Optical displacement meter

Abstract

The utility model provides an optical displacement meter. The present invention suppresses the influence of rotational driving on a connection portion that connects a rotational driving portion and a fixed portion. The optical displacement meter includes: a light projecting / receiving module including a light projecting portion that irradiates a workpiece with slit light extending in an X direction, a light receiving lens that converges reflected light from the workpiece, and an imaging portion that receives the light converged by the light receiving lens; a motor that integrally rotates the light-projecting / light-receiving module; a housing that accommodates the light projection / reception module; a fixed substrate fixed to the housing; and a first flexible printed circuit board that connects the light projecting / receiving module and the fixed substrate. The first flexible printed circuit board has a curved portion over the entire range of a first angle range of a measurement object of the light projection / reception module.

Description

Technical Field

[0001] The utility model relates to an optical displacement meter. Background Art

[0002] When using a conventional optical displacement meter to obtain the two-dimensional profile of the XZ cross section of the measured object (workpiece) at different positions in the Y direction and generate three-dimensional shape data based on these two-dimensional profiles, the conventional optical displacement meter must be moved relative to the workpiece in the Y direction. Therefore, equipment such as a conveyor belt for transporting the workpiece and a direct-acting mechanism for moving the conventional optical displacement meter body relative to the workpiece is required. However, installation space, cost, etc. may become obstacles to the introduction of the above-mentioned equipment. In addition, when the conventional optical displacement meter is moved by a direct-acting mechanism, the cable connecting the conventional optical displacement meter to the external device sometimes breaks due to bending fatigue.

[0003] On the other hand, as an optical displacement meter that can obtain the two-dimensional contours of the XZ cross-section of the workpiece at different positions in the Y direction and generate three-dimensional shape data based on these two-dimensional contours without the need for the above-mentioned equipment, an optical displacement meter that rotates the light projection system and the light receiving system is known (see Patent Documents 1 and 2).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: European Patent Application Publication No. 3232152

[0007] Patent Document 2: Chinese Utility Model Specification No. 210664364 Utility Model Content

[0008] Problems to be solved by utility models

[0009] An optical displacement meter that rotates a light projecting system and a light receiving system has a structure including a rotation drive unit and a fixed unit. The connection portion connecting the rotation drive unit and the fixed unit may be affected by the rotation drive.

[0010] However, Patent Documents 1 and 2 do not take any countermeasures against the influence of the rotational drive on the connection portion connecting the rotational drive section and the fixing section.

[0011] In view of the above-mentioned problems, an object of the present invention is to provide an optical displacement meter capable of suppressing the influence of rotational drive on a connection portion connecting a rotational drive unit and a fixing unit.

[0012] Solutions for solving problems

[0013] The optical displacement meter involved in the utility model comprises, for example: a light-projecting and light-receiving module, which has a light-projecting portion for irradiating a workpiece with slit light extending along the X direction, a light-receiving lens for converging reflected light from the workpiece, and a camera portion for receiving the light converged by the light-receiving lens; a motor, which rotates the light-projecting and light-receiving module as a whole; a housing, which accommodates the light-projecting and light-receiving module; a fixed substrate, which is fixed to the housing; and a first flexible printed circuit board, which connects the light-projecting and light-receiving module to the fixed substrate, wherein the first flexible printed circuit board has a curved portion within the entire range of a first angle range of a measurement object of the light-projecting and light-receiving module.

[0014] Preferably, there is also a guiding structure, which is used to change the position of the bent portion of the first flexible printed circuit board along with the rotation of the light projecting and receiving module, and to make the change in the curvature radius of the bent portion caused by the rotation of the light projecting and receiving module within the entire range of the first angle range converge within a specified range.

[0015] Preferably, the guide structure has a first guide member fixed to the shell and a second guide member that rotates integrally with the light projecting and light receiving module through the motor, and when observed along the rotation axis direction of the light projecting and light receiving module, the first flexible printed circuit board has the bent portion between the first guide member and the second guide member within the entire range of the first angle range.

[0016] Preferably, the first flexible printed circuit board has a first portion guided along the first guide member and a second portion guided along the second guide member, and when viewed along the rotation axis direction of the light projecting and receiving module, the bent portion forms a substantially U-shape from the first portion to the second portion.

[0017] Preferably, the first guide member has a first wall surface which is arc-shaped when viewed along the rotation axis direction of the light projecting and light receiving module and is used to guide the first part, and the second guide member has a second wall surface which is arc-shaped when viewed along the rotation axis direction of the light projecting and light receiving module and is used to guide the second part, and the first wall surface and the second wall surface are arranged in approximately concentric circles with the rotation axis of the light projecting and light receiving module as the center.

[0018] Preferably, a curvature radius of the second wall surface is smaller than a curvature radius of the first wall surface and larger than the curvature radius of the bent portion of the first flexible printed circuit board.

[0019] Preferably, the first flexible printed circuit board electrically connects the camera unit with the fixed substrate, the light projecting and light receiving module further comprises a second flexible printed circuit board, the second flexible printed circuit board electrically connects the light projecting unit with the fixed substrate, the second flexible printed circuit board comprises a curved portion within the entire range of the first angle range, the guiding structure causes the position of the curved portion of the second flexible printed circuit board to change along with the rotation of the light projecting and light receiving module, and causes the change in the radius of curvature of the curved portion caused by the rotation of the light projecting and light receiving module within the entire range of the first angle range to converge within a specified range.

[0020] Preferably, the first flexible printed circuit board and the second flexible printed circuit board are integrally guided by the guide structure in a state where they are aligned in the direction of the rotation axis of the light projecting and receiving module.

[0021] Preferably, the guide structure further has a rib structure between the first flexible printed circuit board and the second flexible printed circuit board for preventing the first flexible printed circuit board from contacting the second flexible printed circuit board.

[0022] Preferably, the projecting and receiving light module is configured to be rotatable to a second angular range outside the measurement target and outside the first angular range by rotation of the motor, and the first flexible printed circuit board also has the curved portion throughout the second angular range.

[0023] Preferably, the first flexible printed circuit board has a spiral shape and is configured to be capable of at least one of twisting and extending along a rotation axis of the light projecting and receiving module.

[0024] In addition, other features, elements, steps, advantages, and characteristics will become more apparent from the following modes for carrying out the invention and the accompanying drawings related thereto.

[0025] Effect of utility model

[0026] According to the present invention, it is possible to provide an optical displacement meter capable of suppressing the influence of rotational drive on a connection portion connecting a rotational drive unit and a fixing unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a diagram for explaining an optical displacement measuring system.

[0028] Figure 2 It is a diagram illustrating the principle of triangulation.

[0029] Figure 3 It is a diagram for explaining an optical displacement meter including a reflecting member.

[0030] Figure 4 It is a diagram for explaining the method of detecting the peak position.

[0031] Figure 5 This is a functional block diagram of an optical displacement meter.

[0032] Figure 6 This is a diagram for explaining a first example of the arrangement of the motors.

[0033] Figure 7 This is a diagram for explaining a first example of the arrangement of the motor.

[0034] Figure 8 It is a diagram for explaining a second example of the arrangement of the motors.

[0035] Fig. 9 It is a diagram for explaining a second example of the arrangement of the motors.

[0036] Fig.10 1 is a diagram showing a processing flow of a measurement operation of the optical displacement measurement system.

[0037] Fig.11 The figure schematically shows a housing, a fixed substrate, a light projecting and receiving module, and a first flexible printed circuit board.

[0038] Fig.12 is a diagram showing a first flexible printed circuit board.

[0039] Fig.13 is a diagram schematically showing the second guide. DETAILED DESCRIPTION

[0040] <Optical displacement measurement system>

[0041] Figure 1 1 is a diagram showing a schematic configuration example of an optical displacement measuring system. An optical displacement measuring system 100 of this configuration example includes an optical displacement meter 1 , a control device 2 , a display device 3 , and an input device 4 .

[0042] In this configuration example, the X direction corresponds to the width direction of the slit light L1 output from the optical displacement meter 1, the Z direction corresponds to the height direction of the workpiece W, and the Y direction corresponds to the direction of the slit light L1 passing through the light projection unit (in Figure 1 The XZ plane described later is a plane extending along the X direction and the Z direction. In addition, the optical displacement meter 1 scans the slit light L1 by rotating the light-projecting and light-receiving module 20, so the scanning direction of the slit light L1 is a direction orthogonal to the X direction on the YZ plane, including the Y direction. In addition, in this specification, "rotation" means reciprocating swinging motion centered on the rotation axis.

[0043] The optical displacement measurement system 100 is a system for measuring the contour and three-dimensional shape of a workpiece W. The contour of the workpiece W refers to data indicating the outer edge of a cross-section surface of the workpiece W generated by the slit light L1. When the slit light is irradiated parallel to the XZ plane, the contour of the workpiece W becomes data indicating the outer edge of the cross-section surface parallel to the XZ plane, and is therefore also referred to as a two-dimensional contour of the XZ cross section of the workpiece W.

[0044] For example, a contour is a collection of (xi, zi) (i is an index). xi represents the position in the X direction. zi represents the height in the Z direction. In addition, a three-dimensional shape is a collection of (xi, yi, zi). yi represents the position in the Y direction.

[0045] The optical displacement meter 1 operates according to the instruction from the control device 2. The optical displacement meter 1 outputs the slit light L1 extending in the X direction and receives the reflected light L2 from the workpiece W. Moreover, the optical displacement meter 1 calculates the contour of the workpiece W based on the light reception result. The optical displacement meter 1 performs imaging at regular intervals to generate the contours of different workpieces W. In addition, the optical displacement meter 1 generates the three-dimensional shape data of the workpiece W based on the contours of different workpieces W.

[0046] The control device 2 outputs instructions based on user input received by the input device 4 to the optical displacement meter 1, and receives measurement results of the workpiece W from the optical displacement meter 1. The control device 2 also outputs display signals to the display device 3. The control device 2 is, for example, a personal computer or a programmable logic controller.

[0047] The display device 3 displays, for example, the measurement result of the workpiece W, a UI (User Interface) for setting the optical displacement meter 1 , and the like based on a display signal from the control device 2 .

[0048] The input device 4 receives user input to the optical displacement measuring system 100. Figure 1 In FIG. 4 , a keyboard and a mouse are illustrated as the input device 4 . However, the input device 4 is not limited to a keyboard and a mouse. For example, the input device 4 may be a touch panel disposed on the display screen of the display device 3 .

[0049] Figure 2 This is a diagram for explaining the principle of light section (triangulation distance measurement). A light projecting unit 11, a light receiving lens 12, and an imaging unit 13 are accommodated inside the housing 10 of the optical displacement meter 1. The light projecting unit 11 has a light source 14 and a light projecting lens 15. For example, the light source 14 is a laser beam emitter, and the light projecting lens 15 may also be composed of a plurality of lenses including a cylindrical lens.

[0050] Light output from the light source 14 is converted into slit light L1 by passing through the light projection lens 15. The housing 10 is provided with a light projection window 16 having light transmission capability for allowing the slit light L1 to pass through. Similarly, the housing 10 is provided with a light receiving window 17 having light transmission capability for allowing the reflected light L2 to pass through.

[0051] The light receiving lens 12 is a lens for converging the reflected light L2 and forming an image on the light receiving surface of the imaging unit 13. The light receiving lens 12 may be a structure including only one lens or a structure including a plurality of lenses. In addition, the light receiving lens 12 may also be a structure including optical components other than lenses (such as optical filters, etc.). The imaging unit 13 is an image sensor having a plurality of photoelectric conversion elements arranged in a two-dimensional manner. The imaging unit 13 receives the light that has been converged by the light receiving lens.

[0052] like Figure 2 As shown, the optical axis AX2 of the light receiving lens 12 is inclined relative to the light projection axis AX1 of the light projecting unit 11. The light projection axis AX1 of the light projecting unit 11 is consistent with the optical axis of the light source 14. As a result, the reflected light L2 from the height Z1 is imaged at the position V1 in the V direction of the light receiving surface of the imaging unit 13, and the reflected light L2 from the height Z2 is imaged at the position V2 in the V direction of the light receiving surface of the imaging unit 13. In other words, the V direction of the light receiving surface of the imaging unit 13 corresponds to the Z direction of the workpiece W. Although the U direction of the light receiving surface of the imaging unit 13 is not shown in the figure, the U direction corresponds to the X direction of the workpiece W. In other words, the longitudinal direction of the image as the light receiving result output by the imaging unit 13 is the V direction, and the lateral direction is the U direction.

[0053] The light projecting unit 11, the light receiving lens 12, and the imaging unit 13 are rotatable around a rotation axis AX3 along the X direction. The relative positions of the light projecting unit 11, the light receiving lens 12, and the imaging unit 13 are fixed. Figure 2 In the figure, the solid line shows the state of the light projecting unit 11, the light receiving lens 12 and the camera unit 13 before rotating in the counterclockwise direction CCW, and the dotted line shows the state of the light projecting unit 11, the light receiving lens 12 and the camera unit 13 after rotating in the counterclockwise direction CCW.

[0054] The light projecting unit 11, the light receiving lens 12, and the imaging unit 13 can rotate around the rotation axis AX3 along the X direction in a state where the light receiving surface of the imaging unit 13 is tilted relative to the optical axis of the light receiving lens 12 and satisfies Scham's law. Figure 2 In the region R1 indicated by a grid, each cross section through which the optical axis AX1 passes is in focus. That is, even if the height of the workpiece W changes, the optical displacement meter 1 can generate the contour of the workpiece W in focus.

[0055] In addition, the positional relationship between the light projecting unit 11, the light receiving lens 12, and the imaging unit 13 may also be different from Figure 2 The positional relationship shown is reversed.

[0056] In addition, if Figure 3 As shown, the optical displacement meter 1 may also include a reflecting member 18. The reflecting member 18 is disposed on the optical path between the light receiving window 17 and the imaging unit 13, and is used to bend the reflected light L2 and the optical axis AX2 of the light receiving lens 12 back to the light projecting unit 11 side. Thus, a light projecting and light receiving module that integrally holds the light projecting unit 11, the light receiving lens 12, the imaging unit 13, and the reflecting member 18 can be compactly constructed on a YZ plane extending along the Y direction and the Z direction. Therefore, the moment of inertia of the light projecting and light receiving module that integrally holds the light projecting unit 11, the light receiving lens 12, the imaging unit 13, and the reflecting member 18 around the rotation axis AX3 can be reduced.

[0057] exist Figure 3 In the embodiment, the reflective member 18 is disposed on the optical path between the light receiving lens 12 and the imaging unit 13, but the reflective member 18 may also be disposed on the optical path between the light receiving window 17 and the light receiving lens 12 (for example, see the following description). Figure 8 and Fig. 9 ).

[0058] When the reflective member 18 is disposed on the optical path between the light receiving lens 12 and the imaging unit 13, the reflective member 18 reflects the light focused by the light receiving lens 12, so that the area of ​​the reflective surface of the reflective member 18 can be reduced. When the reflective member 18 is disposed on the optical path between the light receiving window 17 and the light receiving lens 12, the heavy light receiving lens 12 can be arranged close to the rotation axis AX3, thereby increasing the effect of reducing the moment of inertia.

[0059] <Position (calculation of height)>

[0060] Figure 4 This is a diagram for explaining a method of calculating the height of the contour based on the image I1 as the light receiving result output by the imaging unit 13. The slit light L1 has a certain width in the Y direction. Therefore, the width of the spot generated by the reflected light L2 on the light receiving surface of the imaging unit 13 is also as wide as that across a plurality of photoelectric conversion elements.

[0061] Therefore, the optical displacement meter 1 obtains an approximate curve P1 representing the change in brightness value based on the brightness value of each pixel, and calculates the position of the peak in the approximate curve P1 in the V direction. Figure 4In the figure, the leftmost column is the focus column, and the distribution of the brightness value of the focus column is illustrated (approximate curve P1). The approximate curve P1 is obtained by performing curve fitting on multiple sampling values. Sampling values ​​that are less than the detection threshold are not considered. The position where the peak occurs in the V direction represents the height of the workpiece W. The optical displacement meter 1 obtains the approximate curve P1 at each position (each pixel column) in the U direction, and calculates the position (height) of the peak in the V direction based on the approximate curve P1. By performing this operation processing for each position in the U direction, a contour can be obtained. Such an operation processing can also be called sub-pixel processing.

[0062] In addition, for example, by pre-factory calibration, coordinate transformation conditions (for example, a coordinate transformation table) are generated that represent the correspondence between the UV coordinates and the rotation angle θ and the local coordinates (X, Y, Z), such as represented by (U, V, θ) = (X, Y, Z), and the coordinate transformation conditions are stored in a storage unit (not shown) of the optical displacement meter 1. Therefore, the optical displacement meter 1 can transform the contour in the UV coordinate system into the contour in the XYZ coordinate system based on the rotation angle θ through simple calculations.

[0063] <Function Block>

[0064] Figure 5 1 is a functional block diagram of the optical displacement meter 1. The optical displacement meter 1 includes a light projecting and receiving module 20, a motor 21, and a control unit 22.

[0065] The light projecting and receiving module 20 integrally holds the light projecting unit 11, the light receiving lens 12, and the imaging unit 13. In addition, when the optical displacement meter 1 includes the reflecting member 18, the light projecting and receiving module 20 integrally holds the light projecting unit 11, the light receiving lens 12, the imaging unit 13, and the reflecting member 18 (in Figure 5 The light projecting and receiving module 20 is accommodated in the housing 10.

[0066] The motor 21 rotates the light projecting unit 11, the light receiving lens 12, and the camera unit 13. More specifically, the motor 21 rotates the light projecting and light receiving module 20. The motor 21 can rotate the light projecting and light receiving module 20 by a direct drive method without configuring an intermediate mechanism such as a speed reducer between the motor 21 and the light projecting and light receiving module 20, or can rotate the light projecting and light receiving module 20 via an intermediate mechanism such as a speed reducer.

[0067] The control unit 22 includes a motor control unit 23, a signal processing unit 24, and a communication unit 25. The control unit 22 controls the motor 21 to rotate the light projecting unit 11, the light receiving lens 12, and the imaging unit 13 in a state satisfying the relationship of Scham's law, so that the slit light L1 is scanned in a direction orthogonal to the X direction. More specifically, the motor control unit 23 controls the motor 21 to rotate the light projecting unit 11, the light receiving lens 12, and the imaging unit 13 in a state satisfying the relationship of Scham's law, and the signal processing unit 24 controls the light projecting unit 11 to irradiate the slit light L1 from the light projecting unit 11.

[0068] The signal processing unit 24 includes a peak detection unit 26, a contour generation unit 27, and a three-dimensional data generation unit 28. The peak detection unit 26 detects the position (peak position) of the peak generating the brightness value in the V direction based on the light receiving result output from the camera unit 13. The contour generation unit 27 generates a contour data by summarizing the heights (zi) at each position (xi) in the X direction of the workpiece W obtained by the peak detection unit 26. The three-dimensional data generation unit 28 generates three-dimensional shape data of the workpiece W based on the contours of the workpiece W with different yi generated by the contour generation unit 27. In addition, at least a part of the peak detection unit 26, the contour generation unit 27, and the three-dimensional data generation unit 28 may be set not in the optical displacement meter 1, but in the control device 2 (refer to Figure 1 )’s interior.

[0069] The communication unit 25 performs wired or wireless communication with the control device 2. For example, the communication unit 25 receives instructions from the control device 2 and transmits the instructions to the control unit 22. In addition, the communication unit 25 transmits the contour data and three-dimensional shape data of the workpiece W generated by the signal processing unit 24 to the control device 2.

[0070] <Motor Configuration>

[0071] Figure 6 and Figure 7 It is a diagram for explaining a first example of the arrangement of the motor 21 . Figure 6 yes Figure 7 A cross-sectional view of the optical displacement meter 1 taken along line BB′ perpendicular to the X direction. Figure 7 yes Figure 6 A cross-sectional view of the optical displacement meter 1 along the XZ plane at line AA′.

[0072] In the first example, the light projecting and receiving module 20 includes a plate-shaped base member 201 extending along a plane perpendicular to the X direction. The light projecting unit 11 , the light receiving lens 12 , the imaging unit 13 , and the reflecting member 18 are mounted on the base member 201 .

[0073] In the first example, the light-projecting and light-receiving module 20 does not overlap with the motor 21 and the accessory parts of the motor 21 in the X direction. The accessory parts of the motor 21 are, for example, encoders that detect the amount of rotation of the rotor of the motor 21. According to the first example of the configuration of the motor 21, it is easy to configure the light-projecting unit 11, the light-receiving lens 12, and the camera unit 13 close to each other. By making the light-projecting unit 11, the light-receiving lens 12, and the camera unit 13 close to each other, the light-projecting and light-receiving module 20 can be compactly configured. Therefore, the moment of inertia of the light-projecting and light-receiving module 20 around the rotation axis AX3 can be reduced.

[0074] In the first example, the control unit 22 does not overlap with the light projecting and receiving module 20 in the X direction, but overlaps with the motor 21 in the X direction.

[0075] Figure 8 and Fig. 9 It is a diagram for explaining a second example of the arrangement of the motor 21 . Figure 8 yes Fig. 9 A cross-sectional view of the optical displacement meter 1 taken along line BB′ perpendicular to the X direction. Fig. 9 yes Figure 8 A cross-sectional view of the optical displacement meter 1 taken along line AA′ perpendicular to the Z direction.

[0076] In the second example, the light projecting and light receiving module 20 includes a base member 201. The base member 201 includes a cylinder extending in the X direction, a cover for blocking one end of the cylinder in the X direction, and a flange extending radially outward from the other end of the cylinder in the X direction. The light projecting unit 11, the light receiving lens 12, the imaging unit 13, and the reflecting member 18 are mounted on the flange of the base member 201.

[0077] In the second example, the light projecting and light receiving module 20 overlaps with at least one of the motor 21 and the accessory of the motor 21 in the X direction. As in the first example, the accessory of the motor 21 is, for example, an encoder that detects the amount of rotation of the rotor of the motor 21. According to the second example of the arrangement of the motor 21, it is easy to arrange the light projecting unit 11 away from the light receiving lens 12 and the imaging unit 13. By arranging the light projecting unit 11 away from the light receiving lens 12 and the imaging unit 13, the scanning range of the slit light L1 can be expanded.

[0078] In the second example, the control unit 22 overlaps with the light-projecting and light-receiving module 20 and the motor 21 in the X direction. In addition, the control unit 22 may be arranged at a position where it does not overlap with the motor 21 in the X direction and overlaps with the motor 21 when viewed along the X direction. In the case where the control unit 22 is arranged at a position where it does not overlap with the motor 21 in the X direction and overlaps with the motor 21 when viewed along the X direction, the control unit 22 may or may not overlap with the light-projecting and light-receiving module 20 and the motor 21 in the X direction.

[0079] <Processing Flow>

[0080] Fig.10 1 is a diagram showing the processing flow of the measurement operation of the optical displacement measuring system 100. When the input device 4 receives a user input for instructing the start of measurement, the measurement starts. Fig.10 The processing flow.

[0081] First, in step S1, the light projecting unit 11 starts irradiating the slit light L1. In the next step S2, the motor control unit 23 starts rotating the motor 21. In addition, the processing of step S1 and the processing of step S2 can also be performed simultaneously. The motor control unit 23 can also rotate the motor before executing step S1 to move the light projecting and receiving module 20 to a specified scanning start position. Through the processing of step S1 and step S2, the scanning of the slit light L1 starts.

[0082] In the next step S3, the motor control unit 23 determines whether the rotation amount (rotation angle) of the motor 21 from the start of rotation is smaller than a threshold value. If the rotation amount of the motor 21 from the start of rotation is smaller than the threshold value, the determination process of step S3 is continued, and the scanning of the slit light L1 is continued.

[0083] When the rotation amount of the motor 21 from the start of rotation reaches the threshold value, the process proceeds to step S4. In addition, the threshold value is the rotation amount calculated based on the measurement range. The measurement range is set by default. When the measurement range is changed by the user, the control unit 22 (for example, the signal processing unit 24) calculates the threshold value of the rotation amount based on the changed measurement range.

[0084] In step S4, the motor control unit 23 stops the rotation of the motor 21. In the next step S5, the light projecting unit 11 stops the irradiation of the slit light L1. The processing of step S4 and the processing of step S5 may be performed simultaneously. Through the processing of step S4 and step S5, the scanning of the slit light L1 ends.

[0085] In the next step S6, the outline generation unit 27 generates an outline. Alternatively, the outline generation unit 27 may start generating an outline while the slit light L1 is scanning.

[0086] In the next step S7 , the three-dimensional data generating unit 28 generates three-dimensional data.

[0087] In the next step S8, the display device 3 displays the measurement result. The measurement result is, for example, a cross-sectional view of the workpiece W based on the contour, a three-dimensional image of the workpiece W based on the three-dimensional data, etc. When the processing of step S8 is completed, Fig.10 The processing flow ends.

[0088] The optical displacement meter 1 has a measurement period and a non-measurement period, wherein during the measurement period, the light-emitting and light-receiving module 20 is rotated at a substantially constant speed in the first rotation direction (counterclockwise CCW) or the second rotation direction (clockwise CW) to perform the measurement operation, and during the non-measurement period, the rotation direction of the light-emitting and light-receiving module 20 is switched without performing the measurement operation. During the measurement period in which the measurement operation is performed, the motor rotates the light-emitting and light-receiving module 20 at a substantially constant speed within the first angle range described later. Regarding the period of switching the rotation direction performed within the second angle range described later, since deceleration and acceleration need to be considered and the calculation of the correlation between the peak position in the V direction and the rotation angle becomes complicated, it is preferably set as a non-measurement period.

[0089] <Connection between the light emitting and receiving module and the fixed base plate>

[0090] Fig.11 1 is a diagram schematically showing the housing 10 , the light projecting and receiving module 20 , the fixed substrate 30 , and the first flexible printed circuit board 31 . The optical displacement meter 1 further includes the fixed substrate 30 and the first flexible printed circuit board 31 .

[0091] The fixed substrate 30 is fixed to the housing 10. The fixed substrate 30 may be fixed to the housing 10 directly or via another member. The fixed substrate 30 may include, for example, the outline generating unit 27. In addition, the fixed substrate 30 may include, for example, the three-dimensional data generating unit 28 in addition to the outline generating unit 27. If the fixed substrate 30 includes the outline generating unit 27 and the three-dimensional data generating unit 28, it is easy to release the heat generated in the outline generating unit 27 and the three-dimensional data generating unit 28.

[0092] In addition, a first variant of the present embodiment may also be configured as follows: a signal processing unit 24 (e.g., a signal processing substrate) is provided in the light-projecting and light-receiving module 20, and the signal processing unit 24 is electrically connected to the fixed substrate 30 by a first flexible printed circuit board 31. Regarding the optical displacement meter of the first variant, the light-projecting and light-receiving module 20 may be configured to include a contour generating unit 27, or may be configured to also include a three-dimensional data generating unit 28. The contour generating unit 27 and the three-dimensional data generating unit 28 in the first variant may be provided on the same signal processing substrate, or may be provided on separate signal processing substrates electrically connected to each other. A second variant of the present embodiment may also be configured to enable an external device (e.g., Figure 1A measurement system in which a control unit of a control device 2) performs the function of a signal processing unit 24. Regarding the measurement system of the second variant, it can be a structure in which the control unit of an external device performs the function of a contour generating unit 27, or it can be a structure in which the function of a three-dimensional data generating unit 28 is also performed. A third variant of the present embodiment can be set as follows: a two-dimensional contour is generated by a light projection and light receiving module 20, and a three-dimensional data is generated based on the two-dimensional contour by a fixed substrate 30 or a control unit of an external device. A fourth variant of the present embodiment can be set as follows: a two-dimensional contour is generated by a fixed substrate 30, and a three-dimensional data is generated based on the two-dimensional contour by a control unit of an external device.

[0093] The fixed substrate 30 may include, for example, the motor control unit 23. In addition, the fixed substrate 30 may include, for example, the communication unit 25. The fixed substrate 30 may be composed of a single substrate or a plurality of substrates.

[0094] The direction of the mounting surface of the fixed substrate 30 on which the electronic components are mounted is not particularly limited, and may be, for example, perpendicular to the X direction or parallel to the X direction.

[0095] The first flexible printed circuit board 31 connects the light-emitting and light-receiving module 20 to the fixed substrate 30. The first flexible printed circuit board 31 has a curved portion and maintains a curved state throughout the entire range of the first angle range of the measurement target of the light-emitting and light-receiving module 20. When the light-emitting and light-receiving module 20 rotates in the clockwise direction CW, the curved portion (the portion that maintains the curved state) 311 of the first flexible printed circuit board 31 moves to the left. Fig.11 On the contrary, when the light projecting and receiving module 20 rotates in the counterclockwise direction CCW, the bent portion 311 of the first flexible printed circuit board 31 moves to the first direction D1. Fig.11 Movement in the second direction D2 is shown.

[0096] The bending state of the first flexible printed circuit board 31 can be along a two-dimensional curve or a three-dimensional curve. Fig.11 The example shown, Fig.12 An example of a case where the bent state of the first flexible printed wiring board 31 is a shape along a three-dimensional curve is drawn. Fig.12 The first flexible printed circuit board 31 shown has a spiral shape and is configured to be capable of at least one of twisting and expansion and contraction along the rotation axis AX3 of the light projecting and light receiving module 20 .

[0097] Here, the first angle range of the measurement target refers to an angle range set so that the image processing progresses to at least the generation of three-dimensional data by the three-dimensional data generating unit 28 .

[0098] The first flexible printed circuit board 31 maintains a bent state throughout the first angle range of the measurement object of the light projecting and receiving module 20, so that the optical displacement meter 1 can improve the durability of the connection part between the light projecting and receiving module 20 and the fixed substrate 30 against the rotation of the light projecting and receiving module 20 during the measurement operation.

[0099] Preferably, the radius of curvature of the curved portion 311 of the first flexible printed circuit board 31 is substantially the same throughout the first angle range. According to such a structure, the stress distribution of the curved portion 311 can be suppressed from changing due to the rotation of the light projecting and light receiving module 20, so that the occurrence of bending fatigue at the curved portion 311 can be suppressed. Here, substantially equal means within ±2 mm, more preferably within ±1 mm, relative to the radius of curvature of the curved portion 311 when the rotation angle of the light projecting and light receiving module 20 is the center of the first angle range.

[0100] The portion of the first flexible printed circuit board 31 that maintains the bent state moves along the outside of the area where the light-projecting and light-receiving module 20 is arranged in the housing 10 throughout the first angle range of the measurement object. It can also be set that the internal space of the housing 10 is divided into a first area where the fixed substrate 30 is arranged and a second area where the light-projecting and light-receiving module 20 is arranged, and the first flexible printed circuit board 31 moves between the first area and the second area. According to such a structure, even if the light-projecting and light-receiving module 20 rotates, it is possible to suppress the first flexible printed circuit board 31 from interfering with the rotation of the light-projecting and light-receiving module 20. In addition, the optical displacement meter 1 can prevent the fixed substrate 30 from contacting the light-projecting and light-receiving module 20.

[0101] The optical displacement meter 1 further includes an imaging substrate 32 for controlling the imaging unit 13. The light projecting and light receiving module 20 also integrally holds the imaging substrate 32. Therefore, the imaging substrate 32 is a part of the light projecting and light receiving module 20. The direction of the mounting surface of the imaging substrate 32 on which the electronic components are mounted is not particularly limited, and may be, for example, perpendicular to the X direction or parallel to the X direction.

[0102] The first flexible printed circuit board 31 electrically connects the imaging substrate 32 and the fixed substrate 30. The imaging substrate 32 and the fixed substrate 30 may be directly connected via the first flexible printed circuit board 31 or may be indirectly connected via the first flexible printed circuit board 31 and another substrate.

[0103] <Guide>

[0104] like Fig.11As shown in FIG. 1 , the optical displacement meter 1 further includes a guide structure for causing the position of the curved portion of the first flexible printed circuit board 31 to change with the rotation of the light-projecting and light-receiving module 20, and for causing the change in the curvature radius of the curved portion caused by the rotation of the light-projecting and light-receiving module 20 within the entire first angle range to converge within a predetermined range. With this structure, the change in the curvature radius can be made to converge within a predetermined range to suppress the generation of excessive stress concentration. The guide structure includes a first guide 33 and a second guide 34.

[0105] The first guide member 33 may be fixed to the housing 10 directly or via other components. Fig.11 In the example shown, the first guide 33 is fixed to the housing 10 via the fixed base plate 30. The first guide 33 extends in the direction of the rotation axis AX3 of the light projecting and receiving module 20.

[0106] The second guide 34 is rotated integrally with the light projecting and light receiving module 20 by the motor 21. The second guide 34 extends in the direction of the rotation axis AX3 of the light projecting and light receiving module 20.

[0107] The first portion 312 of the first flexible printed circuit board 31 is guided along the first guide 33. The second portion 313 of the first flexible printed circuit board 31 is guided along the second guide 34. When viewed along the rotation axis direction, the first flexible printed circuit board 31 has a curved portion between the first guide 33 and the second guide 34 in the entire range of the first angle range of the measurement object of the light projection and light receiving module 20 and maintains the curved state. Thus, by guiding the first flexible printed circuit board 31 from both the fixed side and the driving side, the movement of the curved portion accompanying the rotation is made more stable, and the radius of curvature is also easily converged within a prescribed range. The first wall surface of the first guide 33 contacts the first portion 312 of the first flexible printed circuit board 31. The second wall surface of the second guide 34 contacts the second portion 313 of the first flexible printed circuit board 31. When viewed along the rotation axis direction, the curved portion forms a substantially U-shape from the first portion 312 to the second portion 313. According to such a structure, the contact area between the first wall surface of the first guide 33 and the first portion 312 of the first flexible printed circuit board 31, and the contact area between the second wall surface of the second guide 34 and the second portion 313 of the first flexible printed circuit board 31 increase or decrease only according to the rotation of the light projecting and light receiving module 20. In addition, the contact portion of the first flexible printed circuit board 31 with the guide does not move in the circumferential direction relative to the first wall surface of the first guide 33 and the second wall surface of the second guide 34, so the contact portion of the first flexible printed circuit board 31 with the guide does not wear. In addition, according to such a structure, the curved portion 311 of the first flexible printed circuit board 31 can be easily formed.

[0108] The first guide 33 has a first wall surface that is arc-shaped when viewed along the rotation axis AX3 direction of the light-projecting and light-receiving module 20 and is used to guide the first part 312. The second guide 34 has a second wall surface that is arc-shaped when viewed along the rotation axis AX3 direction of the light-projecting and light-receiving module 20 and is used to guide the second part 313. The first wall surface of the first guide 33 and the second wall surface of the second guide 34 are arranged in a substantially concentric circle with the rotation axis AX3 of the light-projecting and light-receiving module 20 as the center. As a result, the radius of curvature can be made uniform, thereby suppressing stress concentration caused by changes in the radius of curvature. In addition, the radius of curvature is maintained, so fatigue prediction and life evaluation are easy.

[0109] The curvature radius of the second wall surface of the second guide 34 is smaller than the curvature radius of the first wall surface of the first guide 33, and is larger than the curvature radius of the curved portion 311 of the first flexible printed circuit board 31. Thus, by arranging the first guide 33 on the fixed side at a position further outward than the second guide 34 on the light projecting and receiving module side with respect to the rotation axis AX3, and by setting the curvature radius of the curved portion to be relatively small, efficient arrangement can be achieved.

[0110] <Second Flexible Printed Circuit Board>

[0111] like Fig.11 As shown, the optical displacement meter 1 further includes a second flexible printed circuit board 36 and a light-projecting substrate 35 for controlling the light-projecting unit 11. The light-projecting and light-receiving module 20 also integrally holds the light-projecting substrate 35. Therefore, the light-projecting substrate 35 is a part of the light-projecting and light-receiving module 20. The direction of the mounting surface of the light-projecting substrate 35 on which the electronic components are mounted is not particularly limited, and may be, for example, perpendicular to the X direction or parallel to the X direction.

[0112] The second flexible printed circuit board 36 electrically connects the light projecting substrate 35 and the fixed substrate 30 .

[0113] The guidance of the second flexible printed circuit board 36 by the first guide member 33 and the second guide member 34 is the same as the guidance of the first flexible printed circuit board 31 by the first guide member 33 and the second guide member 34. That is, the guiding structure (for example, the first guide member 33 and the second guide member 34) provided in the optical displacement meter 1 guides multiple flexible printed circuit boards (for example, the first flexible printed circuit board 31 and the second flexible printed circuit board 36) by changing the position of the curved portion of the second flexible printed circuit board 36 along with the rotation of the light-projecting and light-receiving module 20, and making the change in the radius of curvature of the curved portion caused by the rotation of the light-projecting and light-receiving module 20 within the entire range of the first angle range converge within a prescribed range. As a result, the light-projecting system and the light-receiving system rotate as a whole, and each flexible printed circuit board also moves in the same manner, so that space can be saved by setting it as a common guiding structure. In addition, the relationship between the guide and the flexible printed circuit board is not limited to Fig.11 Therefore, for example, the guide provided in the optical displacement meter 1 may guide a single flexible printed circuit board. In other words, the optical displacement meter 1 may be configured to include a guide structure for each of a plurality of flexible printed circuit boards.

[0114] Fig.13 31 is a diagram schematically showing the second guide member 34. The optical displacement meter 1 further includes a rib structure (protrusion) 331 between the first flexible printed circuit board 31 and the second flexible printed circuit board 36 for preventing the first flexible printed circuit board 31 from contacting the second flexible printed circuit board 36. Thus, a short circuit or damage caused by contact between the first flexible printed circuit board 31 and the second flexible printed circuit board 36 can be suppressed. In more detail, as Fig.13 As shown, the second guide 34 has a rib structure 331. In addition, the first guide 33 also has a rib structure 331 similarly to the second guide 34.

[0115] The optical displacement meter 1 further includes a rib structure (protrusion) 332 for restricting the first flexible printed circuit board 31 from moving away from the second flexible printed circuit board 36. The rib structure (protrusion) 331 and the rib structure (protrusion) 332 restrict the movement of the first flexible printed circuit board 31 in the X direction.

[0116] The optical displacement meter 1 further includes a rib structure (protrusion) 333 for restricting the second flexible printed circuit board 36 from moving away from the first flexible printed circuit board 31. The rib structure (protrusion) 331 and the rib structure (protrusion) 333 restrict the movement of the second flexible printed circuit board 36 in the X direction.

[0117] <Angle range of light emitting and receiving modules>

[0118] The light projecting and receiving module 20 may be configured to be rotatable to a second angle range outside the first angle range and outside the measurement target by the rotation of the motor 21. Preferably, the first flexible printed circuit board 31 maintains the curved state throughout the second angle range.

[0119] Here, the second angle range outside the measurement object refers to an angle range set so that the image processing does not proceed to the generation of three-dimensional data by the three-dimensional data generating unit 28. Therefore, within the second angle range outside the measurement object, the image processing may proceed to the generation of the contour by the contour generating unit 27, or the image processing may not proceed to the generation of the contour by the contour generating unit 27.

[0120] Since the first flexible printed circuit board 31 maintains the bent state throughout the second angle range, the optical displacement meter 1 can improve the durability of the connection portion between the light projecting and light receiving module 20 and the fixed substrate 30 against, for example, the switching operation of the rotation direction and the rotation of the light projecting and light receiving module 20 during the maintenance operation. In addition, the maintenance operation refers to the operation of rotating the motor 21 in a manner that the rotation angle range of the motor 21 is larger than the rotation angle range during the measurement operation in order to suppress the micro vibration wear of the bearing of the motor 21.

[0121] <Conclusion>

[0122] The various embodiments described above will be generally described below.

[0123] For example, the optical displacement meter disclosed in this specification comprises: a light-projecting and light-receiving module, which has a light-projecting portion that irradiates a workpiece with slit light extending along the X direction, a light-receiving lens that converges reflected light from the workpiece, and a camera portion that receives the light converged by the light-receiving lens; a motor that rotates the light-projecting and light-receiving module as a whole; a housing that accommodates the light-projecting and light-receiving module; a fixed substrate that is fixed to the housing; and a first flexible printed circuit board that connects the light-projecting and light-receiving module to the fixed substrate, wherein the first flexible printed circuit board has a curved portion (a first structure) over the entire range of a first angle range of a measurement object of the light-projecting and light-receiving module.

[0124] In the optical displacement meter of the above-mentioned first structure, it can also be the following structure: it is also equipped with a guiding structure, which is used to make the position of the bent portion of the first flexible printed circuit board change along with the rotation of the light projecting and receiving module, and make the change in the curvature radius of the bent portion caused by the rotation of the light projecting and receiving module within the entire range of the first angle range converge within a specified range (second structure).

[0125] In the optical displacement meter of any one of the above-mentioned structures 1 to 2, the following structure may also be adopted: the guide structure comprises a first guide member fixed to the housing and a second guide member rotating integrally with the light projecting and receiving module through the motor, and when observed along the direction of the rotation axis, the first flexible printed circuit board comprises the bent portion (structure 3) between the first guide member and the second guide member within the entire range of the first angle range.

[0126] In the optical displacement meter of any one of the above-mentioned structures 1 to 3, the following structure may also be adopted: the first flexible printed circuit board has a first portion guided along the first guide member and a second portion guided along the second guide member, and when observed along the rotation axis direction of the light projecting and light receiving module, the bent portion forms a roughly U-shape from the first portion to the second portion (structure 4).

[0127] In the optical displacement meter of any one of the above-mentioned structures 1 to 4, the following structure can also be adopted: the first guide member has a first wall surface which is arc-shaped when viewed along the rotation axis direction of the light projecting and light receiving module and is used to guide the first part; the second guide member has a second wall surface which is arc-shaped when viewed along the rotation axis direction of the light projecting and light receiving module and is used to guide the second part; the first wall surface and the second wall surface are arranged in approximately concentric circles with the rotation axis of the light projecting and light receiving module as the center (structure 5).

[0128] In the optical displacement meter of any one of the first to fifth structures, the first guide and the second guide may extend along the rotation axis direction of the light projecting and receiving module (sixth structure).

[0129] In the optical displacement meter of any one of the above-mentioned structures 1 to 6, the following structure can also be adopted: the first flexible printed circuit board electrically connects the camera unit with the fixed substrate, the light projecting and light receiving module also has a second flexible printed circuit board, the second flexible printed circuit board electrically connects the light projecting unit with the fixed substrate, the second flexible printed circuit board has a curved portion throughout the first angle range, the guiding structure causes the position of the curved portion of the second flexible printed circuit board to change along with the rotation of the light projecting and light receiving module, and causes the change in the radius of curvature of the curved portion caused by the rotation of the light projecting and light receiving module within the entire first angle range to converge within a specified range (structure 7).

[0130] In the optical displacement meter of the seventh configuration, the first flexible printed circuit board and the second flexible printed circuit board may be integrally guided by the guide structure in a state of being aligned in the rotation axis direction of the light projecting and receiving module (eighth configuration).

[0131] In the optical displacement meter of any one of the above-mentioned structures 7 to 8, the guide structure may also have a rib structure between the first flexible printed circuit board and the second flexible printed circuit board for preventing the first flexible printed circuit board from contacting the second flexible printed circuit board (9th structure).

[0132] In the optical displacement meter of any one of the above-mentioned structures 1 to 9, the following structure may also be adopted: the light projecting and receiving module is configured to be able to rotate to a second angle range outside the measurement object, which is outside the first angle range and further to the outside than the first angle range, by the rotation of the motor, and the first flexible printed circuit board also has the bending portion throughout the entire range of the second angle range (structure 10).

[0133] In the optical displacement meter of any one of the first to tenth structures, the first flexible printed circuit board may be spirally shaped and configured to be capable of at least one of twisting and stretching along the rotation axis of the light projecting and receiving module (eleventh structure).

[0134] In the optical displacement meter of any one of the above-mentioned structures 1 to 11, the following structure may also be adopted: the light projecting and light receiving module is configured to be able to rotate to a second angle range outside the measurement object, which is outside the first angle range, through the rotation of the motor, and the first flexible printed circuit board also has a bending portion throughout the entire range of the second angle range (structure 12).

[0135] In the optical displacement meter of any one of the above-mentioned structures 1 to 12, it can also be the following structure: the fixed substrate includes a contour generating unit, and the contour generating unit generates a cross-sectional contour of the workpiece at each rotation angle based on the amount of light received by the camera unit (13th structure).

[0136] In the optical displacement meter of the above-mentioned structure 13, it can also be the following structure: the optical displacement meter also has a three-dimensional data generating unit, and the three-dimensional data generating unit generates three-dimensional shape data based on the multiple cross-sectional contours obtained by rotating the light-projecting and light-receiving module, and the three-dimensional data generating unit is arranged on the light-projecting and light-receiving module or the fixed substrate (structure 14).

[0137] The following structure may also be adopted: in a measuring system comprising the optical displacement meter described in the above-mentioned 13th structure and an external device having a control unit, the optical displacement meter further comprises a communication unit, the communication unit transmits the cross-sectional profile generated by the profile generating unit to the external device, and the control unit of the external device generates three-dimensional shape data based on the multiple cross-sectional profiles received from the optical displacement meter (15th structure).

[0138] In the optical displacement meter of any one of the above-mentioned structures 1 to 12, it can also be the following structure: the fixed substrate includes a contour generating unit, and the contour generating unit generates a cross-sectional contour of the workpiece at each rotation angle based on the amount of light received by the camera unit (16th structure).

[0139] In the optical displacement meter of the above-mentioned structure 16, it can also be the following structure: the fixed substrate further includes a three-dimensional data generating unit, and the three-dimensional data generating unit generates three-dimensional shape data based on the multiple cross-sectional contours obtained by rotating the light projecting and receiving module (17th structure).

[0140] The following structure may also be adopted: in a measuring system including an optical displacement meter having the above-mentioned structure 16 and an external device having a control unit, the optical displacement meter further includes a communication unit, the communication unit sends the cross-sectional profile generated by the profile generating unit to the external device, and the control unit of the external device generates three-dimensional shape data based on the multiple cross-sectional profiles received from the optical displacement meter (structure 18).

[0141] The following structure may also be adopted: in a measuring system comprising an optical displacement meter having any one of the above-mentioned structures 1 to 12 and an external device having a control unit, the optical displacement meter further comprises a communication unit, the communication unit sends data related to the amount of light received by the camera unit to the external device, and the control unit of the external device generates a two-dimensional profile of the cross section of the workpiece at each rotation angle based on the amount of light received from the optical displacement meter (structure 19).

[0142] In the measurement system of the above-mentioned structure 19, it can also be the following structure: the communication unit of the optical displacement meter sends the multiple cross-sectional profiles obtained by the rotation of the light-projecting and light-receiving module to the external device, and the control unit of the external device generates three-dimensional shape data based on the multiple cross-sectional profiles received from the optical displacement meter (structure 20).

[0143] <Other Modifications>

[0144] In addition, in addition to the above-mentioned embodiments, various technical features disclosed in this specification can be subjected to various changes within the scope of the main purpose of the technical design. That is, the above-mentioned embodiments should be considered to be illustrative rather than restrictive in all aspects, and it should be understood that the protection scope of the utility model is defined by the claims, including all changes within the meaning and scope equivalent to the claims.

[0145] Description of Reference Numerals

[0146] 1: optical displacement meter; 2: control device; 3: display device; 4: input device; 10: housing; 11: light-projecting unit; 12: light-receiving lens; 13: camera unit; 14: light source; 15: light-projecting lens; 16: light-projecting window; 17: light-receiving window; 18: reflecting member; 20: light-projecting and light-receiving module; 201: base member; 21: motor; 22: control unit; 23: motor control unit; 24: signal processing unit; 25: communication unit; 26: peak detection unit; 27: contour generation unit; 28: Three-dimensional data generating unit; 30: fixed substrate; 31: first flexible printed circuit board; 311: bending portion; 312: first portion; 313: second portion; 32: imaging substrate; 33: first guide member; 331, 332, 333: rib structure; 34: second guide member; 35: projection substrate; 36: second flexible printed circuit board; 100: optical displacement measuring system; AX1: projection axis; AX2: optical axis; I1: image; AX3: rotation axis; R1: area; W: workpiece.

Claims

1. An optical displacement meter, characterized in that: have: a light projecting and receiving module having a light projecting unit for irradiating a workpiece with slit light extending in the X direction, a light receiving lens for converging reflected light from the workpiece, and an imaging unit for receiving the light converging through the light receiving lens; A motor, which rotates the light-projecting and light-receiving modules integrally; A housing, which accommodates the light-projecting and light-receiving module; A fixed substrate, which is fixed to the housing; as well as a first flexible printed circuit board, which connects the light-projecting and light-receiving module to the fixed substrate; The first flexible printed circuit board has a curved portion throughout a first angle range of a measurement target of the light projecting and receiving module.

2. The optical displacement meter according to claim 1, characterized in that: It also has a guiding structure, which is used to change the position of the bent portion of the first flexible printed circuit board along with the rotation of the light projecting and receiving module, and to make the change in the curvature radius of the bent portion caused by the rotation of the light projecting and receiving module within the entire range of the first angle range converge within a specified range.

3. The optical displacement meter according to claim 2, characterized in that: The guide structure includes a first guide member fixed to the housing and a second guide member that is rotated integrally with the light projecting and receiving module by the motor. When viewed along the rotation axis direction of the light projecting and receiving module, the first flexible printed circuit board has the bent portion over the entire range of the first angle between the first guide and the second guide.

4. The optical displacement meter according to claim 3, characterized in that: The first flexible printed circuit board has a first portion guided along the first guide member and a second portion guided along the second guide member, When viewed along the rotation axis direction of the light projecting and receiving module, the curved portion forms a substantially U-shape from the first portion to the second portion.

5. The optical displacement meter according to claim 4, characterized in that: The first guide has a first wall surface which is arc-shaped when viewed along the rotation axis direction of the light projecting and receiving module and is used to guide the first portion. The second guide has a second wall surface which is arc-shaped when viewed along the rotation axis direction of the light projecting and receiving module and is used to guide the second portion. The first wall surface and the second wall surface are arranged in substantially concentric circles with the rotation axis of the light projecting and receiving module as the center.

6. The optical displacement meter according to claim 5, characterized in that: The curvature radius of the second wall surface is smaller than the curvature radius of the first wall surface and larger than the curvature radius of the bent portion of the first flexible printed circuit board.

7. The optical displacement meter according to claim 2, characterized in that: The first flexible printed circuit board electrically connects the imaging unit and the fixed substrate. The light projecting and receiving module further comprises a second flexible printed circuit board, the second flexible printed circuit board electrically connects the light projecting unit to the fixed substrate, and the second flexible printed circuit board has a curved portion within the entire range of the first angle range. The guiding structure causes the position of the bent portion of the second flexible printed circuit board to change along with the rotation of the light projecting and receiving module, and causes the change in the radius of curvature of the bent portion caused by the rotation of the light projecting and receiving module within the entire range of the first angle range to converge within a specified range.

8. The optical displacement meter according to claim 7, characterized in that: The first flexible printed circuit board and the second flexible printed circuit board are integrally guided by the guide structure in a state where they are aligned in the direction of the rotation axis of the light projecting and receiving module.

9. The optical displacement meter according to claim 8, characterized in that: The guide structure further has a rib structure between the first flexible printed circuit board and the second flexible printed circuit board for preventing the first flexible printed circuit board from contacting the second flexible printed circuit board.

10. The optical displacement meter according to claim 1, characterized in that: The light projecting and receiving module is configured to be rotatable to a second angle range outside the first angle range and outside the measurement target by the rotation of the motor. The first flexible printed circuit board also has the bent portion throughout the second angle range.

11. The optical displacement meter according to claim 1, characterized in that: The first flexible printed circuit board has a spiral shape and is configured to be capable of at least one of twisting and extending and contracting along a rotation axis of the light projecting and receiving module.

Images