Optical inspection device, method for optically inspecting an object to be inspected, and method for optically inspecting the shape of an object to be inspected

Abstract

To provide an optical inspection device that can inspect a change in the state of a specimen such as inclination even if the specimen is sealed inside a container body.SOLUTION: According to an embodiment, an optical inspection device has a container, an image forming optical system, a color filter, and an imaging unit. The container has a container body in which a specimen is contained, and an observation window that has a pair of parallel surfaces passing light from the specimen. The color filter is arranged rotationally symmetrically with respect to an optical axis of the image forming optical system and provided on a focal plane of the image forming optical system. The color filter has a first wavelength selection filter that passes a beam with a first wavelength from the specimen, and a second wavelength selection filter that is formed on an outer periphery of the first wavelength selection filter and passes a beam with a second wavelength from the specimen. The imaging unit is provided on an image forming plane of the image forming optical system, and picks up images of the first wavelength passing through the first wavelength selection filter and the second wavelength passing through the second wavelength selection filter.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] FIELD Embodiments of the present invention relate to an optical inspection apparatus, a method for optically inspecting an object to be inspected, and a method for optically inspecting the shape of an object to be inspected. [Background technology]

[0002] For example, the three-dimensional shape is measured by white light interferometry or laser confocal imaging. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-107118 [Patent Document 2] U.S. Patent No. 3,013,467 Summary of the Invention [Problem to be solved by the invention]

[0004] The problem that the present invention aims to solve is to provide an optical inspection device, an optical inspection method for an object to be inspected, and an optical inspection method for the shape of an object to be inspected, which are capable of inspecting changes in the state of the object to be inspected, such as the inclination, even when the object to be inspected is sealed inside the container body. [Means for solving the problem]

[0005] According to an embodiment, the optical inspection device includes a container, an imaging optical system, a color filter, and an imaging unit. The container includes a container body in which a test object is accommodated and an observation window that separates the inside and outside of the container body and has a pair of parallel surfaces through which light from the test object passes. The imaging optical system forms an image of light from the test object that passes through the observation window. The color filter is disposed rotationally symmetrically with respect to the optical axis of the imaging optical system and is provided on the focal plane of the imaging optical system. The color filter includes a disk-shaped or annular first wavelength-selective filter that is provided on the optical axis of the imaging optical system and passes through the imaging optical system to pass light of a first wavelength from the test object, and a second wavelength-selective filter that is annularly formed on the outer periphery of the first wavelength-selective filter and passes through the imaging optical system to pass light of a second wavelength from the test object that is different from the first wavelength. The imaging unit is provided on the imaging plane of the imaging optical system, and captures an image of a light beam of a first wavelength that has passed through the first wavelength selection filter and a light beam of a second wavelength that has passed through the second wavelength selection filter. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic block diagram showing an optical inspection system according to first and second embodiments. [Figure 2] 1 is a schematic diagram showing the arrangement of a camera, a light source, and a container in an optical inspection system according to a first embodiment. [Figure 3] 3 is a schematic diagram showing the relationship between the camera of the optical inspection system shown in FIG. 2 and the object to be inspected inside the container body. [Figure 4] FIG. 4 is a schematic diagram showing color filters of the camera shown in FIGS. 2 and 3. [Figure 5] 3 is a schematic diagram illustrating the relationship between an observation window of the container shown in FIG. 2 and the incident and outgoing directions of light. FIG. [Figure 6] 3A to 3C are schematic diagrams showing an RGB image, an R image, a B image, and a G image when an object to be inspected is imaged by an imaging unit of a camera in the optical inspection system according to the first embodiment. [Figure 7] 7 is a schematic cross-sectional view taken along line VII-VII in FIG. 6 when the test object shown as an RGB image in FIG. 6 is considered to be the actual test object. [Figure 8]10 is a flowchart showing an example of processing for outputting a scattering angle at an object point on a test object based on the color of a light beam captured by an imaging unit using the optical inspection system according to the first embodiment. [Figure 9] FIG. 3 is a schematic diagram showing a state of light emission from a heater used in a container heating unit of the optical inspection system according to the first embodiment. [Figure 10] 5A to 5C are schematic diagrams showing RGB images, an R image, a B image, and a G image when a heated test object is imaged by the imaging unit of the camera of the optical inspection system according to the first embodiment. [Figure 11] 11 is a schematic cross-sectional view taken along line XI-XI in FIG. 10 when the test object shown as an RGB image in FIG. 10 is considered to be the actual test object. [Figure 12] 5A to 5C are schematic diagrams showing RGB images, an R image, a B image, and a G image when a heated test object is imaged by the imaging unit of the camera of the optical inspection system according to the first embodiment. [Figure 13] 13 is a schematic cross-sectional view taken along line XIII-XIII in FIG. 12 when the test object shown as an RGB image in FIG. 12 is considered to be the actual test object. [Figure 14] FIG. 10 is a schematic block diagram showing an optical inspection system according to a modified example of the first embodiment. [Figure 15] FIG. 10 is a schematic diagram showing the relationship between a camera of an optical inspection system according to a modified example of the first embodiment and an object to be inspected inside a container body. [Figure 16] 16 is a schematic diagram showing a first color filter disposed on the focal plane of the imaging optical system of the camera shown in FIG. 15. [Figure 17] 16 is a schematic diagram illustrating a second color filter disposed adjacent to the imaging optics of the camera shown in FIG. 15. [Figure 18] 10 is a flowchart showing an example of processing for detecting the three-dimensional position of an object point on a test object using an optical inspection system according to a modified example of the first embodiment. [Figure 19] FIG. 10 is a schematic diagram showing the arrangement of a camera, a light source, and a container in an optical inspection system according to a second embodiment. [Figure 20]This is a schematic diagram of the solder material and surface-mounted components on a Cu substrate when the test object is heated, viewed from the side of the optical axis. [Figure 21] 21A and 21B are schematic diagrams showing an RGB image, an R image, a B image, and a G image when the test object is imaged by the imaging unit of the camera of the optical inspection system according to the second embodiment, with the test object in the state shown in FIG. 20. [Figure 22] This is a schematic diagram of the solder material and surface-mounted components on a Cu substrate when the test object is heated, viewed from the side of the optical axis. [Figure 23] 23 is a schematic diagram showing an RGB image, an R image, a B image, and a G image when the test object is imaged by the imaging unit of the camera of the optical inspection system according to the second embodiment, with the test object in the state shown in FIG. 22. [Figure 24] This is a schematic diagram of the solder material and surface-mounted components on a Cu substrate when the test object is heated, viewed from the side of the optical axis. [Figure 25] 25 is a schematic diagram showing an RGB image, an R image, a B image, and a G image when the test object is imaged by the imaging unit of the camera of the optical inspection system according to the second embodiment, with the test object in the state shown in FIG. 24. DETAILED DESCRIPTION OF THE INVENTION

[0007] Each embodiment will be described below with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc., are not necessarily the same as those in reality. Furthermore, even when the same part is shown, the dimensions and ratios may be different depending on the drawing. In this specification and each drawing, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions will be omitted as appropriate.

[0008] (First embodiment) An optical inspection system 2 according to this embodiment will be described with reference to FIGS.

[0009] 1 is a block diagram showing an example of the configuration of an optical inspection system 2 according to this embodiment. As shown in FIG. 1, the optical inspection system 2 includes an optical inspection device 4 and a display 6.

[0010] The optical inspection device 4 includes an optical device 12, an imaging unit 14, a container 16, a light source 18, a processing circuit 20, and a memory 22. The optical device 12 and the imaging unit 14 constitute a so-called camera 13.

[0011] As shown in FIG. 2, the optical device 12 includes an imaging optical system (imaging lens) 32 and a color filter (color aperture) .

[0012] The imaging optical system 32 is formed by combining one or more lenses. The imaging optical system 32 forms an image of light rays from the object to be measured. The optical axis C of the imaging optical system 32 coincides with the optical axis (central axis) of the color filter 34. The color filter 34 is disposed on a focal plane at a distance f from the imaging optical system 32, and rotationally symmetric with respect to the optical axis of the imaging optical system 32. The image capturing unit 14 is disposed on the optical path of light passing through the imaging optical system 32 and the color filter 34. The image capturing unit 14 is provided on the imaging plane at a distance L (>f) from the imaging optical system 32.

[0013] Fig. 3 is an enlarged view of a part of the optical device 12 and the imaging unit 14 shown in Fig. 2. As shown in Fig. 3, for example, a light ray L11 specularly reflected at an object point O on the test object S and light rays L21 and L31 scattered at appropriate angles are refracted by the imaging optical system 32, and light rays L12, L22, and L32 are imaged on the imaging surface 14a of the imaging unit 14.

[0014] 4, the color filter 34 has a first wavelength-selective filter (wavelength-selective region) 42, a second wavelength-selective filter (wavelength-selective region) 44, and a third wavelength-selective filter (wavelength-selective region) 46. The first wavelength-selective filter 42, the second wavelength-selective filter 44, and the third wavelength-selective filter 46 are formed concentrically. The color filter 34 has the property of transmitting light rays of specific wavelengths (wavelength spectrum) for each of the wavelength-selective filters 42, 44, and 46, and blocking light rays of wavelengths outside the specific wavelengths.

[0015] The first wavelength-selective filter 42 is formed in a disk shape. The first wavelength-selective filter 42 is provided on the optical axis C of the imaging optical system 32. The first wavelength-selective filter 42 passes light rays of a first wavelength from the test object that have passed through the imaging optical system 32. The first wavelength-selective filter 42 has the property of blocking light rays of wavelengths different from the first wavelength (specific wavelength) rather than transmitting them.

[0016] The second wavelength-selecting filter 44 is formed in an annular shape on the outer periphery of the first wavelength-selecting filter 42. The second wavelength-selecting filter 44 passes light rays of a second wavelength, which is different from the first wavelength and which has passed through the imaging optical system 32 and is emitted from the test object. The radial width of the second wavelength-selecting filter 44 can be set appropriately. The second wavelength-selecting filter 44 has the property of blocking light rays of a wavelength different from the second wavelength (specific wavelength) and not transmitting them.

[0017] The third wavelength-selecting filter 46 is formed in an annular shape on the outer periphery of the second wavelength-selecting filter 44. The third wavelength-selecting filter 46 passes light rays of a third wavelength, which is different from the first wavelength and the second wavelength and which has passed through the imaging optical system 32 and is from the test object. The radial width of the third wavelength-selecting filter 46 can be set appropriately. The third wavelength-selecting filter 46 has the property of blocking light rays of wavelengths different from the third wavelength (specific wavelength) and not transmitting them.

[0018] The color filter 34 has a light-shielding portion 48 on the outer periphery of the third wavelength-selective filter 46. The light-shielding portion 48 is formed of, for example, a black plate and holds the third wavelength-selective filter 46. The third wavelength-selective filter 46 holds the second wavelength-selective filter 44. The second wavelength-selective filter 44 holds the first wavelength-selective filter 42. The color filter 34 may be configured so that the wavelength of light that it transmits changes continuously, for example, from the inside to the outside. That is, the color filter 34 is configured to transmit light of the same wavelength in a circular shape from the inside to the outside around a common central axis, but not to transmit light of different wavelengths.

[0019] The radius of the outer periphery of the first wavelength-selective filter 42 of the color filter 34 is r1, the radius of the outer periphery of the second wavelength-selective filter 44 is r2, and the outer radius of the third wavelength-selective filter 46 is r3. In this case, r3>r2>r1. Here, the area within the radius r1 of the first wavelength-selective filter 42 is A1. The area between the outer periphery of the first wavelength-selective filter 42 and the outer periphery of the second wavelength-selective filter 44 is A2. The area between the outer periphery of the second wavelength-selective filter 44 and the outer periphery of the third wavelength-selective filter 46 is A3.

[0020] The radius r1 of the first wavelength-selective filter 42, the distance r2-r1 between the outer periphery of the first wavelength-selective filter 42 and the outer periphery of the second wavelength-selective filter 44, and the distance r3-r2 between the outer periphery of the second wavelength-selective filter 44 and the outer periphery of the third wavelength-selective filter 46 can be set appropriately. More specifically, the radius r1 of the first wavelength-selective filter 42 of the color filter 34, the radius r2 of the second wavelength-selective filter 44, and the radius r3 of the third wavelength-selective filter 46 can be changed depending on the detection object. Therefore, the shapes and sizes of the regions A1, A2, and A3 can change depending on the detection object.

[0021] In the optical device 12 according to this embodiment, among the light rays emitted from an arbitrary object point O of the test object S, red (R) light whose chief ray is parallel to the optical axis C when it enters the imaging optical system 32 is separated as a red light ray. In other words, the optical device 12 according to this embodiment is a telecentric optical system that is telecentric with respect to the red light ray. On the other hand, the optical device 12 according to this embodiment is a non-telecentric optical system that is not telecentric with respect to the blue (B) light and green (G) light.

[0022] In this embodiment, the optical inspection system 2, which will be described later, is used to detect contact angles α and β between a substrate S1 and an object (a brazing filler metal as a molten material (liquid)) S2 placed on the substrate S1 and evaluate wettability. The contact angles α and β depend on, for example, the properties and temperature of the material. When the contact angles α and β are small, the contact angles α and β are estimated to be in a range of less than 10°. As an example, in this embodiment, the color filter 34 has a first wavelength-selective filter 42 whose r1 is determined so that the angle of the scattered light with respect to the optical axis C (scattering angle θ) can be obtained in a range of, for example, 0° to 3°. The color filter 34 has a second wavelength-selective filter 44 whose radius r2 is determined so that the angle of the scattered light with respect to the optical axis C (scattering angle θ) can be obtained in a range of, for example, 3° to 6°. In the color filter 34, the radius r3 of the third wavelength selection filter 46 is defined so that the angle of the scattered light with respect to the optical axis C (scattering angle θ) can be in the range of, for example, 6° to 9°.

[0023] Light is a type of electromagnetic wave, and includes X-rays, ultraviolet light, visible light, infrared light, microwaves, and the like. In this embodiment, the light is assumed to be visible light, with a wavelength in the range of 400 nm to 760 nm, for example. For the sake of simplicity, in this embodiment, the color filter 34 is assumed to transmit light of a certain wavelength among visible light, and block wavelengths outside of the certain wavelength range, i.e., prevent transmission thereof, for each of the wavelength selection filters 42, 44, and 46.

[0024] In this embodiment, for convenience, the wavelengths of red light, green light, and blue light are set to 700 nm, 546.1 nm, and 435.8 nm, respectively, as determined by the International Commission on Illumination (CIE).

[0025] In this embodiment, the region A1 of the first wavelength-selective filter 42 passes visible light, for example, red light (700 nm) and R light having a first wavelength nearby red light, and blocks light of other wavelengths. In this embodiment, the region A2 of the second wavelength-selective filter 44 passes visible light, for example, blue light (435.8 nm) and B light having a second wavelength nearby blue light, and blocks light of other wavelengths. In this embodiment, the region A3 of the third wavelength-selective filter 46 passes visible light, for example, green light (546.1 nm) and G light having a third wavelength nearby green light, and blocks light of other wavelengths. In this embodiment, it is preferable that the first wavelength range passed by the region A1 of the first wavelength-selective filter 42, the second wavelength range passed by the region A2 of the second wavelength-selective filter 44, and the third wavelength range passed by the region A3 of the third wavelength-selective filter 46 do not overlap.

[0026] The optical device 12 has a half mirror 36. The half mirror 36 is provided between the imaging optical system 32 and the container 16. The half mirror 36 illuminates the specimen S in the container 16 with illumination light (white light) from the light source 18, and transmits light from the specimen S to make it incident on the imaging optical system 32.

[0027] The imaging unit 14 may be, for example, a so-called RGB camera, or may be, for example, a CMOS image sensor or a CCD image sensor.

[0028] As shown in Figure 3, the imaging unit 14 images a light ray L12 of a first wavelength that has passed through the imaging optical system 32 and the area A1 of the first wavelength selection filter 42, a light ray L22 of a second wavelength that has passed through the imaging optical system 32 and the area A2 of the second wavelength selection filter 44, and a light ray L32 of a third wavelength that has passed through the imaging optical system 32 and the area A3 of the third wavelength selection filter 46.

[0029] As shown in FIG. 2, the container 16 includes a container body 62 in which the specimen S is housed, an observation window 64, and a stage 66 on which the specimen S is placed.

[0030] The container body 62 is formed, for example, from a non-translucent material. It is preferable that the container body 62 has heat insulating properties that prevent heat from being transferred to the outside when the inside is heated. It is also preferable that the container body 62 has rigidity that allows it to maintain its shape when it is evacuated and the internal pressure inside the container body 62 is appropriately reduced. It is also preferable that the container body 62 has rigidity that allows it to maintain its shape when a gas is introduced and the internal pressure inside the container body 62 is appropriately increased.

[0031] The container body 62 has an opening edge 62a through which the specimen S is put into and taken out of the container body 62. The opening edge 62a is formed, for example, on the upper surface of the container body 62 in the shape of, for example, a ring.

[0032] The opening edge 62a allows observation of the specimen S on the stage 66 from outside the container body 62. The opening diameter of the opening edge 62a is, for example, about 150 mm. The distance from the opening edge 62a to the stage 66 is, for example, about 500 mm.

[0033] The observation window 64 is detachably fixed to the opening edge 62a of the container body 62. For example, a glass plate is used for the observation window 64. The observation window 64 is preferably formed so that deformation thereof is negligible when the internal pressure in the container body 62 is appropriately increased or decreased.

[0034] It is preferable that the inside of the container body 62 is sealed when the observation window 64 is attached to the opening edge 62a of the container body 62. Therefore, when attached to the container body 62, the observation window 64 separates the inside and outside of the container body 62.

[0035] As shown in FIG. 5, the observation window 64 has a pair of parallel surfaces 64a and 64b. When light is incident from the outside of the container body 62 to the test object S inside, the incident angle θ11 of the incident light on the parallel surface 64a facing the outside of the container body 62 is parallel to the exit angle θ12 of the light passing through the parallel surface 64b facing the inside of the container body 62. When light is reflected by the test object S in the container body 62 and exits from the inside of the container body 62 to the outside, the incident angle θ21 of the exit light on the inner parallel surface 64b is parallel to the exit angle θ22 of the light passing through the outer parallel surface 64a. Therefore, the normal direction of the pair of parallel surfaces 64a and 64b of the observation window 64 does not need to coincide with the incident direction of the light ray.

[0036] 2, the stage 66 is provided inside the container body 62. In this embodiment, the stage 66 is disposed directly below an observation window 64 on the top surface of the container body 62. The optical device 12 is disposed above the observation window 64. A half mirror 36 is disposed between the imaging optical system 32 of the optical device 12 and the observation window 64. The half mirror 36 reflects light from the light source 18 and illuminates the test object S on the stage 66 through the observation window 64, and also causes the reflected light that illuminates the test object S and passes through the observation window 64 to enter the imaging optical system 32 of the optical device 12 through the half mirror 36.

[0037] Therefore, in this embodiment, the container 16, the optical device 12, and the imaging unit 14 are arranged apart from each other in the vertical direction.

[0038] The container 16 has a heating unit 72 for heating the specimen S, a temperature detection unit 74, a vacuum device 76, and a pressure detection unit 78.

[0039] The heating unit 72 has, for example, a coil 72a that covers the outer periphery of the stage 66. The stage 66 is formed of a conductive material such as carbon. Therefore, when a high-frequency current is applied to the coil 72a, the stage 66 is heated. By applying a high-frequency current to the coil 72a, the heating unit 72 heats the stage 66 and the specimen S placed on the stage 66 by thermal conduction.

[0040] The container body 62 , the stage 66 , and the observation window 64 are made of a heat-resistant material that is prevented from being deformed or melted by the heat of the heating unit 72 .

[0041] The temperature detection unit 74 detects the temperature inside the container body 62 heated by the heating unit 72. The temperature detection unit 74 measures the temperature inside the container body 62 using, for example, a thermocouple or the like.

[0042] The vacuum device 76 has a turbomolecular pump 76a and a rotary pump 76b. These turbomolecular pump 76a and rotary pump 76b exhaust gas from the vessel body 62 and attempt to create a vacuum inside the vessel body 62. In this embodiment, the pressure inside the vessel body 62 is reduced to, for example, 10 -3 It is possible to reduce the pressure to about 100 Pa. Regarding the pressure reducing device, any device can be selected, such as an oil diffusion pump, a cryopump, a mechanical booster pump, or a diaphragm pump.

[0043] The pressure detection unit 78 detects the pressure inside the container body 62 .

[0044] In this embodiment, a substrate S1 and a brazing filler metal S2 placed on the substrate S1 are used as the test object S. The substrate S1 is formed into an appropriate shape, such as a disk or a rectangle. If the substrate S1 is disk-shaped, the diameter of the substrate S1 is formed to be, for example, several times larger than the size of the brazing filler metal S2. The diameter of the brazing filler metal S2 in a solid state is, for example, about 10 mm.

[0045] The substrate S1 is, for example, a Cu plate. In this embodiment, a brazing filler metal S2 that can be molten, such as an Ag-Cu alloy material called silver brazing filler metal, is placed on a horizontal plane S11 of the substrate S1. The melting point of the substrate S1 is higher than that of the brazing filler metal S2 as a molten material. The heating unit 72 heats the test object S to a temperature higher than that of the brazing filler metal S2 as a molten material and lower than that of the substrate S1.

[0046] As for the heating device for heating the brazing material S2 on the base material S1 placed on the stage 66, any heating device can be selected, such as electromagnetic induction heating, radiation heating, resistance heating, laser heating, and the like.

[0047] As an example, a light source that emits white light of appropriate brightness is used as the light source 18. Therefore, the illumination light of the light source 18 includes red (R) light, green (G) light, and blue (B) light.

[0048] The processing circuit 20 shown in FIG. 1 includes a processor. The processing circuit 20 is, for example, an integrated circuit such as a central processing unit (CPU) or an application specific integrated circuit (ASIC). A general-purpose computer may be used as the processing circuit 20. The processing circuit 20 is not limited to being provided as a dedicated circuit, but may also be provided as a program executed by a computer. In this case, the program is recorded in a storage area within the integrated circuit, a memory 22, or the like. The processing circuit 20 is connected to the imaging unit 14 and the memory 22. The processing circuit 20 calculates information related to the test object S based on the output of the imaging unit 14.

[0049] As shown in FIG. 1, the processing circuit (first processor) 20 has the functions of a color extraction unit 81 and a scattering angle calculation unit .

[0050] The color extraction unit 81 is an example of a generation unit. Based on the output of the imaging unit 14, the color extraction unit 81 outputs the intensities of R light, B light, and G light of the light rays that reach the imaging surface for each pixel of the imaging unit 14. The color extraction unit 81 separates the image data output by the imaging unit 14 into R, G, and B colors to generate image data for each color. The color extraction unit 81 is an example of a generation unit. Note that extracting colors by the color extraction unit 81 includes dividing an RGB image captured by the imaging unit 14 into color channels, or directly acquiring a red (R) light image (R image), a green (G) light image (G image), and a blue (B) light image (B image), i.e., the R, G, and B color channels, from the imaging unit 14.

[0051] The scattering angle calculation unit 82 calculates information related to the object point O of the test object S based on the image data of the R image (first image), the G image (second image), and the B image (second image). Specifically, the scattering angle calculation unit 82 identifies the color of the captured light beam based on the image data of the R image, the G image, and the B image. The scattering angle calculation unit 82 calculates the scattering angle of the ambient light at the object point O of the test object S based on the color of the captured light beam, i.e., the intensities of the R light, the G light, and the B light of the light beam that reached the imaging surface 14a. The scattering angle calculation unit 82 is an example of a calculation unit. The scattering angle at the object point O of the test object S is an example of information related to the test object S.

[0052] The processing circuit 20 may be located outside the optical inspection device 4. In this case, the output of the imaging unit 14 may be output to the outside of the optical inspection device 4 or recorded in the memory 22. In other words, the calculation of information related to the test object S may be performed inside or outside the optical inspection device 4.

[0053] The memory 22 is a non-volatile memory such as a flash memory, but may also include a volatile memory.

[0054] The memory 22 stores the outputs of the imaging unit 14 and the processing circuit 20. The memory 22 stores the focal length f of the imaging optical system 32, the distance L between the imaging optical system 32 and the imaging surface 14a of the imaging unit 14, the arrangement of the multiple wavelength selection filters 42, 44, 46 of the color filter 34, and the like.

[0055] The memory 22 pre-records the relationship between the channel from which an image is obtained and the scattering angle θ, and the relationship between the scattering angle θ and the inclination of the test object S (here, the contact angle). In the example of this embodiment, for simplicity of explanation, the scattering angle θ and the contact angle are described as having a one-to-one correspondence (scattering angle θ = contact angle). However, the relationship between the scattering angle θ and the contact angle can be determined by measuring the relationship before the experiment and multiplying the scattering angle θ by an appropriate coefficient (not limited to a natural number). As an example, the scattering angle θ may be twice the contact angle.

[0056] Therefore, the radii r1, r2, and r3 of the color filter 34 relative to the optical axis C are set based on the relationship between the scattering angle θ and the contact angle.

[0057] The display 6 displays the output of the processing circuit 20. The output of the processing circuit 20 includes, for example, an image based on the image data output by the imaging unit 14, an operation screen, etc. The display 6 is, for example, a liquid crystal display or an organic EL display. Note that the display 6 does not necessarily have to be provided. In this case, the output of the processing circuit 20 may be recorded in the memory 22, displayed on a display provided outside the optical inspection system 2, or recorded in a memory provided outside the optical inspection system 2.

[0058] Using the optical inspection device 4 according to this embodiment, a test was conducted to measure the contact angle of the brazing material S2 with respect to the flat surface S11 of the substrate S1 when the brazing material S2 was melted and liquefied by heating the inside of the container 16, and a test was also conducted to detect the shape of the brazing material S2 with respect to the substrate S1.

[0059] Here, the incident position of the specularly reflected light component from the test object S on the imaging surface 14a and the wavelength that can pass through the color filter 34 do not depend on the distance from the test object S. This is because, in this embodiment, the image that passes through the imaging optical system 32 as parallel light with respect to the optical axis C is captured as an R image by the color filter 34. The R image does not depend on the distance from the test object S.

[0060] On the other hand, the incident position on the imaging surface 14a of the scattered light component from the test object S and the wavelength that can pass through the color filter 34 change depending on the distance from the test object S. For example, even if the scattering angle θ is small, if the distance from the camera 13 is long, the light with that scattering angle θ will head toward a position outside the imaging optical system 32. In this case, an image with that scattering angle cannot be obtained.

[0061] For this reason, the relationship between the scattering angle θ and the contact angle is adjusted by adjusting the positional relationship (distance) between the test object S and the camera 13. Note that the relationship between the scattering angle θ and the contact angle depending on the positional relationship (distance) between the test object S and the camera 13 can be obtained in advance by experiment.

[0062] As described above, in the example of this embodiment, for the sake of simplicity, the positional relationship between the test object S and the camera 13 is adjusted so that the scattering angle θ and the contact angle have a one-to-one correspondence (scattering angle θ=contact angle). Then, the processing circuitry 20 stores the relationship between the scattering angle θ and the contact angle in the memory 22.

[0063] As shown in FIG. 2, a substrate S1 and 0.2 g of brazing filler metal S2 were placed on a stage 66 directly below an observation window 64 of a container 16. Illumination light from a light source 18 was irradiated onto the test object S (the substrate S1 and the brazing filler metal S2 on the substrate S1) through a half mirror 36 and the observation window 64, and reflected light from the test object S was acquired by a camera 13 through the observation window 64 and the half mirror 36. Here, an image (RGB image) of the substrate S1 and the brazing filler metal S2 on the substrate S1 was acquired by the camera 13 through the observation window 64 supported by a container body 62, and the RGB image shown in FIG. 6 and / or a red light image (R image), a blue light image (B image), and a green light image (G image) were displayed on the display 6. Note that when the test object S shown as an RGB image in FIG. 6 is considered to be the actual object, it is assumed that the cross section of the test object S at a position along line VII-VII in FIG. 6 is formed approximately as shown in FIG. 7.

[0064] Here, the operation of the processing circuit 20 will be described with reference to Fig. 8. Fig. 8 is a flowchart showing an example of calculation processing according to this embodiment. In the calculation processing, the processing circuit 20 calculates information related to an object point O on the test object S based on the output of the imaging unit 14.

[0065] In step ST11, the processing circuit 20 functioning as the color extraction unit 81 acquires the intensity of each of the R, G, and B rays of light that are emitted from an arbitrary object point O and incident on the imaging surface 14a, based on the output of the imaging unit 14. As a result, the image data is color-separated into an R image, a B image, and a G image.

[0066] In step ST12, the processing circuit 20 functioning as the color extraction unit 81 identifies the color (hue) of a ray of light that is emitted from an arbitrary object point O and is incident on the imaging surface 14a.

[0067] In step ST13, the processing circuit 20 serving as the scattering angle calculation unit 82 calculates the scattering angle θ of the ambient light at the object point O based on the identified color of the light ray. Here, in the optical device 12 according to this embodiment, the multiple wavelength-selective filters 42, 44, 46 of the color filter 34 are arranged concentrically. That is, in the optical device 12, each of the regions A1, A2, A3 of the multiple wavelength-selective filters 42, 44, 46 of the color filter 34 is rotationally symmetric about the optical axis C of the imaging optical system 32. Therefore, the light ray is color-separated according to the scattering angle θ at an arbitrary object point O. Therefore, a red light image (R image), a blue light image (B image), and a green light image (G image) are spectrally separated according to the scattering angle θ at the object point (surface) O of the object S.

[0068] When the color of the identified light ray is red (R light), the processing circuit 20 as the scattering angle calculation unit 82 calculates that the scattering angle θ at the object point O is 0≦θ<θr. In this case, θ is, for example, equal to or greater than 0° and less than 3°. When the color of the identified light ray is blue (B light), the processing circuit 20 as the scattering angle calculation unit 82 calculates that the scattering angle θ at the object point O is θr≦θ<θb. In this case, θ is, for example, equal to or greater than 3° and less than 6°. When the color of the identified light ray is green (G light), the processing circuit 20 as the scattering angle calculation unit 82 calculates that the scattering angle θ at the object point O is θb≦θ<θg. In this case, θ is, for example, equal to or greater than 6° and less than 9°.

[0069] In this way, the processing circuit 20 of the optical inspection system 2 according to this embodiment can output the scattering angle θ at the object point O based on the color of the captured light beam.

[0070] In this embodiment, the correspondence between the scattering angle θ and the contact angle is stored in advance in the memory 22. Here, there is a one-to-one correspondence between the scattering angle θ and the contact angle. That is, the color filter 34 is disposed with respect to the test object S so that the scattering angle θ=the contact angle. Therefore, the processing circuit 20 can obtain the contact angle corresponding to the scattering angle θ by calculating the scattering angle θ.

[0071] The container 16 shown in Fig. 2 has an observation window 64 that can transmit light rays generated by the light source 18 to irradiate the test object S and can transmit reflected light from the test object S. The normal direction of this observation window 64 does not need to coincide with the incident direction of the light rays. This is due to the characteristic that the direction of the light rays incident on the observation window 64 does not change before and after passing through the object, as shown in Fig. 5. For this reason, even in a heating furnace in which the parallel surfaces 64a and 64b of the observation window 64 are inclined with respect to the optical axis of the optical device 12, an image of the test object S can be obtained through the observation window 64 according to this embodiment.

[0072] In the container body 62 and observation window 64 shown in FIG. 2, the angle of incidence at which white light from the light source 18 is incident on the observation window 64 and the angle of emission from the observation window 64 toward the substrate S1 and the brazing filler metal S2 do not change, regardless of temperature changes due to heating by the heating unit 72. Alternatively, the change in the angle of incidence and the angle of emission is negligibly small. Furthermore, the angle of incidence at which reflected light from the substrate S1 and the brazing filler metal S2 is incident on the observation window 64 and the angle of emission from the observation window 64 toward the optical device 12 do not change. Alternatively, the change in the angle of incidence and the angle of emission is negligibly small. Therefore, even in a container 16 used as a heating furnace, by having the container body 62 and observation window 64 according to this embodiment, it is possible to obtain images of changes in the state of the substrate S1 and the brazing filler metal S2 of the test object S using the optical device 12.

[0073] In this embodiment, the optical axis C of the optical device 12 is adjusted so that light from the plane S11 of the substrate S1 on which the brazing material S2 is placed, based on the illumination light from the light source 18, passes through the center of the color filter 34. That is, the plane S11 of the substrate S1 is perpendicular to the optical axis C. At this time, the camera 13 obtains the RGB image shown in FIG. 6. Furthermore, the color extraction unit 81 of the processing circuit 20 obtains a red light image (R image), a blue light image (B image), and a green light image (G image). In the B image and the G image, the plane S11 of the substrate S1 is obtained as a black image. In the R image, the shape of the plane S11 of the substrate S1 is obtained as a bright color. Note that when the scattered light from the brazing material S2 is incident on any one of the first wavelength-selective filter 42, the second wavelength-selective filter 44, and the third wavelength-selective filter 46 of the color filter 34, the R image, the B image, and the G image are added together to form an RGB image. In this embodiment, part of the scattered light from the brazing material S2 is incident on the light shielding portion 48 of the color filter 34. Therefore, there may be some portions of the brazing material S2 that cannot be imaged by the imaging unit 14.

[0074] The specularly reflected light component (bright area) of the brazing material S2 can be obtained as part of the R image, along with the flat surface S11 of the substrate S1. In the R image, the scattered light component of the brazing material S2 that is not the specularly reflected light component appears as a black image (black area). The scattered light is obtained as a B image and / or a G image depending on the scattering angle. In the B image, the specularly reflected light component of the brazing material S2 appears as a black image. In the B image, the portion of the brazing material S2 obtained as the G image appears as a black image. In the G image, the specularly reflected light component of the brazing material S2 appears as a black image. In the G image, the portion of the brazing material S2 obtained as the B image appears as a black image.

[0075] After the operator checks the display 6 to see that the plane S11 of the substrate S is displayed as a bright area in the R image, the operator uses the vacuum device 76 to evacuate the inside of the container body 62. When the pressure detector 78 detects the pressure inside the container body 62, the operator checks that the degree of vacuum is, for example, 10 -3 Wait until the temperature drops below Pa.

[0076] As a result of detection by the pressure detection unit 78, the degree of vacuum in the container body 62 is 10 -3 After the pressure drops below Pa, the worker applies a high-frequency current to the induction heating coil 72a of the heating section 72 to heat the stage 66, and starts measuring the angle information of the contact angle between the base material S1 and the brazing material S2 using the optical inspection device 4 based on the image captured by the camera 13.

[0077] As long as the temperature inside the container body 62 is within a temperature sufficient to melt the brazing filler metal S2, for example, the container body 62 and the observation window 64 maintain the parallel and unchanging relationship between the incident angle at which white light from the light source 18 is incident on the observation window 64 and the exit angle from the observation window 64 toward the substrate S1 and the brazing filler metal S2, regardless of the degree of vacuum. Alternatively, the change in the incident angle and the exit angle is negligibly small, and the incident angle and the exit angle can be considered to be parallel. Furthermore, the incident angle at which reflected light from the substrate S1 and the brazing filler metal S2 is incident on the observation window 64 and the exit angle from the observation window 64 toward the optical device 12 maintain the parallel and unchanging relationship. Alternatively, the change in the incident angle and the exit angle is negligibly small, and the incident angle and the exit angle can be considered to be parallel. Therefore, even in a container 16 used as a heating vacuum furnace, the container body 62 and the observation window 64 according to this embodiment allow the camera 13 to obtain images of changes in the state of the substrate S1 and the brazing filler metal S2 of the test object S.

[0078] For example, the temperature inside the container body 62 is measured by the temperature detection unit (thermocouple) 74. The worker confirms that the brazing material S2 on the flat surface S11 of the base material S1 has reached the melting point (780° C. in this example).

[0079] In the light source 18 according to this embodiment, the intensity of light irradiated onto the test object S is greater than the intensity of light emitted by the coil 72a of the heating unit 72 due to heat generation. When the coil 72a is heated to, for example, 780°C, the coil 72a emits red light. As shown in FIG. 9 , the peak wavelength of the light emitted by the coil 72a at this time is longer than that of red light (700 nm), for example, approximately 3000 nm, and is in the infrared region. As described above, the first wavelength-selective filter 42 of the color filter 34 passes red light but blocks light of other wavelengths. The second wavelength-selective filter 44 passes blue light but blocks light of other wavelengths. The third wavelength-selective filter 46 passes green light but blocks light of other wavelengths. Therefore, the wavelength-selective filters 42, 44, and 46 of the color filter 34 are configured to block the peak wavelength (for example, 3000 nm) of light emitted from the heating unit 72 when the heating unit 72 is heated. For this reason, in this embodiment, most of the wavelengths of light generated by the heat generated by the heating unit 72 do not pass through the color filter 34. Therefore, when capturing an image of the subject S, the imaging unit 14 is prevented from being affected by the light emitted by the heating unit 72.

[0080] As the brazing filler metal S2 on the flat surface S11 of the base material S1 melts, the contact angle gradually decreases from a large state. The contact angle α or β at the point when the brazing filler metal S2 on the flat surface S11 of the base material S1 melts and the expansion of the droplet on the flat surface S11 of the base material S1 stops is defined as the final contact angle.

[0081] 10 to 13, in this embodiment, the contact angle of the brazing filler metal S2 with respect to the flat surface S11 of the base material S1 is an acute angle. Depending on the magnitude of the contact angle, the position at which the reflected light (scattered light) from the brazing filler metal S2 enters the imaging optical system 32 changes, and the image captured by the imaging unit 14 through the color filter 34 also changes.

[0082] FIG. 10 shows an example of an RGB image and / or an R image, a B image, and a G image when the scattering angle θ (contact angle) is an angle α (>β). When the test object S shown as the RGB image in FIG. 10 is considered to be the actual object, it is assumed that the cross section of the test object S along the line XI-XI in FIG. 10 is formed approximately as shown in FIG. 11. FIG. 12 shows an example of an RGB image and / or an R image, a B image, and a G image when the scattering angle θ (contact angle) is an angle β (<α). When the test object S shown as the RGB image in FIG. 13 is considered to be the actual object, it is assumed that the cross section of the test object S along the line XIII-XIII in FIG. 12 is formed approximately as shown in FIG. 13.

[0083] As shown in Fig. 11, when the contact angle α is larger than the contact angle β shown in Fig. 13, when the image captured by the imaging unit 14 is divided into an R image, a B image, and a G image as shown in Fig. 10, the brazing filler metal S2 is obtained as an R image captured through the first wavelength-selecting filter 42 at the center, and a G image captured through the third wavelength-selecting filter 46. Note that there are cases where the brazing filler metal S2 portion is not obtained as an R image, but is obtained as a B image.

[0084] The memory 22 stores in advance the correspondence between the scattering angle θ and the inclination of the test object S (here, the contact angle α or the contact angle β). Therefore, when it is recognized that the boundary between the flat surface S11 of the substrate S1 and the brazing filler metal S2 is obtained as part of the G image, the processing circuit 20 outputs that the scattering angle θ is between θb≦θ<θg. The processing circuit 20 reads out the contact angle α of the boundary between the flat surface S11 of the substrate S1 and the brazing filler metal S2, which corresponds to the scattering angle θ, and outputs the contact angle α to the display 6.

[0085] When the brazing filler metal S2 melts and liquefies, and the contact angle α becomes smaller, for example, to a contact angle β, as shown in Fig. 13, the liquefied brazing filler metal S2 is obtained, for example, as an R image captured through the first wavelength-selective filter 42 and a B image captured through the second wavelength-selective filter 44, as shown in Fig. 12. Note that there are cases where the brazing filler metal S2 is not obtained as an R image, but is obtained as a G image.

[0086] Therefore, when it is recognized that the boundary between the flat surface S11 of the substrate S1 and the brazing filler metal S2 is obtained as part of the B image, the processing circuit 20 outputs that the scattering angle θ is between θr≦θ<θb. The processing circuit 20 reads out the contact angle β of the boundary between the flat surface S11 of the substrate S1 and the brazing filler metal S2, which corresponds to the scattering angle θ, and outputs the contact angle β to the display 6.

[0087] When it is recognized that the boundary between the flat surface S11 of the substrate S1 and the brazing filler metal S2 is obtained as part of the R image, the processing circuit 20 outputs that the scattering angle θ is between 0≦θ<θr. The processing circuit 20 reads out the contact angle of the boundary between the flat surface S11 of the substrate S1 and the brazing filler metal S2 corresponding to that scattering angle θ, and outputs that contact angle to the display 6. In this case, the contact angle is 0<β.

[0088] In this way, the contact angle can be estimated using the optical inspection system 2 according to this embodiment. That is, in an example according to this embodiment, when the boundary between the flat surface S11 of the substrate S1 and the brazing filler metal S2 is obtained as a G image as shown in Fig. 10, the processing circuit 20 outputs to the display 6, for example, that the contact angle is angle α. When the boundary between the flat surface S11 of the substrate S1 and the brazing filler metal S2 is obtained as a B image as shown in Fig. 12, the processing circuit 20 outputs to the display 6 that the contact angle is angle β, which is smaller than angle α. Furthermore, when the boundary between the flat surface S11 of the substrate S1 and the brazing filler metal S2 is obtained as an R image, the processing circuit 20 outputs to the display 6 that the contact angle is angle β, which is smaller than angle β.

[0089] Therefore, according to this embodiment, for example, while the container 16 is operating as a heating furnace or a vacuum heating furnace, changes in the state of the test object S in the container 16 can be continuously observed in a non-contact manner through the observation window 64 of the container 16. Then, the contact angle of the brazing filler metal S2 with respect to the base material S1 of the test object S in the container 16 can be measured by photographing from above the container 16 containing the test object S. Therefore, by using the optical inspection system 2 according to this embodiment, the wettability (contact angle) of the brazing filler metal S2 with respect to the base material S1 can be evaluated by real-time monitoring without removing the test object S from the container body 62.

[0090] In this way, by using the optical inspection device 4 according to this embodiment and the optical inspection system 2 including the optical inspection device 4, it is possible to perform elemental tests on each material before applying it to a product, for example.

[0091] In this embodiment, an example has been described in which the camera 13 is disposed on the observation window 64 of the container 16 and directly above the test object S in order to melt and liquefy the brazing filler metal S2 of the test object S on the base material S1. If it is not necessary to melt a portion of the test object S and, for example, the test object S can be maintained on the stage 66, it is not necessary to dispose the camera 13 on the observation window 64 of the container 16 and directly above the test object S. For this reason, depending on the required test, the optical axis C of the camera 13 may be in any direction other than the vertical direction.

[0092] In the present embodiment, an example has been described in which white light from the light source 18 is irradiated onto the test object S through the observation window 64 via the half mirror 36. If sunlight or other light is irradiated onto the test object S with the amount of light required for the imaging unit 14 to obtain an image, the light source 18 and half mirror 36 may be unnecessary. Furthermore, if the amount of light required for the imaging unit 14 to obtain an image of the test object S is obtained by heating the test object S with the heating unit 72 in addition to sunlight or other light, the light source 18 may be unnecessary. Note that, as shown in FIG. 7 , the heating unit 72 generally emits light in the infrared and visible light ranges as the temperature of the coil 72a increases. If the temperature of the coil 72a further increases, the heating unit 72 may emit light in the ultraviolet range in addition to infrared light and visible light.

[0093] In this embodiment, the amount of light from the light source 18 is set to be greater than the amount of light from the heating unit 72. For example, when the amount of light from the heating unit 72 is relatively greater than the amount of light from the light source 18, a second color filter that cuts the wavelength of light from the heating unit 72 may be disposed, for example, between the observation window 64 and the half mirror 36 or between the half mirror 36 and the imaging optical system 32. In this case, the second color filter is used to cut wavelengths different from those of the first wavelength-selective filter 42, the second wavelength-selective filter 44, and the third wavelength-selective filter 46. The second color filter is used to cut wavelengths different from the wavelengths of R light, B light, and G light, for example, wavelengths of 600 nm and thereabouts.

[0094] The optical inspection device 4 according to this embodiment can acquire images of the substrate S1 and the brazing filler metal S2 on the flat surface S11 of the substrate S1 through the observation window 64 at room temperature before heating, during heating, and when the desired temperature of several hundred degrees Celsius or more is reached. The state of the brazing filler metal S2 as it melts can be observed at every step through the observation window 64 of the container 16. This makes it possible to continuously observe the state of the test object S inside the container 16, which becomes hot at several hundred degrees Celsius or more. This makes it possible to acquire the change in shape of the test object S corresponding to the temperature due to heating.

[0095] Furthermore, when the brazing filler metal S2 reaches its melting point, the processing circuit 20 performs image processing to measure the contact angle of the brazing filler metal S2 with respect to the flat surface S11 of the substrate S1. Therefore, the user of the optical inspection device 4 can evaluate the wettability of the brazing filler metal S2 with respect to the flat surface S11 of the substrate S1.

[0096] In this embodiment, an example has been described in which the inside of the container 16 is heated. Even if the inside of the container 16 is cooled to an environment of -196°C or lower using liquid nitrogen, for example, it is possible to acquire the change in state of the test object S in response to the temperature change using the optical inspection device 4 according to this embodiment.

[0097] According to this embodiment, an optical inspection device 4 and a method for calculating the inclination (contact angle) of a test object S in a container 16 can be provided, which can calculate the inclination (contact angle) of the test object S in a container 16 without being affected by the temperature due to heating / cooling, even if the inside of the container body 62 is heated to an appropriate temperature, such as several hundred degrees Celsius, or cooled to an appropriate temperature, such as -196 degrees Celsius or below.

[0098] Therefore, according to this embodiment, it is possible to provide an optical inspection device 4 that can inspect changes in the state of the test object S, such as the inclination (contact angle), even when the test object is sealed in the container body 62, and an optical inspection method that can calculate the inclination (contact angle) of the test object S.

[0099] The radius r1 of the first wavelength-selective filter 42, the radius r2 of the second wavelength-selective filter 42, and the radius r3 of the third wavelength-selective filter 46 of the color filter 34 according to this embodiment can be set appropriately. For example, if the contact angle θ is expected to be relatively small, the scattering angle is also expected to be small. In this case, the imaging optical system 32 is appropriately configured, and the radius r1 defining the region A1, the radius r2 defining the region A2, and the radius r3 defining the region A3 are each appropriately set, so that scattered light from the brazing material S2 of the test object S is incident on the regions A2 and A3. For example, if the contact angle θ is expected to be relatively large, the scattering angle is also expected to be large. In this case, the radius r1 defining the region A1 is appropriately increased and the regions A2 and A3 are each positioned relatively far from the optical axis C, so that scattered light from the brazing material S2 of the test object S is incident on the regions A2 and A3. Therefore, by appropriately setting the imaging optical system 32 and / or the color filter 34 in accordance with the test object S, the processing circuitry 20 can output a desired contact angle.

[0100] In addition, by changing the radii r1, r2, and r3 of the color filter 34 to match the expected contact angle, and also by adjusting the positional relationship (distance) between the test object S and the camera 13, the imaging unit 14 can acquire an image through the color filter 34 that includes angle information.

[0101] In the present embodiment, an example has been described in which an RGB camera is used as the imaging unit 14. It is also preferable to use a multispectral camera or a hyperspectral camera as the imaging unit 14. The color filter 34 can be divided into more detailed concentric regions for each wavelength to be passed, in addition to the regions A1, A2, and A3 of the three wavelength-selective filters 42, 44, and 46 described above. Therefore, by increasing the number of regions in the color filter 34 that pass different wavelengths to four or more and increasing the number of images obtained for each scattering angle θ to four or more, the processing circuit 20 can output the contact angle in more detail.

[0102] In addition, in the present embodiment, an example has been described in which the color filter 34 has a first wavelength-selective filter (wavelength-selective region) 42, a second wavelength-selective filter (wavelength-selective region) 44, and a third wavelength-selective filter (wavelength-selective region) 46. The color filter 34 may have at least two regions, for example, the first wavelength-selective filter (wavelength-selective region) 42 and the second wavelength-selective filter (wavelength-selective region) 44. In this case, the processing circuitry 20 can obtain the scattering angle θ in two angle ranges, 0≦θ<θr and θr≦θ<θb, and can also obtain the contact angle according to the scattering angle θ.

[0103] In the present embodiment, the color filter 34 is described as being formed as an area that transmits R light, B light, and G light from the inside to the outside. The color filter 34 may be formed as appropriate, for example, as an area that transmits B light, G light, and R light from the inside to the outside.

[0104] (Variation) In the optical inspection system 2 according to the first embodiment, there are various methods for detecting the three-dimensional position of the object point O of the test object S. Here, examples of methods for detecting the three-dimensional position of the object point O of the test object S will be mainly described as modified examples of the first embodiment with reference to FIGS. 14 to 18.

[0105] An optical inspection system 2 according to this modification will be described.

[0106] As shown in FIG. 14, the processing circuit (second processor) 20 of this modified example has the functions of a color extraction unit 81, an image plane position acquisition unit 83, and an object point position calculation unit 84 in addition to the scattering angle calculation unit 82 described in the first embodiment.

[0107] The image plane position acquisition unit 83 and the object point position calculation unit 84 are an example of a calculation unit. The calculation unit calculates information related to the object to be measured, including the object point O, based on the image data for each color.

[0108] The image plane position acquisition unit 83 acquires the incident position of the light ray for each of R, G, and B on the imaging plane 14a based on the output of the color extraction unit 81. The image plane position acquisition unit 83 identifies the imaging position of the light ray emitted from the object point O in each of the image data for each color.

[0109] The object point position calculation unit 84 calculates the three-dimensional position of the object point O of the test object S based on the imaging positions of the light rays on the imaging surface 14a. That is, the object point position calculation unit 84 calculates the three-dimensional position of the object point O as information related to the test object S based on a plurality of imaging positions. The three-dimensional position of the object point O of the test object S is an example of information related to the test object S. The three-dimensional position of the object point O may be expressed as the three-dimensional position of a point on the object that is the test object S.

[0110] Fig. 15 is a diagram showing an example of the configuration of the camera 13 of the optical inspection device 4 according to this modified example. Fig. 15 schematically shows an example of the light path of the chief ray of light emitted from the object point O of the test object S. As shown in Fig. 15, the optical device 12 according to this modified example includes an imaging optical system (imaging lens) 32, a first color filter 341, and a second color filter 342. The first color filter 341 and the second color filter 342 are each arranged rotationally symmetrically with respect to the optical axis C of the imaging optical system 32.

[0111] The imaging optical system 32 images a light beam emitted from an object point O on the test object S onto an image point on the imaging surface 14a of the imaging unit 14.

[0112] The first color filter 341 is disposed at a position (focal plane) of the image-side focal length f of the imaging optical system 32. Therefore, the first color filter 341 is disposed at a position corresponding to the color filter 34 according to the first embodiment.

[0113] The second color filter 342 is disposed adjacent to the imaging optical system 32. The second color filter 342 is disposed between the imaging optical system 32 and the first color filter 341. Note that the second color filter 342 may be disposed between the imaging optical system 32 and the observation window 64 of the container 16, i.e., between the imaging optical system 32 and the specimen S.

[0114] Fig. 16 is a schematic diagram showing an example of a first color filter 341 according to this modification. As shown in Fig. 16, the wavelength-selective filter provided in the opening of the first color filter 341 has two concentric wavelength-selective regions, a first region A1 and a second region A2.

[0115] The first region A1 is a region from radius ra to radius rb. A blue transmission filter that transmits blue (B) light is provided in the first region A1. In other words, the first region A1 of the first color filter 341 is a region that transmits B light.

[0116] The second region A2 is a region having a radius equal to or smaller than ra. A red transmission filter that transmits red (R) light is provided in the second region A2. In other words, the second region A2 of the first color filter 341 is a region that transmits R light. The second region A2 is disposed on the optical axis C of the imaging optical system 32.

[0117] 17 is a schematic diagram showing an example of the second color filter 342 according to this embodiment. As shown in FIG. 17, the wavelength selection member provided in the opening of the second color filter 342 has two concentric wavelength selection regions, a first region A1 and a second region A2.

[0118] The first region A1 is a region from radius ra to radius rb. A red transmission filter (fourth wavelength selection filter) that transmits red (R) light is provided in the first region A1. In other words, the first region A1 of the second color filter 342 is a region that transmits R light.

[0119] The second region A2 is a region with a radius of r1 or less. A blue transmission filter (third wavelength selection filter) that transmits blue (B) light is provided in the second region A2. In other words, the second region A2 of the second color filter 342 is a region that transmits B light. The second region A2 is disposed on the optical axis C of the imaging optical system 32. The second region A2 is formed in a disk or annular shape. Therefore, the first region A1 as a blue transmission filter is formed in an annular shape on the outer periphery of the second region A2 as a red transmission filter, and transmits B light from the test object S.

[0120] Next, the operation of the optical inspection system 2 according to this modified example will be described.

[0121] For example, by illumination by the light source 18, light rays including B light and R light are emitted from an arbitrary object point O on the test object S. These light rays pass through the observation window 64 and are reflected or scattered at the object point O. Of the light rays reflected from the arbitrary object point O on the test object S and passed through the observation window 64, the light rays that pass through the second color filter 342 and the first color filter 341 via the imaging optical system 32 are incident on the imaging surface 14a of the imaging unit 14.

[0122] Consider the light rays that are parallel to the optical axis C of the imaging optical system 32 when they are reflected from an object point O on the test object S and pass through the observation window 64 and enter the imaging optical system 32. As shown in FIG. 15 , among these light rays, the R light that passes through the first region A1 of the second color filter 342 via the imaging optical system 32 can pass through the second region A2 of the first color filter 341. On the other hand, the B light that passes through the second region A2 of the second color filter 342 via the imaging optical system 32 does not contain the wavelength component of R light and therefore cannot pass through the second region A2 of the first color filter 341. In this way, the light rays (R light and B light) that were parallel to the optical axis C of the imaging optical system 32 are incident on the first color filter 341 arranged at the image-side focus of the imaging optical system 32, but only the R light reaches the imaging surface 14a of the imaging unit 14.

[0123] Next, consider light rays that were not parallel to the optical axis of the imaging optical system 32 when they entered the imaging optical system 32. The R light that passed through the first region A1 of the second color filter 342 via the imaging optical system 32 does not contain any blue wavelength components and therefore cannot pass through the first region A1 of the first color filter 341. On the other hand, the B light that passed through the second region A2 of the second color filter 342 via the imaging optical system 32 can pass through the first region A1 of the first color filter 341. In this way, of the light rays (R light and B light) that were not parallel to the optical axis of the imaging optical system 32, only the B light reaches the imaging surface 14a of the imaging unit 14.

[0124] As described above, the optical device 12 according to this modification is a telecentric optical system that has telecentricity on the object side for the R light. On the other hand, the optical device 12 according to this modification is a non-telecentric optical system that does not have telecentricity on the object side for the B light. In the optical device 12 according to this modification, the optical axis of the telecentric optical system and the optical axis of the non-telecentric optical system coincide with each other.

[0125] The imaging unit 14 simultaneously captures, among light rays emitted from an arbitrary object point O, R light that has passed through the optical device 12 as a telecentric optical system and B light that has passed through the optical device 12 as a non-telecentric optical system. The imaging unit 14 outputs imaging data obtained by imaging to the processing circuit 20. A non-telecentric optical system may also be expressed as a normal lens optical system.

[0126] Here, the operation of the processing circuit 20 will be described.

[0127] In this modification, the processing circuit 20 can also output a contact angle based on the scattering angle θ. In this case, the processing circuit 20 operates as described in the first embodiment and can calculate the contact angle from the scattering angle θ. That is, the relationship between the scattering angle θ and the contact angle can be determined by measuring the relationship before the experiment and, for example, multiplying the scattering angle θ by an appropriate coefficient (not limited to a natural number). Therefore, a description of the operation of the processing circuit 20 to output a contact angle based on the scattering angle θ will be omitted here.

[0128] The processing circuit 20 according to this modification calculates the three-dimensional shape of the test object S based on the output of the imaging unit 14. In the measurement process, a calculation process is executed to calculate the three-dimensional position of the object point O. The calculation process includes the following color extraction process, image plane position acquisition process, and object point position calculation process. The collection of object points O then becomes the shape of the test object S.

[0129] 18 is a flowchart showing an example of the calculation process according to this embodiment. The processing circuit 20 according to this modification operates according to the flowchart shown in FIG.

[0130] In step ST21, the processing circuit 20 executes a color extraction process. The processing circuit 20, functioning as the color extraction unit 81, separates the captured image data into colors and extracts image data for each color. Note that although the term "image data" is used, it is not limited to data that can be displayed as an image, as long as the light intensity for each pixel of each color in the imaging unit 14 is extracted.

[0131] In step ST22, the processing circuit 20 executes an image plane position acquisition process. The processing circuit 20, functioning as the image plane position acquisition unit 83, identifies the imaging position of the light ray for each color based on the image data of each color. The imaging position at which the light ray is imaged can also be expressed as the incident position of the light ray on the imaging plane 14a. The processing circuit 20, functioning as the image plane position acquisition unit 83, performs image processing such as edge enhancement on the image data to identify the imaging position corresponding to the object point O. At this time, image processing such as pixel matching may be performed on the shape of the detected edge, for example.

[0132] In step ST23, the processing circuitry 20 executes an object point position calculation process. The R image, B image, and G image acquired by the imaging unit 14 according to this embodiment each have information about an angle (tilt) corresponding to the scattering angle θ of the test object S, based on the arrangement of the imaging optical system 32 and the wavelength selection filters 42, 44, and 46 of the color filter 34 (their positional relationship with the color filter 34). Therefore, for each pixel of the imaging unit 14, the processing circuitry 20 acquires information about the direction in which the object point O of the test object S exists, for each pixel and for each color.

[0133] The object point position calculation process in step ST23 will now be described in more detail.

[0134] Coordinates indicating the position of object point O of test object S in three-dimensional space are defined as (x, y, z). Coordinates indicating the incident position on imaging plane 14a of R light emitted from object point O and passed through optical device 12 as a telecentric optical system are defined as (p, q). Coordinates indicating the incident position on imaging plane 14a of B light emitted from object point O and passed through optical device 12 as a non-telecentric optical system are defined as (P, Q). The incident position on imaging plane 14a is the imaging position of the light beam.

[0135] Here, the second region A2 of the first color filter 341 is a region that transmits R light, and the second region A2 of the second color filter 342 is a region that transmits B light.

[0136] At this time, due to geometrical optics, the imaging position of the B light that has passed through the optical device 12 as a non-telecentric optical system is as follows:

[0137]

number

[0138] On the other hand, due to geometrical optics, the imaging position of the R light that has passed through the optical device 12 as a telecentric optical system is as follows:

[0139]

number

[0140] From equations (1) and (2), the position of the object point O in three-dimensional space can be calculated using the imaging positions of each ray as follows:

[0141]

number

[0142] The processing circuit 20 according to this modification can calculate the three-dimensional position of the object point O from the imaging data using equation (3). Furthermore, in the image plane position acquisition process, multiple imaging positions corresponding to multiple object points O on the test object S are acquired for each color. The collection of object points O then becomes the shape of the test object S. Therefore, the optical inspection system 2 according to this modification can detect the three-dimensional position of the object point O of the test object S inside the container body 62. Therefore, the processing circuit 20 according to this modification can calculate the three-dimensional shape of the test object S from the imaging data when the test object S is sealed inside the container body 62.

[0143] In this way, according to this modified example, in addition to an optical inspection device 4 that can inspect changes in the state of the test object S, such as the inclination (contact angle), even when the test object S is sealed in the container body 62, and an optical inspection method for calculating the inclination (contact angle) of the test object S, an optical inspection method for the shape of the test object S can be provided.

[0144] The first processor having the functions of the color extraction unit 81 and scattering angle calculation unit 82 of the processing circuit 20 described in the first embodiment, and the second processor having the functions of the color extraction unit 81, image plane position acquisition unit 83, and object point position calculation unit 84 of the processing circuit described in the modified example, may be the same or different. In other words, the first processor and the second processor may be formed as a single entity, or may be formed separately.

[0145] (Second embodiment) Next, a second embodiment will be described with reference to Figures 19 to 25. This embodiment is a modified example of the first embodiment, including modifications, and the same components as those described in the first embodiment or components having the same functions are denoted by the same reference numerals as much as possible, and detailed descriptions thereof will be omitted.

[0146] As shown in FIG. 19, in this embodiment, the optical inspection device 4 and the container body 62 and observation window 64 of the container 16 have the same structures as, for example, the first embodiment.

[0147] The heating unit 72 of the container 16 is provided on the stage 66 directly below the observation window 64. The heating unit 72 uses, for example, a halogen heater 72b. The heating unit 72 is attached to the stage 66 on which the specimen S is placed.

[0148] In this embodiment, the container 16 has a gas supply unit 80. The gas supply unit 80 includes a gas inlet valve 80a connected to the container body 62 and a gas cylinder 80b that supplies gas into the container body 62 via the gas inlet valve 80a. The gas inlet valve 80a can introduce any type of gas into the container body 62. In this embodiment, the gas sealed in the gas cylinder 80b is nitrogen gas. Therefore, the gas supply unit 80 can fill the container body 62 with nitrogen gas through the gas supply unit 80.

[0149] In this embodiment, the test object S has a Cu substrate S12, a solder material S22, and a surface-mounted component S32. The top surface S121 of the Cu substrate S12 is a horizontal plane, and the top surface S321 of the surface-mounted component S32 is a plane. The outer diameter of the Cu substrate S12 is larger than the outer diameter of the top surface S321 of the surface-mounted component S32.

[0150] The heating unit 72 is disposed between the stage 66 and the Cu substrate S12. Therefore, when the heating unit 72 is heated, heat is transferred from the Cu substrate S12 to the solder material S22, causing the solder material S22 to melt, and the surface mount components S32 and the Cu substrate S12 are joined via the solder material S22.

[0151] Here, it is desirable that the top surface S321 of the surface-mounted component S32 and the top surface S121 of the Cu substrate S12 are parallel to each other. However, if the molten solder material S22 spreads unevenly between the Cu substrate S12 and the surface-mounted component S32, a slight tilt may occur.

[0152] Using the optical inspection device 4 according to this embodiment, a test was conducted in which the inside of the container 16 was heated, the solder material S22 between the Cu substrate S12 and the surface-mounted component S32 was melted, and the inclination angle of the upper surface S321 of the surface-mounted component S32 relative to the upper surface S121 of the Cu substrate S12 was measured when the solder material S22 was liquefied.

[0153] As described above, the incident position of the scattered light component from the test object S on the imaging surface 14a and the wavelength that can pass through the color filter 34 change depending on the distance from the test object S. For this reason, the positional relationship (distance) between the test object S and the camera 13 is adjusted to adjust the relationship between the scattering angle θ and the tilt angle. Note that the relationship between the scattering angle θ and the tilt angle depending on the positional relationship (distance) between the test object S and the camera 13 can be obtained in advance by experiment.

[0154] As described above, in the example of this embodiment, for the sake of simplicity, the positional relationship between the test object S and the camera 13 is adjusted so that the scattering angle θ and the tilt angle correspond one-to-one (scattering angle θ=tilt angle). Then, the relationship between the scattering angle θ and the tilt angle is stored in the memory 22.

[0155] 19, a Cu substrate S12, a solder material S22, and a surface-mounted component S32 were placed on a stage 66 directly below an observation window 64 of a container 16. Illumination light from a light source 18 was irradiated onto the Cu substrate S12 of the test object S via a half mirror 36 and the observation window 64, and reflected light from an upper surface S121 of the Cu substrate S12 was acquired by a camera 13 via the observation window 64 and the half mirror 36. That is, an image (RGB image) of the upper surface S121 of the Cu substrate S12 was acquired by the camera 13 via the observation window 64 supported by the container body 62, and the RGB image and / or a red light image (R image), a blue light image (B image), and a green light image (G image) were displayed on the display 6.

[0156] In this embodiment, the optical axis C of the optical device 12 is adjusted so that light from the upper surface S121 of the Cu substrate S12, which is based on illumination light from the light source 18, passes through the center of the color filter 34. That is, the upper surface S121 of the Cu substrate S12 is perpendicular to the optical axis C. The specularly reflected light component (bright part) of the upper surface S121 of the Cu substrate S12 can be obtained as part of the R image. The specularly reflected components of the B image and G image from the upper surface S121 of the Cu substrate S12 are obtained as black images.

[0157] After the operator checks the display 6 to see that the upper surface S121 of the Cu substrate S12 is displayed as a bright area in the R image, the operator evacuates the inside of the container body 62. When the pressure detector 78 detects the pressure inside the container body 62, the operator determines that the degree of vacuum is, for example, 10 -3 Wait until the temperature drops below Pa.

[0158] As a result of detection by the pressure detection unit 78, the degree of vacuum in the container body 62 is 10 -3 After the pressure inside the container body 62 reaches 0.5 Pa or less, the vacuum device 76 stops operating. The operator opens the gas inlet valve 80a and introduces nitrogen gas from the gas cylinder 80b into the container body 62 via the gas inlet valve 80a. When the pressure inside the container body 62 is detected by the pressure detector 78, the operator waits until the pressure inside the container body 62 reaches about 0.5 Pa.

[0159] After the pressure inside the container body 62 reaches approximately 0.5 Pa as detected by the pressure detection unit 78, the operator supplies power to the halogen heater 72b of the heating unit 72 to heat the stage 66, and starts measuring the angle information of the inclination (tilt angle) of the upper surface S121 of the Cu substrate S12 using the optical inspection device 4 based on the image captured by the camera 13.

[0160] For example, the temperature inside the container body 62 is measured by a temperature detection unit (thermocouple) 74. The worker confirms that the solder material S22 between the Cu substrate S12 and the surface-mounted component S32 has reached the melting point (here, 230° C.).

[0161] When the solder material S22 melts, the inclination angle of the upper surface S321 of the surface mount component S32 relative to the upper surface S121 of the Cu substrate S12 may change. The inclination angle of the upper surface S321 of the surface mount component S32 relative to the upper surface S121 of the Cu substrate S12 at the point when the solder material S22 further melts and the inclination of the upper surface S321 of the surface mount component S32 relative to the upper surface S121 of the Cu substrate S12 settles down is defined as the final inclination angle of the upper surface S321 of the surface mount component S32 relative to the upper surface S121 of the Cu substrate S12.

[0162] For example, as a result of the solder material S22 melting, the upper surface S321 of the surface-mounted component S32 may become parallel or approximately parallel to the upper surface S121 of the Cu substrate S12, as shown in Fig. 20. At this time, the imaging unit 14 acquires an image of the upper surface S321 of the surface-mounted component S32 as a specular reflection component, along with the upper surface S121 of the Cu substrate S12. Therefore, on the display 6 of the optical inspection system 2, as shown in Fig. 21, an image of the upper surface S321 of the surface-mounted component S32 is displayed in the R image, along with the upper surface S121 of the Cu substrate S12.

[0163] The relationship between the channel through which an image is obtained and the scattering angle is recorded in advance in the memory 22. Therefore, when it is recognized that the upper surface S321 of the surface-mounted component S32 will be obtained as an R image, the processing circuit 20 reads out the tilt angle corresponding to the scattering angle in that image from the memory 22. The processing circuit 20 then outputs that tilt angle to the display 6. In the example shown in Fig. 20, an R image is obtained, so the processing circuit 20 outputs to the display 6 that the tilt angle (= scattering angle) is 0°.

[0164] For example, as a result of the solder material S22 melting, the upper surface S321 of the surface-mounted component S32 may be tilted at an angle (tilt angle) α with respect to the upper surface S121 of the Cu substrate S12, as shown in Fig. 22. In this case, the imaging unit 14 acquires an image of the upper surface S121 of the Cu substrate S12 as a specular reflection component. Note that, depending on the tilt angle of the upper surface S321 of the surface-mounted component S32, the imaging unit 14 may not be able to acquire any of the R image, B image, and G image. In the case of the tilt angle α, the imaging unit 14 acquires the image of the upper surface S321 of the surface-mounted component S32 as a G image, as shown in Fig. 23.

[0165] The relationship between the channel through which an image is obtained and the scattering angle is recorded in advance in the memory 22. Therefore, when it is recognized that the upper surface S321 of the surface-mounted component S32 is obtained as a G image, the processing circuit 20 reads out the tilt angle corresponding to the scattering angle in that image from the memory 22. The processing circuit 20 then outputs that tilt angle to the display 6. In the example shown in FIG. 22, since a G image is obtained, the processing circuit 20 outputs to the display 6 that the tilt angle (= scattering angle) is angle α.

[0166] For example, as a result of the solder material S22 melting, the upper surface S321 of the surface-mounted component S32 may be tilted at an angle (tilt angle) β (<α) with respect to the upper surface S121 of the Cu substrate S12, as shown in Fig. 24. In this case, the imaging unit 14 acquires an image of the upper surface S121 of the Cu substrate S12 as a specular reflection component. In the case of the tilt angle β, the imaging unit 14 acquires an image of the upper surface S321 of the surface-mounted component S32 as image B, as shown in Fig. 25.

[0167] The relationship between the channel through which an image is obtained and the scattering angle is recorded in advance in the memory 22. Therefore, when it is recognized that the upper surface S321 of the surface-mounted component S32 will be obtained as the B image, the processing circuit 20 reads out the tilt angle corresponding to the scattering angle in that image from the memory 22. The processing circuit 20 then outputs that tilt angle to the display 6. In the example shown in FIG. 24, since the B image is obtained, the processing circuit 20 outputs to the display 6 that the tilt angle (= scattering angle) is angle β.

[0168] The tilt angles α and β are usually in the range of, for example, 0° to several degrees.

[0169] After the solder material S22 is melted, it is desirable that the upper surface S321 of the surface-mounted component S32 be parallel to the upper surface S121 of the Cu substrate S12. However, if the molten solder material S22 spreads unevenly, a slight tilt may occur in the upper surface S321 of the surface-mounted component S32 relative to the upper surface S121 of the Cu substrate S12. According to this embodiment, by observing the change in the angle between the upper surface S321 of the surface-mounted component S32 and the upper surface S121 of the Cu substrate S12 before the solder material S22 melts and after the solder material S22 has melted and the Cu substrate S12 and the surface-mounted component S32 are joined, it is possible to discover poor joining between the surface-mounted component S32 and the Cu substrate S12.

[0170] According to this embodiment, an optical inspection device 4 and a method for calculating the inclination of a test object S can be provided that can calculate the inclination of a test object S without being affected by the temperature caused by heating, even when the inside of the container body 62 is heated to several hundred degrees Celsius or more.

[0171] According to this embodiment, it is possible to provide an optical inspection device 4 that can calculate the tilt of a test object S even in an appropriate gas atmosphere without being affected by the gas, and a method for calculating the tilt of a test object S.

[0172] Also in this embodiment, the shape of the test object can be detected using the method for detecting the shape of the test object by the method described in the first embodiment or the method described in the modified example of the first embodiment. Therefore, according to this embodiment, it is possible to provide an optical inspection device 4 and a method for detecting the shape of the test object S that can detect the shape of the test object S without being affected by the temperature of the heating unit 72 even when the inside of the container body 62 is heated to several hundred degrees Celsius.

[0173] Therefore, according to this embodiment, it is possible to provide an optical inspection device 4 that can inspect changes in the state of the test object S, such as its inclination, even when the test object is sealed within the container body 62, an optical inspection method for the test object S, and an optical inspection method for the shape of the test object S.

[0174] According to at least one of the embodiments described above, it is possible to provide an optical inspection device that can inspect changes in the state of a test object, such as the inclination of the test object, even when the test object is sealed within the container body, an optical inspection method for a test object, and an optical inspection method for the shape of the test object.

[0175] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0176] 2...optical inspection system, 4...optical inspection device, 12...optical device, 13...camera, 14...imaging section, 14a...imaging surface, 16...container, 18...light source, 32...imaging optical system, 34...color filter, 36...half mirror, 42, 44, 46...wavelength selection filter, 48...light shielding section, 62...container body, 62a...opening edge, 64...observation window, 64a, 64b...parallel surfaces, 66...stage, 72...heating section, 74...temperature detection section, 76...vacuum device, 78...pressure detection section

Claims

1. a container having a container body in which a test object is accommodated, and an observation window which separates the inside and outside of the container body and has a pair of parallel surfaces through which light from the test object passes; an imaging optical system that forms an image of light rays from the test object that have passed through the observation window; a lens element disposed rotationally symmetrically with respect to an optical axis of the imaging optical system and provided on a focal plane of the imaging optical system; a first wavelength-selective filter having a disk shape or an annular shape, which is provided on the optical axis of the imaging optical system and passes through the imaging optical system and transmits light having a first wavelength from the test object; and a second wavelength-selective filter formed in an annular shape on the outer periphery of the first wavelength-selective filter, the second wavelength-selective filter passing through the imaging optical system and the light beam from the test object having a second wavelength different from the first wavelength; a color filter having an imaging unit that is provided on an imaging plane of the imaging optical system and captures an image of the light ray of the first wavelength that has passed through the first wavelength selection filter and the light ray of the second wavelength that has passed through the second wavelength selection filter; An optical inspection device comprising:

2. the container has a heating unit that heats the test object, The container body and the observation window have heat resistance that suppresses deformation due to heat from the heating unit. The optical inspection device according to claim 1 .

3. 3. The optical inspection device according to claim 2, wherein the first wavelength-selective filter and the second wavelength-selective filter of the color filter are formed to block a peak wavelength of light emitted from the heating portion when the heating portion is heated.

4. 4. The optical inspection device according to claim 1, further comprising a first processor that outputs the contact angle of the liquid with respect to the substrate at the boundary between the substrate as the test object and the liquid as the test object on the substrate based on an image captured by the imaging unit.

5. a scattering angle of the light beam of the second wavelength relative to the light beam of the first wavelength is set by a size of a radial area of ​​the first wavelength-selective filter and the second wavelength-selective filter, The scattering angle corresponds to the contact angle. The optical inspection device according to claim 4 .

6. a second processor that generates a first image by a light ray of the first wavelength that passes through the first wavelength selection filter and a second image by a light ray of the second wavelength that passes through the second wavelength selection filter based on image data captured by the imaging unit, 6. An optical inspection device according to claim 1, wherein the second processor identifies an imaging position of a point on the test object in each of the first image and the second image, and calculates a three-dimensional position of the point on the test object as information related to the test object based on a plurality of the imaging positions.

7. a lens element is disposed rotationally symmetrically with respect to the optical axis between the imaging optical system and the color filter, or between the imaging optical system and the observation window; a third wavelength-selective filter having a disk shape or an annular shape, which is provided on an optical axis of the imaging optical system and which passes the light beam of the second wavelength from the test object; and a fourth wavelength-selective filter formed in an annular shape around the outer periphery of the third wavelength-selective filter, the fourth wavelength-selective filter passing the light beam of the first wavelength from the object to be measured; a second color filter having The optical inspection device of claim 6 , comprising:

8. 8. The optical inspection device according to claim 1, wherein a vacuum device is connected to the container body.

9. 9. The optical inspection device according to claim 1, wherein a gas introduction valve capable of introducing any type of gas is connected to the container body.

10. 6. An optical inspection method for inspecting a boundary between the substrate and the liquid of the test object using the optical inspection device according to claim 4 or 5, comprising: an image of the light beam of the first wavelength that has passed through the first wavelength selection filter and the light beam of the second wavelength that has passed through the second wavelength selection filter is captured by the image capturing unit; and outputting the contact angle at the boundary between the substrate and the liquid based on the image captured by the imaging unit. A method for optically inspecting the object to be inspected.

11. 8. An optical inspection method for inspecting a shape of the test object using the optical inspection device according to claim 6 or 7, comprising: generating the first image by the light beam of the first wavelength that has passed through the first wavelength selection filter and the second image by the light beam of the second wavelength that has passed through the second wavelength selection filter based on the image data captured by the imaging unit; Identifying the imaging positions of the points on the test object in each of the first image and the second image; calculating a three-dimensional position of a point on the test object as information related to the test object based on the plurality of imaging positions; A method for optically inspecting the shape of the test object.

Images