevention member 16. For example, glass panel 5 is coated with an opaque coating such as black, except for an area on the back surface thereof facing camera 11 and an area on the back surface thereof including a portion that contacts the end face of stray light prevention member 16. This makes it possible to prevent the interior of measurement housing 3 from being seen through glass panel 5.

[0040] Fig. 6A is a front view showing the glass panel 5 facing the lens barrels 14, 15 with the stray light prevention member 16 attached, as viewed from the outside. Fig. 6B is a front view showing the glass panel 5 facing the lens barrels 14, 15 without the stray light prevention member 16 attached, as viewed from the outside. As shown in Figs. 6A and 6B, an opaque coating layer 5A is formed on the glass panel 5 to prevent the interior of the measurement housing 3 from being seen. In addition, in the portion of the opaque coating layer 5A on the back side of the glass panel 5 facing the lens barrels 14, 15, an oval-shaped transparent region 5B is formed where the opaque coating layer 5A has been removed. When the transparent area 5B of the glass panel 5 is viewed from the front, the lens barrels 14 and 15 inside the measurement housing 3 can be seen from the outside through the transparent area 5B, regardless of whether the stray light prevention member 16 is attached or not.

[0041] FIG. 7A is a bottom perspective view showing the glass panel 5 facing the lens barrels 14, 15 with the stray light prevention member 16 attached, as viewed from the outside. FIG. 7B is a bottom perspective view showing the glass panel 5 facing the lens barrels 14, 15 without the stray light prevention member 16 attached, as viewed from the outside. As shown in FIG. 7B, when the transparent region 5B of the glass panel 5 is viewed from below, if the stray light prevention member 16 is not attached, the lens barrels 14, 15 and their surrounding configuration inside the measurement housing 3 can be seen from the outside through the transparent region 5B. On the other hand, if the stray light prevention member 16 is attached, only the lens barrels 14, 15 and the stray light prevention member 16 can be seen from the outside through the transparent region 5B, and the other configuration inside the measurement housing 3 is hidden from the outside.

[0042] FIG. 8A is a side perspective view showing the glass panel 5 facing the lens barrels 14, 15 with the stray light prevention member 16 attached, as viewed from the outside. FIG. 8B is a side perspective view showing the glass panel 5 facing the lens barrels 14, 15 without the stray light prevention member 16 attached, as viewed from the outside. As shown in FIG. 8B, when the transparent region 5B of the glass panel 5 is viewed from the side, if the stray light prevention member 16 is not attached, the lens barrels 14, 15 and their surrounding components inside the measurement housing 3 can be seen from the outside through the transparent region 5B, as in FIG. 7B. On the other hand, if the stray light prevention member 16 is attached, only the lens barrels 14, 15 and the stray light prevention member 16 can be seen from the outside through the transparent region 5B, and the other components inside the measurement housing 3 are hidden from the outside. By attaching the stray light prevention member 16 in this manner, it is possible to prevent the inside of the measurement housing 3 from being seen through the glass panel 5.

[0043] As described above, stray light prevention structure A according to embodiment 1 has through-holes into which lens barrels 14 and 15 are inserted, and includes stray light prevention member 16 that generates elastic force, and the end face where the through-holes of stray light prevention member 16 are open is pressed against and in contact with the rear surface of glass panel 5. This prevents the laser light emitted from lens barrel 14 from propagating to the rear surface side of glass panel 5, so that stray light prevention structure A can prevent the generation of stray light caused by the laser light emitted from lens barrel 14.

[0044] In the stray light prevention structure A according to the first embodiment, the stray light prevention member 16 is provided on at least one of the lens barrels 14, 15 for transmitting or receiving laser light. This prevents the laser light emitted from the lens barrel 14 from propagating to the rear surface of the glass panel 5, and therefore the stray light prevention structure A can prevent the generation of stray light caused by the laser light emitted from the lens barrel 14.

[0045] In the stray light prevention structure A according to the first embodiment, stray light prevention member 16 is a cylindrical member having bellows portion 162 that generates an elastic force and cylindrical portion 161 at one end of which bellows portion 162 is formed. The elastic force presses the open end face of stray light prevention member 16 against and into contact with the rear surface of glass panel 5, thereby preventing laser light emitted from lens barrel 14 from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0046] In the stray light prevention structure A according to the first embodiment, the glass panel 5 is formed opaque at least in an area on the back surface thereof except for a portion that contacts the end face of the stray light prevention member 16. This makes it possible to prevent the interior of the measurement housing 3 from being seen through the glass panel 5.

[0047] In the stray light prevention structure A according to the first embodiment, the stray light prevention member 16 has a through-hole with an opening diameter that prevents the lens barrels 14, 15 from interfering with the inner wall even when the angles of the lens barrels 14, 15 are adjusted within a preset adjustment range. This prevents the stray light prevention member 16 from restricting the angle adjustment of the lens barrels 14, 15.

[0048] In the stray light prevention structure A according to the first embodiment, the stray light prevention member 16 is fixed to the laser unit 12 provided with the lens barrels 14 and 15. This makes it possible to prevent the stray light prevention member 16 from shifting when the laser unit 12 is moved to adjust the angle of the lens barrel 14 or 15.

[0049] In the stray light prevention structure A according to the first embodiment, the stray light prevention member 16 is fixed to the rear surface of the glass panel 5. This prevents the stray light prevention member 16 from shifting when the laser unit 12 is moved to adjust the angle of the lens barrel 14 or the lens barrel 15. Furthermore, even if stray light prevention member 16 does not include an elastic member, by fixing it to the rear surface of glass panel 5, the cylindrical end is pressed against and in contact with the rear surface of glass panel 5. As a result, stray light prevention structure A prevents laser light emitted from lens barrel 14 from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0050] In the stray light prevention structure A according to the first embodiment, the stray light prevention member 16 is sandwiched between the laser unit 12 provided with the lens barrels 14 and 15 and the rear surface of the glass panel 5. This prevents the stray light prevention member 16 from shifting when the angle of the lens barrel 14 or 15 is adjusted by moving the laser unit 12.

[0051] The laser distance measuring device 1 according to the first embodiment includes a measurement housing 3, lens barrels 14 and 15, a glass panel 5 arranged between the measurement housing 3 and the outside, and a stray light prevention structure A. The stray light prevention structure A makes it possible to provide a laser distance measuring device 1 in which the generation of stray light caused by the laser light emitted from the lens barrel 14 is prevented.

[0052] Embodiment 2 In the first embodiment, the bellows portion that generates the elastic force is a part of the stray light prevention member, but in the second embodiment, a case where the entire stray light prevention member is an elastic member will be described.

[0053] 9A is a side view showing laser unit 12 to which stray light prevention member 16A according to embodiment 2 is attached. Laser unit 12 to which stray light prevention member 16A is attached is provided in measurement housing 3 included in laser distance measuring device 1 according to embodiment 2. As shown in FIG. 9A, stray light prevention member 16A is a bellows-shaped tube that generates elastic force. Stray light prevention member 16A is made of a material that does not transmit laser light emitted from lens barrel 14. Stray light prevention member 16A is attached by inserting lens barrels 14, 15 into the through-hole portion of the bellows-shaped tube.

[0054] The height of stray light prevention member 16A, like stray light prevention member 16, should be higher than barrels 14, 15 and larger than the distance from the base of barrels 14, 15 in laser unit 12 to the rear surface of glass panel 5. As a result, when barrels 14, 15 are inserted into the through-holes and stray light prevention member 16A is attached inside measurement housing 3, the entire member is in a contracted state. In the contracted state, stray light prevention member 16A generates a reaction force that tries to return it to its original length, and this reaction force becomes an elastic force, so that the end face of stray light prevention member 16A is pressed against and comes into contact with the rear surface of glass panel 5. At this time, lens barrels 14 and 15 are covered by glass panel 5 and stray light prevention member 16A, so that the laser light emitted from lens barrel 14 is prevented from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0055] Although the case where stray light prevention member 16A is attached to lens barrel 14 and lens barrel 15 has been shown, stray light prevention structure A according to embodiment 2 is not limited to this. For example, stray light prevention member 16A only needs to be attached to at least one of lens barrel 14 or lens barrel 15, and so it may be attached only to lens barrel 14 or only to lens barrel 15. Even with this structure, lens barrel 14 or lens barrel 15 is covered by glass panel 5 and stray light prevention member 16A, so that the laser light emitted from lens barrel 14 is prevented from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0056] Also, stray light prevention member 16A may be fixed to laser unit 12 provided with lens barrels 14 and 15. For example, a screw fastening piece is provided at the end of stray light prevention member 16A, and stray light prevention member 16A is fixed to laser unit 12 by screw fastening. With this configuration, it is possible to prevent stray light prevention member 16A from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0057] Also, stray light prevention member 16A may be fixed to the rear surface of glass panel 5. For example, an end of stray light prevention member 16A is fixed to the rear surface of glass panel 5 with an adhesive. This configuration makes it possible to prevent stray light prevention member 16A from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0058] Furthermore, stray light prevention member 16A may be sandwiched between laser unit 12, on which lens barrels 14 and 15 are provided, and the rear surface of glass panel 5. For example, stray light prevention member 16A is sandwiched and fixed between laser unit 12 and glass panel 5 only by the reaction force in the contracted state. Even with this configuration, it is possible to prevent stray light prevention member 16A from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0059] (Adjusting the angle of the telescope tube) By rotating the laser unit 12 around the axis 13, the angles of the lens barrels 14 and 15 can be adjusted up and down. 9B shows the case where the angles of the lens barrels 14 and 15 are adjusted downward. As shown in FIG. 9B, the angles of the lens barrels 14 and 15 can be adjusted downward by rotating the laser unit 12 around the axis 13 in the direction of arrow B. At this time, the stray light prevention member 16A attached to the upper lens barrel 14 in FIG. 9B is contracted as shown by the arrow, and the stray light prevention member 16A attached to the lower lens barrel 15 is extended as shown by the arrow. Even in these states, the end faces of each stray light prevention member 16A are pressed against the rear surface of the glass panel 5 due to the elastic force caused by the overall expansion and contraction.

[0060] 9C shows the case where the angles of the lens barrels 14 and 15 are adjusted upward. As shown in FIG. 9C, the angles of the lens barrels 14 and 15 can be adjusted upward by rotating the laser unit 12 around the axis 13 in the direction of the arrow C. At this time, the stray light prevention member 16A attached to the upper lens barrel 14 in FIG. 9C is extended as shown by the arrow, and the stray light prevention member 16A attached to the lower lens barrel 15 is contracted as shown by the arrow. Even in these states, the end faces of each stray light prevention member 16A are pressed against the rear surface of the glass panel 5 due to the elastic force caused by the overall expansion and contraction.

[0061] (Opening diameter setting) Furthermore, stray light prevention member 16A may adjust the angles of barrels 14, 15 within a preset adjustment range, or may have through-holes with an opening diameter that prevents barrels 14, 15 from interfering with the inner walls of the through-holes. This configuration prevents stray light prevention member 16A from restricting the angle adjustment of barrels 14, 15. Since the angle by which laser unit 12 can be rotated around axis 13 is predetermined, the vertical angle of lens barrels 14, 15 can be adjusted within an adjustment range corresponding to this rotation angle. In addition, by moving laser unit 12 in the horizontal direction, the angle of lens barrels 14, 15 can be adjusted left and right. For example, since the angle by which laser unit 12 can be moved horizontally is predetermined, lens barrels 14, 15 can be adjusted left and right within an adjustment range corresponding to this angle. For example, the opening diameter of the through-hole portion may be determined according to the above formula (1) and formula (2).

[0062] (Variation) The stray light prevention member may be an elastic sponge member (cell foam). 10A is a side view showing laser unit 12 equipped with stray light prevention member 16B, which is a modified example of the stray light prevention member according to embodiment 2. Laser unit 12 equipped with stray light prevention member 16B is provided in measurement housing 3 included in laser distance measuring device 1 according to embodiment 2. As shown in FIG. 10A, stray light prevention member 16B is a sponge member that generates elastic force. Stray light prevention member 16B is made of a foamed material that does not transmit laser light irradiated from lens barrel 14. Stray light prevention member 16B is attached by inserting lens barrels 14, 15 into the through-hole portion.

[0063] The height of stray light prevention member 16B, like stray light prevention member 16, should be higher than barrels 14, 15 and larger than the distance from the base of barrels 14, 15 in laser unit 12 to the rear surface of glass panel 5. As a result, when barrels 14, 15 are inserted into the through-holes and stray light prevention member 16A is attached inside measurement housing 3, the entire member is in a contracted state. In the contracted state, stray light prevention member 16B generates a reaction force that tries to return it to its original length, and this reaction force becomes an elastic force, so that the end face of stray light prevention member 16B is pressed against and comes into contact with the rear surface of glass panel 5. At this time, lens barrels 14 and 15 are covered by glass panel 5 and stray light prevention member 16B, so that the laser light emitted from lens barrel 14 is prevented from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0064] Although the case has been shown in which lens barrel 14 and lens barrel 15 are attached by being inserted into two through-holes formed in stray light prevention member 16B, the present invention is not limited to this. For example, stray light prevention member 16B may be a sponge member having only one through-hole, and stray light prevention member 16B may be attached to at least one of lens barrel 14 or lens barrel 15. As a result, stray light prevention member 16B may be attached only to lens barrel 14, or only to lens barrel 15. Even with this structure, lens barrel 14 or lens barrel 15 is covered by glass panel 5 and stray light prevention member 16B, so that the laser light emitted from lens barrel 14 is prevented from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0065] Furthermore, stray light prevention member 16B may be fixed to laser unit 12 provided with lens barrels 14 and 15. For example, a screw fastening piece may be provided at the end of stray light prevention member 16B, and stray light prevention member 16B may be fixed to laser unit 12 by screw fastening. This configuration can prevent stray light prevention member 16B from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0066] Also, stray light prevention member 16B may be fixed to the rear surface of glass panel 5. For example, an end of stray light prevention member 16B is fixed to the rear surface of glass panel 5 with an adhesive. This configuration makes it possible to prevent stray light prevention member 16B from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0067] Furthermore, stray light prevention member 16B may be sandwiched between laser unit 12, on which lens barrels 14 and 15 are provided, and the rear surface of glass panel 5. For example, stray light prevention member 16B is sandwiched and fixed between laser unit 12 and glass panel 5 only by the reaction force in the contracted state. Even with this configuration, it is possible to prevent stray light prevention member 16B from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0068] (Adjusting the angle of the telescope tube) By rotating the laser unit 12 around the axis 13, the angles of the lens barrels 14 and 15 can be adjusted up and down. 10B shows a case where the angles of the lens barrels 14 and 15 are adjusted downward. As shown in FIG. 10B, the angles of the lens barrels 14 and 15 can be adjusted downward by rotating the laser unit 12 around the axis 13 in the direction of the arrow B. At this time, the upper portion of the stray light prevention member 16B in FIG. 10B is contracted as shown by the arrow, and the lower portion is extended as shown by the arrow. Even in these states, the end face of the stray light prevention member 16B is pressed against the rear surface of the glass panel 5 due to the elastic force caused by the overall expansion and contraction of the stray light prevention member 16B.

[0069] 10C shows a case where the angles of the lens barrels 14 and 15 are adjusted upward. As shown in FIG. 10C, the angles of the lens barrels 14 and 15 can be adjusted upward by rotating the laser unit 12 around the axis 13 in the direction of the arrow C. At this time, the upper portion of the stray light prevention member 16B in FIG. 10C is extended as shown by the arrows, and the lower portion is contracted as shown by the arrows. Even in these states, the end face of the stray light prevention member 16B is pressed against the rear surface of the glass panel 5 due to the elastic force caused by the overall expansion and contraction of the stray light prevention member 16B.

[0070] (Opening diameter setting) Furthermore, stray light prevention member 16B may adjust the angles of barrels 14, 15 within a preset adjustment range, or may have through-holes with an opening diameter that prevents barrels 14, 15 from interfering with the inner walls of the through-holes. This configuration prevents stray light prevention member 16B from restricting the angle adjustment of barrels 14, 15. Since the angle by which laser unit 12 can be rotated around axis 13 is predetermined, the vertical angle of lens barrels 14, 15 can be adjusted within an adjustment range corresponding to this rotation angle. In addition, by moving laser unit 12 in the horizontal direction, the angle of lens barrels 14, 15 can be adjusted left and right. For example, since the angle by which laser unit 12 can be moved horizontally is predetermined, lens barrels 14, 15 can be adjusted left and right within an adjustment range corresponding to this angle. For example, the opening diameter of the through-hole portion may be determined according to the above formula (1) and formula (2).

[0071] (Blinding effect of stray light prevention material) Glass panel 5 is formed opaque at least in an area on the back surface thereof except for an area including a portion that contacts the end face of stray light prevention member 16A or 16B. For example, glass panel 5 is coated with an opaque material such as black, except for an area facing camera 11 on the back surface thereof and an area including a portion that contacts the end face of stray light prevention member 16A or 16B on the back surface thereof. This makes it possible to prevent the interior of measurement housing 3 from being seen through glass panel 5.

[0072] As described above, in the stray light prevention structure A according to embodiment 2, stray light prevention member 16A is a bellows-shaped tube. This prevents the laser light emitted from lens barrel 14 from propagating to the rear surface of glass panel 5, and therefore stray light prevention structure A can prevent the generation of stray light caused by the laser light emitted from lens barrel 14.

[0073] In the stray light prevention structure A according to the second embodiment, the stray light prevention member 16B is an elastic sponge member, which prevents the laser light emitted from the lens barrel 14 from propagating to the rear surface of the glass panel 5. Therefore, the stray light prevention structure A can prevent the generation of stray light caused by the laser light emitted from the lens barrel 14.

[0074] In the stray light prevention structure A according to the second embodiment, the glass panel 5 is formed opaque except for at least a region on the back side that includes a portion that contacts the end face of the stray light prevention member 16A or 16B. This makes it possible to prevent the interior of the measurement housing 3 from being seen through the glass panel 5.

[0075] In stray light prevention structure A according to embodiment 2, stray light prevention member 16A or 16B has a through-hole with an opening diameter that prevents barrels 14, 15 from interfering with the inner wall even when the angles of barrels 14, 15 are adjusted within a preset adjustment range. This prevents stray light prevention member 16A or 16B from restricting the angle adjustment of barrels 14, 15.

[0076] In stray light prevention structure A according to embodiment 2, stray light prevention member 16A or 16B is fixed to laser unit 12 provided with lens barrels 14 and 15. This makes it possible to prevent displacement of stray light prevention member 16A or 16B when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0077] In stray light prevention structure A according to embodiment 2, stray light prevention member 16A or 16B is fixed to the rear surface of glass panel 5. This makes it possible to prevent misalignment of stray light prevention member 16A or 16B when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0078] In stray light prevention structure A according to embodiment 2, stray light prevention member 16A or 16B is sandwiched between laser unit 12, which is provided with lens barrels 14 and 15, and the rear surface of glass panel 5. This makes it possible to prevent misalignment of stray light prevention member 16A or 16B when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0079] The laser distance measuring device 1 according to the second embodiment includes a measurement housing 3, lens barrels 14 and 15, a glass panel 5 arranged between the measurement housing 3 and the outside, and a stray light prevention structure A having a stray light prevention member 16A or 16B. The stray light prevention structure A makes it possible to provide a laser distance measuring device 1 in which the generation of stray light caused by the laser light emitted from the lens barrel 14 is prevented.

[0080] Embodiment 3 In the first embodiment, the bellows portion that generates the elastic force is a part of the stray light prevention member, but in the third embodiment, a case will be described in which the elastic portion mechanically generates the elastic force.

[0081] 11A is a side view showing laser unit 12 to which stray light prevention member 16C according to embodiment 3 is attached. Laser unit 12 to which stray light prevention member 16C is attached is provided in measurement housing 3 included in laser distance measuring device 1 according to embodiment 3. Stray light prevention member 16C is a member made up of cylindrical portion 163 having a through-hole and coil spring 164. Cylindrical portion 163 is a tubular portion to which coil spring 164 is attached at one end, and is made of a material that does not transmit laser light irradiated from lens barrel 14. The coil spring 164 may be any coil spring that generates elastic force, and the lens barrel is inserted along the center of the coil.

[0082] The height of stray light prevention member 16C may be higher than barrels 14, 15, greater than the distance from the base of barrels 14, 15 in laser unit 12 to the rear surface of glass panel 5, and may be such that the ends of barrels 14, 15 can be inserted into the through-holes of cylindrical portion 163. When stray light prevention member 16C is attached to the inside of measurement housing 3 by inserting barrels 14, 15 into coil spring 164 and the through-holes of cylindrical portion 163, coil spring 164 becomes compressed. A reaction force is generated as coil spring 164 in its compressed state tries to return to its original state, and this reaction force becomes an elastic force that presses the end face of cylindrical portion 163 against and contacts the rear surface of glass panel 5. At this time, lens barrels 14 and 15 are covered by glass panel 5 and cylindrical portion 163, so that the laser light emitted from lens barrel 14 is prevented from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0083] Although the case where stray light prevention member 16C is attached to lens barrel 14 and lens barrel 15 is shown, stray light prevention structure A is not limited to this. For example, stray light prevention member 16C only needs to be attached to either lens barrel 14 or lens barrel 15, and so may be attached only to lens barrel 14 or only to lens barrel 15. Even with this structure, lens barrel 14 or lens barrel 15 is covered by glass panel 5 and cylindrical portion 163 of stray light prevention member 16C, so that the laser light emitted from lens barrel 14 is prevented from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0084] Also, stray light prevention member 16C may be fixed to laser unit 12 provided with lens barrels 14 and 15. For example, a screw fastening piece is provided on coil spring 164, and stray light prevention member 16C is fixed to laser unit 12 by screw fastening. With this configuration, it is possible to prevent stray light prevention member 16C from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0085] Also, stray light prevention member 16C may be fixed to the rear surface of glass panel 5. For example, an end face of cylindrical portion 163 of stray light prevention member 16C is fixed to the rear surface of glass panel 5 with an adhesive. This configuration makes it possible to prevent stray light prevention member 16C from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0086] Furthermore, stray light prevention member 16C may be sandwiched between laser unit 12, which is provided with lens barrels 14 and 15, and the rear surface of glass panel 5. For example, stray light prevention member 16C is sandwiched and fixed between laser unit 12 and glass panel 5 only by the reaction force of coil spring 164 in a compressed state. Even with this configuration, it is possible to prevent stray light prevention member 16C from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0087] (Adjusting the angle of the telescope tube) By rotating the laser unit 12 around the axis 13, the angles of the lens barrels 14 and 15 can be adjusted up and down. 11B shows a case where the angles of the lens barrels 14 and 15 are adjusted downward. As shown in FIG. 11B, the angles of the lens barrels 14 and 15 can be adjusted downward by rotating the laser unit 12 around the axis 13 in the direction of arrow B. At this time, the coil spring 164 of the stray light prevention member 16C attached to the upper lens barrel 14 in FIG. 11B is compressed as shown by the arrow, and the coil spring 164 of the stray light prevention member 16C attached to the lower lens barrel 15 is extended as shown by the arrow. Even in these states, the end faces of each stray light prevention member 16C are pressed against the rear surface of the glass panel 5 due to the elastic force caused by the overall expansion and contraction of the stray light prevention member 16C.

[0088] 11C shows a case where the angles of the lens barrels 14 and 15 are adjusted upward. As shown in FIG. 11C, the angles of the lens barrels 14 and 15 can be adjusted upward by rotating the laser unit 12 around the axis 13 in the direction of the arrow C. At this time, the coil spring 164 of the stray light prevention member 16C attached to the upper lens barrel 14 in FIG. 11C is extended as shown by the arrow, and the coil spring 164 of the stray light prevention member 16C attached to the lower lens barrel 15 is contracted as shown by the arrow. Even in these states, the end faces of the stray light prevention members 16C are pressed against the rear surface of the glass panel 5 due to the elastic force of the coil springs 164 caused by the expansion and contraction of the coil springs 164.

[0089] (Opening diameter setting) Furthermore, cylindrical portion 163 of stray light prevention member 16C may have a through-hole with an opening diameter that allows adjustment of the angles of barrels 14, 15 within a preset adjustment range, and does not cause barrels 14, 15 to interfere with the inner wall of the through-hole. This configuration prevents stray light prevention member 16C from restricting the angle adjustment of barrels 14, 15. Since the angle by which laser unit 12 can be rotated around axis 13 is predetermined, the vertical angle of lens barrels 14, 15 can be adjusted within an adjustment range corresponding to this rotation angle. In addition, by moving laser unit 12 in the horizontal direction, the angle of lens barrels 14, 15 can be adjusted left and right. For example, since the angle by which laser unit 12 can be moved horizontally is predetermined, lens barrels 14, 15 can be adjusted left and right within an adjustment range corresponding to this angle. For example, the opening diameter of the through-hole portion may be determined according to the above formula (1) and formula (2).

[0090] (Variation) The stray light prevention member may have an X-link mechanism as the elastic portion. 12A is a side view showing laser unit 12 to which stray light prevention member 16D, which is a modified example of the stray light prevention member according to the third embodiment, is attached. Laser unit 12 to which stray light prevention member 16D is attached is provided in measurement housing 3 included in laser distance measuring device 1 according to the third embodiment. As shown in FIG. 12A, stray light prevention member 16D is configured to include cylindrical portion 165 having a through-hole and X-link mechanism 166 that generates elastic force. Cylindrical portion 165 shown in FIG. 12A is a square tube and is made of a material that does not transmit the laser light irradiated from lens barrel 14. Stray light prevention member 16D is attached by inserting lens barrels 14, 15 into the through-hole of cylindrical portion 165 via X-link mechanism 166.

[0091] The height of stray light prevention member 16D should be higher than barrels 14, 15, larger than the distance from the base of barrels 14, 15 in laser unit 12 to the rear surface of glass panel 5, and should be such that the ends of barrels 14, 15 can be inserted into the through-holes of cylindrical portion 165. When stray light prevention member 16D is attached to the inside of measurement housing 3 by inserting barrels 14, 15 into X link mechanism 166 and the through-holes of cylindrical portion 165, X link mechanism 166 is in a contracted state. A reaction force is generated when tension spring 19 of X-link mechanism 166, which is in a compressed state, tries to return to its original state, and this reaction force becomes an elastic force that presses the end face of cylindrical portion 165 against and into contact with the rear surface of glass panel 5. At this time, lens barrels 14, 15 are covered by glass panel 5 and cylindrical portion 165, so that the laser light emitted from lens barrel 14 is prevented from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0092] Although the case where stray light prevention member 16D is attached to lens barrel 14 and lens barrel 15 is shown, stray light prevention structure A is not limited to this. For example, stray light prevention member 16D only needs to be attached to either lens barrel 14 or lens barrel 15, and so may be attached only to lens barrel 14 or only to lens barrel 15. Even with this structure, lens barrel 14 or lens barrel 15 is covered by glass panel 5 and cylindrical portion 165 of stray light prevention member 16D, so that the laser light emitted from lens barrel 14 is prevented from being reflected on the surface of glass panel 5 and propagating to lens barrel 15.

[0093] Fig. 12B is an exploded perspective view showing the configuration of X link mechanism 166. As shown in Fig. 12B, X link mechanism 166 includes a fixed part 20, a plate-shaped member 21, and a screw 22 in addition to tension spring 19 shown in Fig. 12A. The plate-like members 21 include a first plate-like member having an elongated hole 21a formed at one end and holes 21b formed at the other end and in the center, and a second plate-like member having holes 21b formed at both ends and in the center. In the X-link mechanism 166, the first plate-like member and the second plate-like member are assembled in an X shape so as to be rotatable around hole 21b in the center.

[0094] The first plate-like members are assembled so that the long hole portions 21a are on the cylindrical portion 165 side. A pair of plate-like members assembled in an X shape is provided on each side. The elongated hole 21a of the first plate-shaped member is attached to the side surface of the cylindrical portion 165 by a screw 22. The second plate-shaped member is attached to the side surface of the cylindrical portion 165 by a screw 22 through a hole 21b at the end. As a result, when the X link mechanism 166 expands or contracts, the first plate-shaped member moves such that the screw 22 slides along the elongated hole 21a, and the second plate-shaped member rotates around the hole 21b.

[0095] A rod connecting the pair of plate-like members on both sides is attached to hole 21b at the end of the first plate-like member. Fixing component 20 supports the rod and is fixed to laser unit 12 with screws 22, as shown in FIG. 12B. In this way, stray light prevention member 16D is fixed to laser unit 12, which is provided with lens barrels 14 and 15. This configuration makes it possible to prevent misalignment of stray light prevention member 16D when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0096] 12A, tension springs 19 are attached to holes 21b at the ends of the first plate-like member and holes 21b at the ends of the second plate-like member. When X link mechanism 166 is in a contracted state (tensioned state), tension spring 19 is extended, and a reaction force is generated in tension spring 19 to return to its original state. When X link mechanism 166 is in an extended state, tension spring 19 is contracted, and a reaction force is generated in tension spring 19 to return to its original state. In this way, X link mechanism 166 can generate an elastic force that presses the end face of tubular portion 165 against the rear surface of glass panel 5.

[0097] Furthermore, fastening of fixing part 20 with screws 22 may be omitted, and stray light prevention member 16D may be fixed to the rear surface of glass panel 5. For example, an end face of cylindrical portion 165 of stray light prevention member 16D may be fixed to the rear surface of glass panel 5 with an adhesive. This configuration makes it possible to prevent stray light prevention member 16D from shifting when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0098] Furthermore, the fastening of fixing parts 20 with screws 22 may be omitted, and stray light prevention member 16D may be fixed in a state where it is sandwiched between laser unit 12, on which lens barrels 14 and 15 are provided, and the rear surface of glass panel 5. In this case, stray light prevention member 16D is sandwiched and fixed between laser unit 12 and glass panel 5 only by the reaction force of X link mechanism 166 in a contracted state. Even with this configuration, it is possible to prevent displacement of stray light prevention member 16D when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0099] (Adjusting the angle of the telescope tube) By rotating the laser unit 12 around the axis 13, the angles of the lens barrels 14 and 15 can be adjusted up and down. 12C shows the case where the angles of the lens barrels 14 and 15 are adjusted downward. As shown in FIG. 12C, the angles of the lens barrels 14 and 15 can be adjusted downward by rotating the laser unit 12 around the axis 13 in the direction of arrow B. At this time, the X link mechanism 166 of the stray light prevention member 16D attached to the upper lens barrel 14 in FIG. 12C is contracted as shown by the arrow, and the X link mechanism 166 of the stray light prevention member 16D attached to the lower lens barrel 15 is extended as shown by the arrow. Even in these states, the end faces of each stray light prevention member 16D are pressed against the rear surface of the glass panel 5 due to the elastic force generated by the expansion and contraction of the X link mechanism 166.

[0100] 12D shows the case where the angles of the lens barrels 14 and 15 are adjusted upward. As shown in FIG. 12D, the angles of the lens barrels 14 and 15 can be adjusted upward by rotating the laser unit 12 around the axis 13 in the direction of arrow C. At this time, the X link mechanism 166 of the stray light prevention member 16D attached to the upper lens barrel 14 in FIG. 12D is extended as shown by the arrow, and the X link mechanism 166 of the stray light prevention member 16D attached to the lower lens barrel 15 is contracted as shown by the arrow. Even in these states, the elastic force of the X link mechanism 166 due to the expansion and contraction of the X link mechanism 166 presses the end face of each stray light prevention member 16D against the rear surface of the glass panel 5.

[0101] (Opening diameter setting) Furthermore, the cylindrical portion 165 of the stray light prevention member 16D may have an opening diameter that allows the angle of the lens barrels 14, 15 to be adjusted within a predetermined adjustment range without interfering with the inner wall of the lens barrels 14, 15. This configuration prevents the stray light prevention member 16D from restricting the angle adjustment of the lens barrels 14, 15. Because the angle at which the laser unit 12 can rotate around the axis 13 is predetermined, the vertical angle of the lens barrels 14, 15 can be adjusted within an adjustment range corresponding to this rotation angle. Furthermore, the angle of the lens barrels 14, 15 can be adjusted left and right by moving the laser unit 12 horizontally. For example, because the angle at which the laser unit 12 can be moved horizontally is predetermined, the lens barrels 14, 15 can be adjusted left and right within an adjustment range corresponding to this angle. For example, the opening diameter of the through-hole portion of the cylindrical portion 165 may be determined according to the above formulas (1) and (2).

[0102] (Blinding effect of stray light prevention material) Glass panel 5 is formed opaque at least in an area including a portion on the back surface that contacts the end face of stray light prevention member 16C or 16D. For example, glass panel 5 is coated with an opaque material such as black, except for an area facing camera 11 on the back surface and an area including a portion on the back surface that contacts the end face of stray light prevention member 16C or 16D. This makes it possible to prevent the interior of measurement housing 3 from being seen through glass panel 5.

[0103] As described above, in stray light prevention structure A according to embodiment 3, stray light prevention member 16C is made up of coil spring 164 and cylindrical portion 163 having coil spring 164 attached to one end thereof. This prevents the laser light emitted from lens barrel 14 from propagating to the back side of glass panel 5, so stray light prevention structure A can prevent the generation of stray light caused by the laser light emitted from lens barrel 14.

[0104] In stray light prevention structure A according to embodiment 3, stray light prevention member 16D is made up of X link mechanism 166 that expands and contracts along the insertion direction of lens barrels 14 and 15, and tubular portion 165 to which X link mechanism 166 is attached at one end. This prevents the laser light emitted from lens barrel 14 from propagating to the back side of glass panel 5, so stray light prevention structure A can prevent the generation of stray light caused by the laser light emitted from lens barrel 14.

[0105] In the stray light prevention structure A according to the third embodiment, the glass panel 5 is formed opaque except for at least a region on the back side that includes a portion that contacts the end face of the stray light prevention member 16C or 16D. This makes it possible to prevent the interior of the measurement housing 3 from being seen through the glass panel 5.

[0106] In the stray light prevention structure A of embodiment 3, the stray light prevention member 16C or 16D has a through hole portion with an opening diameter that prevents the lens barrels 14, 15 from interfering with the inner wall of the cylindrical portion 163 or the tubular portion 165 even when the angle of the lens barrels 14, 15 is adjusted within a preset adjustment range. This prevents the angle adjustment of the lens barrels 14 and 15 from being restricted by the stray light prevention member 16C or 16D.

[0107] In the stray light prevention structure A according to the third embodiment, the stray light prevention member 16C or 16D is fixed to the laser unit 12 provided with the lens barrels 14 and 15. This makes it possible to prevent the stray light prevention member 16C or 16D from shifting when the laser unit 12 is moved to adjust the angle of the lens barrel 14 or 15.

[0108] In the stray light prevention structure A according to the third embodiment, the stray light prevention member 16C or 16D is fixed to the rear surface of the glass panel 5. This makes it possible to prevent the stray light prevention member 16C or 16D from shifting when the angle of the lens barrel 14 or lens barrel 15 is adjusted by moving the laser unit 12.

[0109] In stray light prevention structure A according to embodiment 3, stray light prevention member 16C or 16D is sandwiched between laser unit 12, which is provided with lens barrels 14 and 15, and the rear surface of glass panel 5. This makes it possible to prevent misalignment of stray light prevention member 16C or 16D when laser unit 12 is moved to adjust the angle of lens barrel 14 or lens barrel 15.

[0110] The laser distance measuring device 1 according to the third embodiment includes a measurement housing 3, lens barrels 14 and 15, a glass panel 5 arranged between the measurement housing 3 and the outside, and a stray light prevention structure A having a stray light prevention member 16C or 16D. The stray light prevention structure A makes it possible to provide a laser distance measuring device 1 in which the generation of stray light caused by the laser light emitted from the lens barrel 14 is prevented.

[0111] Various aspects of the present disclosure are summarized below as appendices.

[0112] (Appendix 1) A stray light prevention structure for a laser distance measuring device, comprising: a housing; a lens barrel for transmitting or receiving laser light provided within the housing; and a panel member disposed between the housing and the outside, a stray light prevention member having a through-hole into which the lens barrel is inserted and generating an elastic force; The end surface of the stray light prevention member where the through hole portion is open is pressed against and in contact with the rear surface of the panel member. A stray light prevention structure characterized by: (Appendix 2) The stray light prevention member is provided on at least one of the lens barrels for transmitting and receiving laser light. 2. The stray light prevention structure according to claim 1, (Appendix 3) The stray light prevention member is a cylindrical member having a bellows portion that generates elastic force and a cylindrical portion having the bellows portion formed at one end thereof. 3. The stray light prevention structure according to claim 1 or 2, (Appendix 4) The stray light prevention member is a bellows-shaped tube. 3. The stray light prevention structure according to claim 1 or 2, (Appendix 5) The stray light prevention member is an elastic sponge member. 3. The stray light prevention structure according to claim 1 or 2, (Appendix 6) The stray light prevention member comprises a coil spring and a cylindrical portion to which the coil spring is attached at one end. 3. The stray light prevention structure according to claim 1 or 2, (Appendix 7) The stray light prevention member is composed of an X-link mechanism that expands and contracts along the insertion direction of the lens barrel, and a cylindrical part to which the X-link mechanism is attached at one end. 3. The stray light prevention structure according to claim 1 or 2, (Appendix 8) The panel member is formed opaque at least in a region on the back surface side other than a region including a portion where the end face of the stray light prevention member comes into contact. 8. The stray light prevention structure according to any one of claims 1 to 7. (Appendix 9) The stray light prevention member has the through-hole portion with an opening diameter that prevents the lens barrel from interfering with the inner wall even when the angle of the lens barrel is adjusted within a preset adjustment range. 9. The stray light prevention structure according to any one of claims 1 to 8, (Appendix 10) The stray light prevention member is fixed to the laser unit in which the lens barrel is provided. 10. The stray light prevention structure according to any one of claims 1 to 9, (Appendix 11) The stray light prevention member is fixed to the rear surface of the panel member. 10. The stray light prevention structure according to any one of claims 1 to 9, (Appendix 12) The stray light prevention member is sandwiched between the laser unit provided with the lens barrel and the rear surface of the panel member. 10. The stray light prevention structure according to any one of claims 1 to 9, (Appendix 13) The housing; At least one of the lens barrels for transmitting and receiving laser light; The panel member is disposed between the housing and the outside; A stray light prevention structure according to any one of Supplementary Note 1 to Supplementary Note 12; A laser distance measuring device comprising:

[0113] It is possible to combine the embodiments, modify any of the components of the embodiments, or omit any of the components of the embodiments. [Explanation of symbols]

[0114] 1 laser distance measuring device, 2 main body, 3 measurement housing, 4 base, 5 glass panel, 5A opaque coating layer, 5B transparent area, 11 camera, 12 laser unit, 13 axis, 14, 15 lens barrel, 16, 16A to 16D stray light prevention member, 19 tension spring, 20 fixing part, 21 plate-shaped member, 21a elongated hole portion, 21b hole portion, 22 screw, 161, 163 cylindrical portion, 162 bellows portion, 164 coil spring, 165 cylindrical portion, 166 X-link mechanism, A stray light prevention structure.

Claims

1. A stray light prevention structure for a laser distance measuring device, comprising: a housing; a lens barrel for transmitting or receiving laser light provided within the housing; and a panel member disposed between the housing and the outside, a stray light prevention member having a through-hole into which the lens barrel is inserted and generating an elastic force; The end surface of the stray light prevention member where the through hole portion is open is pressed against and in contact with the rear surface of the panel member. A stray light prevention structure characterized by:

2. The stray light prevention member is provided on at least one of the lens barrels for transmitting and receiving laser light.

2. The stray light prevention structure according to claim 1.

3. The stray light prevention member is a cylindrical member having a bellows portion that generates elastic force and a cylindrical portion having the bellows portion formed at one end thereof.

2. The stray light prevention structure according to claim 1.

4. The stray light prevention member is a bellows-shaped tube.

2. The stray light prevention structure according to claim 1.

5. The stray light prevention member is an elastic sponge member.

2. The stray light prevention structure according to claim 1.

6. The stray light prevention member comprises a coil spring and a cylindrical portion to which the coil spring is attached at one end.

2. The stray light prevention structure according to claim 1.

7. The stray light prevention member comprises an X-link mechanism that expands and contracts along the insertion direction of the lens barrel, and a cylindrical portion to which the X-link mechanism is attached at one end.

2. The stray light prevention structure according to claim 1.

8. The panel member is formed opaque at least in a region on the back surface side other than a region including a portion where the end face of the stray light prevention member comes into contact.

2. The stray light prevention structure according to claim 1.

9. The stray light prevention member has the through-hole portion with an opening diameter that prevents the lens barrel from interfering with the inner wall even when the angle of the lens barrel is adjusted within a preset adjustment range.

2. The stray light prevention structure according to claim 1.

10. The stray light prevention member is fixed to the laser unit in which the lens barrel is provided.

2. The stray light prevention structure according to claim 1.

11. The stray light prevention member is fixed to the rear surface of the panel member.

2. The stray light prevention structure according to claim 1.

12. The stray light prevention member is sandwiched between the laser unit provided with the lens barrel and the rear surface of the panel member.

2. The stray light prevention structure according to claim 1.

13. The housing; At least one of the lens barrels for transmitting and receiving laser light; The panel member is disposed between the housing and the outside; The stray light prevention structure according to any one of claims 1 to 12; A laser distance measuring device comprising:

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