JPWO2019083009A1 - Inspection system and inspection method - Google Patents

Abstract

The inspection system (1) includes a hollow inspection head (10) extending in a rod shape along the central axis (11), a rotating unit (20) that rotates the inspection head around the central axis, and an inspection head (10). An optical system (30) that supplies laser light for inspection along the central axis (11) through the inside and receives reflected light from the surface (4) of the object (2) to be inspected returned along the central axis. ), And an optical element (50) arranged near or near the tip of the inspection head, which emits a laser beam for inspection toward the object to be inspected and guides the reflected light in the central axis direction. The optical element includes a reflective surface whose normal line can be tilted at an angle θ with respect to the central axis, and the angle θ satisfies the following conditions. 46 degrees ≤ θ ≤ 55 degrees

Description

The present invention relates to an inspection system and method for inspecting a surface by irradiating an object to be inspected with a laser beam for inspection from an inspection head.

According to Japanese Patent Application Laid-Open No. 11-281583, when the object to be inspected has a cylindrical shape, the inner peripheral surface thereof can be easily inspected, and when the surface of the object to be inspected is flat, one movement is required. A surface inspection device capable of taking a wide area that can be inspected is disclosed. In this surface inspection device, the armature shaft of the electric motor is a hollow cylinder, and a fiber holding cylinder that binds and holds the optical fiber and the light receiving fiber is loosely inserted inside the armature shaft, and a rotating cylinder is integrated with the tip of the armature shaft. Attach to. Inside the rotating cylinder, an optical path changing means for changing the optical path of the inspection light and the reflected light with respect to the axis of the fiber holding cylinder, for example, at a right angle, and a light path changing means for collecting the inspection light on the object to be inspected and reflected light A light collecting means for collecting light on the light receiving fiber is installed. When the electric motor is operated to rotate the rotating cylinder together with the armature shaft, the optical path changing means installed inside the electric motor rotates, and the area to be inspected by irradiating the inspection light can be moved.

It is possible to inspect the inner surface of the cylinder of the object to be inspected by an inspection device that inspects the surface by irradiating the inspection light from the rotating cylinder in the direction orthogonal to the axis. However, it is necessary to install a means for changing the angle of the optical path of the inspection light, for example, a reflector, at the tip of the rotating cylinder. Therefore, since a space for installing a reflector is required, when inspecting the inner surface of a bottomed cylinder, inspect the part near the bottom surface of the inner surface of the cylinder, and even the boundary between the inner surface of the cylinder and the bottom surface. Was impossible.

One aspect of the present invention is a hollow inspection head extending in a rod shape along the central axis, and an inspection head rotated around the central axis and a laser for inspection along the central axis through the inspection head. It has an optical system that supplies light and receives reflected light from the surface to be inspected (surface) of the object to be inspected that has been returned along the central axis, and an optical element that is located near or at the tip of the inspection head. It is an inspection system. An optical element is an optical element that emits laser light for inspection toward an object to be inspected and guides reflected light in the direction of the central axis, and is used for inspection with the normal line tilted at an angle θ with respect to the central axis. The angle θ satisfies the following condition (1), including a reflecting surface capable of emitting the laser light of.
46 degrees ≤ θ ≤ 55 degrees ... (1)

This inspection system has a hollow inspection head extending in a rod shape along the central axis, a rotating unit that rotates the inspection head around the central axis, and a laser beam for inspection along the central axis through the inside of the inspection head. The optical element has an optical system that receives the reflected light from the surface to be inspected of the object to be inspected that has been supplied and returned along the central axis, and an optical element arranged near or near the tip of the inspection head. , The laser beam for inspection may be emitted toward the surface to be inspected at an angle φ with respect to the central axis, and the reflected light may be guided in the direction of the central axis. The angle φ satisfies the following condition (2).
92 degrees ≤ φ ≤ 110 degrees ・ ・ ・ (2)

In this inspection system, the inventor of the present application emits a laser beam for inspection in a non-right angle direction by an optical element and irradiates the surface of the object to be inspected at a non-right angle from the surface of the inspected object. Although the intensity of the reflected light is reduced, it was found that the reflected light can be captured with sufficient intensity to analyze the surface condition. Therefore, the inspection system can detect the state of the non-inspected surface by emitting the laser beam for inspection at a non-right angle toward the surface to be inspected parallel to the central axis by the optical element. In the range of condition (1), the intensity of the reflected light may be reduced to about 1/10 as compared with the case where the angle θ is 45 degrees, that is, the angle φ is 90 degrees, but the surface condition is analyzed. It is possible to obtain reflected light containing the minimum necessary information.

The upper limit of the condition (1) may be 53.5 degrees or 52 degrees because the intensity of the reflected light can be secured. Similarly, the upper limit of the condition (2) may be 107 degrees or 104 degrees. The lower limit of the condition (1) may be 48 degrees or 50 degrees because the boundary of the inspectable side surface can be brought closer to the bottom surface. Similarly, the lower limit of the condition (2) may be 96 degrees or 100 degrees.

This inspection system may include a unit that varies the angle θ, that is, the angle φ. It may have an opening provided so as to reach the tip from the vicinity of the tip of the inspection head. Further, the inspection system may have a rotating unit that rotates the inspection head around a central axis. The inspection system may further include a moving unit that moves the inspection head relative to the subject to be inspected, including a hollow portion or recess into which the inspection head is inserted, along a central axis.

One other aspect of the present invention is a hollow inspection head extending rod-shaped along a central axis, using an inspection system that includes an inspection head that is rotated around the central axis. It is a method having to inspect the condition of the surface to be inspected. The inspection system is an optical system that supplies laser light for inspection along the central axis through the inside of the inspection head and receives the reflected light from the surface to be inspected returned along the central axis, and the vicinity of the tip of the inspection head. Alternatively, it further includes an optical element arranged at the tip thereof, which emits a laser beam for inspection toward the object to be inspected and guides the reflected light in the central axis direction. Further, the inspection includes emitting a laser beam for inspection toward the surface to be inspected with the normal line tilted at an angle θ with respect to the central axis of the reflecting surface of the optical element, and the angle θ Satisfies the above condition (1). Emitting may include changing the angle θ.

One of yet different other aspects of the present invention is a method comprising inspecting the condition of the surface to be inspected of an object to be inspected using an inspection system including an inspection head, wherein the inspection is an optical element. This is a method including emitting a laser beam for inspection toward the surface to be inspected at an angle φ with respect to the central axis. The angle φ satisfies the above condition (2).

In these inspection methods, the emission may include emitting a laser beam for inspection toward a surface to be inspected parallel to the central axis. Emission also includes emitting laser light for inspection toward the surface to be inspected (inner surface, surface) parallel to the central axis of the hollow portion or recess extending along the central axis of the object to be inspected. It may be.

The perspective view which shows the outline of the inspection apparatus. Sectional drawing (II-II sectional view) which shows the schematic structure of the inspection apparatus. The perspective view which shows the outline of the inspection head. FIG. 5 is a cross-sectional view (IV-IV cross-sectional view) showing a schematic configuration of an inspection head. FIG. 5 is a cross-sectional view showing the configuration of the tip of the inspection head shown in FIG. 4 in an enlarged manner. The figure which shows some example of the shape of the opening of the tip of an inspection head. The figure which shows the measurement result of the average density ratio of the reflected light. The flowchart which shows an example of the inspection method using an inspection apparatus.

Embodiment of the invention

FIG. 1 shows the appearance of the inspection device (inspection system) 1, and FIG. 2 shows a schematic configuration of the inspection device 1 using a cross section. This inspection device (surface inspection device) 1 is suitable for inspecting the shape or state of the inner surface (surface, surface to be inspected) 4 of the hollow portion 3 such as holes and dents provided in the object to be inspected 2. An example of the hollow portion 3 is a bottomed hollow portion 3 having a cylindrical side surface 4a and a bottom surface 4b.

The inspection device 1 is centered through a hollow inspection head (inspection probe) 10 extending in a rod shape along the central axis 11, a rotating unit 20 for rotating the inspection head 10 around the central axis 11, and the inside of the inspection head 10. An optical system 30 that supplies laser light for inspection along the axis 11 and receives reflected light from the surface (surface to be inspected) 4 of the object to be inspected 2 returned along the central axis 11 and an inspection head 10. An optical element 50 arranged at or near the tip of the device, a moving unit 25 that relatively moves at least one of the inspection head 10 and the object 2 to be inspected along the central axis 11, a rotating unit 20, an optical system 30, and an optical system 30. Includes a housing 5 containing a moving unit 25.

The inspection device 1 includes a moving unit 25 of the inspection head 10 housed in the housing 5 as a moving unit 25 that relatively moves the inspection head (inspection probe) 10 and the object 2 to be inspected. The moving unit 25 includes a carriage 28 equipped with an inspection head 10, a rotating unit 20, and an optical system 30, and a combination of a ball screw 26 for moving the carriage 28 back and forth (left and right in FIG. 2) and a moving motor 27. The inspection head 10 includes a fixing portion 19 as a base end and a rotating portion 18 mounted so as to rotate with respect to the fixing portion 19, and the fixing portion 19 is mounted on the carriage 28 via a holder 29. .. The configuration of the moving unit 25 is an example, and may be a slider, a moving table, or the like. The moving unit 25 moves the inspection head 10 to a position P1 protruding forward from the housing 5 and a position P2 where the inspection head 10 retracts inside the housing 5. The object 2 to be inspected may be moved by using a robot or the like instead of the inspection head 10 or together with the inspection head 10.

The optical system 30 drives a semiconductor laser (laser diode, LD) 31 that generates laser light for inspection, a light receiving element (for example, a photodiode, CCD, CMOS, etc.) 32 that receives reflected light, and a semiconductor laser 31. It includes a control unit 33 including a circuit, a circuit for processing a signal received by the light receiving element 32, and the like. The signal received by the optical system 30 is sent to a computer (personal computer) (not shown) via the control unit 33, further processed into data, and used for analysis of the surface 4 of the object 2 to be inspected. The optical system 30 further includes an optical fiber 35 inserted inside the inspection probe 10 and a dimming lens 36 that controls the light flux input / output to / from the optical fiber 35. These will be further described below.

An example of the rotating unit 20 is a motor 21 mounted on the carriage 28. The pulley 22 driven by the motor 21 is connected to the rotating portion 18 of the inspection head 10 by the drive belt 23, and the motor 21 moves the rotating portion 18 of the inspection head 10 around the central axis 11 via the drive belt 23. It rotates at high speed (with the central axis 11 as the center of rotation).

FIG. 3 shows the inspection head (inspection probe) 10 extracted. FIG. 4 shows a schematic configuration of the probe 10 using a cross section. The inspection head 10 is a hollow cylinder extending along the rotation shaft 11 as a whole, and is coaxially attached to the fixing portion 19 at the base end and the fixing portion 19 so as to rotate via the bearing 17. , The rotating portion 18 extending toward the tip direction (forward) 16. The rotating portion 18 includes a relatively thick driving portion 15 to which a rotational force is transmitted via the driving belt 23, and an insertion portion (needle) 14 extending from the driving unit 15 toward the tip (front) 16. .. The tip 14a of the insertion portion 14 is provided with an opening (notch) 13 facing in the radial direction, and laser light (probe light) for inspection is emitted from the inspection head 10 through the opening 13 to be inspected. The reflected light from the surface 4 of the object 2 is returned to the inspection head 10.

FIG. 5 shows a state in which the inner surface 4 of the hollow portion 3 to be inspected of the object 2 to be inspected is inspected by the light emitted from the inspection head 10. Laser light (probe light) 61 for inspection is emitted from the opening 13 of the inspection head 10 toward the inner surface (inspection target surface) 4, and the reflected light 62 from the inspection target surface 4 is emitted from the opening 13 into the inside of the inspection head 10. Be returned.

An optical fiber 35 that guides the probe light 61 and the reflected light 62 along the central axis 11 is inserted inside the inspection head 10. The optical fiber 35 constituting the optical system 30 is a bundle of a plurality of fibers, and receives the optical fiber 35a that guides the probe light 61 emitted from the LD 31 toward the object 2 to be inspected and the reflected light 62 from the object 2 to be inspected. Includes a light receiving fiber 35b leading to the element 32. Further, the optical system 30 includes a holding cylinder 34 that holds the optical fibers 35 in a bundled state inside the inspection head 10, and a photochromic lens 36 provided at the tip of the holding cylinder 34.

The insertion portion 14 at the tip of the inspection head 10 extends coaxially so as to cover the holding cylinder 34 and the photochromic lens 36, and the probe light 61 is located at the tip (near the tip) 14a of the insertion portion 14 at the front 16 of the photochromic lens 36. An optical element 50 for controlling the emission direction of the lens 50 is arranged. An example of the optical element 50 is a plane mirror, which may be an optical element having a reflecting surface capable of controlling the emission direction and the incident direction of other light such as a prism. In the inspection device 1 of this example, the angle θ of the mirror surface (reflection surface) 51, specifically, the angle (diagonal angle, acute angle side angle) θ formed by the normal line 55 orthogonal to the reflection surface 51 with the central axis 11. It can be set to 46 degrees or more. As a result, the probe light 61 emitted from the optical fiber 35 extending along the central axis 11 with the central axis 11 as the optical axis is directed forward 16 with respect to the central axis (optical axis) 11, that is, with respect to the central axis 11. The light is emitted toward the front 16 at an angle φ larger than the orthogonal direction. The angle θ of the reflecting surface 51 may be fixed, and may be variable from 45 degrees or less than 45 degrees to 45 degrees or more by using a small and appropriate actuator 59 such as a micromotor or a piezo element capable of controlling the angle. May be good.

The optical element 50 whose angle θ of the reflecting surface 51 is tilted at an angle θ of 46 degrees or more directs the reflected light 62 of the front inspection target surface 4 irradiated by the probe light 61 emitted toward the front 16 toward the central axis 11. It includes a function of reflecting and guiding to the optical fiber 35. The photochromic lens 36 is an objective lens having a focal length suitable for condensing the probe light 61 output from the tip 35c of the optical fiber 35 onto the inspection target surface 4 via the reflection surface 51. The photochromic lens 36 also includes a function of condensing the reflected light 62 introduced into the inspection head 10 via the reflecting surface 51 onto the tip 35c of the optical fiber 35. The optical system 30 that emits the probe light 61 along the central axis 11 of the inspection head 10 and detects the reflected light 62 is not limited to the one using the optical fiber 35, but may be an optical pickup or the like equipped with a dichroic prism or the like. It may be another known optical system. When the diameter of the hollow portion 3 to be inspected is several cm or less or several mm or less, the optical system 30 using the optical fiber 35 is suitable.

FIG. 6 shows some examples of the opening (notch) 13 provided at the tip 14a of the insertion portion 14 at the front 16 of the inspection head 10. The opening 13 of the inspection head 10 shown in FIG. 6A provided at the tip (near the tip) 14a of the insertion portion 14 has a U-shape in which the direction of the edge 14e of the tip (tip) of the insertion portion 14 is open. Is. As shown in the cross section in FIG. 6B, the opening 13 includes at least a point (center) 51c where the reflecting surface 51 intersects the central axis (optical axis) 11 and reaches the edge 14e toward the front 16. It has become. Therefore, the probe light 61 reflected forward by the reflecting surface 51 and the reflected light 62 from the front 16 enter the inside of the inspection head 10 without interfering with the wall surface (housing, sheath) of the insertion portion 14. It is output.

The opening 13 provided at the tip 14a of the insertion portion 14 of the inspection head 10 shown in FIG. 6C is a U-shape in which the direction of the edge 14e of the insertion portion 14 is open, and is shown in FIG. 6D. As described above, the opening reaches the edge 14e of the insertion portion 14 including the intersection 51c between the reflecting surface 51 and the central axis 11. The shape of the opening 13 is not limited to these, and an optical element 50 such as a mirror may be mounted so as to protrude forward 16 from the tip of the insertion portion 14. In the inspection head 10, in order to continuously irradiate the cylindrical inspection target surface 4 with the probe light 61 in a circumferential shape, the optical element 50 is placed around the central axis 11 at high speed around the central axis 11. , It is necessary to rotate in a stable state. Therefore, the configuration in which the optical element 50 is fixed while being inserted into the tip 14a of the cylindrical insertion portion 14 and the probe light 61 and the reflected light 62 are handled with a part of the tip 14a as an opening (notch) 13 is an inspection head. It is one of the suitable configurations as 10.

In the inspection head 10 used in the inspection device 1, it is necessary to arrange the optical element 50 at the tip end or near the tip end 14a to change the emission direction of the probe light 61 from the direction of the central axis 11 to the radial direction. Therefore, when the hollow portion 3 having the bottom surface 4b as shown in FIG. 5 is targeted for inspection, the optical element 50 is installed in addition to the clearance for avoiding interference between the inspection head 10 and the object to be inspected 2. The space required for this is the dead space DS. Therefore, in the type in which the reflecting surface 51 is arranged at 45 degrees with respect to the central axis 11 and the probe light 61 is emitted in the direction of 90 degrees with respect to the central axis 11 as in the conventional inspection head 10, the inspection target is There is a problem that the surface of the dead space DS portion close to the bottom surface 4b of the peripheral surface 4a cannot be inspected.

On the other hand, in the inspection head 10, as shown in an enlarged view in FIG. 5, the angle θ of the reflecting surface 51 is set (arranged) to 46 degrees or more, and the irradiation angle φ with respect to the central axis 11 of the probe light 61 is 92. The dead space DS, which cannot be inspected, is reduced or eliminated from the peripheral surface 4a by irradiating the peripheral surface 4a toward the front 16.

The inventor of the present application has an inspection target surface (inspection surface) 4a parallel to the central axis 11 even if the probe light 61 is irradiated to the front 16 instead of the direction orthogonal to the central axis 11, for example, the center. It has been found that the reflected light 62 can be obtained from the cylindrical inner surface 4a centered on the shaft 11. Further, it has been found that if the intensity of the reflected light 62 is sufficient, the state including the unevenness of the inspection target surface 4a can be inspected. Further, when the average density value of the reflected light 62 is less than about 1/10 of the time when the probe light 61 having the highest intensity is emitted so as to be orthogonal to the central axis 11, the amount of data for image processing increases. It was found that there was a shortage and it was difficult to obtain the information necessary for surface inspection.

FIG. 7 shows a change in the ratio (average density ratio) of the average density values of the reflected light 62 when the angle θ of the reflecting surface 51 is changed. In this measurement, the reflection that can be obtained by changing the angle (tilt angle) β of the surface 4 that is the inspection target (measurement target) instead of directly changing the angle θ of the reflection surface 51 mounted on the inspection head 10. The average concentration value of the light 62 is measured, and the value with an inclination angle β of 0 is taken as 100 and shown as%. The laser output used for the measurement is 300 μW, and the spot diameter is about 50 μm.

The relationship between the angle θ of the reflecting surface 51, the irradiation angle φ of the probe light 61, and the inclination angle β is expressed by the following equations (3) and (4).
φ = 2 × θ ・ ・ ・ (3)
β = 2 × θ-90 ・ ・ ・ (4)

Further, the distance Lc in the central axis direction of the intersection 51c of the reflection surface 51 with the central axis 11 and the point that can be irradiated by the probe light 61 and the distance Lr in the radial direction from the central axis 11 are expressed by the following equation (6). It is represented by.
Lc / Lr = tan (2 × θ-90) ・ ・ ・ (5)

From the measurement results of FIG. 7, it can be seen that when the inclination angle β exceeds 20 degrees, the average concentration ratio falls below about 9%. Therefore, it is desirable that the angle θ of the reflecting surface 51 is 55 degrees or less (the irradiation angle φ is 110 degrees or less). In particular, when the inclination angle β exceeds 20 degrees, the attenuation rate of the average concentration ratio becomes large. Further, from the viewpoint of reducing the dead space DS, it is desirable that the angle θ is 46 degrees or more. Therefore, it is desirable that the angle θ of the reflecting surface 51 is 46 degrees or more and 55 degrees or less, as shown in the equation (1). Further, it is desirable that the irradiation angle φ of the probe light 61 is 92 degrees or more and 110 degrees or less as shown in the equation (2). Under this condition, if Lc / Lr is 0.36, the inner diameter of the hollow portion 3 to be inspected is 30 mm, the diameter of the inspection head 10 is about 14 mm, and the dead space DS is 5 mm, the hollow portion 3 to be inspected The peripheral surface 4a can be inspected up to the boundary 4c of the bottom surface 4b.

As shown in the measurement result of FIG. 7, when the angle θ of the reflecting surface 51 is 53.5 degrees or less, the irradiation angle φ is 107 degrees or less, the average concentration ratio exceeds 33%, and the intensity of the reflected light 62 It is possible to secure 1/3 or more of the maximum strength. Therefore, it is possible to provide an inspection head 10 and an inspection head 10 which have a wide inspection range and a high intensity of reflected light 62, which are more suitable for surface inspection. At this time, Lc / Lr is 0.31, and under the above conditions, the peripheral surface 4a can be sufficiently inspected up to the boundary of the bottom surface 4b.

Further, when the angle θ of the reflecting surface 51 is 52 degrees or less, the irradiation angle φ is 104 degrees or less, the average concentration ratio exceeds 50%, and the intensity of the reflected light 62 can be 1/2 or more of the maximum intensity. .. Therefore, it is possible to provide an inspection head 10 and an inspection head 10 which have a wide inspection range and a higher intensity of the reflected light 62, which are more suitable for surface inspection. Lc / Lr at this time is 0.25, and under the above conditions, the peripheral surface 4a can be sufficiently inspected up to the boundary 4c of the bottom surface 4b.

Further, when the angle θ of the reflecting surface 51 is 50 degrees or less, the irradiation angle φ is 100 degrees or less, and the average concentration ratio exceeds 65%. Therefore, the reflected light 62 having a higher intensity can be obtained, and the inspection head 10 and the inspection head 10 more suitable for the surface inspection can be provided. At this time, Lc / Lr is 0.18, and under the above conditions, the peripheral surface 4a can be sufficiently inspected up to the boundary 4c of the bottom surface 4b.

The lower limit of the angle θ of the reflecting surface 51 may be such that the probe light 61 can be irradiated at a non-90 degree (non-right angle), the angle θ may exceed 45 degrees, and the irradiation angle φ may also exceed 90 degrees. .. However, considering the reduction of dead space DS, it is desirable that the angle θ is 46 degrees or more (irradiation angle φ is 92 degrees), and the angle θ is 48 degrees (irradiation angle φ is 96 degrees) or more. Is desirable. Further, considering the inspection of the entire peripheral surface 4a of the hollow portion 3 as described above, the angle θ is preferably 49 degrees (irradiation angle φ is 98 degrees) or more, and the angle θ is 50 degrees (irradiation). The angle φ is more preferably 100 degrees) or more.

Further, in the inspection device 1, the inspection head 10, and the inspection method using them, the surface to be inspected is irradiated with the probe light 61 at a non-right angle to the surface 4 to be inspected so that the surface to be inspected is parallel to the central axis. Even if it continues to, the inspectable range can be expanded. As described above, the angle (tilt angle) β formed by the surface 4 to be inspected and the probe light 61 is preferably 20 degrees or less, more preferably 17 degrees or less, and more preferably 14 degrees or less. Is even more preferable. Further, considering expanding the inspection range, the inclination angle β is preferably 2 degrees or more, more preferably 6 degrees or more, and it is also effective that the inclination angle β is 10 degrees or more.

FIG. 8 shows an example of a method of inspecting the surface (inspected surface) of the inspection object (inspection object) using the inspection device 1. An example of the surface to be inspected (surface to be inspected) 4 is a bottomed and hollow cylindrical surface, for example, an inner surface (side surface) of a cylinder. In step 111, the angle θ of the reflecting surface 51 is set to 45 degrees, and the irradiation angle φ of the probe light 61 is set to 90 degrees. The angle θ of the reflecting surface 51 does not have to be 45 degrees, but it is preferable to adopt an angle θ having a high average concentration ratio in a normal inspection. In step 112, the inspection head 10 is inserted into the hollow portion to be inspected, and the inspection of the side surface (inner surface, surface to be inspected) 4a of the hollow portion 3 is started. In step 113, when the inspection head 10 reaches the deepest portion, that is, a position where a predetermined clearance can be secured with respect to the bottom surface 4b of the hollow portion 3, in step 114, the actuator 59 is used to adjust the angle θ of the reflecting surface 51 to 46. The inspection of the side surface 4a of the hollow portion 3 is continued by changing the irradiation angle φ of the probe light 61 to 92 degrees or more by continuously or intermittently changing the degree or more. When the boundary 4c between the side surface 4a and the bottom surface 4b is detected in step 115, the inspection ends.

In the inspection method using the inspection device 1, instead of making the angle θ of the reflection surface 51 variable, in step 111, the angle θ of the reflection surface 51 is set in advance at an angle at which the boundary 4c can be detected at the deepest portion, and the probe light is used. Even if the irradiation angle of 61 is set to 92 degrees or more in advance, the side surface 4a is inspected while the inspection head 10 is gradually inserted into the hollow portion 3, and the inspection is terminated when the boundary 4c is detected. Good. By such a method, even in the hollow portion 3 in which the side surface 4a parallel to the central axis 11 continues to the boundary 4c with the bottom surface 4b, the side surface 4a is irradiated with the probe light 61 up to the boundary 4c to reach the side surface. The condition of 4a can be inspected.

As described above, in the inspection device (inspection system) 1 according to the present invention, the inspection light (probe light) 61 is directed forward 16 in the non-90 degree direction from the tip 14a of the inspection head (inspection probe) 10. It can be directed and irradiated. Therefore, the dead space of the inspection head 10 can be eliminated or reduced. Therefore, by inspecting the peripheral surface 4a of the hollow space 3 provided with the bottom surface 4b by the inspection system 1, the peripheral surface 4a is inspected up to the bottom surface 4b or even closer to the bottom surface 4b, and the state of the surface is inspected. Can be evaluated.

Claims (15)

A hollow inspection head extending in a rod shape along the central axis and rotating around the central axis.
An optical system that supplies laser light for inspection along the central axis through the inspection head and receives reflected light from the surface to be inspected of the object to be inspected returned along the central axis.
An optical element arranged near or near the tip of the inspection head, which emits the laser light for inspection toward the object to be inspected and guides the reflected light in the central axis direction. And
The optical element includes a reflective surface capable of emitting a laser beam for inspection toward the surface to be inspected in a state where the normal line is tilted at an angle θ with respect to the central axis, and the angle θ is as follows. An inspection system that meets the conditions.
46 degrees ≤ θ ≤ 55 degrees In claim 1,
An inspection system in which the angle θ satisfies the following conditions.
48 degrees ≤ θ ≤ 53.5 degrees In claim 2,
An inspection system in which the angle θ satisfies the following conditions.
50 degrees ≤ θ ≤ 52 degrees In any of claims 1 to 3,
An inspection system having a unit that changes the angle θ. A hollow inspection head extending in a rod shape along the central axis,
A rotating unit that rotates the inspection head around the central axis,
An optical system that supplies laser light for inspection along the central axis through the inspection head and receives reflected light from the surface to be inspected of the object to be inspected returned along the central axis.
An optical element arranged near or near the tip of the inspection head, which emits the laser light for inspection at an angle φ toward the surface to be inspected and emits the reflected light with respect to the central axis. An inspection system having an optical element that guides in the central axis direction, and the angle φ satisfies the following conditions.
92 degrees ≤ φ ≤ 110 degrees In claim 5,
An inspection system having a unit for varying the angle φ. In any of claims 1 to 6,
An inspection system having an opening provided so as to reach the tip from the vicinity of the tip of the inspection head. In any of claims 1 to 7, further
An inspection system having a rotating unit that rotates the inspection head around the central axis. In any of claims 1 to 8,
The object to be inspected includes a hollow portion or a recess into which the inspection head is inserted.
An inspection system further comprising a moving unit that relatively moves the inspection head and the object to be inspected along the central axis. In any of claims 1 to 9,
An inspection system in which the optical element emits a laser beam for inspection toward the surface to be inspected parallel to the central axis. Inspecting the condition of the surface to be inspected by using an inspection system that is a hollow inspection head extending in a rod shape along the central axis and includes an inspection head that is rotated around the central axis. How to have
The inspection system includes an optical system that supplies laser light for inspection along the central axis through the inspection head and receives reflected light from the surface to be inspected returned along the central axis. An optical element arranged near or near the tip of the inspection head, which further includes an optical element that emits the laser light for inspection toward the object to be inspected and guides the reflected light in the central axis direction. And
The inspection is
The reflection surface of the optical element includes emitting laser light for inspection toward the surface to be inspected in a state where the normal line is tilted at an angle θ with respect to the central axis, and the angle θ is as follows. A method that meets the conditions of.
46 degrees ≤ θ ≤ 55 degrees 11.
The exiting method comprises changing the angle θ. Inspecting the condition of the surface to be inspected by using an inspection system that is a hollow inspection head extending in a rod shape along the central axis and includes an inspection head that is rotated around the central axis. How to have
The inspection system includes an optical system that supplies laser light for inspection along the central axis through the inspection head and receives reflected light from the surface to be inspected returned along the central axis. It has an optical element that emits the laser light for inspection toward the object to be inspected and guides the reflected light in the central axis direction.
The inspection is
A method in which the optical element emits a laser beam for inspection with respect to the central axis toward the surface to be inspected at an angle φ, and the angle φ satisfies the following conditions.
92 degrees ≤ φ ≤ 110 degrees In any of claims 11 to 13,
The method comprising emitting a laser beam for inspection toward the surface to be inspected parallel to the central axis. In any of claims 11 to 13,
The emission includes emitting a laser beam for inspection toward the surface to be inspected parallel to the central axis of a hollow portion or a recess extending along the central axis of the object to be inspected. Method.

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