Light source diagnosis method and state inspection method

Abstract

To provide a light source diagnosis method that allows easy diagnosis of a state of a light source.SOLUTION: In an inspection device 1 that includes a holding table 11 having a holding surface 31 at least a part of which is made of a transparent member, a light source 22 arranged on one side of the holding surface 31, and an imaging unit 21 arranged on the other side of the holding surface 31, and that inspects a processing state of a workpiece 51 held on the holding table 11 and having division grooves formed along a planned division line, a light source diagnosis method of diagnosing a state of the light source 22 includes: a holding surface imaging step of emitting light from the light source 22 onto the holding surface 31 and imaging the light transmitted through the holding surface 31 with the imaging unit 21; and a light source diagnosis step of diagnosing the state of the light source 22 from the luminance of a transmission image 71 acquired in the holding surface imaging step.SELECTED DRAWING: Figure 1B

Description

[Technical field]

[0001] The present invention relates to a light source diagnosis method and a status inspection method. [Background technology]

[0002] An inspection device is known that holds a workpiece in which a division groove has been formed on a holding table having a holding surface formed of a transparent material that transmits at least a portion of light from a light source, irradiates one side of the holding surface with a light source, and acquires light that has passed through the holding surface and the division groove with an imaging unit arranged on the other side of the holding surface to inspect whether a division groove has been formed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-200694 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the conventional technology, when the light source deteriorates, the light transmitted through the workpiece weakens, making it impossible to properly inspect the dividing grooves formed in the workpiece. Therefore, there is a problem to be solved, which is to easily diagnose the condition of the light source.

[0005] The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a light source diagnosis method that makes it possible to easily diagnose the state of a light source. [Means for solving the problem]

[0006] The light source diagnosis method of the present invention is a light source diagnosis method for diagnosing the condition of a light source in an inspection device which inspects the machining condition of a workpiece held on the holding table and in which a division groove is formed along a planned division line, the inspection device comprising a holding table having a holding surface at least a portion of which is made of a transparent material, a light source arranged on one side of the holding surface, and an imaging unit arranged on the other side of the holding surface, the light source diagnosis method comprising: a holding surface imaging step of irradiating light from the light source to the holding surface and imaging the light that has transmitted through the holding surface with the imaging unit; and a light source diagnosis step of diagnosing the condition of the light source from the brightness of the image acquired in the holding surface imaging step.

[0007] The light source diagnosis method of the present invention may also include, if the luminance of the image is less than a threshold value in the light source diagnosis step, an adjustment step of adjusting a current value supplied to the light source so that the luminance of the image becomes equal to or greater than the threshold value.

[0008] In the light source diagnosis method of the present invention, in the adjusting step, if the luminance of the image does not become equal to or greater than the threshold value even when the current value supplied to the light source is increased to a predetermined value, the light source may be diagnosed as abnormal.

[0009] In the light source diagnosis method of the present invention, the holding surface imaging step is performed in multiple regions while moving the light source and the imaging unit facing the light source relatively in an X direction with respect to the holding surface, the light source has a plurality of light-emitting elements arranged along a Y direction perpendicular to the X direction, and the light source diagnosis step may diagnose an abnormality in the light-emitting elements when an image in which the luminance is continuously below a threshold value in the X direction is acquired, and diagnose an abnormality in the holding surface when an image in which the luminance is discontinuously below the threshold value in the X direction is acquired.

[0010] The state inspection method of the present invention is a state inspection method for inspecting the processing state of the workpiece using a light source diagnosis method, and before the holding surface imaging step and the light source diagnosis step, a division groove imaging step of holding the workpiece on the holding surface and irradiating the workpiece with the light source to image the light that has passed through the holding surface and the division groove, and a division determination step of determining that the workpiece has been divided if the division groove can be detected at the position of the planned division line in the image acquired in the division groove imaging step. Effect of the Invention

[0011] According to the present invention, the state of the light source can be easily diagnosed. [Brief description of the drawings]

[0012] [Figure 1A] FIG. 1 is a diagram illustrating an example of an inspection device that executes a light source diagnosis method according to an embodiment of the present invention. [Figure 1B] FIG. 1 is a diagram showing an example of an inspection device that performs the state inspection method of the present embodiment. [Diagram 2] FIG. 4 is a bottom view of the holding table of the present embodiment. [Diagram 3] FIG. 2 is a top view of the holding table of the present embodiment. [Figure 4A] 13 is an example of an image acquired when no abnormality is present in the holding surface imaging step of this embodiment. [Figure 4B] 13 is an example of an image acquired in the holding surface imaging step of the present embodiment when there is an abnormality in the light source. [Figure 4C] 13 is an example of an image acquired in the holding surface imaging step of this embodiment when there is an abnormality on the holding surface. [Figure 5A] 13 is an example of a groove image acquired when a division groove can be detected at the position of a planned division line in the division groove imaging step of this embodiment. [Figure 5B] 13 is an example of a groove image acquired when a division groove cannot be detected at the position of the planned division line in the division groove imaging step of this embodiment. [Figure 6]13 is a diagram illustrating an example of a light source according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] With reference to Figs. 1 to 6, a light source diagnosis method and an inspection device that executes the inspection method according to this embodiment will be described. The light source diagnosis method of this embodiment diagnoses the state of a light source provided in an inspection device that inspects the machining state of a workpiece. The light source diagnosis method of this embodiment includes a holding surface imaging step and a light source diagnosis step. The inspection device that executes the light source diagnosis method of this embodiment inspects the machining state of a workpiece held on a holding table by implementing a state inspection method. The state inspection method of this embodiment is performed before the holding surface imaging step and the light source diagnosis step. The state inspection method of this embodiment includes a division groove imaging step and a division determination step.

[0014] FIG. 1A is a diagram showing an example of an inspection device that executes the light source diagnosis method of this embodiment. FIG. 1B is a diagram showing an example of an inspection device that executes the state inspection method of this embodiment. FIG. 2 is a diagram showing a bottom view of the holding table of this embodiment. FIG. 3 is a diagram showing a top view of the holding table of this embodiment. FIG. 4A is an example of an image acquired when there is no abnormality in the holding surface imaging step of this embodiment. FIG. 4B is an example of an image acquired when there is an abnormality in the light source in the holding surface imaging step of this embodiment. FIG. 4C is an example of an image acquired when there is an abnormality in the holding surface in the holding surface imaging step of this embodiment. FIG. 5A is an example of a groove image acquired when a division groove can be detected at the position of the division planned line in the division groove imaging step of this embodiment. FIG. 5B is an example of a groove image acquired when a division groove cannot be detected at the position of the division planned line in the division groove imaging step of this embodiment. FIG. 6 is an example of a light source of another embodiment.

[0015] The inspection device 1 inspects the processing state of a workpiece such as a semiconductor wafer. The inspection device 1 can be used to inspect the workpiece before and after processing by a cutting device, a grinding device, a polishing device, a plasma processing device, a laser processing device, a bit cutting device, a tape application device, a tape peeling device, or the like. As shown in FIG. 1, the inspection device 1 includes a holding table 11, a light source 22, an imaging unit 21, and a control device 60. The inspection device 1 may include other configurations not shown in FIG. 1.

[0016] The control device 60 comprehensively controls each part of the inspection device 1. The control device 60 includes a control unit 61 including a processor or the like that executes various processes, and a storage unit 62 (memory).

[0017] The storage unit 62 of the control device 60 stores, as part of the control program of the inspection device 1, programs for executing various processes of the light source diagnosis method and state inspection method, various threshold values ​​for brightness, current value, etc.

[0018] The storage unit 62 is configured with one or more storage media such as a ROM (Read Only Memory) or a RAM (Random Access Memory) depending on the application.

[0019] The holding table 11 includes a holding surface 31 and a support 32. The holding surface 31 is formed of a circular plate-like surface capable of holding a workpiece 51 such as a wafer. The holding surface 31 may be formed of a rectangular plate-like surface such as a square or rectangle. At least a portion of the holding surface 31 is formed of a transparent member. The at least a portion of the transparent member may be formed of a material that can transmit at least a portion of the light irradiated from the light source 22, and includes transparent or translucent members.

[0020] 1B, when used as a state inspection method for inspecting the machining state of the workpiece 51, the holding table 11 holds the workpiece 51 transported by an arm or the like (not shown) vertically above (in the +Z direction) the holding surface 31. The state inspection method for inspecting the machining state of the workpiece 51 is used as an inspection device that, for example, after forming division starting points or division grooves in the workpiece 51, expands a support member fixed to the workpiece 51 and inspects whether the workpiece has been divided into a plurality of chips along the division starting points or division grooves.

[0021] The support body 32 is disposed vertically below the holding surface 31 (-Z direction) and is disposed so as to support the holding surface 31 vertically above (+Z direction). In this embodiment, the support body 32 is configured to have a cylindrical shape, but is not limited to this and may be configured to have a rectangular parallelepiped shape.

[0022] The imaging unit 21 is formed by a line sensor composed of an imaging element (CCD) or the like, and transmits an image signal captured to the control device 60. The imaging unit 21 is disposed at a position facing the light source 22. For example, as shown in FIG. 1A and FIG. 1B, the light source 22 is disposed vertically below the holding surface 31 (-Z direction), and the imaging unit 21 is disposed vertically above the holding surface 31 (+Z direction). That is, the light source 22 is disposed on one side of the holding surface 31, and the imaging unit 21 is disposed on the other side of the holding surface 31, with the holding surface 31 in between. In the above-mentioned embodiment, the light source 22 is disposed vertically below the holding surface 31 (-Z direction), and the imaging unit 21 is disposed vertically above the holding surface 31 (+Z direction), but this is not limited thereto. The light source 22 and the imaging unit 21 may be arranged in opposing positions across the holding surface 31, and the light source 22 may be arranged vertically above the holding surface 31 (+Z direction), and the imaging unit 21 may be arranged vertically below the holding surface 31 (-Z direction).

[0023] As shown in FIG. 2, the light source 22 is composed of a plurality of light emitting elements 41 such as LEDs arranged continuously along the Y-axis direction perpendicular to the X-axis direction. The control unit 61 can adjust the luminance of the light source 22 by changing the current value supplied to the light source 22 from a power supply unit (not shown). There is a correlation between the current value supplied to the light source 22 from the power supply unit and the luminance of the light source 22. That is, the control unit 61 can increase the luminance of the light source 22 by increasing the current value supplied to the light source 22. On the other hand, the control unit 61 can decrease the luminance of the light source 22 by decreasing the current value supplied to the light source 22. The light source 22 is formed so as to be longer than the diameter of the holding surface 31 along the radial direction (Y-axis direction) of the holding surface 31 formed in a circular shape. The plurality of light emitting elements 41 are arranged on the lower (-Z direction) side of the holding surface 31 of the holding table 11, and irradiate light from the lower (-Z direction) side of the holding surface 31 toward the upper (+Z direction) side.

[0024] 3, the imaging unit 21 has a plurality of imaging elements 42, such as CCDs, continuously arranged along the Y-axis direction perpendicular to the X-axis direction. The imaging unit 21 is formed along the radial direction (Y-axis direction) of the circularly formed holding surface 31 so as to be longer than the diameter of the holding surface 31. The plurality of imaging elements 42 are arranged on the upper (+Z direction) side of the holding surface 31 of the holding table 11, and capture images from the upper (+Z direction) side of the holding surface 31 toward the lower (-Z direction) side.

[0025] The light source 22 and the imaging unit 21 are formed to be movable relatively to the holding surface 31 along the X-axis direction by a moving mechanism (not shown) based on a control signal from the control unit 61. By moving the light source 22 and the imaging unit 21 relatively along the X-axis direction, an image of the entire holding surface 31 can be captured.

[0026] In the light source diagnosis method, a holding surface imaging step, a light source diagnosis step, and an adjustment step are performed. In addition, a state inspection method is performed before the holding surface imaging step and the light source diagnosis step. In the state inspection method, a division groove imaging step and a division determination step are performed. The state inspection method is performed to inspect the machining state of the workpiece 51 held on the holding table 11 and having division grooves formed along the planned division lines.

[0027] In the holding surface imaging step, as shown in Fig. 1A, before the workpiece 51 is held on the holding surface 31 of the holding table 11, the control device 60 controls the light source 22 to irradiate the holding surface 31 with light emitted from the light source 22, and controls the imaging unit 21 to move relatively to the holding surface 31 along the X-axis direction while imaging the holding surface 31. That is, the control unit 61 performs imaging of light transmitted through the holding surface 31 by the imaging unit 21 in a plurality of regions while moving the light source 22 and the imaging unit 21 relatively to the holding surface 31 in the X direction. Thereby, a holding surface image 70 of the holding surface 31 can be acquired as shown in Fig. 4A.

[0028] The holding surface image 70 has a transmission image 71 including light transmitted through the holding surface 31. Since at least a portion of the holding surface 31 is formed of a transparent material, the transmission image 71 captured by the light transmitted through the holding surface 31 is formed as a semi-transparent shadow. When there is no abnormality in the holding surface 31 or the light source 22, that is, when there is no foreign matter or scratch partially on the holding surface 31 or when there is no deterioration in the light source 22, the light irradiated from the light source 22 reaches the imaging unit 21 uniformly. Therefore, when there is no abnormality in the holding surface 31 or the light source 22, the transmission image 71 is formed with almost uniform brightness throughout the entire transmission image 71, as shown in FIG. 4A.

[0029] In the light source diagnosis step, the control unit 61 diagnoses the state of the light source 22 from the luminance of the transmission image 71 acquired in the holding surface imaging step. The luminance of the transmission image 71 can be determined based on the average value or total value of each pixel constituting the transmission image 71.

[0030] The control unit 61 can diagnose the state of the light source 22 based on whether the luminance of the transmission image 71 is less than a threshold value. The threshold value is a criterion for judging whether the light source 22 has deteriorated, and a value calculated as a value at which the division grooves formed in the workpiece 51 can be normally inspected is stored in advance in the storage unit 62. When the luminance of the transmission image 71 is equal to or greater than the threshold value, the control unit 61 diagnoses that the state of the light source 22 is normal. On the other hand, when the luminance of the transmission image 71 is less than the threshold value, the control unit 61 diagnoses that the state of the light source 22 is abnormal. This makes it possible to easily diagnose the deteriorated state of the light source 22.

[0031] In the light source diagnosis method, an adjustment step can be executed after the light source diagnosis step. In the adjustment step, if the luminance of the transmission image 71 acquired in the holding surface imaging step is less than a threshold, the control unit 61 adjusts the current value supplied to the light source 22 so that the luminance of the transmission image 71 becomes equal to or greater than the threshold. Specifically, the control unit 61 increases the current value supplied from a power supply unit (not shown) to the light source 22 to adjust the luminance of the transmission image 71 to be equal to or greater than the threshold.

[0032] When the light source 22 is in a deteriorated state where the brightness of the transmitted image 71 can be adjusted simply by adjusting the value of the current supplied to the light source 22, the light source 22 can be used continuously by simply adjusting the value of the current supplied to the light source 22, thereby reducing the time and parts costs associated with replacing the light source 22.

[0033] On the other hand, in the adjustment step, if the brightness of the transmission image 71 does not become equal to or greater than the threshold value even when the current value supplied to the light source 22 is increased, the control unit 61 diagnoses that the light source 22 is abnormal. That is, even if the current value supplied to the light source 22 is increased to the limit that the light source 22 can tolerate, the division grooves formed in the workpiece 51 cannot be properly inspected, and in this case, the light source 22 is diagnosed as abnormal. This makes it possible to easily diagnose the deterioration state of the light source 22.

[0034] In the light source diagnosis step, the control unit 61 may make a diagnosis based on whether or not a transmission image 71 in which the luminance is continuously less than the threshold value in the X-axis direction is acquired. If a transmission image 71 in which the luminance is continuously less than the threshold value in the X-axis direction is not acquired, the control unit 61 diagnoses that there is no abnormality in the light emitting element 41 constituting the light source 22.

[0035] FIG. 4B is an example of a transmission image 71 acquired when the light-emitting element 41 constituting the light source 22 has an abnormality. As shown in FIG. 4B, in the transmission image 71, a region 81 in which the luminance is less than the threshold value is formed continuously in the X-axis direction. The region 81 is formed continuously along the X-axis direction. Whether the region is continuous or not is determined based on whether a predetermined number of pixels or more are connected. When a predetermined number of pixels or more of pixels in which the luminance is less than the threshold value are connected, the region is determined to be continuous. That is, when a defect occurs in at least one of the light-emitting elements 41 of the light source 22, the luminance along the X-axis direction of the defective light-emitting element 41 becomes dark. Therefore, when a transmission image 71 in which the luminance is less than the threshold value continuously in the X-axis direction is acquired as shown in FIG. 4B, the control unit 61 diagnoses that the light-emitting element 41 constituting the light source 22 has an abnormality. This makes it possible to easily diagnose the deterioration state of the light-emitting element 41 constituting the light source 22.

[0036] In the light source diagnosis step, the control unit 61 may diagnose whether or not a transmission image 71 in which the luminance is discontinuously less than the threshold value in the X-axis direction is acquired. If a transmission image 71 in which the luminance is discontinuously less than the threshold value in the X-axis direction is not acquired, the control unit 61 diagnoses that there is no abnormality in the holding surface 31.

[0037] FIG. 4C is an example of a transmission image 71 acquired when there is an abnormality in the holding surface 31. As shown in FIG. 4C, three regions 82 in which the brightness is less than the threshold value are formed discontinuously in the X-axis direction in the transmission image 71. The regions 82 are formed discontinuously along the X-axis direction. Whether or not they are discontinuous is determined based on whether or not they are formed in a predetermined number of pixels or more. When the pixels in which the brightness is less than the threshold value are connected less than the predetermined number of pixels, it is determined that they are discontinuous. That is, when a foreign object or a scratch is present in a part of the holding surface 31, only the brightness of the corresponding part of the light emitting element 41 becomes dark. Therefore, as shown in FIG. 4C, when a transmission image 71 in which the brightness is less than the threshold value discontinuously in the X-axis direction is acquired, the control unit 61 diagnoses that there is an abnormality in the holding surface 31. This makes it possible to distinguish between the cases of an abnormality in the light source 22 and the state of the light source 22 can be easily diagnosed.

[0038] Furthermore, a state inspection method using the light source diagnosis method may be performed before the holding surface imaging step and the light source diagnosis step of the light source diagnosis method. In the state inspection method, a division groove imaging step and a division determination step are performed.

[0039] The inspection device 1 functions as a device for diagnosing whether the workpiece 51 has been properly divided after the workpiece 51 has been expanded by creating a division starting point. In other words, if the workpiece 51 has been properly divided, the light luminance at the position of the division groove formed along the planned division line (not shown) is increased and an image is taken. Therefore, the inspection device 1 executes a division groove imaging step.

[0040] In the division groove imaging step, as shown in FIG. 1B, the holding table 11 holds the workpiece 51 conveyed by an arm (not shown) or the like vertically above the holding surface 31 (+Z direction). Then, light is irradiated from the light source 22 to the workpiece 51 held on the holding surface 31. A division groove is formed in the workpiece 51 along a division planned line (not shown), and at least a part of the holding surface 31 is formed of a transparent material. Therefore, the light irradiated from the light source 22 to the workpiece 51 held on the holding surface 31 passes through the holding surface 31 and the division groove. The control unit 61 performs imaging of the light transmitted through the holding surface 31 and the division groove by the imaging unit 21 in a plurality of regions while moving the light source 22 and the imaging unit 21 relatively to the holding surface 31 in the X direction. Thereby, as shown in FIG. 5A, a workpiece image 90 transmitted through the holding surface 31 and the division groove can be acquired.

[0041] Workpiece image 90 has groove image 91 including light transmitted through holding surface 31 and the division grooves. Since at least a portion of holding surface 31 is formed of a transparent material and the division grooves of workpiece 51 are formed as gaps, groove image 91 captured by light transmitted through holding surface 31 and the division grooves is formed as semi-transparent lines 92. Since lines 92 are formed along the division grooves of workpiece 51, a plurality of lines are formed along the X-axis and Y-axis directions.

[0042] In the division determination step, the control unit 61 determines whether or not a division groove line 92 can be detected at a position 93 of the planned division line in the groove image 91 acquired in the division groove imaging step. Whether or not a division groove line 92 can be detected at a position 93 of the planned division line can be determined based on whether or not consecutive pixels having a brightness higher than a predetermined value are arranged consecutively at the position 93 corresponding to the planned division line. If a division groove line 92 can be detected at a position 93 of the planned division line in the groove image 91 acquired in the division groove imaging step, the control unit 61 determines that the workpiece 51 has been normally divided.

[0043] Fig. 5A is an example of a groove image 91 acquired when a division groove can be detected at the planned division line position 93. In the groove image 91 acquired when a division groove can be detected at the planned division line position 93, as shown in Fig. 5A, a plurality of lines 92 having continuous uniform brightness are formed along the planned division line position 93 of the workpiece 51 in the X-axis direction and the Y-axis direction of the groove image 91.

[0044] In contrast, if the division groove line 92 cannot be detected at the position 93 of the planned division line in the groove image 91 acquired in the division groove imaging step, the control unit 61 determines that the division of the workpiece 51 is abnormal.

[0045] Fig. 5B is an example of a groove image 91 acquired when a division groove cannot be detected at the position 93 of the planned division line. In the groove image 91 acquired when a division groove cannot be detected at the position 93 of the planned division line, as shown in Fig. 5B, a line 92 formed along the position 93 of the planned division line of the workpiece 51 in the X-axis direction and the Y-axis direction of the groove image 91 is interrupted by a region 94.

[0046] The determination of whether the line 92 is interrupted by the region 94 may be based on whether the line 92 whose brightness is less than the threshold value is continuously acquired in the X-axis or Y-axis direction. If the line 92 whose brightness is less than the threshold value continuously acquired in the X-axis or Y-axis direction is not acquired, the control unit 61 determines that there is no abnormality in the dividing groove of the workpiece 51. If the line 92 whose brightness is less than the threshold value continuously acquired in the X-axis or Y-axis direction is acquired, the control unit 61 determines that there is an abnormality in the dividing groove of the workpiece 51. This makes it easy to diagnose whether the dividing groove of the workpiece 51 is normally formed. In addition, the state inspection method of this embodiment is performed before the holding surface imaging step and the light source diagnosis step. This allows the inspection of the processing state of the workpiece 51 to be performed fully automatically before the actual inspection, thereby simplifying the process.

[0047] In the above-described embodiment, the light source 22 is formed so as to be longer than the diameter of the holding surface 31 along the radial direction (Y-axis direction) of the holding surface 31, but this is not limited thereto. For example, as shown in FIG. 6, the light source 22 may be a ring-shaped light source in which a plurality of light-emitting elements 41 are formed along the outer edge of the holding surface 31 in the circumferential direction. This allows the light source 22 to be fixed, eliminating the need to move the light source 22 and the imaging unit 21 relatively, and simplifying the control. In addition, the inspection device 1 can be configured without being restricted by the shape of the light source 22, and therefore the degree of freedom in the configuration of the inspection device 1 can be increased.

[0048] The embodiments of the present invention are not limited to the above-mentioned embodiments and modifications, and may be modified, substituted, or altered in various ways without departing from the spirit of the technical idea of ​​the present invention. Furthermore, if the technical idea of ​​the present invention can be realized in a different way due to technological progress or a different technology derived therefrom, the present invention may be implemented using that method. Therefore, the claims cover all embodiments that may be included within the scope of the technical idea of ​​the present invention. [Industrial Applicability]

[0049] As described above, the light source diagnosis method using the inspection device 1 of the present invention can easily diagnose the state of the light source. Therefore, it is particularly useful in the field of inspecting the processing state of the workpiece 51 equipped with the light source 22. [Explanation of symbols]

[0050] 1: inspection device, 11: holding table, 21: imaging unit, 22: light source, 31: holding surface, 32: support, 41: light emitting element, 42: imaging element, 51: workpiece, 60: control device, 61: control unit, 62: storage unit

Claims

1. a holding table having a holding surface at least a portion of which is made of a transparent member; A light source disposed on one side of the holding surface; an imaging unit disposed on the other side of the holding surface, In the inspection apparatus, a machining state of a workpiece is inspected, the workpiece being held on the holding table and having a division groove formed along a planned division line, A light source diagnosis method for diagnosing a state of the light source, comprising: Irradiating the holding surface with light from the light source; a holding surface imaging step of imaging light transmitted through the holding surface with the imaging unit; a light source diagnosis step of diagnosing a state of the light source based on the luminance of the image acquired in the holding surface imaging step; A light source diagnosis method comprising:

2. In the light source diagnosis step, If the luminance of the image is less than the threshold, An adjustment step is performed to adjust the current value supplied to the light source so that the luminance of the image is equal to or greater than the threshold value.

2. The light source diagnosis method according to claim 1.

3. In the adjustment step, If the brightness of the image does not exceed the threshold value even when the current value supplied to the light source is increased to a predetermined value, The light source is diagnosed as abnormal.

3. The light source diagnosis method according to claim 2.

4. The holding surface imaging step includes: The light source and the imaging unit facing the light source. The holding surface is moved in the X direction relative to the holding surface in a plurality of regions. The light source has a plurality of light-emitting elements arranged along a Y direction perpendicular to the X direction, The light source diagnosis step includes: When the image is acquired in which the luminance is continuously less than the threshold value in the X direction, The light-emitting element is diagnosed as abnormal, When the image is acquired in which the brightness is discontinuously less than the threshold value in the X direction, The holding surface is diagnosed as abnormal.

4. A light source diagnosis method according to claim 1, wherein the light source diagnosis method is a light source diagnosis method for detecting a light source.

5. A state inspection method for inspecting the processed state of the workpiece using the light source diagnosis method according to any one of claims 1 to 3, comprising: the holding surface imaging step; Prior to the light source diagnosis step, The workpiece is held on the holding surface and the light source is irradiated onto the workpiece, a division groove imaging step of imaging light transmitted through the holding surface and the division groove; a division determination step of determining that the workpiece is divided when the division groove can be detected at the position of the planned division line in the image acquired in the division groove imaging step; A status inspection method comprising the steps of:

Images