JP2019128151A - Surface inspection device - Google Patents

Abstract

To provide a surface inspection device with which it is possible to inspect the surface of an area to be inspected in a short time with high accuracy.SOLUTION: A control unit 30 controls the imaging timing of an imaging unit so that, with a bright part B11 projected first to an area CP to be inspected being at the front end in the movement direction of the area CP to be inspected defined as first imaging timing, the bright part is projected to a portion of the area CP to be inspected other than the portion where the bright part is projected with previous imaging timing by each bright system, and the bright part is projected to the whole of the area CP to be inspected without a gap, and further the bright part of each bright part system is projected at a position shifted from the bright parts of other bright part systems by an amount smaller than the width of the bright part.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a surface inspection apparatus that inspects a region to be inspected by illuminating and inspecting the region to be inspected.

  A conventional inspection apparatus for inspecting defects in a region to be inspected is disclosed in Patent Document 1. In the surface defect inspection apparatus shown in Patent Document 1, the stripe pattern reflected on the surface to be inspected is input by the stripe input unit by the stripe pattern forming unit. The stripe pattern forming means includes an illumination means in which a plurality of illuminations are arranged in a line. The plurality of lights of the lighting means are controlled to be turned on and off for each row by the control means. The control means controls lighting of the lighting means to turn on and off so that the number of stripes in the stripe pattern inputted by the stripe input means becomes constant based on the moving speed of the inspection surface. Thus, by controlling the lighting and extinguishing of the illumination by the control means, the number of stripes is the same whether the inspection surface is flat or curved but defects can be detected in a stable state. It is.

JP 2000-9454 A

  In the surface defect inspection apparatus described in Japanese Patent Laid-Open No. 2000-9454, the measurement is repeatedly performed until the measurement of all the measurement points on the surface to be inspected is finished while the stripe width is constant, that is, one surface to be inspected Multiple measurements are required to inspect all measurement points. Therefore, the time required to measure the surface to be inspected becomes long.

  Then, an object of this invention is to provide the surface inspection apparatus which can test | inspect the surface of a to-be-inspected area | region accurately and in a short time.

  In order to achieve the above object, according to the surface inspection apparatus of the present invention, an illumination unit for emitting illumination light to form a projection pattern on the surface of an inspection area, and an object relatively moved with respect to the illumination unit And a control unit configured to control an imaging timing of the imaging unit so as to capture the inspection area each time the inspection area moves by a predetermined distance. A plurality of bright portions and a plurality of dark portions that are darker than the bright portions are alternately arranged in the moving direction of the region to be inspected, and the projection pattern includes one or more bright portions. A plurality of sets, and the control unit sets the first imaging timing when the bright part first projected on the inspected area is at the front end in the moving direction of the inspected area. The inspection area at the imaging timing of The bright part is projected onto a part other than the part where the bright part is projected, and the bright part is projected onto all surfaces of the inspection area. Further, the bright part of each bright part system is another bright part. The photographing timing of the photographing unit is controlled so that the bright part of the system is projected at a position shifted by a width smaller than the width of the bright part.

  With this configuration, when the inspection area passes through the illumination unit and the imaging unit one time, it is possible to obtain imaging data in which the bright part by the light irradiation is projected over the entire inspection area. As a result, it is not necessary to inspect a plurality of times at different timings, and the time required for the inspection can be shortened and the processing can be reduced.

  Further, since the bright part is projected at different positions at different timings for each bright part system, it is possible to obtain photographing data obtained by laying a plurality of bright parts substantially in one pass. This makes it possible to increase the test redundancy and the robustness.

  Furthermore, in the surface inspection apparatus, an abnormality near the center of the portion where the bright part is projected is easily detected. In the surface inspection apparatus according to the present invention, the area where the abnormality is likely to be detected is shifted by shifting the projection area of the bright part for each bright part system. Thereby, the abnormality of the surface of a to-be-inspected area | region can be detected with high precision.

  In the above configuration, the distance between the bright portions arranged at both ends of the projection pattern is shorter than the length of the inspection area. With this configuration, it is possible to eliminate an area in which a bright portion is not projected at the time of shooting in the inspection area. Thereby, abnormality of the surface of a to-be-inspected area can be detected with high accuracy.

  In the above configuration, each bright part system includes a plurality of bright parts, and the interval between the bright parts included in the same bright part system is M times the width of the bright part (M is an integer of 1 or more). ) And the distance between the light parts included in different light part systems is (N + K / L) times the width of the light part (N is 0 or an integer, K, L is an integer satisfying K <L) is there. By configuring in this manner, it is possible to obtain shooting data that is projected by shifting the bright parts of different bright part systems to the inspection area. Thereby, it is possible to detect an abnormality on the surface of the inspection area with high accuracy.

  In the above configuration, the L is the number of bright portion systems included in the projection pattern. With this configuration, it is possible to evenly shift the projection area of the bright part according to the number of bright part systems. Abnormality of the surface of the inspection area can be detected with high accuracy.

  In the above configuration, the K is a number having no positive common divisor other than 1 or the L and 1. By comprising in this way, duplication of the projection area | region of the some bright part contained in a bright part system | strain can be suppressed. This makes it possible to increase the test redundancy and the robustness.

  In the above configuration, the control unit controls the imaging timing of the imaging unit so as to capture the inspection area each time the inspection area moves P times the width of the bright portion, and the P is a bright section. It is the number of bright parts included in the lineage. By configuring in this way, it is possible to suppress overlapping of projection areas of the bright parts of different bright part systems. This makes it possible to increase the test redundancy and the robustness.

  In the above configuration, the M does not satisfy (M + 1) × (k−1) = P × n (k is a positive integer smaller than P and n is a positive integer). By configuring in this way, it is possible to suppress the overlap of the projection area of the bright part. This makes it possible to increase the test redundancy and the robustness.

  In the above configuration, the illumination unit projects a bright part irradiated with light of a different color temperature for each of the bright part systems. With this configuration, it is possible to suppress the variation in the detection accuracy of the abnormality due to the color of the inspection area, the optical characteristics of the imaging unit, and the like. This can increase the robustness of the test.

  In the above configuration, the inspection area may be moved, or the illumination unit may be moved.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the surface inspection apparatus which can test | inspect the surface of a to-be-inspected area | region accurately and in a short time.

It is the schematic which shows an example of the surface inspection apparatus concerning this invention. It is a block diagram which shows the connection of the surface inspection apparatus shown in FIG. It is sectional drawing which shows the structure of an illumination part. It is a figure which shows surface inspection by the surface inspection apparatus concerning this invention. It is a flowchart which shows the process which test | inspects the to-be-inspected area | region by a surface inspection apparatus. It is a figure which shows the illumination part used for the other example of the surface inspection apparatus concerning this invention. It is a figure which shows surface inspection in the other example of the surface inspection apparatus concerning this invention. It is a figure which shows the illumination part used for the other example of the surface inspection apparatus concerning this invention. It is a figure which shows surface inspection in the other example of the surface inspection apparatus concerning this invention. It is a figure which shows the illumination part used for the other example of the surface inspection apparatus concerning this invention. It is a figure which shows surface inspection in the other example of the surface inspection apparatus concerning this invention. It is a figure which shows the illumination part used for the other example of the surface inspection apparatus concerning this invention. It is a figure which shows the surface inspection in the other example of the surface inspection apparatus concerning this invention.

  The configuration of the present invention will be described with reference to the drawings.

First Embodiment
<Configuration of surface inspection device>
FIG. 1 is a schematic view showing an example of a surface inspection apparatus according to the present invention. FIG. 2 is a block diagram showing the connection of the surface inspection apparatus shown in FIG. As shown in FIGS. 1 and 2, the surface inspection apparatus A includes an imaging unit 10, an illumination unit 20, a control unit 30, and an image processing unit 40. The surface inspection apparatus A irradiates illumination light from the illumination unit 20 to the inspection area CP of the moving inspection object CA. Then, the surface of the inspection area CP irradiated with the illumination light is imaged by the imaging unit 10 and inspected for abnormalities on the surface of the inspection area CP such as scratches, distortions, dirt, and foreign matter based on the imaging data. Do.

<About the shooting unit 10>
The imaging unit 10 includes an imaging device such as a CMOS or a CCD. The imaging unit 10 images the inspection area CP from a direction that intersects the moving direction of the inspection object CA. The imaging unit 10 is connected to the control unit 30, and the imaging unit 10 captures an image of the inspection area CP in accordance with the imaging timing determined by the control unit 30. Then, the imaging data of the inspected region CP taken is transmitted to the control unit 30. The details of the imaging timing will be described later.

<About the lighting unit 20>
Illumination light is irradiated toward the inspection area CP of the inspection object CA moving in the movement direction D1. By irradiating the illumination light, a projection pattern PP in which bright portions B and dark portions G are alternately arranged is projected onto the inspection region CP.

  The details of the illumination unit 20 will be described with reference to the new drawings. FIG. 3 is a cross-sectional view showing the configuration of the illumination unit. As shown in FIG. 3, the illumination unit 20 includes a light source 21, a diffusion plate 22, and a mask member 23. The light source 21 is a light emission source of light irradiated on the inspection area CP. Here, a plurality of LEDs are two-dimensionally arrayed on a plane. However, the present invention is not limited to this. For example, a discharge light emitter such as a discharge tube or a planar light source such as an organic EL may be used.

  The diffusion plate 22 is an optical element that makes the intensity (for example, the luminance) of the passing light uniform or substantially uniform in the plane. The diffusion plate 22 is disposed in front of the light source 21. In addition, in the illumination part 20, the front surface shall refer to the surface by the side of the to-be-tested area | region CP of the illumination part 20. FIG. That is, the light emitted from the light source 21 passes through the diffusion plate 22. In addition, when the light from the light source 21 has a uniform intensity in the plane, the diffusion plate 22 may be omitted.

  The mask member 23 is disposed on the front surface of the diffusion plate 22. The mask member 23 is provided with a band-shaped opening window 231. Of the light emitted from the diffusion plate 22 to the front surface, the light incident on the opening window 231 passes through the opening window 231 and the rest is blocked by the mask member 23. In the illumination unit 20, a part where the light passes through the opening window 231 is referred to as an optical band 24, and a part where the light is blocked by the mask member 23 is referred to as a non-illumination band 25. In addition, in the illumination part 20 shown in FIG. 3, although there are two light bands 24, it is not limited to this, You may include many more light bands 24. FIG. Moreover, although the board member colored black can be mentioned as the mask member 23, It is not limited to this. For example, when a shutter using liquid crystal or the like is used as a mask member, the number and width of the opening windows 231, that is, the light bands 24 can be changed. As a result, it is possible to change the degree of redundancy, the degree of definition, the inspection speed, etc. described later, and the versatility of the surface inspection apparatus A becomes high.

  As shown in FIG. 3, the light band 24 has a fixed width along the moving direction D1 of the test object CA, and has a rectangular shape extending in a direction (vertical direction in FIG. 3) orthogonal to the moving direction D1. . The non-illumination band 25 is provided between the two light bands 24 and is also provided outside the two light bands 24. That is, in the illumination unit 20, the light bands 24 and the non-illumination bands 25 are alternately arranged side by side in the movement direction D1.

  In the illumination unit 20, the light source 21 is always lit. Then, the illumination light from the illumination unit 20 is irradiated to the inspection area CP, so the light band 24 is projected as the bright part B onto the inspection area CP, and the non-illumination band 25 is projected as the dark part G. That is, the projection pattern PP in which the bright portions B and the dark portions G are alternately arranged is projected onto the inspection region CP. The details of the projection pattern PP including the bright part B and the dark part G will be described later.

<About Control Unit 30>
The control unit 30 controls each part of the surface inspection apparatus A. The imaging unit 10, the illumination unit 20, and the image processing unit 40 are connected to the control unit 30. Further, the transport unit 50, the display unit 60, the storage unit 70, and the like are connected to the control unit 30. The control unit 30 is provided with an operation unit 31 for performing an operation. The arithmetic unit 31 is a circuit including arithmetic circuits such as a CPU and an MPU. The calculation unit 31 performs a calculation by operating a program incorporated in the calculation unit 31 or reading and operating a program stored in the storage unit 70. The control unit 30 sends a control signal to the photographing unit 10, the illumination unit 20, the image processing unit 40, and the like based on the calculation result by the calculation unit 31. As the control signal, for example, a signal for notifying the imaging unit 10 of imaging timing, a signal for changing the width of the non-illumination band 25 for the illumination unit 20, and the like can be mentioned, but it is not limited thereto.

  In addition, the control unit 30 inspects the presence or absence of an abnormality on the surface of the inspection area CP based on the imaging data processed by the image processing unit 40. In the photographing data, a bright part B and a dark part G are photographed, and the control unit 30 detects the presence or absence of surface abnormalities such as scratches, distortion, dirt, and foreign matter in the bright part B. In addition, when an abnormality on the surface is detected, the control unit 30 specifies a portion where the abnormality is formed in the inspection area CP. At this time, the control unit 30 combines the imaging data to generate an image of the entire inspection area CP, and further performs a display that can identify a portion having an abnormality in the inspection area CP. Then, the image data and the information on the place where the abnormality has occurred are associated with each other and stored in the storage unit 70, and the display unit 60 displays the abnormal part of the inspection region CP.

<About Image Processing Unit 40>
The image processing unit 40 is connected to the imaging unit 10. The image processing unit 40 receives shooting data shot by the shooting unit 10 and performs image processing necessary for detecting an abnormality on the shooting data. Then, the image processing unit 40 sends the photographed data after processing to the control unit 30. Note that image processing is known processing in surface inspection, such as binarization processing and differentiation processing, and details thereof are omitted. Further, the shooting data shot by the shooting unit 10 may be sent directly to the image processing unit 40, or temporarily stored in the storage unit 70 and then sent to the image processing unit 40. Good. In the case of a configuration for sending to the storage unit 70, the pre-processing shooting data and the post-processing shooting data may be associated with each other and stored in the database. By doing in this way, it is also possible to perform image processing different from the image processing performed by the image processing unit 40.

  In the surface inspection apparatus A according to the present invention, the control unit 30 and the image processing unit 40 are separate components (for example, circuits). However, the processing unit is a combination of the control unit 30 and the image processing unit 40 It is good. For example, the control unit and the image processing unit may be configured by a program that operates on an arithmetic circuit provided in the processing device.

<About other configurations>
The transport unit 50 transports the inspection object CA. The inspection object CA is transported so that the inspection region CP crosses the imaging range of the imaging unit 10. The transport unit 50 is connected to the control unit 30, and the transport unit 50 notifies the control unit 30 of the moving speed of the test object CA being transported. The control unit 30 may obtain the moving speed and the position of the inspection area CP from a sensor (not shown) that detects the position of the inspection area CP instead of the transport unit 50. Further, the moving speed and the position from the sensor may be acquired from the transport unit 50, or the moving speed and the position accuracy may be complemented to each other while acquiring the moving speed and the position information from both, and the moving speed and the position accuracy of the inspection area CP may be complemented. It may be enhanced.

  The display unit 60 includes, for example, a display panel such as a liquid crystal panel. The display unit 60 is connected to the control unit 30, and the display unit 60 displays information such as shooting data shot by the shooting unit 10, shooting data after processing by the image processing unit 40, and the state of a projection pattern To do. The display unit 60 can also display an alarm to warn an operator that there is an abnormality when the control unit 30 detects an abnormality in the inspection area CP. Note that a touch panel may be attached to the display unit 60. With the touch panel attached, the operator can operate the surface inspection apparatus A, input information, and the like using the touch panel. In addition, hard keys such as numeric keys may be provided. In addition to these, a voice notification unit (not shown) that performs notification by voice may be provided.

  The surface inspection apparatus A concerning this invention is equipped with the structure shown above. Next, the operation of the surface inspection apparatus A according to the present invention will be described.

<About surface inspection>
FIG. 4 is a view showing surface inspection by the surface inspection apparatus according to the present invention. In FIG. 4, the uppermost row shows a projection pattern PP1 projected onto the inspection area CP. A projection pattern PP1 projected on the moving inspection area CP is shown below the projection pattern PP1. Furthermore, the lowermost row shows an inspection area CP which is covered by imaging data captured by the imaging unit 10, in other words, a plurality of imaging data combined.

  As shown in FIG. 4, the projection pattern PP1 projected onto the inspection area CP is a pattern in which bright portions and dark portions are alternately arranged along the moving direction of the inspection area CP. The projection pattern PP1 of the present embodiment is referred to as a first projection pattern PP1. The first projection pattern PP1 includes a first bright part system BR1 and a second bright part system BR2 which are irradiated with being shifted to the inspection area CP. In the first projection pattern PP1, the first bright part system BR1 includes one bright part B1, and the second bright part system BR2 includes one bright part B2. In FIG. 4, the bright part B1 is hatched with diagonal lines in the upper left, and the bright part B2 is hatched with diagonal lines in the upper right. In the first projection pattern PP1, the width W1 of the moving direction D1 of the bright part B1 of the first bright part system BR1 and the width W1 of the moving direction D1 of the bright part B2 of the second bright part system BR2 have the same width. .

  In the first projection pattern PP1, the first bright part system BR1 is arranged upstream of the second bright part system BR2 in the direction in which the inspection region CP moves. A dark part G1 is provided between the bright part B1 of the first bright part system BR1 and the bright part B2 of the second bright part system BR2. Further, in the first projection pattern PP1, a dark portion G0 is provided outside the light portion B1 of the first light portion system BR1 and the light portion B2 of the second light portion system BR2. The dark part G0 is a shadow of the non-illumination band 25 in the illumination unit 20. Therefore, as long as the illumination unit 20 can accurately project the bright portions B1 and B2 onto the inspection area CP, the outer dark portion G0 may be omitted.

  When the inspection region CP passes in front of the imaging unit 10 and the illumination unit 20, the bright portion B1 of the first bright portion system BR1 is projected onto the inspection region CP. Then, by further moving the inspection area CP, the bright part B2 of the second bright part system BR2 is also projected onto the inspection area CP.

  In the surface inspection apparatus A, the image data captured by the image capturing unit 10 is subjected to image processing by the image processing unit 40, and then subjected to arithmetic processing by the control unit 30 to obtain portions corresponding to the bright portions B1 and B2 of the processed image data. Detect existing anomalies. That is, the surface inspection apparatus A detects an abnormality in a portion where the bright portions B1 and B2 of the imaging data are projected.

  In the surface inspection apparatus A, imaging is performed a plurality of times while the inspection area CP moves in front of the imaging unit 10 and the illumination unit 20. The control unit 30 operates the imaging unit 10 by adjusting the timing of imaging so that the bright area B1 becomes imaging data projected without a gap on the inspection area CP by combining the respective imaging data. . Further, when the first projection pattern PP1 is photographed at the same photographing timing, similarly, it is possible to obtain photographed data in which the bright part B2 of the second bright part system BR2 is projected on the inspection area CP without a gap. Configured.

  Although details will be described later, in the surface inspection apparatus A, the boundary of the bright part B1 of the first bright part system BR1 and the border of the light part B2 of the second bright part system BR2 when the respective photographing data are combined. The configuration and the imaging timing of the first projection pattern PP1 are determined so as to be shifted.

The configuration of the first projection pattern PP1 will be described. In the abnormality detection by the surface inspection apparatus A, it is easy to detect an abnormality present in the central portion of the portion on which the bright portions B1 and B2 are projected due to the characteristics of the abnormality detection method. Furthermore, in the surface inspection apparatus A, depending on the accuracy of the imaging unit 10, when the widths of the bright parts B1 and B2 are narrow and the brightness difference between the bright part and the dark part is large, that is, the bright parts B1 and B2 When the width is narrow and the bright portions B1 and B2 are sufficiently brighter than the dark portions G0 and G1, the abnormality detection accuracy becomes high. In consideration of these matters, in the surface inspection apparatus A, the width W1 of the bright part and the width W2 of the dark part are set as shown in the following formula 1.

  As shown in FIG. 4, L is the number of bright part systems, and in the surface inspection apparatus A, L = 2. And since K is a positive integer less than L, K = 1. Furthermore, N is 0 or a positive integer. For example, if N = 0, then W2 = (W1) / 2. When the light part B1 and the light part B2 approach and the dark part G1 becomes too narrow, the dark part G1 becomes bright under the influence of the light from the light part B1 and the light part B2, that is, the light band 24 In some cases, the difference in brightness between the image and the dark area may be insufficient. Therefore, it is preferable that the distance between the light portion B1 and the light portion B2, that is, the width W2 of the dark portion be a certain length or more. In addition, although it changes with the characteristics of the light source 21, the diffusion plate 22, and the mask member 23 of the illumination part 20, the minimum width of width W2 of a dark part is preset. In the surface inspection apparatus A, the minimum width of the dark part width W2 is set to be larger than ½ times the bright part width W1. Hereinafter, the same applies to each embodiment.

  Also, if the width W2 of the dark part is too wide, the length of the first projection pattern PP1 becomes long, and the moving distance of the inspection area CP from the start to the end of the inspection of the inspection area CP increases, and from the inspection start to the end The number of shots taken by the shooting unit 10 increases, and the amount of image processing increases. As the moving distance becomes longer and the number of image data to be imaged increases, the inspection processing time becomes longer and work efficiency is lowered. Therefore, in the surface inspection apparatus A, it is preferable that the width W2 of the dark part G1 is small while maintaining the brightness difference between the dark part G1, the bright part B1, and the bright part B2. For this reason, in this embodiment, N = 1. As a result, the width W2 of the dark part was 1.5 (3/2) times the width W1 of the bright part.

<About surface inspection operation>
In the surface inspection apparatus A, the first projection pattern PP1 is projected onto the moving inspection area CP, and photographing is performed by the photographing unit 10 at a predetermined photographing timing. Then, the photographic data is subjected to image processing by the image processing unit 40, and the control unit 30 detects an abnormality from the photographic data subjected to image processing. Here, the surface inspection operation will be described.

  As shown in FIG. 4, in order to facilitate the understanding of the operation of the surface inspection of the inspection region CP by the surface inspection apparatus A, the inspection region CP is considered in division. First, the inspection area CP is divided into every width W1. As a result, the inspection area CP is divided into 12 areas. Then, the inspection area CP moves from left to right in FIG. 4 and assigns numbers 1 to 12 sequentially from left to right to each of the divided areas. The 12-divided part is further divided into 2 and the code of _a or _b is given to each of the divided parts. For example, the left end of the inspection area CP is referred to as an area 1_a and an area 1_b from the left. And the right side is made into area 2_a, area 2_b, and area 3_a in order. And let the right end part side of to-be-inspected area | region CP be the area | region 12_a and area | region 12_b from the left.

  The inspection operation of the inspection area CP by the surface inspection apparatus A will be described with reference to a new drawing. FIG. 5 is a flowchart showing a process of inspecting the inspection area by the surface inspection apparatus. As shown in FIG. 5, the control unit 30 acquires the moving speed and the position of the inspection area CP based on the information from the conveyance unit 50 (step S101).

  The control unit 30 confirms whether or not imaging at the first imaging timing has been executed in the inspection (step S102). The control unit 30 does not perform imaging at the first imaging timing (in the case of No in step S102), the control unit 30 sets the front end (here, the area 12_b) in the movement direction D1 of the inspection area CP to the projection range of the bright portion B1. (Step S103). If the front end of the inspection area CP is not within the projection range of the bright part B1 (No in step S103), the control unit 30 determines that the first imaging timing has not been reached, and the movement speed of the inspection area CP And return to the acquisition of the position (step S101).

  When it is detected that the front end (region 12_b) in the movement direction D1 of the inspection region CP has entered the portion where the bright portion B1 is projected (in the case of Yes in step S103), the control unit 30 Then, an instruction is sent to the photographing unit 10 to perform the first photographing (step S105). In the surface inspection apparatus A, as shown in FIG. 4, the timing at which the bright portion B1 is projected over the entire region 12_b is set as the first imaging timing. Although the details will be described later, the timing may be deviated from the timing when the bright part B1 is projected on the entire area 12_b, but the control unit 30 projects the bright part B1 on at least a part of the area 12_b. The timing is determined as the first shooting timing.

  The surface inspection apparatus A acquires imaging data obtained by projecting and projecting the bright part B1 and the bright part B2 in the inspection area CP without gaps in multiple times of imaging, and detects an abnormality. Therefore, after photographing is performed at the first photographing timing, the control unit 30 sets the photographing timing every time the inspection area CP moves by the width W1 of the bright portion B1 and the bright portion B2, and the photographing portion 10 is set. Get the shooting data shot with. Therefore, when imaging at the first imaging timing of the inspection area CP has been performed (Yes in step S102), the control unit 30 moves the inspection area CP by the width W1 of the bright area from the previous imaging timing. Whether or not (step S104). When the width W1 of the bright portion B1 (B2) is not moved (No in step S104), the control unit 30 resumes acquisition of the moving speed and position of the inspection area CP from the transport unit 50 (in step S101). Return).

  When the inspection area CP moves the width W1 of the bright part B1 (B2) (in the case of Yes in step S104), the control unit 30 sends an instruction to the imaging unit 10 as the next imaging timing comes, and the imaging unit 10 The imaging of the inspection area CP is performed (step S105). Then, the imaging unit 10 transmits the captured imaging data to the image processing unit 40 (step S106). Note that transmission of shooting data to the image processing unit 40 by the shooting unit 10 may be performed automatically after completion of shooting, or may be performed based on an instruction from the control unit 30.

  The image processing unit 40 performs image processing on the sent image data (step S107). As described above, in the image data subjected to the image processing, the image processing is performed such that it becomes easy to detect an abnormality provided in a portion on which the bright part B1 and / or B2 of the inspection area CP is projected. Then, the image data subjected to the image processing is sent to the control unit 30. Then, the control unit 30 refers to the image data subjected to the image processing to detect an abnormality in a portion on which the bright part B1 and / or B2 of the inspection area CP is projected (step S108). In addition, although it is set as abnormality detection in step S108 in this embodiment, the detection about the presence or absence of abnormality is also included here. Note that the image processing by the image processing unit 40 and the abnormality detection by the control unit 30 may be performed sequentially after the image processing or may be performed in parallel.

  The control unit 30 associates the original imaging data with the imaging data after the image processing and records them in the storage unit 70 (step S109). If an abnormality is detected, information about the abnormality (position in the inspected region CP, for example, the region number, the type of abnormality, for example, scratches, deformation, adhesion of foreign matter, etc.) It is stored together with the later shooting data. The recording of the information in the storage unit 70 may be performed only when an abnormality is found. In the surface inspection apparatus A, when the rear end of the inspection area CP passes through the bright portion B2, the inspection of the inspection area CP ends. Therefore, the control unit 30 confirms whether the rear end of the inspection area CP has passed through the bright part B2 (step S110).

  If the rear end of the inspection area CP does not pass through the bright part B2 (No in step S110), the control section 30 moves from the transport section 50 on the assumption that the inspection of the entire inspection area CP has not been completed. Acquisition of speed and position information is resumed (return to step S101).

  When the rear end of the inspected area CP passes through the bright part B2 (in the case of Yes in step S110), the control unit 30 accesses the storage unit 70 to check whether there is no abnormality in the inspected area CP that has been inspected. It is confirmed whether or not (step S111). If there is no abnormality (Yes in step S111), the control unit 30 displays an image of the inspected area CP and information indicating that there is no abnormality (for example, “no abnormality” written in characters, etc.). It outputs to the part 60 (step S112). If there is an abnormality (No in step S111), the control unit 30 outputs an image of the inspection area CP, an image indicating an abnormal part, and information indicating that there is an abnormality to the display unit 60 ( Step S113). In the case where there is an abnormality, it is possible to display an indication that there is an abnormality at the time of detecting the abnormality. Furthermore, when there is an abnormality, the abnormality may be notified by sound or light.

  In the surface inspection apparatus A, the bright part B1 and / or the bright part B2 is projected onto the moving inspection area CP, and imaging is performed every time the inspection area CP moves the width W1 of the bright area, so that FIG. As shown, the portions on which the bright part B1 and / or the bright part B2 in the shooting data are projected move in order. As a result, in the surface inspection apparatus A, the bright part B1 is sequentially projected onto different parts of the inspection region CP, and photographing is performed in a state where the bright part B1 is projected onto different parts. Similarly, the bright part B2 is projected onto different portions of the inspection area CP, and photographing is performed with the bright part B2 projected onto different parts.

  The mask member 23 is formed so that the illumination unit 20 is 1.5 times the width W1 of the bright portions B1 and B2 between the bright portions B1 and B2. Therefore, when the bright portion B1 is projected to 9_b and 10_a in the inspection area CP, the bright portion B2 is projected to 12_a and 12_b (see FIG. 4). That is, as shown in FIG. 4, the bright part B1 is projected onto the region r_b and the region (r + 1) _a (r is an integer) of the inspection region CP. The bright part B2 is projected onto the area s_a and the area s_b (s is an integer) of the area CP to be inspected.

  For these reasons, in the surface inspection apparatus A, the bright areas B1 and B2 that are substantially different from each other by the inspection by imaging when the inspection area CP passes in front of the imaging section 10 and the illuminating section 20. The inspection is performed by projecting the entire area of the CP. That is, two inspections are substantially possible in one inspection. In addition, that the inspection is performed twice in the surface inspection apparatus in this way is indicated as redundancy 2. The higher the degree of redundancy, the greater the number of inspections and the same agreement, which can suppress inspection omissions, that is, increase the robustness.

  In the case of inspecting the surface of the inspection area CP by irradiating a projection pattern in which light portions and dark portions are alternately arranged, as the difference in brightness between the light portions and the dark portions is larger, the detection accuracy of abnormality is improved. Is possible. Therefore, it is possible to detect an abnormality with higher accuracy near the center of the bright part than in the vicinity of the edge of the bright part. Further, as shown in FIG. 4, the width W2 of the dark area G1 between the bright area B1 and the bright area B2 is 1.5 times the width W1 of the bright area, and the inspection area CP moves the width W1 of the bright area Each time the control is performed, the portion where the bright portion B1 is projected and the portion where the bright portion B2 is projected are shifted by half the width W1 of the bright portion.

  Thus, the central portion of the bright portion B1 becomes an edge portion of the bright portion B2, and the central portion of the bright portion B2 becomes an edge portion of the bright portion B1. As described above, since the accuracy of abnormality detection is high at the central part of the bright part and low at the edge part, it is difficult for the bright part B1 and the bright part B2 to be deviated to detect the abnormality in the other bright part projection. It is possible to compensate for the anomaly detection of a part. From this, according to the surface inspection apparatus A, not only redundancy 2 but in each bright part, it becomes possible to detect an abnormality in a portion that is difficult to detect, so the detection accuracy of the abnormality in the inspection area CP Can be high. That is, the inspection is performed with the same accuracy as when the inspection is performed using the projection pattern having the bright portion having a width half the width W1 of the bright portion. Assuming that this accuracy is defined as fineness, and the surface inspection apparatus A projects one bright portion and inspects it as redundancy 1, when the definition is 1, it is approximately twice as high, that is, 2 Yes.

Second Embodiment
Another example of the surface inspection apparatus according to the present invention will be described with reference to the drawings. FIG. 6 is a figure which shows the illumination part used for the other example of the surface inspection apparatus concerning this invention. FIG. 7 is a view showing surface inspection in another example of the surface inspection apparatus according to the present invention. As shown in FIG. 6, the illumination unit 20 of the surface inspection apparatus A1 according to the present embodiment differs from the illumination unit 20 of the surface inspection apparatus A in that the number of opening windows 231 of the mask member 23a is three. The other parts are the same as in the first embodiment, and substantially the same parts will be denoted by the same reference numerals, and detailed descriptions of the same parts will be omitted.

  As shown in FIG. 7, in the surface inspection apparatus A1, the second projection pattern PP2 is projected onto the inspection region CP. The second projection pattern PP2 includes a first bright part system BR1, a second bright part system BR2, and a third bright part system BR3. The first bright section system BR1 is provided with one bright section B1, the second bright section system BR2 is provided with one bright section B2, and the third bright section system BR3 is provided with one bright section B3. The third projection pattern PP3 includes a dark part G1 disposed between the bright part B1 and the bright part B2 and between the bright part B2 and the bright part B3. And dark part G0 is distribute | arranged to the outer side of bright part B1, and the outer side of bright part B3. The bright portions B1, B2, and B3 each have the same width W1, and the dark portions G1 also have the same width W2. In FIG. 7, the third light part B3 is hatched in which oblique lines crossing each other are arranged.

  The width W1 of the bright portion and the width W2 of the dark portion in the second projection pattern PP2 will be described in detail. Also in the second projection pattern PP2 of the surface inspection apparatus A1 according to the present embodiment, the bright portion width W1 and the dark portion width W2 are determined based on Equation (1). As shown in FIG. 7, in the surface inspection apparatus A1, L = 3. At this time, since the value of K is a positive integer smaller than L, K = 1, 2 can be set. Here, the value of K will be described in more detail.

  As described above, since the width W2 of the dark part is larger than half the width W1 of the bright part, K = 2 and N = 0. From this, in the second projection pattern PP2 of the surface inspection apparatus A1, the width of the dark portion is W2 = (2/3) W1 according to Equation 1.

  As the inspection area CP moves from left to right in FIG. 7, it is equally divided into 12 as in the first embodiment. Then, numbers 1 to 12 are sequentially assigned to each of the divided areas of the inspection area CP from left to right. And the part divided into 12 is further divided into three equally, and the code of _a, _b or _c is given to each divided part. For example, 1_a, 1_b, and 1_c are arranged at the left end from the left. Then, on the right side, it continues as 2_a, 2_b, 2_c, 3_a. And 12_a, 12_b, and 12_c are arrange | positioned from the left on the right end part side.

  In the surface inspection apparatus A1, when the front end in the movement direction D1 of the inspection area CP, that is, 12_c is in the bright part B1, the control unit 30 operates the imaging unit 10 as the first imaging timing to perform the first imaging Get the data. Then, each time the inspection area CP moves the width W1 of the bright part, the control unit 30 performs imaging as imaging timing. And the control part 30 complete | finishes an inspection, when the rear end of the moving direction of to-be-inspected area | region CP passes the bright part B3.

  By shooting in this way, the bright portion B1 is projected onto the region r_c, the region (r + 1) _a, and the region (r + 1) _b (r is an integer). The bright part B2 is projected onto the region s_b, the region s_c, and the region (s + 1) _a (s is an integer). The bright part B3 is projected onto the area t_a, the area t_b and the area t_c (t is an integer). The projected portions of the bright portions B1, B2 and B3 of the inspection area CP in the photographing data are shifted by 1/3 of the width W1 of the bright portions. Thus, in the surface inspection apparatus A1, the inspection can be performed with the redundancy 3 and the definition 3. The inspection apparatus A1 can inspect with higher definition and can further enhance the robustness.

  Other features are the same as those of the first embodiment.

Third Embodiment
Another example of the surface inspection apparatus according to the present invention will be described with reference to the drawings. FIG. 8 is a view showing an illumination unit used in another example of the surface inspection apparatus according to the present invention. FIG. 9 is a view showing surface inspection in another example of the surface inspection apparatus according to the present invention. As shown in FIG. 8, the illumination unit 20 of the surface inspection apparatus A2 according to the present embodiment is different from the illumination unit 20 of the surface inspection apparatus A in that the number of the opening windows 231 of the mask member 23b is four. The other parts are the same as in the first embodiment, and substantially the same parts will be denoted by the same reference numerals, and detailed descriptions of the same parts will be omitted.

  As shown in FIG. 9, in the surface inspection apparatus A2, a third projection pattern PP3 is projected onto the inspection region CP. The third projection pattern PP3 includes a first bright section system BR1, a second bright section system BR2, a third bright section system BR3 and a fourth bright section system BR4. The first bright part system BR1 has one bright part B1, the second bright part system BR2 has one bright part B2, and the third bright part system BR3 has one bright part B3 and the fourth bright part system BR4. Each has one bright part B4. The third projection pattern PP3 includes a dark portion G1 disposed between the light portion B1 and the light portion B2, between the light portion B2 and the light portion B3, and between the light portion B3 and the light portion B4. And dark part G0 is distribute | arranged to the outer side of bright part B1, and the outer side of bright part B4. The bright portions B1, B2, B3 and B4 each have the same width W1, and the dark portion G1 also has the same width W2. In FIG. 9, the fourth bright portion B4 is hatched with horizontal lines.

  The width W1 of the bright portion and the width W2 of the dark portion in the third projection pattern PP3 will be described in detail. Also in the third projection pattern PP3 of the surface inspection apparatus A2 according to the present embodiment, the width W1 of the bright part and the width W2 of the dark part are determined based on Equation 1. As shown in FIG. 9, L = 4 in the surface inspection apparatus A2. At this time, since the value of K is a positive integer smaller than L, K = 1, 2, 3 can be set. Here, the value of K will be described in more detail.

  For example, when L = 4 and K = 2, K / L of Equation 1 is 2/4 = 1/2. When the third projection pattern PP3 of this configuration is projected onto the inspection area CP for inspection, in each photographing data, the adjacent bright portions B1, B2, B3 and B4 are 1/2 times the width W1 of the bright portions. Projected out of position. In other words, the projection areas of the bright part B1 and the bright part B2 are shifted by a half of the width W1 of the bright part. The projection area of the bright part B1 and the bright part B3 is shifted by 1 times the width W1 of the bright part, and the bright part B1 and the bright part B3 substantially overlap each other. Similarly, the projection areas of the bright portion B2 and the bright portion B4 substantially overlap. Therefore, when L = 4 and L = 2, redundancy 4 is obtained, but definition 2 is obtained.

  On the other hand, when K = 1 or 3, adjacent bright portions B1, B2, B3, and B4 are projected with a shift of 1/4 times or 3/4 times the width W1 of the bright portion. The areas onto which B1, B2, B3, and B4 are projected do not substantially overlap completely, and at least a part thereof is shifted. Therefore, when K = 1 or 3, redundancy 4 and definition 4 can be obtained. When K = 1, K / L = 1/4, which is smaller than 1/2. Therefore, in Equation 1, it is necessary to set N = 1, and W2 = (5/4) W1. On the other hand, in the case of K = 3, K / L = 3/4, which is larger than 1/2. Therefore, in Equation 1, N can be 0, and W2 = (3/4) W3. In order to keep the width of the third projection pattern PP3 small, here, L = 4, L = 3, N = 0, and according to Equation 1, the width W2 of the dark portion is 3/4 times the width W1 of the bright portion. .

  The inspection area CP is equally divided into 12 as in the first embodiment, as it moves from left to right in FIG. Then, numbers 1 to 12 are sequentially assigned to each of the divided areas of the inspection area CP from left to right. Then, the 12 divided parts are further divided into four equal parts, and the code of _a, _b, _c or _d is given to each of the divided parts. For example, 1_a, 1_b, 1_c, 1_d are arranged at the left end from the left. Then, 2_a, 2_b, 2_c, 2_d, and 3_a are continued on the right side. And 12_a, 12_b, 12_c, 12_d are arrange | positioned from the left at the right end side.

  In the surface inspection apparatus A2, when the front end of the movement direction D1 of the inspection area CP, that is, 12_d is in the bright part B1, the control unit 30 operates the imaging unit 10 as the first imaging timing to perform the first imaging Get the data. Then, each time the inspection area CP moves the width W1 of the bright part, the control unit 30 performs imaging as imaging timing. And the control part 30 complete | finishes an inspection, when the rear end of the moving direction of to-be-inspected area | region CP passes the bright part B4.

  By performing imaging in this manner, the bright part B1 is projected onto the area r_d, the area (r + 1) _a, the area (r + 1) _b, and the area (r + 1) _c (r is an integer). The bright portion B2 is projected onto the region s_c, the region s_d, the region (s + 1) _a, and the region (s + 1) _b (s is an integer). The bright part B3 is projected onto the area t_b, the area t_c, the area t_d and the area (t + 1) _a (t is an integer). The bright part B4 is projected onto the area u_a, the area u_b, the area u_c, and the area u_d (u is an integer). The portions where the bright portions B1, B2, B3, and B4 of the inspection area CP in the imaging data are projected are shifted by 1/4 of the width W1 of the bright portion. Thus, in the surface inspection apparatus A2, the inspection can be performed with the redundancy 4 and the definition 4. In the surface inspection apparatus A2, it is possible to inspect with higher definition than when the redundancy is 3. That is, it is possible to further enhance the robustness.

  Summarizing the above, in the surface inspection apparatus A2, K is a positive integer smaller than 1 or L and is a number having no positive common divisor other than L and 1 and an array of the bright part and the dark part of the projection pattern To decide. Then, by using the illumination capable of projecting the determined projection pattern onto the inspection area CP, the surface inspection apparatus A2 can perform surface inspection with a high degree of redundancy and definition.

  In the surface inspection apparatus A2, when an inspection with high redundancy and definition is desired, a positive integer smaller than 1 or L as K and a number without positive common divisors other than L and 1 (the above In the example, it is set to 1, 3). Also, if it is desired to increase the redundancy but the definition may be somewhat lower, K may be set to a positive integer smaller than L (2 in the above example). In the present embodiment, K has been described by taking L = 4 as an example. However, the selection of K is the same even when L = 4. That is, K is a positive integer at least smaller than L, preferably 1 or a positive integer having no positive common divisor other than 1 and L.

  Other features are the same as those of the first embodiment.

Fourth Embodiment
Another example of the surface inspection apparatus according to the present invention will be described with reference to the drawings. FIG. 10 is a view showing an illumination unit used in another example of the surface inspection apparatus according to the present invention. FIG. 11 is a view showing surface inspection in another example of the surface inspection apparatus according to the present invention. As shown in FIG. 10, the illumination unit 20 of the surface inspection apparatus A3 according to the present embodiment differs from the illumination unit 20 of the surface inspection apparatus A in that the number of opening windows 231 of the mask member 23c is six. The other parts are the same as those in the first embodiment, and substantially the same parts are denoted by the same reference numerals and detailed description of the same parts is omitted.

  As shown in FIG. 11, in the surface inspection apparatus A3, a fourth projection pattern PP4 is projected onto the inspection region CP. The fourth projection pattern PP4 includes a first bright portion system BR1 disposed on the most upstream side in the movement direction D1 of the inspection region CP, and a second bright portion system BR2 disposed next to the first bright portion system BR1. The first bright section system BR1 is a first bright section B11, the second bright section B12 and the third bright section B13, and the second bright section system BR2 is a first bright section B21, a second bright section B22 and a third bright section B21. Part B23 is provided. Each bright portion of the first bright portion system BR1 is hatched with diagonal lines rising to the left. In addition, the hatching of the 1st bright part B11, the 2nd bright part B12, and the 3rd bright part B13 differs in the width | variety of an oblique line. Further, each bright portion of the second bright portion system BR2 is hatched with diagonal lines rising to the right. In addition, the hatching of the 1st bright part B21, the 2nd bright part B22, and the 3rd bright part B23 differs in the width | variety of an oblique line.

  In the fourth projection pattern PP4, a dark part G1 having a dark part width W21 is arranged between the first bright part system BR1 and the second bright part system BR2. In addition, dark portions G2 having the same width W22 of the dark portions are disposed between the light portions of the first light portion system BR1 and between the light portions of the second light portion system BR2.

  Here, focusing on the first bright portion system BR1, the first bright portion B11, the second bright portion B12, and the third bright portion B13 alternate with no gaps in the inspection area CP by combining a plurality of shooting data. Projected. The same applies to the second bright part system BR2.

  Then, in the fourth projection pattern PP4, there are two bright part systems, and the projection area of the bright part of each bright part system is such that the width W21 of the dark part G1 and the dark part G2 are shifted by 1/2 of the width of the bright part. Width W22 is set. The widths W21 and W22 of the dark portion will be described below.

  The width W21 of the dark part is the width of the dark part G1 of the part sandwiched between the bright parts of different bright part systems. Therefore, the dark portion width W21 is determined based on Equation 1. That is, in the fourth projection pattern PP4, L = 2, L = 2, and N = 1. The width W21 of the dark portion is W21 = (3/2) × W1 according to Equation 1.

  Also, the dark portion width W22 is determined in order to spread the projection region of the bright portion of one bright portion system on the inspection region CP. For example, in the first bright part system BR1, the area where the first bright part B11 is projected, the area where the second bright part B12 is projected, and the area where the third bright part B13 is projected do not overlap. In the surface inspection apparatus A3, the imaging timing is determined by the number of bright portions included in the bright portion system. Assuming that the number of bright parts included in the bright part system is P, the imaging timing is reached every time the inspected region CP moves P times the width W1 of the bright part. In the surface inspection apparatus A3, P = 3, that is, every time the inspection area CP moves three times the width W1 of the bright portion, the imaging timing is reached.

  The first bright area B11, the second bright area B12, and the third bright area B13 are sequentially projected on the inspection area CP when the photographing timing is reached every three times the width W1 of the bright area of the inspection area CP. Make it Therefore, in the fourth projection pattern PP4, the area of the dark part G2 is not overlapped so that the area where the first bright part B11 is projected, the area B12 where the second bright part B12 is projected, and the area where the third area B13 is projected do not overlap. The width W22 is determined.

The width W22 of the dark portion G2 is determined by the number of bright portions included in the bright portion system. The width W22 of the dark portion G2 is M times the width W1 of the bright portion. The first imaging timing is assumed to be when the most upstream bright portion is projected on the front end of the inspection area CP. The area of the front end portion of the inspection area CP has moved by P × W1 × n from the first imaging timing at the projection timing of n + 1 times. At this time, if the most distal region overlaps the bright portion, the bright portion cannot be projected onto the inspection region without a gap. If the bright part at that time is the k-th bright part counting from the first bright part, the length from the first bright part to the k-th bright part is (k-1) bright parts, and Since there are (k−1) dark portions G2, (k−1) × W1 + M × (k−1) × W1 = (M + 1) × (k−1) × W1. When these become equal, it becomes impossible to project without gaps. The equation representing this is Equation 2.

  By setting M and P so that Equation 2 is not satisfied, it is possible to project a plurality of bright portions onto the region to be inspected without gaps.

  Here, the number of bright parts included in the bright part system is P = 3, and when k = 2, M = 3n−1, and when k = 3 2M = 3n−2, when n is changed A positive integer that does not satisfy these equations can be M. Then, in order to make the width of the fourth projection pattern PP4 as small as possible, M = 1. That is, W22 = W1.

  That is, in the fourth projection pattern PP4, the width W22 of the dark portion G2 is the same as the width W1 of the bright portion. This relationship also holds for the second bright part system BR2.

  The inspection area CP is equally divided into 12 as in the first embodiment as it moves from left to right in FIG. Then, numbers 1 to 12 are sequentially assigned to each of the divided areas of the inspection area CP from left to right. Then, the divided part is further divided into two equal parts, and the code of _a or _b is given to each divided part. For example, 1_a and 1_b from the left are arranged at the left end. Then, 2_a, 2_b, and 3_a are continued on the right side. And 12_a and 12_b are arranged from the left on the right end side.

  In the surface inspection apparatus A3, when the front end of the movement direction D1 of the inspection area CP, that is, 12_b is in the first bright part B11 of the first bright part system BR1, the control unit 30 captures an image as the first imaging timing. The first photographing data is acquired by operating the unit 10. Then, the control unit 30 performs imaging as the imaging timing every time the inspection area CP moves three times the width W1 of the bright part. And the control part 30 complete | finishes a test | inspection, when the rear end of the moving direction of to-be-inspected area | region CP passes 3rd bright part B23 of 2nd bright part system | strain BR2.

  By performing imaging in this way, the first bright part B11 of the first bright part system BR1 is the area 3r_b, the area (3r + 1) _b (r is a positive integer), and the second bright part B12 is the area (3s- 1) _b, region 3s_a (s is a positive integer), and the third bright part B13 are projected onto region (3t-2) _b and region (3t-1) _a (t is a positive integer), respectively. The first bright part B21 of the second bright part system BR2 is a region (3u-2) _a, a region (3u-2) _b (u is a positive integer), and the second bright part B22 is a region (3v). The area _a, the area (3v) _b (v is a positive integer), and the third bright part B33 are projected to the area (3w-1) _a and the area (3w-1) _b (w is a positive integer), respectively. The projected portions of the bright portions of the bright portion systems BR1 and BR2 of the inspection area CP in the photographic data are shifted by 1/2 of the width W1 of the bright portions. As described above, in the surface inspection apparatus A3, the inspection can be performed with the degree of redundancy 2 and the definition 2 as well.

  Then, in the surface inspection apparatus A3, the imaging timing is obtained each time the inspection area CP moves three times the width W1 of the bright part, so when the imaging unit 10 has sufficient performance, the moving speed of the inspection area CP Can be tripled. Therefore, the time required for the inspection can be reduced to about 1/3. Further, even if the movement speed of the inspection area CP is the same as the case where the imaging timing is set each time the width W1 of the bright portion moves, the number of imaging timings is reduced, so the number of image processing and abnormality inspections is reduced. Thus, the time required for the inspection can be reduced, and the burden on the control unit 30, the image processing unit 40, the storage unit 70, and the like can be reduced. That is, the time and processing required for the inspection can be reduced, and the robustness can be further improved.

  Other features are the same as those of the first embodiment.

Fifth Embodiment
Another example of the surface inspection apparatus according to the present invention will be described with reference to the drawings. FIG. 12 is a figure which shows the illumination part used for the other example of the surface inspection apparatus concerning this invention. FIG. 13 is a view showing surface inspection in another example of the surface inspection apparatus according to the present invention. As shown in FIG. 12, the illumination unit 20 of the surface inspection apparatus A3 according to this embodiment is different from the illumination unit 20 of the surface inspection apparatus A in that the number of opening windows 231 of the mask member 23d is six. The other parts are the same as in the first embodiment, and substantially the same parts will be denoted by the same reference numerals, and detailed descriptions of the same parts will be omitted.

  As shown in FIG. 13, the surface inspection apparatus A4 projects the fifth projection pattern PP5 onto the inspection area CP. The fifth projection pattern PP5 includes a first bright part system BR1, a second bright part system BR2, and a third bright part system BR3 in the moving direction D1 of the inspection area CP. The first bright part system BR1 is the first bright part B11 and the second bright part B12, the second bright part system BR2 is the first bright part B21 and the second bright part B22, and the third bright part system BR3 is the first bright part. Part B31 and second bright part B32 are provided. Each bright portion of the first bright portion system BR1 is hatched with diagonal lines rising to the left. The hatchings of the first light portion B11 and the second light portion B12 have different hatching widths. Each bright portion of the second bright portion system BR2 is hatched with diagonal lines rising to the right. The hatching of the first light portion B21 and the second light portion B22 is different in the width of the oblique lines. Each bright portion of the third bright portion system BR3 is hatched by arranging intersecting oblique lines. The hatchings of the first light portion B31 and the second light portion B32 have different hatching widths.

  As shown in FIG. 13, in the fifth projection pattern PP5, the first bright portions B11, B21, and B31 are arranged in order in the moving direction of the inspection region CP. Further, on the downstream side of the first bright portion B31, second bright portions B12, B22, and B32 are arranged in order in the moving direction of the inspection region CP. That is, in the fifth projection pattern PP5, the first bright sections B11, B21 and B31 of the first bright section system BR1, the second bright section system BR2 and the third bright section system BR3 are arranged in order. Then, on the downstream side of the first light part B31 of the third light part system BR3, the second light parts B12, B22, and B32 of the first light part system BR1, the second light part system BR2, and the third light part system BR3, respectively. Arrange in order.

  In the fifth projection pattern PP5, the first bright portion B11 and the first bright portion B21 are different bright portion systems. Similarly, the first bright section B21 and the first bright section B31 are different bright section systems. Furthermore, in the first bright portion B31 and the second bright portion B12, the second bright portion B12 and the second bright portion B22, and the second bright portion B22 and the second bright portion B32, respectively, the bright portions included in different bright portion systems is there. Therefore, in the fifth projection pattern PP5, a dark portion G1 having a width W2 of the dark portion is disposed between each of all the bright portions B11, B21, B31, B12, B22, and B32. Then, the relationship of Expression 1 holds between the width W2 of the dark part and the width W1 of the bright part. In addition, between the first bright portion B11 and the second bright portion B12 of the first bright portion system BR1, between the first bright portion B21 and the second bright portion B22 of the second bright portion system BR2, and the third bright portion The width between the first bright portion B31 and the second bright portion B32 of the system BR3 has a relationship of several 2.

  That is, the width W2 of the dark portion is set such that the relationship between Equation 1 and Equation 2 is satisfied. For example, in the fifth projection pattern PP5, L = 3. Therefore, by setting K = 2 and N = 0, the dark portion width W2 is 2/3 times the bright portion width W1. In the fifth projection pattern PP5, a dark portion G1 having a dark portion width W2 that is 2/3 times the bright portion width W1 is disposed between each of the six bright portions. At this time, the space between the first bright portion B11 and the second bright portion B12 is four times the width W1 of the bright portion, and satisfies the formula 2.

  In the surface inspection apparatus A4, assuming that the number of bright parts included in the bright part system is P, P = 2, and it becomes the imaging timing every time the inspection area CP moves twice the width of the bright part.

  The inspection area CP is equally divided into 12 as in the first embodiment, as it moves from left to right in FIG. Then, numbers 1 to 12 are sequentially assigned to each of the divided areas of the inspection area CP from left to right. Then, the 12-divided portion is further divided into three equal parts, and a code of _a, _b, or _c is assigned to each divided portion. For example, 1_a, 1_b, and 1_c are arranged at the left end from the left. Then, on the right side, 2_a, 2_b, 2_c, 3_a and so on continue. And 12_a, 12_b, 12_c is arrange | positioned from the left at the right end side.

  In the surface inspection apparatus A4, when the front end of the movement direction D1 of the inspection area CP, that is, 12_c is in the first bright part B11, the control unit 30 operates the imaging unit 10 as the first imaging timing to start Get the shooting data of Then, the control unit 30 performs imaging as the imaging timing every time the inspection area CP moves twice the width W1 of the bright part. Then, the control unit 30 ends the inspection when the rear end in the movement direction of the inspection area CP passes through the bright portion B3.

  By performing imaging in this way, the first bright part B11 and the second bright part B12 of the first bright part system BR1 are in the region r_c, the region (r + 1) _a, and the region (r + 1) _b (r is an integer), Projected alternately. The first bright part B21 and the second bright part B22 of the second bright part system BR2 are alternately projected onto the area s_b, the area s_c and the area (s + 1) _a (s is an integer). The first bright part B31 and the second bright part B32 of the third bright part system BR3 are alternately projected onto the area t_a, the area t_b and the area t_c (q is an integer). The portions where the bright portions of the bright portion systems BR1, BR2, and BR3 of the region to be inspected CP in the imaging data are shifted by 1/3 of the width W1 of the bright portion. As described above, in the surface inspection apparatus A4, inspection can be performed with a degree of redundancy 3 and a degree of definition 3.

  Then, in the surface inspection apparatus A4, the imaging timing is obtained each time the inspection area CP moves twice the width W1 of the bright part, so when the imaging unit 10 has sufficient performance, the moving speed of the inspection area CP Can be doubled. Therefore, it is possible to reduce the time required for the inspection to about half. Further, even if the movement speed of the inspection area CP is the same as in the case where the imaging timing comes every time the width W1 of the bright part moves, the number of imaging timings is reduced, so the number of image processing and inspection of abnormality is reduced. As a result, the time required for the inspection can be reduced, and the burden on the control unit 30, the image processing unit 40, the storage unit 70, and the like can be reduced.

  Other features are the same as those of the first embodiment.

  In the surface inspection apparatus, it is possible to increase redundancy and definition. Further, by adopting a configuration including a plurality of bright portions in the bright portion system, it is possible to reduce the time required for processing or reduce the processing itself. Thus, the surface inspection apparatus can perform inspection more accurately and more reliably than the conventional surface inspection apparatus.

  In each of the above-described embodiments, the first imaging timing is when the front end of the inspection area CP overlaps with the uppermost divided part divided by the number of bright part bright parts. However, the present invention is not limited to this. If the front end is in the most upstream segment, it does not have to completely overlap.

  When the above-described embodiments are combined, the surface inspection apparatus according to the present invention can irradiate the entire bright area substantially the same number of times as the number of bright part systems. Further, it is possible to irradiate by shifting the width of the bright part by the width divided by the number of bright parts included in the bright part system, and it is possible to increase the inspection accuracy accordingly. Furthermore, assuming that the number of bright parts included in the bright part system is P, the surface inspection apparatus according to the present invention has an inspection area compared to a conventional surface inspection apparatus that performs imaging each time the width W1 of the bright part moves. The time required for the inspection or the amount of information processing can be set to 1 / P.

Sixth Embodiment
In the surface inspection apparatus according to the present invention, an abnormality is detected by photographing the inspection region CP on which the bright portion is projected and performing image processing. Depending on the region CP to be inspected, there may be a portion having a different surface color due to painting, surface treatment, or the like. Depending on the combination of the color of the surface of the inspection area CP and the color of the bright part (that is, the color temperature of the light emitted from the light source), detection of an abnormality may be difficult. Therefore, the surface inspection apparatus according to the present invention may be provided with a light source for emitting light having different color temperatures so that the color of the bright part is different for each bright part system. By doing this, it is possible to spread and project light portions of different color temperatures all over the inspection area, and it is possible to improve the accuracy of detecting an abnormality.

  In each of the above-described embodiments, for easy explanation, the length of the inspection area CP is short, and the time required for the inspection area to pass in front of the illumination unit is short. Therefore, with respect to the period from the start to the end of the inspection, the ratio of the period immediately after the start of the inspection and a part where the bright part near the end of the inspection is not projected is large with respect to the entire inspection period. On the other hand, the surface inspection apparatus of the present invention is used to perform surface inspection of an inspection object using an automobile, a train, or the like as an inspection object and using the surface of the inspection object as an inspection area. When inspecting such a long inspection area, it takes a long time for the inspection area to pass in front of the illumination unit. The period in which some bright parts are not projected immediately after the start of inspection and just before the end of the inspection is constant regardless of the length of the region to be inspected, and the ratio decreases as the region to be inspected becomes longer. As a result, the effect of time reduction is increased.

  Moreover, although the surface inspection apparatus shown above has mentioned what the test target object has moved with respect to the illumination part, it is not limited to this. The illumination unit may be configured to move relative to the inspection object at rest. At this time, the photographing unit may also move in conjunction with the illumination unit. Moreover, although the surface inspection apparatus according to the present invention includes one imaging unit, the present invention is not limited to this, and a plurality of imaging units may be provided. When a plurality of imaging units are provided, the imaging data captured by each imaging unit may be individually processed to detect an abnormality, or images captured by at least two imaging units may be combined once An anomaly may be detected.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this content. Moreover, the embodiment of the present invention can add various modifications without departing from the spirit of the invention.

A, A1, A2, A3, A4 Surface inspection apparatus 10 Imaging unit 20 Illumination unit 21 Light source 22 Diffuser plates 23, 23a, 23b, 23c, 23d Mask member 231 Open window 24 Light band 25 Non-illumination band 30 Control unit 31 Calculation unit 40 image processing unit 50 transport unit 60 display unit 70 storage units B, B1, B2, B3, B4 bright portions B11, B21, B31 first bright portions B12, B22, B32 second bright portions BR1 first bright portion system BR2 2 Bright section system BR3 Third bright section system BR4 Fourth bright section system CA Examination object CP Inspection area G, G0, G1, G2 Dark section PP Projection pattern PP1 1st projection pattern PP2 2nd projection pattern PP3 3rd projection pattern PP4 Fourth projection pattern PP5 Fifth projection pattern W1 Bright portion widths W2, W21, W22 Dark portion width D1 Movement direction

Claims (10)

An illumination unit that emits illumination light to form a projection pattern on the surface of the inspection area;
An imaging unit configured to image an examination area moving relative to the illumination unit;
A control unit that controls the imaging timing of the imaging unit so as to image the inspected area every time the inspected area moves a certain distance;
In the projection pattern, a plurality of bright portions and a plurality of dark portions that are darker than the bright portions are alternately arranged in the moving direction of the inspection region,
The projection pattern includes a plurality of sets of bright portion systems provided with one or more bright portions,
The control unit sets the first photographing timing when the bright portion projected first on the inspection region is at the front end in the moving direction of the inspection region, and the previous photographing timing in each bright portion system. The bright part is projected on a part other than the part where the bright part is projected on the inspected area, and the bright part is projected on the entire area of the inspected area without gaps. The surface inspection apparatus which controls the imaging | photography timing of the said imaging | photography part so that it may project on the position which the width | variety smaller than the width | variety of the bright part shifted with respect to the bright part of other bright part system.   The surface inspection apparatus according to claim 1, wherein a distance between bright portions arranged at both ends of the projection pattern is shorter than a length of the region to be inspected. Each of the bright section systems includes a plurality of bright sections,
The interval between the bright parts included in the same bright part system is M times the width of the bright part (M is an integer of 1 or more),
2. The interval between bright parts included in different bright part systems is (N + K / L) times the width of the bright part (N is 0 or an integer, and K and L are integers satisfying K <L). Or the surface inspection apparatus of Claim 2.   The surface inspection apparatus according to claim 3, wherein L is the number of bright part systems included in the projection pattern.   The surface inspection apparatus according to claim 3 or 4, wherein the K is a number having no positive common divisor other than 1 or the L and 1. The control unit controls the imaging timing of the imaging unit so as to capture the inspection area each time the inspection area moves P times (P is an integer) of the width of the bright part.
The surface inspection apparatus according to claim 3, wherein P is the number of bright portions included in a bright portion system.   The surface inspection apparatus according to claim 6, wherein the M does not satisfy (M + 1) × (k−1) = P × n (k is a positive integer smaller than P and n is a positive integer).   The surface inspection apparatus according to claim 1, wherein the illumination unit projects a bright part irradiated with light having a different color temperature for each bright part system.   The surface inspection apparatus according to any one of claims 1 to 8, wherein the inspection area is moving.   The surface inspection apparatus according to any one of claims 1 to 9, wherein the illumination unit is moving.

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