Surface analysis system and surface analysis method

Abstract

To provide a surface analysis system for analyzing the surface of a workpiece by a phase shift method, with which it is possible to simply obtain a captured image in which a striped pattern of a clear sine waveform is projected and simply change a condition for the striped pattern, without being restrained by the distance to the workpiece or the angle of irradiation.SOLUTION: Provided is a surface analysis system comprising: a line sensor camera for capturing an image of the workpiece surface to be analyzed; a light irradiation device for irradiating the imaging region of the line sensor camera with analysis light; a scan mechanism for scanning the imaging region on the analysis surface in a direction crossing the line direction; a dimmer unit for changing the irradiation intensity of the analysis light as suitable for scanning of the imaging region; and a surface analysis unit for analyzing the shape of the surface to be analyzed by a phase shift method on the basis of the striped pattern image generated from a plurality of line images captured by the line sensor camera.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a surface analysis system and a surface analysis method for analyzing the surface of a workpiece by a phase shift method. [Background technology]

[0002] Conventionally, to detect distortions or scratches on the surface of a workpiece, a surface analysis system that uses a so-called phase shift method is known, in which a light irradiation device that emits light in a striped pattern and has a light-emitting surface that can shift the phase (a so-called phase shift lighting device) is used to project a striped pattern onto the surface of the workpiece, and the workpiece surface is imaged while shifting the phase of the striped pattern, and the surface shape of the workpiece is analyzed based on the multiple captured images obtained (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-158458 A Summary of the Invention [Problem to be solved by the invention]

[0004] In such a surface analysis system, from the viewpoint of image processing using the phase shift method, it is desirable that the stripe pattern projected on the surface of the workpiece has an illuminance profile along the phase transition direction that is an accurate sine wave shape. However, when light is irradiated from a light-emitting surface that emits light in a stripe pattern, the profile of the stripe pattern projected on the surface of the workpiece tends to have sharp peaks and flat valleys compared to an accurate sine wave shape, or the illuminance at both ends tends to be lower than the illuminance at the center, as shown in Figure 7, depending on the distance between the light irradiation device and the workpiece (LWD: Light Work Distance), making it difficult to obtain an accurate sine wave illuminance profile.

[0005] Therefore, the LWD is adjusted to make the illuminance profile as close to an accurate sine wave as possible, but the illuminance profile of the stripe pattern projected onto the surface of the workpiece is sensitive to changes in LWD, so the range of LWD that can realize an illuminance profile shape that allows acceptable surface analysis is very limited. On the other hand, as a prerequisite for realizing a clean sine wave illuminance profile, it is necessary to position the light irradiation device so that the light emitting surface that emits light in a stripe pattern faces the surface of the workpiece. Therefore, in order to obtain a clean sine wave illuminance profile, both the LWD and the irradiation angle are limited, resulting in a problem of low freedom in system placement.

[0006] Furthermore, the LWD range that can achieve an appropriate illuminance profile shape varies depending on the conditions of the stripe pattern (spacing, width, or contrast). Therefore, if the conditions of the stripe pattern are changed, it is necessary to find again the very limited appropriate LWD range accordingly, which creates the problem that the conditions of the stripe pattern cannot be easily changed.

[0007] The present invention has been made to solve all of the above-mentioned problems at once, and its main object is to provide a surface analysis system that analyzes the surface of a workpiece using the phase shift method, which can easily obtain an image on which a clean sinusoidal waveform stripe pattern is projected, without being restricted by the distance from the workpiece or the irradiation angle, and can easily change the conditions of the stripe pattern. [Means for solving the problem]

[0008] That is, the surface analysis system of the present invention is characterized by comprising a line sensor camera that images the surface of the workpiece to be analyzed, a light irradiation device that irradiates the imaging area of ​​the line sensor camera with analysis light, a scanning mechanism that scans the imaging area on the surface to be analyzed in a direction intersecting its line direction, a light adjustment unit that changes the irradiation intensity of the analysis light in accordance with the scanning of the imaging area, and a surface analysis unit that analyzes the shape of the surface to be analyzed by a phase shift method based on a striped pattern image generated from a plurality of line-shaped images captured by the line sensor camera.

[0009] Furthermore, the surface analysis method of the present invention is characterized in that the surface to be analyzed of the workpiece is imaged with a line sensor camera, analysis light is irradiated onto the imaging area of ​​the line sensor camera, the imaging area is scanned on the surface to be analyzed in a direction intersecting the line direction, the irradiation intensity of the analysis light is changed in accordance with the scanning of the imaging area, and the shape of the surface to be analyzed is analyzed by a phase shift method based on a striped pattern image generated from a plurality of line-shaped images captured by the line sensor camera. Effect of the Invention

[0010] According to the present invention configured in this manner, in a surface analysis system that analyzes the surface of a workpiece using the phase shift method, it is possible to easily obtain an image on which a clean sinusoidal stripe pattern is projected, without being restricted by the distance from the workpiece or the irradiation angle, and it is also possible to easily change the conditions of the stripe pattern. [Brief description of the drawings]

[0011] [Figure 1] 1 is a schematic overall view of a surface analysis system according to an embodiment of the present invention, viewed from the side; [Diagram 2] FIG. 2 is a functional block diagram of the surface analysis system according to the embodiment. [Diagram 3] 5A and 5B are schematic diagrams showing an example of change in irradiation intensity of analyzing light controlled by a light adjustment unit in the embodiment. [Figure 4] 5A and 5B are schematic diagrams showing an example of a method for generating a striped pattern image by the image generating unit of the embodiment. [Diagram 5] 5A to 5C are schematic diagrams showing examples of stripe pattern images with different phases obtained by the image generating unit of the embodiment. [Figure 6] 5 is a schematic diagram showing irradiation intensity profiles of a plurality of stripe pattern images generated by the image generating unit of the embodiment. FIG. [Figure 7] FIG. 4 is a schematic diagram showing an example of an illuminance profile of stripe pattern light obtained using a phase shift illumination device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] A surface analysis system 100 according to an embodiment of the present invention will be described below with reference to the drawings.

[0013] The surface analysis system 100 of this embodiment is for analyzing the shape of the analyzed surface Wa by the phase shift method based on a plurality of captured images (also called stripe pattern images) in which light of a stripe pattern with different phases is projected onto the analyzed surface Wa of the workpiece W, and detecting surface distortion and scratches. Specifically, as shown in FIG. 1, the surface analysis system 100 includes a line sensor camera 1 that captures the analyzed surface Wa of the workpiece W, a light irradiation device 2 that irradiates the imaging area of ​​the line sensor camera 1 with light (also called analysis light), a scan mechanism 3 that scans the imaging area on the analyzed surface Wa of the workpiece W, a power supply device 4 that supplies power to the light irradiation device 2 and controls its light emission mode, and a calculation device 5 that analyzes the shape of the analyzed surface Wa based on the captured images. The surface analysis system 100 of this embodiment is configured to analyze the shape of the analyzed surface Wa based on four stripe pattern images with phases shifted by π / 2 each.

[0014] The line sensor camera 1 comprises a linear light receiving sensor (not shown) housed inside the housing 11, a line optical system (not shown) arranged in front of the light receiving sensor, and an output section (not shown) that transmits image data representing the image captured by the light receiving sensor, and is configured so as to be able to capture an image of the surface to be analyzed Wa from a strip-shaped light incident surface 1a that opens on one side of the housing 11.

[0015] The light incident surface 1a of the line sensor camera 1 faces (is directly facing) the surface Wa of the workpiece W to be analyzed, and a line-shaped imaging area on the surface Wa to be analyzed is imaged by one imaging by the line sensor camera 1. The line sensor camera 1 is set to capture images one after another at a predetermined short time interval. A plurality of line-shaped images (also called line-shaped images) captured by the line sensor camera 1 are output to the calculation device 5. In this embodiment, the captured plurality of line-shaped images (specifically, all of the line-shaped images of the surface Wa to be analyzed) are connected by the line sensor camera 1 and output to the calculation device 5 as a single area image. However, this is not limited to this, and the plurality of line-shaped images may be output to the calculation device 5 as individual images without being treated as a single area image.

[0016] The light irradiation device 2 includes an LED as a light source, and its brightness (specifically, irradiation intensity), light emission time, and light emission timing are controlled by the power supplied from the power supply device 4. The light irradiation device 2 of this embodiment is a line light irradiation device 2 that irradiates a line-shaped light onto the imaging area of ​​the line sensor camera 1 on the surface Wa to be analyzed. This light irradiation device 2 irradiates a line-shaped light onto the entire imaging area of ​​the line sensor camera 1 on the surface Wa to be analyzed, and is installed so that the line direction (longitudinal direction) of the irradiation area coincides with the line direction (longitudinal direction) of the imaging area.

[0017] The surface analysis system 100 of this embodiment includes a beam splitter 6 (specifically, a half mirror) disposed at an angle (approximately 45°) on an imaging axis connecting the light receiving elements of the line sensor camera 1 and the analyzed surface Wa of the workpiece W. The light irradiation device 2 is disposed so as to irradiate light toward the beam splitter 6, and the light emitted from the light irradiation device 2 is reflected by the beam splitter 6 and irradiated onto the analyzed surface Wa of the workpiece W from the same axis as the imaging axis of the line sensor camera 1. That is, in this embodiment, the line sensor camera 1 and the light irradiation device 2 form a coaxial epi-illumination structure.

[0018] The scanning mechanism 3 is for scanning the imaging area of ​​the line sensor camera 1 on the analyzed surface Wa of the workpiece W in a direction intersecting the line direction (specifically, a direction perpendicular to the line direction). The scanning mechanism 3 of this embodiment is configured to scan the imaging area on the analyzed surface Wa by moving the workpiece W in a direction perpendicular to the line direction of the fixed imaging area. Specifically, the scanning mechanism 3 of this embodiment is configured by a conveyor device that transports the workpiece W in one direction (a direction perpendicular to the line direction of the imaging area). The scanning mechanism 3 is configured to transport the workpiece W so that the analyzed surface Wa moves at a constant speed relative to the imaging area. The scanning mechanism 3 of this embodiment is configured to move the analyzed surface Wa only in one direction without moving the analyzed surface Wa back and forth relative to the imaging area while the imaging of the analyzed surface Wa is being performed sequentially by the line sensor camera 1. In other words, the imaging area of ​​the line sensor camera 1 is configured to scan the analyzed surface Wa only once.

[0019] The power supply device 4 supplies power to the light irradiation device 2 via a power supply cord and controls the light emission mode. Specifically, the power supply device 4 functions as a dimming unit 41 that adjusts the brightness (irradiation intensity) of the light emitted from the light irradiation device 2 by controlling the current value supplied to the light irradiation device 2 based on dimming setting information, which is information related to a dimming value stored in advance.

[0020] The calculation device 5 is a so-called computer equipped with a CPU, a memory, an I / O port, etc. The calculation device 5 performs at least the functions of an image data acquisition unit 51, an image generation unit 52, and a surface analysis unit 53 as shown in Fig. 2, by the CPU and peripheral devices working together in accordance with a program stored in the memory.

[0021] The image data acquisition unit 51 acquires a plurality of line-shaped images output from the line sensor camera 1 and sequentially outputs the acquired line-shaped images to the image generation unit 52. In this embodiment, the image data acquisition unit 51 acquires a plurality of line-shaped images as one area image by connecting the images together, and outputs the one area image to the image generation unit 52.

[0022] The image generating unit 52 extracts a plurality of line-shaped images from the received area image, and then stitches together the extracted plurality of line-shaped images to generate a two-dimensional striped pattern image in which a striped pattern is projected onto the analyzed surface Wa of the workpiece W. The image generating unit 52 generates a plurality of (here, four) striped pattern images that are out of phase with each other from one area image.

[0023] The surface analysis unit 53 analyzes the shape of the analyzed surface Wa by a phase shift method using multiple stripe pattern images with different phases generated based on the line image. Specifically, the surface analysis unit 53 performs phase analysis from the luminance values ​​of the multiple stripe pattern images and calculates the three-dimensional coordinates of each pixel to analyze the surface shape of the analyzed surface Wa.

[0024] In the surface analysis system 100 of this embodiment, the light adjustment unit 41 of the power supply device 4 is configured to change the irradiation intensity of the analysis light irradiated from the light irradiation device 2 in accordance with the scanning of the imaging area on the inspected surface. In this embodiment, the image generation unit 52 is configured to generate a plurality of stripe pattern images in which stripe pattern light with mutually shifted phases is projected based on a plurality of line-shaped images captured while changing the irradiation intensity, and the surface analysis unit 53 is configured to analyze the surface shape of the analyzed surface Wa of the workpiece W based on the plurality of stripe pattern images.

[0025] The light adjustment unit 41 is configured to change the irradiation intensity of the analytical light for each line (specifically, for each line) that is sequentially imaged by the line sensor camera 1. Specifically, the light adjustment unit 41 changes the irradiation intensity of the analytical light each time the line sensor camera 1 finishes imaging one line, and the imaging area irradiated with the analytical light with the changed irradiation intensity is imaged by the line sensor camera 1 as the next line.

[0026] FIG. 3 shows an example of the change in the irradiation intensity of the analyzing light controlled by the light adjustment unit 41. The number of stripe pattern images used to analyze the analyzed surface Wa is n (an integer equal to or greater than 2; in this embodiment, n=4). As shown in FIG. 3, the dimming unit 41 changes the irradiation intensity of the analysis light so that, in a profile with the horizontal axis representing the number of lines and the vertical axis representing the irradiation intensity, the irradiation intensity of the analysis light for every n lines changes in a periodic waveform and the phases of the irradiation intensities of consecutive n lines are shifted from each other by 2π / n.

[0027] More specifically, the light adjusting unit 41 changes the irradiation intensity of the analysis light so that the waveform connecting the irradiation intensities of the (4×m+1)th line, the waveform connecting the irradiation intensities of the (4×m+2)th line, the waveform connecting the irradiation intensities of the (4×m+3)th line, and the waveform connecting the irradiation intensities of the (4×m+4)th line each have a periodic wave shape, where m is an integer equal to or greater than 0. Each waveform has the same period and the same amplitude, and in this embodiment, each has a sine wave shape. In this embodiment, the irradiation intensity of the analysis light is changed so that the phases of the irradiation intensities of four consecutive lines (for example, the first line to the fourth line, the fifth line to the eighth line, etc.) are shifted from each other by π / 2.

[0028] In this embodiment, the image generating unit 52 sequentially connects the line-shaped images of every n lines to generate n stripe pattern images. More specifically, as shown in FIG. 4, a plurality of (4×m+1)-th line-shaped images are extracted from one area image, and these are sequentially connected to generate one stripe pattern image. This is similarly performed for a plurality of (4×m+2)-th line-shaped images, a plurality of (4×m+3)-th line-shaped images, and a plurality of (4×m+4)-th line-shaped images, to generate four stripe pattern images as shown in FIG. 5. The illuminance profiles of the four stripe pattern images thus obtained are shifted in phase by π / 2 each, as shown in FIG. 6.

[0029] Here, the image generating unit 52 generates the striped pattern image by treating the length of one pixel in the scanning direction of the striped pattern image as n times the length of one pixel in the scanning direction of the line image. In other words, the image generating unit 52 generates the striped pattern image by treating one line image extracted every n lines as representative data for the continuous n lines.

[0030] The surface analysis unit 53 then performs phase analysis on the n stripe pattern images thus generated, the phases of which are shifted from one another, to analyze the surface shape of the analysis target surface Wa.

[0031] According to the surface analysis system 100 of this embodiment configured as described above, by changing the irradiation intensity of the analysis light irradiated onto the imaging area of ​​the line sensor camera 1 and scanning the imaging area on the analyzed surface Wa of the workpiece W, it is possible to generate multiple (4) stripe pattern images in which stripe pattern light with mutually shifted phases is projected onto the analysis surface Wa based on the multiple line-shaped images captured by the line sensor camera 1 in one scan.

[0032] In this way, the illuminance profile of the striped pattern obtained using the line sensor camera 1 and the dimmable light irradiation device 2 depends on the change in the irradiation intensity of the light irradiated into the linear imaging area, and is not significantly affected by the distance (LWD) from the workpiece W or the irradiation angle as in the conventional system configuration using a phase shift lighting device. Therefore, the line sensor camera 1 and the light irradiation device 2 can be installed with a high degree of freedom without being limited by the LWD or the irradiation angle.

[0033] In addition, since the change in the irradiation intensity of the analysis light irradiated to the imaging area appears as a profile of the stripe pattern, it is possible to easily obtain an image in which a beautiful sinusoidal stripe pattern is projected by changing the irradiation intensity of the analysis light in a sinusoidal waveform in accordance with the scanning of the imaging area. Moreover, by adjusting the change in the irradiation intensity of the analysis light irradiated to the imaging area, it is possible to easily change the conditions (spacing, width, or contrast) of the stripe pattern projected onto the workpiece W.

[0034] The present invention is not limited to the above-described embodiment. For example, in the above embodiment, the light irradiation device 2 irradiates a line-shaped light, but this is not limited thereto. The light irradiation device 2 in other embodiments may be a surface light emitting device having a rectangular light emitting surface, for example, a square. Even in this case, the effect of the present invention can be achieved as long as the light irradiated from the light irradiation device 2 is configured to irradiate the entire imaging area of ​​the line sensor camera 1.

[0035] In the surface analysis system 100 of the embodiment, the imaging area of ​​the line sensor camera 1 scans the analyzed surface Wa only once, and in this one scanning operation, the light adjustment unit 41 changes the irradiation intensity of the analysis light so that the irradiation intensity of the analysis light for every n lines changes to a periodic waveform and the phases of the irradiation intensities of the consecutive n lines are shifted from each other by 2π / n, but this is not limited to the above. In the surface analysis system 100 of another embodiment, for example, the imaging area of ​​the line sensor camera 1 may scan the analyzed surface Wa multiple times (for example, n times) by moving the workpiece W back and forth relative to the imaging area. In this case, the light adjustment unit 41 may change the irradiation intensity of the analysis light for each line in each scanning operation to a periodic waveform and change the irradiation intensity of the analysis light so that the phases of the waveforms are shifted from each other by 2π / n between each scan.

[0036] In the above embodiment, the light adjustment unit 41 changes the irradiation intensity of the analyzing light so that the phases of the irradiation intensities of the consecutive n lines are shifted from each other by 2π / n, but this is not limited to the above. As long as the phases of the irradiation intensities of the consecutive n lines are shifted from each other by 2π / n, it is not necessary to change the irradiation intensities in the order of the phases.

[0037] Furthermore, the surface analysis system of the above embodiment is configured to analyze the shape of the analyzed surface Wa based on four stripe pattern images with different phases, but is not limited to this. Surface analysis systems of other embodiments may be configured to analyze the shape of the analyzed surface Wa based on two, three, or five or more stripe pattern images with different phases.

[0038] In other embodiments, the line sensor camera 1 and the light projection device 2 do not need to have a coaxial epi-illumination structure, and the light projection device 2 may use so-called low-angle lighting or high-angle lighting.

[0039] Furthermore, in the above embodiment, the scanning mechanism 3 uses a conveyor device to move the analyzed surface Wa of the workpiece W relative to the imaging region, but is not limited to this. In other embodiments, the scanning mechanism 3 may be configured, for example, by a robot arm having the imaging device and the light irradiation device 2 attached to its tip, and configured to move the imaging region relative to the analyzed surface Wa of the workpiece W.

[0040] Additionally, the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit and scope of the present invention.

[0041] For example, the surface analysis system and the surface analysis method of the present invention include the following aspects.

[0042] (Aspect 1) A surface analysis system comprising: a line sensor camera that images a surface of a workpiece to be analyzed; a light irradiation device that irradiates an imaging area of ​​the line sensor camera with analytical light; a scanning mechanism that scans the imaging area on the surface to be analyzed in a direction intersecting the line direction of the imaging area; a light adjustment unit that changes the irradiation intensity of the analytical light in accordance with the scanning of the imaging area; and a surface analysis unit that analyzes the shape of the surface to be analyzed by a phase shift method based on a striped pattern image generated from a plurality of line-shaped images captured by the line sensor camera.

[0043] In this embodiment, by scanning the imaging area of ​​the line sensor camera on the surface to be analyzed of the workpiece while changing the irradiation intensity of the analysis light irradiated on the imaging area, it is possible to generate a plurality of stripe pattern images in which the phase-shifted stripe pattern light is projected on the analysis surface based on a plurality of line images captured by the line sensor camera. For example, by changing the irradiation intensity of the analysis light into a sinusoidal waveform in accordance with the scanning of the imaging area, it is possible to obtain a stripe pattern image in which the stripe pattern light in which light and dark are alternately switched is projected on the analysis surface. In addition, by shifting the phase of the waveform of the analysis light irradiated on the imaging area, stripe pattern images with different phases can be obtained.

[0044] In this way, the illuminance profile of the striped pattern obtained using a line sensor camera and a dimmable light projection device depends on the change in the illuminance intensity of the light projected into the linear imaging area, and is not significantly affected by the distance from the work (LWD) or the projection angle as in the conventional system configuration using a phase shift lighting device. Therefore, the line sensor camera and the light projection device can be installed with a high degree of freedom without being limited by the LWD or projection angle.

[0045] In addition, since the change in the irradiation intensity of the analysis light irradiated to the imaging area appears as a profile of the stripe pattern, it is possible to easily obtain an image in which a beautiful sinusoidal stripe pattern is projected by changing the irradiation intensity of the analysis light in a sinusoidal waveform in accordance with the scanning of the imaging area. Moreover, by adjusting the change in the irradiation intensity of the analysis light irradiated to the imaging area, it is possible to easily change the conditions (spacing, width, or contrast) of the stripe pattern projected onto the workpiece.

[0046] (Aspect 2) The surface analysis system described in aspect 1 further includes an image generation unit that generates a plurality of stripe pattern images from the plurality of line-shaped images, in which stripe pattern light is projected with phase-shifted stripe patterns, and the surface analysis unit analyzes the shape of the analyzed surface based on the generated plurality of stripe pattern images.

[0047] (Aspect 3) The surface analysis system according to aspect 2, wherein the light adjustment unit changes the irradiation intensity of the analysis light for each line that is sequentially imaged by the line sensor camera. In this embodiment, the luminance can be changed for each line (that is, for each pixel in the scanning direction), so that an image projected with a clearer sinusoidal stripe pattern can be obtained.

[0048] (Aspect 4) The surface analysis system described in aspect 3, wherein the surface analysis unit analyzes the shape of the surface to be analyzed based on n (n is an integer greater than or equal to 2) striped pattern images whose phases are shifted at approximately equal intervals, the light adjustment unit changes the irradiation intensity of the analysis light so that the irradiation intensity of the analysis light for every n lines changes in a periodic waveform and the phases of the irradiation intensities of consecutive n lines are shifted from each other by 2π / n, and the image generation unit connects the line-shaped images for every n lines to generate n striped pattern images. In this embodiment, a plurality of stripe pattern images with mutually shifted phases can be obtained by scanning the imaging area once, and therefore the time required for analysis can be shortened compared to the case of performing reciprocating scanning. Note that the obtained stripe pattern image is a combination of line-shaped images of n lines, and therefore contains some errors compared to a stripe pattern image obtained by combining line-shaped images of each line, but the error (an error of a few pixels) is sufficiently small compared to the size of scratches, etc., to be detected by analyzing the surface, and therefore there is no problem in terms of resolution.

[0049] (Aspect 5) 5. The surface analysis system according to any one of aspects 1 to 4, wherein the light irradiation device is a line light irradiation device that irradiates the imaging region with a line-shaped analyzing light. In this embodiment, the entire system can be made smaller than when a surface-emitting lighting device is used. In particular, when a coaxial unit having a beam splitter or the like is used to configure the line sensor camera and the light projection device to have a coaxial epi-illumination structure, the coaxial unit itself can be made smaller, so that the effect is even more pronounced. When a robot arm or the like is used as the scanning mechanism 3 to move the light projection device and the line sensor camera, the effect of the miniaturization becomes even more pronounced. In addition, when a surface-emitting illumination device is used, the imaging area is irradiated with analysis light at various irradiation angles, but when a line-light illumination device is used, the imaging area can be irradiated with analysis light at a substantially constant irradiation angle, making it possible to grasp the shape of the analyzed surface more accurately and to easily detect surface defects such as scratches that exist on the analyzed surface. This effect is particularly noticeable when the analyzed surface is irradiated with analysis light at a low angle or a high angle.

[0050] (Aspect 6) A surface analysis method comprising the steps of: capturing an image of a surface of a workpiece to be analyzed with a line sensor camera; irradiating an imaging area of ​​the line sensor camera with analytical light; scanning the imaging area on the surface to be analyzed in a direction intersecting the line direction of the imaging area; varying the irradiation intensity of the analytical light in accordance with the scanning of the imaging area; and analyzing the shape of the surface to be analyzed by a phase shift method based on a striped pattern image generated from a plurality of line-shaped images captured by the line sensor camera. Such a surface analysis method can achieve the same effects as those of the above-mentioned surface analysis system of the present invention. [Explanation of symbols]

[0051] 100 Surface Analysis System 1. Line sensor camera 2...Light irradiation device 3. Scanning mechanism 41....Light control section 53...Surface analysis section W ···Work Wa...surface to be analyzed

Claims

1. A line sensor camera that captures an image of the surface of the workpiece to be analyzed; a light irradiation device that irradiates an imaging area of ​​the line sensor camera with analyzing light; a scanning mechanism for scanning the imaging region on the surface to be analyzed in a direction intersecting the line direction; a light control unit that changes the irradiation intensity of the analyzing light in accordance with scanning of the imaging area; a surface analysis unit that analyzes the shape of the surface to be analyzed by a phase shift method based on a striped pattern image generated from a plurality of line-shaped images captured by the line sensor camera.

2. an image generating unit that generates a plurality of stripe pattern images on which light of a stripe pattern having phases shifted from each other is projected from the plurality of line images, 2. The surface analysis system according to claim 1, wherein the surface analysis section analyzes the shape of the analyzed surface based on the generated plurality of stripe pattern images.

3. 3. The surface analysis system according to claim 2, wherein the light adjusting unit changes the irradiation intensity of the analysis light for each line that is sequentially imaged by the line sensor camera.

4. the surface analysis unit analyzes a shape of the analyzed surface based on n (n is an integer of 2 or more) stripe pattern images whose phases are shifted at substantially equal intervals, the light adjustment unit changes the irradiation intensity of the analyzing light so that the irradiation intensity of the analyzing light for each n lines changes in a periodic waveform and the phases of the irradiation intensities of the consecutive n lines are shifted from each other by 2π / n; 4. The surface analysis system according to claim 3, wherein the image generating section generates n stripe pattern images by stitching together line-shaped images of every n lines.

5. 2. The surface analysis system according to claim 1, wherein the light irradiation device is a line light irradiation device that irradiates the imaging region with a line-shaped analyzing light.

6. The surface of the workpiece to be analyzed is imaged with a line sensor camera, Irradiating an imaging area of ​​the line sensor camera with analyzing light; Scanning the imaging region on the surface to be analyzed in a direction intersecting the line direction; changing the irradiation intensity of the analyzing light in accordance with the scanning of the imaging region; A surface analysis method for analyzing the shape of the surface to be analyzed by a phase shift method based on a stripe pattern image generated from a plurality of line-shaped images captured by the line sensor camera.

Images