Three-dimensional shape inspection device and three-dimensional shape inspection method

Abstract

A three-dimensional shape inspection apparatus according to a representative embodiment includes: a light irradiation unit including a light source and a spatial light modulator configured to modulate light received from the light source so as to irradiate a plurality of lights having a plurality of focal points downward onto a surface of a measurement object; an optical system that refracts each of the modulated lights at different refractive indexes at a plurality of wavelengths according to chromatic aberration, thereby forming a measurement interval in which the lights refracted at the wavelengths are focused in the vertical direction; an optical splitter that transmits a portion of the light reflected by the object to be measured and reflects another portion of the light reflected by the object to be measured; a first detection unit that detects wavelength information of light transmitted from the optical splitter; and a second detection unit that detects wavelength information of the light reflected from the optical splitter. The filter detection unit, which is either the first detection unit or the second detection unit, includes a filter unit that blocks light of a specific wavelength or more, and detects information of light that does not reach the specific wavelength.

Description

Technical Field

[0001] The present invention relates to a three-dimensional shape inspection device and a three-dimensional shape inspection method. Background Art

[0002] Confocal microscopy or confocal laser scanning microscopy (CLSM) is a microscope that removes out-of-focus light through a pinhole. It can eliminate light interference generated in areas outside the focus to achieve high resolution and high magnification. It is used in life sciences, semiconductors, materials science and other fields.

[0003] Among confocal microscopes, a chromatic confocal microscope is known that uses chromatic aberration to perform three-dimensional inspection of the measurement object. The chromatic confocal microscope refracts white light emitted by a light source at different refractive indices according to multiple wavelengths, and irradiates the refracted light onto the surface of the measurement object. The inspection is performed in the following manner: the light refracted by wavelength that is focused and reflected on the surface of the measurement object passes through a pinhole, and the wavelength of the light that passes through is detected by a spectrometer. The chromatic confocal microscope tabulates the wavelength information of the focused light and the focal length information of the corresponding optical system in advance, and performs three-dimensional inspection by measuring the height of the measurement object based on the wavelength information of the detected light. Summary of the invention

[0004] Technical issues

[0005] The existing color confocal microscope performs three-dimensional inspection by detecting the light reflected by the light emitted from the light source irradiating only one point on the surface of the measurement object, so it can only implement point scanning or line scanning of a small length, which has the limitation of very slow inspection speed. The embodiments of the present disclosure solve the problems existing in the above-mentioned prior art.

[0006] In addition, when the measurement object includes a transparent body, the existing color confocal microscope has the problem that the measurement object can only be inspected if the refractive index information of the transparent body is known in advance. In addition, depending on the shape of the sample of the measurement object including the transparent body, there is a situation where the inspection cannot be performed, and thus there is a problem that whether the inspection can be performed depends on the shape of the sample. The embodiments of the present disclosure solve the above problems of the prior art.

[0007] Technical Solution

[0008] One aspect of the present disclosure provides an embodiment of a three-dimensional shape inspection device. A three-dimensional shape inspection device of a representative embodiment includes: a light irradiation unit, the light irradiation unit includes a light source and a spatial light modulator configured to modulate light received from the light source, thereby irradiating multiple lights with multiple focal points downward onto the surface of a measurement object; an optical system, the optical system refracts the modulated lights at multiple wavelengths with mutually different refractive indices according to chromatic aberration, thereby forming a measurement interval in the upper and lower directions of the light refracted by wavelength focus; an optical splitter, the optical splitter transmits a portion of the light reflected by the measurement object and reflects another portion of the light reflected by the measurement object; a first detection unit, the first detection unit detects wavelength information of light transmitted from the optical splitter; and a second detection unit, the second detection unit detects wavelength information of light reflected from the optical splitter; wherein the filter detection unit as either the first detection unit or the second detection unit includes a filter unit that blocks light above a specific wavelength and detects information of light that does not reach the specific wavelength.

[0009] In one embodiment, the three-dimensional shape inspection device may further include: a control unit that measures the height of the base of the measurement object and the height of the transparent body arranged on the base based on the information detected by the first detection unit and the information detected by the second detection unit.

[0010] In one embodiment, the light filtering detection section may be configured to detect light intensity information.

[0011] In one embodiment, the three-dimensional shape inspection device may also include: a focus adjustment unit, which enables the measurement interval to be changed by changing the focus position of the light refracted according to the wavelength in the up and down directions; and a control unit, which is configured to control the focus adjustment unit to change the measurement interval when it is determined that the intensity information of the light is below a predetermined first specific intensity.

[0012] In one embodiment, when the control unit determines that the intensity information of the light is less than a predetermined first specific intensity, the control unit may control the focus adjustment unit to change the measurement interval so that light with a shorter wavelength is reflected toward the measurement object.

[0013] In one embodiment, the three-dimensional shape inspection device may also include: a focus adjustment unit, which enables the measurement interval to be changed by changing the focus position of the light refracted according to the wavelength in the up and down directions; and a control unit, which is configured to control the focus adjustment unit to change the measurement interval when it is determined that the intensity information of the light is above a predetermined second specific intensity.

[0014] In one embodiment, when it is determined that the light intensity information is equal to or greater than a predetermined second specific intensity, the control unit may control the focus adjustment unit to change the measurement interval so that light with a longer wavelength is reflected toward the measurement object.

[0015] In one embodiment, the three-dimensional shape inspection device may also include: a focus adjustment unit, which enables the measurement interval to be changed by changing the focus position of the light refracted according to the wavelength in the up and down directions; and a control unit, which controls the focus adjustment unit to change the measurement interval when the intensity information of the light meets a predetermined benchmark; wherein the first detection unit and the second detection unit can detect the wavelength information of the light again in the state where the measurement interval is changed.

[0016] In one embodiment, the control unit may be configured to: (i) obtain first information detected by a non-filtering detection unit that is not the filtering detection unit in the first detection unit and the second detection unit, and obtain second information detected by the filtering detection unit in a first state before changing the measurement interval; (ii) obtain third information detected by the non-filtering detection unit and fourth information detected by the filtering detection unit in a second state after changing the measurement interval; and (iii) measure the height of the base of the measured object and the height of a transparent body arranged on the base based on the first information, the second information, the third information and the fourth information.

[0017] In one embodiment, when a value proportional to the average value of the distance from the optical system to the focusing position of the light refracted by the wavelength is defined as the working distance, the control unit may measure the refractive index of the transparent body based on the working distance in the first state, the working distance in the second state, the first information and the third information.

[0018] In one embodiment, the optical system has an inherent focus offset value for each wavelength according to chromatic aberration. When a value proportional to an average value of the distance from the optical system to the focusing position of the light refracted according to the wavelength is defined as the working distance, the control unit can measure a refractive index, which is a value obtained by subtracting the working distance in the second state from the working distance in the first state, divided by a value obtained by subtracting the first focus offset value corresponding to the first information from the third focus offset value corresponding to the third information.

[0019] In one embodiment, the control section may measure the height of the base of the measurement object and the height of a transparent body disposed on the base based on the first information, the second information, the third information, the fourth information, and the refractive index.

[0020] In one embodiment, the focus adjustment unit may include: a variable lens, which can change the measurement interval based on the applied current; and the greater the applied current, the greater the value obtained by subtracting the working distance in the second state from the working distance in the first state.

[0021] In one embodiment, the light filtering detection unit may be the second detection unit.

[0022] In one embodiment, the spatial light modulator may include: a plurality of digital micromirror devices that modulate light received from the light source by reflecting light and are arranged in an array.

[0023] In one embodiment, the first detection section and the second detection section may detect color information of light focused and reflected at a position corresponding to a height of a base of the measurement object or a height of a transparent body disposed on the base, among the light refracted by wavelength.

[0024] In one embodiment, the light irradiation section may irradiate the plurality of lights having a plurality of focal points in a horizontal direction perpendicular to an up-down direction downward onto the surface of the measuring object.

[0025] Another aspect of the present disclosure provides an embodiment of a three-dimensional shape inspection method. The three-dimensional shape inspection method of a representative embodiment includes: a light modulation step, modulating the light received from the light source so that multiple lights with multiple focal points are irradiated onto the surface of the measured object; a light irradiation step, irradiating light to the lower side so that the modulated lights are refracted at different refractive indices according to the chromatic aberration at multiple wavelengths, thereby forming a measurement interval in the upper and lower directions of the light focus refracted according to the wavelength; a light path forming step: by means of an optical splitter, a part of the light reflected by the measured object is transmitted, and another part of the light reflected by the measured object is reflected; a first detection step, detecting the wavelength information of the light transmitted in the light path forming step; and a second detection step, detecting the wavelength information of the light reflected in the light path forming step; wherein either of the first detection step and the second detection step includes: a filtering detection step, blocking light above a specific wavelength and detecting information of light that does not reach the specific wavelength.

[0026] In one embodiment, the filtering detection step can detect the intensity information of light, and the three-dimensional shape inspection method may also include: a focus adjustment step, when it is determined that the intensity information of the light is below a predetermined first specific intensity or above a predetermined second specific intensity, the measurement interval is changed by changing the focus position of the light refracted by the wavelength in the up and down directions.

[0027] In one embodiment, the filtering detection step can detect the intensity information of light, and the three-dimensional shape inspection method may also include: a focus adjustment step, when the intensity information of the light meets a predetermined benchmark, the measurement interval is changed by changing the focus position of the light refracted by the wavelength in the up and down directions, and the first detection step and the second detection step are performed again in a state where the measurement interval is changed.

[0028] Effects of the Invention

[0029] According to an embodiment of the present disclosure, a large area of ​​a measurement object can be three-dimensionally inspected at a faster speed by using a spatial light modulator and an image sensor that detects color information of light.

[0030] According to the embodiments of the present disclosure, there is an effect that, even in a case where a transparent body is included in the measurement object, inspection of the measurement object can be achieved without requiring refractive index information of the transparent body.

[0031] According to an embodiment of the present disclosure, there is an effect that, even in a case where the measurement object includes a transparent body, inspection of the measurement object can be achieved regardless of the shape of the measurement object. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 1 is a schematic diagram showing a driving method of the three-dimensional shape inspection device according to the comparative embodiment of the present disclosure.

[0033] Figure 2 It describes that when a transparent body is arranged on the base of the measurement object, Figure 1 Schematic diagram of problems existing in the three-dimensional shape inspection device of the comparative embodiment.

[0034] Figure 3 is Figure 2 In this case, a graph showing the wavelength and intensity of light detected by the spectrometer of the three-dimensional shape inspection device of the comparative example is shown.

[0035] Figure 4 It is a schematic diagram for describing problems occurring in an inspection situation of the three-dimensional shape inspection device of the comparative embodiment according to the shapes of the base and the transparent body.

[0036] Figure 5 It is an overall stereoscopic diagram of a three-dimensional shape inspection device according to an embodiment of the present disclosure.

[0037] Figure 6 is along Figure 5 A cross-sectional view taken along line A1-A1` is shown.

[0038] Figure 7 Schematic diagram showing a digital micromirror device used in an embodiment of the present disclosure.

[0039] Figure 8 is a schematic diagram showing a charge coupled device (CCD) used in an embodiment of the present disclosure.

[0040] Fig. 9 3 is a schematic diagram showing a process of obtaining RGB information of light by a 3-charge coupled device according to an embodiment of the present disclosure.

[0041] Fig.10 It shows that Fig. 9 Conceptual diagram of the process of converting the RGB information obtained in the image into the HSV coordinate system.

[0042] Fig.11 Schematic diagram showing the operating state of the three-dimensional shape inspection device according to an embodiment of the present disclosure.

[0043] Fig.12 Is a description Fig.11 A diagram showing the operation mode of the filter unit for blocking light of a specific wavelength or above.

[0044] Fig.13 1 is a schematic diagram showing light focused and reflected at a position corresponding to the height of the base of the measurement object or the height of a transparent body arranged on the base, among the light refracted by the optical system according to the wavelength.

[0045] Fig.14 This is a graph showing a case where the intensity information of light detected by the light filter detection unit is determined to be equal to or less than a predetermined first specific intensity.

[0046] Fig.15 This is a graph showing a case where the intensity information of light detected by the light filter detection unit is determined to be equal to or higher than a predetermined second specific intensity.

[0047] Fig.16 This is a graph showing a case where the intensity information of light detected by the light filter detection unit satisfies a predetermined standard.

[0048] Fig.17 1 is a schematic diagram showing that the three-dimensional shape inspection device according to an embodiment of the present disclosure can perform inspection regardless of the shapes of the base and the transparent body.

[0049] Fig.18 1 is a schematic diagram for describing a manner in which a three-dimensional shape inspection apparatus according to an embodiment of the present disclosure measures a height of a base of a measurement object and a height of a transparent body arranged on the base.

[0050] Fig.19 : is a graph showing the inherent focus shift values ​​of each wavelength of the optical system according to an embodiment of the present disclosure.

[0051] Fig. 20 This is a flowchart showing the flow of one embodiment of the three-dimensional shape inspection method of the present disclosure.

[0052] Fig.21 This is a flowchart showing the flow of one embodiment of the three-dimensional shape inspection method of the present disclosure when the measurement object includes a transparent object. DETAILED DESCRIPTION

[0053] Best Mode for Carrying Out the Invention

[0054] The embodiments of the present disclosure are listed for the purpose of describing the technical concept of the present disclosure. The scope of rights of the present disclosure is not limited to the embodiments disclosed below or the specific description of these embodiments.

[0055] Unless otherwise defined, all technical terms and scientific terms used in the present invention have the meanings commonly understood by those with common sense in the technical field to which the present invention belongs. All terms used in the present disclosure are selected for the purpose of more clearly describing the present disclosure, and are not selected for limiting the scope of rights according to the present disclosure.

[0056] Expressions such as “including,” “having,” and “having” used in the present invention should be understood as open-ended terms that may include other embodiments unless otherwise mentioned in the sentence or text containing the corresponding expression.

[0057] Singular expressions described in the present invention may include plural meanings unless otherwise mentioned, and the same applies to singular expressions recorded in the scope of patent applications.

[0058] The expressions “first”, “second”, etc. used in the present disclosure are used to distinguish a plurality of components from each other, and do not limit the order or importance of these components.

[0059] The term "unit" used in the present disclosure means software, or hardware components such as field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs). However, "units" are not limited to hardware and software. "Units" may exist in addressable storage media, or may drive one or more processors. Therefore, for example, "units" include components such as software components, object-oriented software components, class components, and task components, as well as processors, functions, attributes, processes, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided in the components and "units" may be combined into fewer components and "units", or may be further separated into additional components and "units".

[0060] The expression "based on..." used in the present disclosure is used to describe one or more factors described in the phrase or sentence containing the expression and affecting the behavior or action of decision or judgment, and the expression does not exclude other factors affecting the behavior or action of decision or judgment.

[0061] In the present disclosure, when it is mentioned that a certain constituent element is “connected to” or “accessed to” another constituent element, it should be understood that the certain constituent element can be directly connected to or accessed to the other constituent element, or can be connected or accessed through other new constituent elements.

[0062] Directional indicators such as "below" and "lower" used in the present disclosure are based on the direction of the measured object relative to the three-dimensional shape inspection device in the attached drawings, and directional indicators such as "above" and "upper" indicate the opposite direction, but this is only a description to enable the present disclosure to be clearly understood, and different definitions may be given to each direction depending on the reference placement position.

[0063] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. In the drawings, identical or corresponding constituent elements are given identical reference numerals. In addition, in the description of the following embodiments, repeated descriptions of identical or corresponding constituent elements may be omitted. However, even if the description of the relevant constituent elements is omitted, it does not mean that such constituent elements are not included in a certain embodiment.

[0064] Figure 1 1 is a schematic diagram showing a driving method of the three-dimensional shape inspection device according to the comparative embodiment of the present disclosure.

[0065] Reference Figure 1 The operation of the three-dimensional shape inspection device 50 of the comparative embodiment is described as follows.

[0066] The three-dimensional shape inspection device 50 can irradiate light onto the surface of the measurement object 20 by allowing the light emitted by the light source 52 to pass through the beam splitter 54. The light source 52 can emit light having multiple wavelengths. The measurement object 20 may include a variety of inspection objects such as cells, metal and non-metal materials, and semiconductor substrates used in the fields of life sciences, semiconductors, and materials sciences. In addition, the measurement object 20 may include materials such as transparent bodies, and may include mirror surfaces (C4 bumps, μ bumps, patches, etc.) of semiconductors, etc.

[0067] The light passing through the beam splitter 54 may be refracted by the optical system 56. The optical system 56 may refract the incident light according to the multiple wavelengths with different refractive indices according to the chromatic aberration. The optical system 56 may focus the light with a longer wavelength to a position farther from the optical system 56 and focus the light with a shorter wavelength to a position closer to the optical system 56 according to the chromatic aberration. For example, referring to Figure 1, shows a state in which light having a plurality of wavelengths is refracted by the optical system 56 at different refractive indices, light having the shortest wavelength (λ1) among the plurality of wavelengths is focused at a position closest to the optical system 56, and light having the longest wavelength (λn) among the plurality of wavelengths is focused at a position farthest from the optical system 56. Among the light refracted at the plurality of wavelengths, there may be light having a height corresponding wavelength (λm) focused at a position corresponding to a height on the surface of the measuring object 20. The height corresponding wavelength (λm) may have a value between the shortest wavelength (λ1) and the longest wavelength (λn).

[0068] The plurality of wavelength-refracted lights are reflected from the surface of the measuring object 20 and reflected by the beam splitter 54. The beam splitter 54 may reflect the respective lights having the plurality of wavelengths reflected from the surface of the measuring object 20 toward the pinhole 58. The beam splitter 54, the optical system 56, and the pinhole 58 may focus and allow only the light having the height-corresponding wavelength (λm) among the respective lights having the plurality of wavelengths to pass through the pinhole 58, the light having the height-corresponding wavelength (λm) being focused and reflected at a position corresponding to the height on the surface of the measuring object 20. A spectrometer 60 may be formed on the optical path passing through the pinhole 58. The spectrometer 60 may detect the light by a spectrum according to the wavelength to detect the intensity information of the light based on the wavelength.

[0069] The three-dimensional shape inspection device 50 can detect the wavelength component of the light focused on the surface of the measuring object 20 through the spectrometer 60, thereby measuring the height of the measuring object 20. The three-dimensional inspection of the three-dimensional shape of the measuring object 20 can be performed by horizontally moving the three-dimensional shape inspection device 50 or the measuring object 20. The three-dimensional shape inspection device 50 of the comparative embodiment can only implement a point scanning method or a line scanning method of a small length, so there is a limitation that the inspection speed is very slow, wherein the point scanning method is to perform a three-dimensional inspection by irradiating only one point on the surface of the measuring object with the light emitted from the light source 52. The inspection speed of the point scanning method of the three-dimensional shape inspection device 50 of the comparative embodiment may be less than 1mm2.

[0070] Figure 2 It describes that when a transparent body is arranged on the base of the measurement object, Figure 1 Schematic diagram of problems existing in the three-dimensional shape inspection device of the comparative embodiment. Figure 3 is Figure 2 In this case, a graph showing the wavelength and intensity of light detected by the spectrometer of the three-dimensional shape inspection device of the comparative example is shown.

[0071] Reference Figure 2, the measuring object 20 may include a base 22 and a transparent body 24. The transparent body 24 may be arranged on the base 22. The transparent body 24 is a medium in which light travels and is transmitted. The refractive index (n) of the transparent body 24 may be different from the refractive index of the space in which the light travels before passing through the transparent body 24 arranged in the space. The refractive index (n) of the transparent body 24 is different from the refractive index of other spaces, so that the light incident on the transparent body 24 is refracted and passes through the transparent body 24.

[0072] like Figure 3 As shown, the three-dimensional shape inspection device 50 is a device for measuring the height of the measuring object 20 by detecting the wavelength component of the light focused on the surface of the measuring object 20. When the transparent body 24 is arranged on the base 22 of the measuring object 20, there may be two components of the wavelength component of the light focused and reflected on the surface of the measuring object 20. For example, there may be a wavelength (λ1) component of the light focused and reflected on the surface of the transparent body 24 of the measuring object 20 and a wavelength (λ2) component of the light focused and reflected on the surface of the base 22 of the measuring object 20. If the wavelength (λ1) component of the light focused and reflected on the surface of the transparent body 24 of the measuring object 20 is detected, the distance (h0) from the optical system to the transparent body surface can be measured. However, if the wavelength (λ2) component of the light focused and reflected on the surface of the base 22 of the measuring object 20 is detected, the h0+h1 distance, which is the distance corresponding to the wavelength (λ2) of the light, can be measured. The distance (h0+h1) measured based on the wavelength (λ2) of the light reflected and detected on the surface of the base 22 is different from the distance (h0+h1+h2) from the optical system to the actual base, so the detection accuracy of the three-dimensional shape inspection device may be reduced. Therefore, without information on the refractive index (n) of the transparent body, it is impossible to perform the work of correcting the measured distance (h0+h1) to the distance (h0+h1+h2) from the optical system to the actual base.

[0073] Figure 4 It is a schematic diagram for describing a problem occurring in the three-dimensional shape inspection device of the comparative embodiment according to the shapes of the base and the transparent body.

[0074] Reference Figure 1 and Figure 4 , showing a state in which light having a plurality of wavelengths is refracted with different refractive indices by the optical system 56, light having the shortest wavelength (λ1) among the plurality of wavelengths is focused at a position closest to the optical system 56, and light having the longest wavelength (λn) among the plurality of wavelengths is focused at a position farthest from the optical system 56. In addition, the plurality of wavelengths may include any wavelength (λp, λq) having a value between the shortest wavelength (λ1) and the longest wavelength (λn).

[0075] like Figure 4As shown in (a), among the light refracted by the optical system according to wavelength, there is light focused at a position corresponding to the height of the base 22 or the height of the transparent body 24, and the wavelength of the focused light has a wavelength (λp, λq) value between the shortest wavelength (λ1) and the longest wavelength (λn). Figure 4 In the case shown in (a), the inspection can be performed based on the height corresponding to the detected wavelength (λp, λq). Figure 4 In the cases shown in (b) and (c), inspection may not be possible depending on the shape of the sample.

[0076] like Figure 4 As shown in (b), the measurement object 20 may be a sample in which the base 22 is very thick. Since the base 22 is very thick, among the light refracted by the optical system according to the wavelength, there may be only light focused at a position corresponding to the height of the base 22, and there may be no light focused at a position corresponding to the height of the transparent body 24. Figure 4 In the case shown in (b), since the transparent body 24 cannot be inspected, the measurement object 20 may not be inspected.

[0077] like Figure 4 As shown in (c), the measurement object 20 may be a sample in which the transparent body 24 is very thick. Since the transparent body 24 is very thick, among the light refracted by the optical system according to the wavelength, there may be only light focused at a position corresponding to the height of the transparent body 24, and there may be no light focused at a position corresponding to the height of the base 22. Figure 4 In the case shown in (c), since the base 22 cannot be inspected, the measurement object 20 may not be inspected.

[0078] In contrast, the following reference Figures 5 to 21 The three-dimensional shape inspection device and the three-dimensional shape inspection method of one embodiment of the present disclosure described have the effect of being able to perform high-speed large-area three-dimensional inspection of the measurement object using a spatial light modulator and an image sensor for detecting color information of light. In addition, a three-dimensional shape inspection device and a three-dimensional shape inspection method are provided, which can inspect the inspection object including a transparent body even if the refractive index of the transparent body is unknown, and can inspect regardless of the sample shape of the inspection object.

[0079] Figure 5 It is an overall stereoscopic diagram of a three-dimensional shape inspection device according to an embodiment of the present disclosure. Figure 6 is along Figure 5 A cross-sectional view taken along line A1-A1` is shown.

[0080] Reference Figure 5 and Figure 6 , the three-dimensional shape inspection device 10 can inspect the three-dimensional shape of the measuring object 20. The three-dimensional shape inspection device 10 can irradiate light to the measuring object 20 and detect information of the reflected light to inspect the shape of the measuring object 20. The three-dimensional shape of the measuring object 20 can be inspected by moving the three-dimensional shape inspection device 10 or the measuring object 20 and detecting the position and height on multiple surfaces of the measuring object 20. Figure 5 In the figure, for the convenience of description, the three-dimensional shape inspection device 10 and the measurement object 20 are shown to be located at the same point, but the present disclosure is not limited thereto, and the three-dimensional shape inspection device 10 and the measurement object 20 can be moved in the up and down direction or the horizontal direction for inspection.

[0081] The three-dimensional shape inspection device 10 may include a light irradiation unit 100 , an optical system, a light splitter 230 , and an image sensor 400 .

[0082] The light irradiation unit 100 may irradiate light onto the surface of the measurement object 20. The light irradiation unit 100 may irradiate light toward a lower side direction where the measurement object 20 is located.

[0083] The light irradiation unit 100 may include a light source (not shown) and a spatial light modulator 110. The light source may be a white light source having multiple wavelengths. The light source may include any one of an LED, a halogen lamp, or a xenon lamp. The light source may include a sun-like LED. The present disclosure is not limited thereto, and any light source capable of emitting light having multiple wavelengths may be used in the present disclosure.

[0084] The light irradiation unit 100 may include a light irradiation unit housing 150 that introduces the light L of the light source into the interior of the three-dimensional shape inspection device 10. A space is formed inside the light irradiation unit housing 150 to receive the light L of the light source. The internal space of the light irradiation unit housing 150 may be a path through which the light L of the light source irradiates the measurement object 20. The light irradiation unit housing 150 may include a light receiving unit 152 formed with a hole and protruding outward. The light L of the light source may be received into the interior of the three-dimensional shape inspection device 10 through the light receiving unit 152.

[0085] The spatial light modulator 120 may modulate the light L received from the light source. The spatial light modulator 110 may include any device capable of changing the amplitude or phase information of the incident light according to the position. The spatial light modulator 110 may be a device that forms a light image in a three-dimensional space and controls the spatial distribution of light by controlling the spatial distribution of light.

[0086] The spatial light modulator 110 may modulate the light received from the light source so that the light has a plurality of focal points. The light irradiation unit 100 may irradiate a plurality of lights having a plurality of focal points onto the surface of the measuring object 20. Figure 5 and Figure 6 In FIG. 1 , a single light having a single focus is shown to be irradiated onto the surface of the measurement object 20, but this is for the convenience of description, as with Figure 7 An embodiment of the spatial light modulator described below may irradiate a plurality of lights having a plurality of focal points onto the surface of the measurement object 20 using a plurality of digital micromirror devices (DMDs).

[0087] The optical system may refract light at multiple wavelengths using chromatic aberration. The optical system may refract light at multiple wavelengths with different refractive indices. The optical system may refract each light modulated in the spatial light modulator 110. The optical system may form a measurement interval where the light refracted at the wavelength is focused by refracting light having multiple wavelengths at different refractive indices. The measurement interval may be formed in the up and down directions. Figure 5 and Figure 6 In FIG. 1 , a single light having a single focus is shown to be irradiated onto the surface of the measurement object 20, but as shown in FIG. Figure 1 As shown, the modulated light can be refracted by the optical system so that the light L received from the light source is refracted at different refractive indices according to multiple wavelengths, thereby forming measurement intervals in the up and down directions.

[0088] The optical system may include a plurality of lenses 211, 212, 213, 214, 215, 241. The lens may include any optical device that gathers or diverges light by refracting received light. The lens may include a variable lens 241 whose curvature can be adjusted. The variable lens 241 will be described later together with the focus adjustment unit 240 described later.

[0089] The three-dimensional shape inspection device 10 may include a reflecting portion 220 that reflects light to change a moving path of the light. The reflecting portion 220 may include an optical device that transmits the light to a different path by reflecting received light.

[0090] The three-dimensional shape inspection device 10 may include a light splitter 230 that reflects a portion of light and transmits another portion of light to divide the moving path of light into two paths. The light splitter 230 may transmit a portion of light reflected by the measuring object. The light splitter 230 may reflect another portion of light reflected by the measuring object.

[0091] The image sensor 400 may detect color information of light. The image sensor 400 may detect light reflected by the measuring object 20. The image sensor 400 may detect light focused and reflected at a position corresponding to a height on the surface of the measuring object 20, among the light refracted by wavelength reflected by the measuring object 20. The height on the surface may be a height of the base 22 or the transparent body 24 of the measuring object 20. The image sensor 400 may detect color information of a plurality of lights focused and reflected on the surface of the measuring object 20.

[0092] In one embodiment, the three-dimensional shape inspection device 10 may include a control unit for measuring the height of the surface of the measurement object 20. The control unit may include a computer storing programs and / or information. The control unit may measure the height of the measurement object 20 based on the color information detected by the image sensor 400. The height of the measurement object 20 that reflects multiple lights may be measured based on the color information of multiple lights detected by the image sensor 400. The image sensor 400 may measure each height on the surface of the measurement object 20 that reflects multiple lights. The image sensor 400 of the three-dimensional shape inspection device 10 of the present disclosure can measure the heights on multiple surfaces of the measurement object 20 at one time, which has the effect of being able to perform high-speed large-area inspection of the measurement object.

[0093] Figure 7 is a schematic diagram showing a digital micromirror device used in an embodiment of the present disclosure. Figure 7 , a digital micromirror device (DMD) as an example of the spatial light modulator 110 according to an embodiment of the present disclosure is described.

[0094] The spatial light modulator 110 may include a digital micromirror device (DMD) using digital light processing (DLP) technology. The digital micromirror device (DMD) may include a plurality of digital micromirror devices (DMDs) arranged in an array. The digital micromirror device (DMD) may be a micro-sized mirror made using a micro-electromechanical system (MEMS). That is, each of the plurality of digital micromirror devices (DMDs) may function as a pixel. Figure 6 The digital micromirror devices (DMDs) of FIG. 1 form an array of 18 rows and 19 columns, but the number of rows and columns constituting the array is exemplary and may have any other number of columns and rows.

[0095] The digital micromirror device (DMD) has electrodes at the bottom that can receive electrical signals from the outside, and a reflector at the top that can reflect light. By applying electrical signals to the electrodes at the bottom of the digital micromirror device (DMD) to adjust the angle of the reflector, the reflected light is reflected to an external projection lens (not shown) and emitted, or is reflected to a light absorbing plate (not shown) and not emitted and absorbed. By adjusting the electrodes at the bottom of the digital micromirror device (DMD), the light of an independent digital micromirror device (DMD) can be adjusted to an on / off state. Since the spatial light modulator 110 can adjust each pixel of the digital micromirror device (DMD) to an on / off state, it can modulate the light L received from the light source into light having a desired shape and form. Figure 7In the figure, the digital micromirror devices of the 4n+1 rows and 4n+1 columns of the array are shown to be in the on state (n is an integer greater than 0), but the present disclosure is not limited to this, and the digital micromirror devices of the elements of each array can be arbitrarily adjusted to the on / off state.

[0096] Reference Figures 5 to 7 , the light irradiation unit 100 may irradiate a plurality of lights downward onto the surface of the measuring object 20 in a horizontal direction perpendicular to the up-down direction. Each of the plurality of digital micromirror devices (DMDs) may be adjusted to an on / off state, and light reflected from the digital micromirror device (DMD) in the on state may be emitted to the measuring object 20. Therefore, the plurality of lights emitted and modulated from each of the plurality of digital micromirror devices (DMDs) may have a plurality of focal points. The three-dimensional shape inspection device 10 of an embodiment of the present disclosure may irradiate a plurality of lights having a plurality of focal points onto the surface of the measuring object 20.

[0097] Figure 8 is a schematic diagram showing a charge coupled device (CCD) used in an embodiment of the present disclosure. Fig. 9 3 is a schematic diagram showing a process of obtaining RGB information of light by a 3-charge coupled device according to an embodiment of the present disclosure. Fig.10 It shows that Figure 8 Conceptual diagram of the process of converting the RGB information obtained in the image into the HSV coordinate system.

[0098] In reference Figure 8 In one embodiment, the image sensor may include a charge coupled device (CCD). A charge coupled device (CCD) may refer to a sensor that converts light into electric charge to obtain information about the light. A charge coupled device (CCD) is composed of a chip in the form of a pixel, and a photodiode that generates electrons according to the number of photons is arranged inside. By measuring and reconstructing the amount of electrons or current, the intensity information of the light can be obtained.

[0099] The charge coupled device (CCD) may include a plurality of charge coupled devices (CCDs) arranged in an array. Each charge coupled device (CCD) may function as a pixel. The plurality of charge coupled devices (CCDs) may detect color information of a plurality of reflected lights that are focused and reflected on the surface of the measuring object 20 by modulated lights having a plurality of focal points. Based on the color information of the plurality of lights detected by the charge coupled device (CCD), each height on the surface of the measuring object 20 that reflects the plurality of lights may be measured.

[0100] The charge coupled device (CCD) may be a 1-charge coupled device (1CCD) consisting of one charge coupled device, or a 3-charge coupled device (Three Charged Coupled Device, hereinafter referred to as 3CCD) having three independent charge coupled devices. Fig. 9 , the 3-charge coupled device (3CCD) may include 3 independent charge coupled devices (3CCD-R, 3CCD-G, 3CCD-B). The 3 independent charge coupled devices (3CCD-R, 3CCD-G, 3CCD-B) are respectively located on the path of the light separated into R, G, and B components from prisms A, B, and C, so that the R, G, and B components of the light can be detected. The 3-charge coupled device (3CCD) detects the R, G, and B components separated from prisms A, B, and C using each charge coupled device, and can provide higher color reproducibility and image quality compared to the 1-charge coupled device (1CCD) method.

[0101] In other embodiments not shown, the image sensor 400 may include a complementary metal oxide semiconductor (CMOS). The CMOS may be composed of a plurality of pixels. Light reaching each pixel may be focused on a photodiode to generate electrons, and the generated electrons may be converted into a voltage form to detect light information.

[0102] The image sensor 400 may include any one of a color camera, a multispectral camera, or a monochrome camera with a bandpass filter. The image sensor 400 of the present disclosure is not limited thereto, but includes all devices capable of detecting RGB information of light.

[0103] The color information of the light detected by the image sensor 400 may include RGB information. For example, the color information of the light detected by a 3-charge coupled device (3CCD) of the image sensor 400 may include RGB information. The RGB information may be RGB information of light focused and reflected at a position corresponding to a height on the surface of the measuring object 20, among the light refracted by wavelength.

[0104] The image sensor 400 may obtain wavelength information of light based on the detected RGB information.

[0105] In an embodiment not shown, by creating a look-up table that tabulates wavelength information corresponding to RGB information in advance, the RGB information detected by the image sensor 400 can be converted into wavelength information of light.

[0106] 102 in reference Fig.10In another embodiment, the image sensor 400 may convert the RGB information into another coordinate system to obtain the wavelength information of the light focused and reflected on the surface of the measuring object 20. The other coordinate system may be an HSV coordinate system or a CIE XYZ coordinate system. For example, the RGB information detected by the image sensor 400 may be converted to the HSV coordinate system through the following mathematical formulas 1, 2, and 3, so that the wavelength information of the light may be obtained through the HSV information. H is a value indicating hue (Hue), having a value of 0° to 360°, and 0° and 360° may represent the hue of red. S is a value indicating saturation (Saturation), assuming that when the most vivid state is 100%, 0% may represent an achromatic color of the same brightness. V is a value indicating value (Value), which may represent the brightness when white is 100% and black is 0%. Since the wavelength information of the light source corresponding to the H value of the light source is a predetermined value (for example, when H is 0° or 360°, the wavelength of red light is 625nm to 740nm), the wavelength information of the light source can be detected by the H value obtained by HSV coordinate system conversion.

[0107]

Mathematical formula 1

[0108] H=θ(if B≤G)

[0109] =360-θ(if B≥G)

[0110]

[0111]

Mathematical formula 2

[0112]

[0113]

Mathematical formula 3

[0114]

[0115] In addition, in the CIE chromaticity diagram obtained by converting RGB information into the CIE XYZ coordinate system, the dominant wavelength (Dominant Wavelength) as the wavelength of monochromatic light whose position is closest to the chromaticity coordinates of the light source can be detected. The above-mentioned HSV coordinate system and CIE XYZ coordinate system are merely examples for describing the present disclosure, and all coordinate systems that can obtain wavelength information of light can be used.

[0116] Fig.11 Schematic diagram showing the operating state of the three-dimensional shape inspection device according to an embodiment of the present disclosure. Fig.12 Is a description Fig.11 A diagram showing the operation of the filter that blocks light above a certain wavelength. Figure 5 , Figure 6 , Fig.11 and Fig.12 , the inspection method of the three-dimensional shape inspection device 10 of the present invention is described as follows.

[0117] Reference Fig.11 , the spatial light modulator 110 modulates the light L received from the light source and irradiates the light onto the surface of the measuring object 20. An optical system for transmitting light may be arranged on the path before the light is irradiated from the spatial light modulator 110 to the measuring object 20. For example, the optical system may include a plurality of lenses 211, 212, 214, 241 arranged on the path. A light separator 231 may be arranged on the path of the light irradiated from the spatial light modulator 110 to the measuring object 20. The light separator 231 may form a light path from the spatial light modulator 110 to the measuring object 20 by reflecting the received light. The optical system may include a lens 242 (not shown) located before irradiating the measuring object 20. The lens 242 may be composed of a plurality of lenses. The lens 242 may be an objective lens. The light reflected from the surface of the measuring object 20 is transmitted to the image sensor 400. The image sensor 400 may include a first detection unit 410 and a second detection unit 420.

[0118] An optical system for transmitting light may be arranged on a path from the light reflected from the measuring object 20 to the first detecting part 410. An optical system for transmitting light may be arranged on a path from the light reflected from the measuring object 20 to the second detecting part 420. For example, the optical system may include a plurality of lenses 241, 214, 212, 215 arranged on a path to the first detecting part 410. In addition, the optical system may include a plurality of lenses 241, 214, 212, 216 arranged on a path to the second detecting part 420. An optical splitter 231 may be arranged on a path from the measuring object 20 to the first detecting part 410 or the second detecting part 420. The optical splitter 231 may form an optical path from the measuring object 20 to the first detecting part 410 or the second detecting part 420 by transmitting the received light.

[0119] The three-dimensional shape inspection device 10 may include an optical splitter 232 disposed on a path of light traveling from the optical splitter 231 to the first detection unit 410 or the second detection unit 420. The optical splitter 232 may transmit a portion of light reflected from the measurement object 20, and may reflect another portion of light reflected from the measurement object 20. The optical splitter 232 may form an optical path from the optical splitter 231 to the first detection unit 410 by transmitting received light. Information of light transmitted through the optical splitter 232 may be detected by the first detection unit 410. The optical splitter 232 may form an optical path from the optical splitter 231 to the second detection unit 420 by reflecting received light. Information of light reflected by the optical splitter 232 may be detected by the second detection unit 420.

[0120] The first detection unit 410 and the second detection unit 420 can measure the height of the measuring object 20 by detecting information of light focused and reflected at a position corresponding to the height on the surface of the measuring object 20 in the light refracted by wavelength. The light information may be wavelength information of the light. The first detection unit 410 and the second detection unit 420 can detect color information of light focused and reflected at a position corresponding to the height of the base 22 of the measuring object 20 or the height of the transparent body 24 arranged on the base 22 in the light refracted by wavelength.

[0121] In one embodiment, the three-dimensional shape inspection device 10 may include a control unit that measures the height of a base of the measurement object and the height of a transparent body disposed on the base based on information detected by the first detection unit and information detected by the second detection unit.

[0122] The light path formed in such a manner that the light L emitted from the light source can be reflected at the measuring object 20 and transmitted to the first detection unit 410 or the second detection unit 420 is not limited thereto, and any light path can be formed by arranging lenses, the reflection unit 220 and the optical splitters 231 and 232 .

[0123] The three-dimensional shape inspection device 10 may include a focus adjustment unit that can change the measurement interval by changing the position where the light refracted by the optical system according to the wavelength is focused in the up-down direction. For example, according to the embodiments described later, the focus adjustment unit can be implemented by a device that can change the position of the optical system, or by a device that constitutes a part of the optical system and can change the light focusing position.

[0124] The focus adjustment unit can change the position where the light refracted by wavelength is focused. The focus adjustment unit can change the position where the light is focused in the up-down direction. The focus adjustment unit can change the measurement interval where the light refracted by wavelength is focused. The focus adjustment unit can change the point where the light with the shortest wavelength among the light refracted by wavelength is focused in the up-down direction. The focus adjustment unit can change the point where the light with the longest wavelength among the light refracted by wavelength is focused in the up-down direction. The focus adjustment unit can change the point where the light with a wavelength between the shortest wavelength and the longest wavelength among the light refracted by wavelength is focused in the up-down direction.

[0125] In an embodiment not shown in the figure, the focus adjustment unit may be operated by a mechanical device that adjusts the position of the optical system to change the measurement interval. The focus adjustment unit may be able to change the measurement interval by moving the optical system in the up and down direction.

[0126] In reference Fig.11 In other embodiments, the focus adjustment unit 240 may constitute a part of the optical system. Fig.11 The illustrated embodiment is described as a reference.

[0127] The optical system may include a focus adjustment unit 240. The focus adjustment unit 240 may be operated using an electronic device that changes the measurement interval by applying an electric current or the like. The focus adjustment unit 240 may include a variable lens 241 that can change the measurement interval based on the applied electric current. In the present disclosure, the focus adjustment unit 240 is shown to be arranged on a light path immediately before being irradiated to the measurement object 20, but it is not limited thereto, and the focus adjustment unit 240 may be arranged on any path on the light path from the light source to the first detection unit 410 and the second detection unit 420.

[0128] Reference Fig.12 , the filter section 430 for blocking light above a specific wavelength is described.

[0129] Either the first detection unit 410 or the second detection unit 420 may be a filter detection unit. The filter detection unit may include a filter unit 430 that blocks light above a specific wavelength (λ0). For example, a specific wavelength such as Fig.12As shown, it can be any wavelength (λ0). The filtering detection unit can detect information of light that does not reach a specific wavelength (λ0). The present disclosure is described based on the situation that the second detection unit 420 is a filtering detection unit and the second detection unit 420 includes a filtering unit 430, but the present disclosure is not limited to this. An embodiment may also be that the first detection unit 410 is a filtering detection unit including a filtering unit. The present disclosure shows an embodiment in which the filtering unit 430 is arranged on the light path toward the second detection unit 420, but the present disclosure is not limited to this. The filtering unit 43 includes an optical filter arranged on the light path and operated by a mechanical device, or an optical filter that is not arranged on the light path but operated by an electronic device. The optical filter may be a short pass filter.

[0130] The first detection unit and the second detection unit can detect the intensity information of the light. The light filter detection unit can detect the intensity information of the light.

[0131] Fig.13 1 is a schematic diagram showing light focused and reflected at a position corresponding to the height of the base of the measurement object or the height of a transparent body arranged on the base, among the light refracted by the optical system according to the wavelength. Fig.14 This is a graph showing a case where the intensity information of light detected by the light filter detection unit is determined to be equal to or less than a predetermined first specific intensity. Fig.15 This is a graph showing a case where the intensity information of light detected by the light filter detection unit is determined to be equal to or higher than a predetermined second specific intensity. Fig.16 This is a graph showing a case where the intensity information of light detected by the light filter detection unit satisfies a predetermined standard.

[0132] Reference Fig.13 and Fig.16 , describing the inspection method of the three-dimensional shape inspection device when the measurement object 20 includes a transparent body 24.

[0133] When the measuring object 20 includes the base 22 and the transparent body 24 , among the light refracted by the optical system by wavelength, there may be light focused at a position corresponding to the height of the base 22 or the height of the transparent body 24 . Figures 13 to 16 λ1 shown is defined as the wavelength of light focused at a position corresponding to the height of the transparent body 24 , and λ2 is defined as the wavelength of light focused at a position corresponding to the height of the base 22 .

[0134] The first detection section 410 and the second detection section 420 can detect wavelength information of light focused and reflected at a position corresponding to the height of the base 22 of the measurement object 20 or the height of the transparent body 24 arranged on the base 22, among the light refracted by wavelength. The filter detection section as either the first detection section 410 or the second detection section 420 can detect information of light that does not reach the specific wavelength (λ0) by means of the filter section 430 that blocks light above the specific wavelength (λ0).

[0135] Reference Figures 14 to 16 , Figures 14 to 16 (a) may be a graph showing information on light detected by a non-filter detection unit that is not a filter detection unit in the first detection unit and the second detection unit. Figures 14 to 16 (b) may be a graph showing information of light detected by the light filtering detection section in the first detection section and the second detection section. Figures 14 to 16 (c) may be a graph showing information of light detected by both the light filtering detection section and the light non-filtering detection section.

[0136] Reference Figures 14 to 16 (a), the non-filtered detection portion can detect the wavelength (λ1) of the light focused and reflected at the position corresponding to the height of the transparent body 24 and the wavelength (λ2) of the light focused and reflected at the position corresponding to the height of the base 22. The intensity of the wavelength (λ2) of the light focused and reflected at the position corresponding to the height of the base 22 and the intensity of the wavelength (λ1) of the light focused and reflected at the position corresponding to the height of the transparent body 24 detected by the non-filtered detection portion may be different. In the present disclosure, the intensity of the wavelength (λ1) of the light focused and reflected at the position corresponding to the height of the transparent body 24 has a very small value and is Figures 14 to 16 The description is made based on an embodiment not shown in (a), but the present disclosure is not limited thereto.

[0137] Depending on the wavelength (λ1) of light focused at a position corresponding to the height of the transparent body 24, the wavelength (λ2) of light focused at a position corresponding to the height of the base 22, and the size of the specific wavelength value of the filter portion, there may be three situations such as (1) λ0<λ1<λ2, (2) λ1<λ2<λ0, and (3) λ1<λ0<λ2.

[0138] Reference Fig.14 , the case 1 is described. The light focused and reflected at the position corresponding to the height of the base 22 of the measuring object 20 or the height of the transparent body 24 all has a wavelength greater than the specific wavelength (λ0). The filter detection unit includes a filter unit 430 that blocks light above the specific wavelength (λ0), so the light focused and reflected at the position corresponding to the height of the base 22 of the measuring object 20 or the height of the transparent body 24 can be blocked by the filter unit 430 (refer to Fig.14 (b)). Observe the graph showing the information of light detected by the light-filtering detection unit and the light-unfiltering detection unit (reference Fig.14 (c)), only the information of one wavelength (λ2) focused and reflected on the base surface can be detected, so the measurement object 20 cannot be inspected.

[0139] Reference Fig.15 , the case 2 is described. The light focused and reflected at the position corresponding to the height of the base 22 of the measuring object 20 or the height of the transparent body 24 has a wavelength smaller than the specific wavelength (λ0). The filter detection unit includes a filter 430 that blocks light above the specific wavelength (λ0), so the light focused and reflected at the position corresponding to the height of the base 22 of the measuring object 20 and the height of the transparent body 24 may not be blocked by the filter 430 (compare Fig.15 (b)). Observe the graph showing the information of light detected by the light-filtering detection unit and the light-unfiltering detection unit (reference Fig.15 (c)), the filter detection unit detects the information of the two wavelengths (λ1, λ2) that are not blocked by the filter unit 430, and thus can detect the information of the light of the wavelength (λmix) formed by the mixture of the two wavelengths (λ1, λ2). The mixed wavelength (λmix) is a mixture of the information of the two wavelengths (λ1, λ2), and the intensity value of the light corresponding to the mixed wavelength (λmix) may have an intensity greater than a specific saturation intensity (S). Since the wavelength (λmix) formed by the mixture of the wavelength information of the light detected by the filter detection unit and the non-filter detection unit is included, the height corresponding to the specific wavelength cannot be measured, and thus the measurement object 20 cannot be inspected.

[0140] Reference Fig.16 , situation 3 is described. The wavelength (λ2) of the light focused and reflected at the position corresponding to the height of the base 22 of the measuring object 20 will be greater than the specific wavelength (λ0), and the wavelength (λ1) of the light focused and reflected at the position corresponding to the height of the transparent body 24 will be less than the specific wavelength (λ0). The filter detection unit includes a filter unit 430 that blocks light above the specific wavelength (λ0), so that the light focused and reflected at the position corresponding to the height of the base 22 of the measuring object 20 can be blocked by the filter unit 430. For example, the filter detection unit can block the light focused and reflected at the position corresponding to the height of the base 22 and detect the information of the wavelength (λ1) of the light focused and reflected at the position corresponding to the height of the transparent body 24 (refer to Fig.16 (b)). Observe the graph showing the information of light detected in the light-filtering detection section and the light-unfiltering detection section (refer to Fig.16(c)) can be inspected based on the wavelength (λ2) information of the light focused and reflected at the position corresponding to the height of the base 22 detected by the non-filtering detection unit and the wavelength (λ1) information of the light focused and reflected at the position corresponding to the height of the transparent body 24 detected by the filtering detection unit.

[0141] exist Fig.14 In the case 1, the control unit may determine that the intensity information of the light detected by the filter detection unit is less than the predetermined first specific intensity. The predetermined first specific intensity may be any very small value. When the control unit determines that the intensity information of the light detected by the filter detection unit is less than the predetermined first specific intensity, the control unit may control the focus adjustment unit 240 to change the measurement interval. The control unit may change the measurement interval by controlling the focus adjustment unit 240 so that it becomes the condition of the case 3.

[0142] When it is determined that the light intensity information is below the predetermined first specific intensity, the control unit may control the focus adjustment unit 240 to change the measurement interval so that the measurement object 20 reflects light with a shorter wavelength. When it is determined that the light intensity information is below the predetermined first specific intensity, the control unit may control the focus adjustment unit 240 to change the measurement interval so that the transparent body 24 reflects light with a shorter wavelength. When the control unit determines that the light intensity information is below the predetermined first specific intensity, the focus adjustment unit 240 may be controlled to move the measurement interval downward so that the transparent body 24 reflects light with a shorter wavelength. When the control unit determines that the light intensity information is below the predetermined first specific intensity, the focus adjustment unit 240 may be controlled to move the measurement interval downward so that the transparent body 24 reflects light with a wavelength shorter than the specific wavelength (λ0). When the control unit determines that the light intensity information is below the predetermined first specific intensity, the focus adjustment unit 240 may be controlled to move the measurement interval downward until the base 22 reflects light with a wavelength greater than the specific wavelength (λ0).

[0143] exist Fig.15 In the case 2, the control unit may determine that the intensity information of the light detected by the filter detection unit is greater than the predetermined second specific intensity (S). The predetermined second specific intensity may be an arbitrary value. When the control unit determines that the intensity information of the light detected by the filter detection unit is greater than the predetermined second specific intensity, the control unit may control the focus adjustment unit 240 to change the measurement interval. The control unit may change the measurement interval by controlling the focus adjustment unit 240 so as to meet the conditions of the case 3.

[0144] When the control unit determines that the intensity information of the light is above the predetermined second specific intensity, the focus adjustment unit 240 may be controlled to change the measurement interval so that the measurement object 20 reflects light with a longer wavelength. When the intensity information of the light is determined to be above the predetermined second specific intensity, the control unit may control the focus adjustment unit 240 to change the measurement interval so that the base 22 reflects light with a longer wavelength. When the intensity information of the light is determined to be above the predetermined second specific intensity, the control unit may control the focus adjustment unit 240 to move the measurement interval upward so that the transparent body 24 reflects light with a longer wavelength. When the intensity information of the light is determined to be above the predetermined second specific intensity, the control unit may control the focus adjustment unit 240 to move the measurement interval upward so that the base 22 reflects light with a wavelength longer than the specific wavelength (λ0). When the intensity information of the light is determined to be above the predetermined second specific intensity, the control unit may control the focus adjustment unit 240 to move the measurement interval upward until the transparent body 24 reflects light with a wavelength less than the specific wavelength (λ0).

[0145] exist Fig.16 In case 3, when the light intensity information is above the first specific intensity and below the second specific intensity, the control unit may determine that the predetermined reference is met. When the light intensity information is below the first specific intensity or above the second specific intensity, the control unit may determine that the predetermined reference is not met.

[0146] Fig.17 1 is a schematic diagram showing that the three-dimensional shape inspection device according to an embodiment of the present disclosure can perform inspection regardless of the shapes of the base and the transparent body.

[0147] Reference Figure 4 and Fig.17 , Figure 4 The three-dimensional shape inspection device 50 of the comparative embodiment does not include a separate focus adjustment unit, so there is a problem that it cannot be inspected according to the shape of the sample. However, the three-dimensional shape inspection device 10 of an embodiment of the present disclosure includes a focus adjustment unit 240, so that the measurement interval can be changed by changing the focus position of the light refracted by the wavelength in the up and down directions.

[0148] like Fig.17 As shown in (a), in general, not only when there is a wavelength (λ11, λ12) of light focused and reflected at a position corresponding to the height of the base 22 or the height of the transparent body 24 in the light refracted by wavelength, but also when Fig.17 (b) shows a sample in which the base 22 is very thick, and Fig.17 Even in the case where the transparent body 24 is a very thick sample as shown in (c), the focus adjustment unit 240 can be used to change the measurement interval in the vertical direction to enable inspection. Figure 4In the case shown in (b), the focus adjustment unit 240 can be used to change the measurement interval in the upward direction to detect Fig.17 (b) shows information on the wavelengths (λ21, λ22) of light focused and reflected at a position corresponding to the height of the base 22 or the height of the transparent body 24. Figure 4 In the case shown in (c), the focus adjustment unit 240 can be used to change the measurement interval in the downward direction to detect Fig.17 (c) shows information on the wavelength (λ31, λ32) of light focused and reflected at a position corresponding to the height of the base 22 or the height of the transparent body 24.

[0149] Fig.18 1 is a schematic diagram for describing a manner in which a three-dimensional shape inspection apparatus according to an embodiment of the present disclosure measures a height of a base of a measurement object and a height of a transparent body arranged on the base. Fig.19 : is a graph showing the inherent focus shift values ​​of each wavelength of the optical system according to an embodiment of the present disclosure.

[0150] Reference Fig.18 , when the light intensity information satisfies Fig.16 When the predetermined reference of situation 3 is met, the control unit can control the focus adjustment unit 240 to change the measurement interval. The first state before the predetermined reference is met and the measurement interval is changed is Fig.18 (a) shows that the second state after satisfying the predetermined criterion and changing the measurement interval is Fig.18 The first detection unit 410 and the second detection unit 420 may detect the wavelength information of the light again in a state where the measurement interval has been changed. The first detection unit 410 and the second detection unit 420 may detect the wavelength (λ3, λ4) information of the light focused and reflected at the base 22 and the transparent body 24 in a state where the measurement interval has been changed.

[0151] The control unit may obtain, in the first state before changing the measurement interval, the first information detected by the non-filtered detection unit of the first detection unit 410 and the second detection unit 420, which is not the filtered detection unit, and obtain the second information detected by the filtered detection unit. The first information may be the wavelength (λ1) information of the light focused and reflected at the base 22. The second information may be the wavelength (λ2) information of the light focused and reflected at the transparent body 24. The control unit may obtain, in the second state after changing the measurement interval, the third information detected by the non-filtered detection unit and the fourth information detected by the filtered detection unit. The present disclosure is described based on the fact that the measurement interval is changed in the upward direction in the first state to become the second state, but the present disclosure is not limited thereto, and may also be an embodiment in which the measurement interval is changed in the downward direction to become the second state. The third information may be the wavelength (λ3) information of the light focused and reflected at the base 22. The fourth information may be the wavelength (λ4) information of the light focused and reflected at the transparent body 24. The wavelength (λ3) of the third information may be greater than the wavelength (λ1) of the first information. The wavelength (λ4) of the fourth information may be greater than the wavelength (λ2) of the second information. In the present disclosure, the description is based on the non-filtering detection part being the first detection part 410 and the filtering detection part being the second detection part 420, but the present disclosure is not limited to this, and an embodiment in which the non-filtering detection part is the second detection part 420 and the filtering detection part is the first detection part 410 may also be adopted.

[0152] The control part may measure the height of the base 22 of the measurement object 20 and the height of the transparent body 24 disposed on the base 22 based on the first information, the second information, the third information, the fourth information, and the refractive index.

[0153] The control unit can measure the height of the base 22 of the measurement object and the height of the transparent body 24 arranged on the base 22 based on the first information, the second information, the third information and the fourth information. The control unit can measure the refractive index (n) of the transparent body based on the working distance in the first state, the working distance in the second state, the first information and the third information. The working distance can be defined as a value proportional to the average value of the distance from the optical system to the focus position of the light refracted by the wavelength. That is, as the average distance from the optical system to the location where the light refracted by the wavelength is focused changes with the help of the focus adjustment unit 240, the working distance will also change. For example, if Fig.18 As shown, the second state may be a state in which the average distance from the optical system to the location where the light refracted by the wavelength is focused is smaller than the first state. The working distance (WD2) in the second state may be smaller than the working distance (WD1) in the first state. The working distance may be a value that increases according to the current applied to the focus adjustment unit 240.

[0154] The optical system can have an inherent focus shift value for each wavelength according to chromatic aberration (Chromatic FocalShift, see Fig.19). Optical systems have inherent focus shift values ​​according to their respective design methods. The inherent focus shift value caused by chromatic aberration can be a value that quantifies the degree of change in the position of the focus of each optical system focusing multiple wavelengths as a measure of chromatic aberration.

[0155] The working distance (WD1) in the first state, the working distance (WD2) in the second state, and the focal shift value (Chromatic Focal Shift) inherent to each wavelength satisfy the following equations 4, 5, and 6. Equation 6 is a equation obtained by performing an identity transformation on the refractive index (n) of the transparent body in equation 5.

[0156] Referring to Mathematical Formula 4, the value obtained by subtracting the second focus shift value (Focal shift (λ1)) corresponding to the second information from the fourth focus shift value (Focal shift (λ4)) corresponding to the fourth information may be the value obtained by subtracting the working distance (WD2) in the second state from the working distance (WD1) in the first state. Referring to Mathematical Formula 5, the value obtained by multiplying the value obtained by subtracting the first focus shift value (Focal shift (λ1)) corresponding to the first information from the third focus shift value (Focal shift (λ3)) corresponding to the third information by the refractive index may be the value obtained by subtracting the working distance (WD2) in the second state from the working distance (WD1) in the first state.

[0157] 150 Referring to Mathematical Formula 6, the refractive index may be a value obtained by subtracting the working distance (WD2) in the second state from the working distance (WD1) in the first state, divided by a value obtained by subtracting the first focus shift value (Focal shift (λ1)) from the third focus shift value (Focal shift (λ3)), wherein the third focus shift value corresponds to the third information and the first focus shift value corresponds to the first information. The greater the current applied to the focus adjustment unit 240, the greater the value obtained by subtracting the working distance (WD2) in the second state from the working distance (WD1) in the first state. That is, by tabulating the value of the working distance corresponding to the current applied to the focus adjustment unit 240, the value obtained by subtracting the working distance (WD2) in the second state from the working distance (WD1) in the first state can be obtained based on the value of the current applied to the focus adjustment unit 240.

[0158]

Mathematical formula 4

[0159] Focal shift(λ 4 )-Focal shift(λ 2 )=WD 1 -WD 2

[0160]

Mathematical formula 5

[0161] [Focal shift(λ 3 )-Focal shift(λ 1 )]×n=WD 1 -WD 2

[0162]

Mathematical formula 6

[0163]

[0164] Fig. 20 This is a flowchart showing the flow of one embodiment of the three-dimensional shape inspection method of the present disclosure.

[0165] Reference Figure 5 , Figure 6 , Fig.11 and Fig. 20 The three-dimensional shape inspection method S10 may include a white light irradiation step S101, a DLP multiple pattern irradiation step S102, a measurement object irradiation step S103, and a reflection step S104 of a wavelength signal corresponding to the height of the measurement object.

[0166] The white light irradiation step S101 is a step of irradiating light L from a light source to irradiate onto the surface of the measuring object 20. The DLP multiple pattern irradiation step S102 may be a step of modulating the light received in the white light irradiation step S101. The DLP multiple pattern irradiation step S102 may modulate the light L received from the light source so as to irradiate multiple lights having multiple focal points onto the surface of the measuring object 20. In the DLP multiple pattern irradiation step S102, light modulation may be performed by the spatial light modulator 110. The DLP multiple pattern irradiation step S102 may correspond to a light modulation step.

[0167] The measurement object irradiation step S103 may irradiate each light modulated in the DLP multiple pattern irradiation step S102 downward so that it is refracted at different refractive indices according to multiple wavelengths according to chromatic aberration, thereby forming a measurement interval in the upper and lower directions where the light refracted according to the wavelength is focused. In the measurement object irradiation step S103, the modulated light may form the measurement interval by an optical system. The measurement object irradiation step S103 may correspond to the light irradiation step.

[0168] The reflection step S104 of the wavelength signal corresponding to the height of the measuring object may be a step in which, among the wavelength-refracted light irradiated to the measuring object in the measuring object irradiation step S103 , light focused at a position corresponding to the height on the surface of the measuring object 20 is reflected.

[0169] The three-dimensional shape inspection method S10 may include: a light path forming step of transmitting a portion of the light reflected by the measuring object and reflecting another portion of the light reflected by the measuring object. The light path forming step may be performed by the optical splitter 230 .

[0170] The three-dimensional shape inspection method S10 may include: an information acquisition step of detecting color information of light focused and reflected at a position corresponding to the height on the surface of the measurement object 20, among the light refracted by wavelength in the measurement interval. The information acquisition step may include: a first detection step of detecting wavelength information of light transmitted in the light path forming step. The information acquisition step may include: a second detection step of detecting wavelength information of light reflected in the light path forming step. The first detection step and the second detection step may be performed by the first detection unit 410 and the second detection unit 420.

[0171] The information acquisition step may include an image acquisition step S105, an RGB information acquisition step S106, a coordinate system conversion step S107, and a wavelength information confirmation step S108. The first detection step and the second detection step may include an image acquisition step S105, an RGB information acquisition step S106, a coordinate system conversion step S107, and a wavelength information confirmation step S108.

[0172] The image acquisition step S105 may be a step of receiving an image or information of light focused and reflected at a position corresponding to a height on the surface of the measuring object 20. The image acquisition step S105 may receive light reflected from the measuring object 20 by the image sensor 400. The RGB information acquisition step S106 may be a step of obtaining RGB information of the light received in the image acquisition step S105. The RGB information acquisition step S106 may obtain RGB information of the light by a 3-charge coupled device (3CCD) of the image sensor 400.

[0173] The coordinate system conversion step S107 may include the step of converting the RGB information obtained in the RGB information obtaining step S106 into another coordinate system (e.g., the HSV coordinate system or the CIE XYZ coordinate system). The wavelength information confirmation step S108 may include the step of confirming the wavelength information of the light based on the information obtained in the coordinate system conversion step S107. As described above, the wavelength information confirmation step S108 may confirm the wavelength information of the light using the H value of the HSV coordinate system or the dominant wavelength information of the CIE XYZ coordinate system.

[0174] The three-dimensional shape inspection method S10 may include: a measurement object height confirmation step S109, measuring the height of the surface of the measurement object based on the color information detected in the information acquisition step. In the measurement object height confirmation step S109, the height of the measurement object may be measured by detecting the color information of light focused and reflected at a position corresponding to the height on the surface of the measurement object 20 in the light refracted by wavelength. The light information detected in the measurement object height confirmation step S109 may be information of light focused and reflected at a position corresponding to the height on the surface of the base 22 and the transparent body 24 of the measurement object 20.

[0175] The three-dimensional shape inspection method S10 may include a three-dimensional inspection step S110 after the measurement object height confirmation step. The three-dimensional inspection step may include at least one of the steps S101 to S109, and by performing the steps S101 to S109 multiple times, inspection may be performed on multiple surfaces of the measurement object 20.

[0176] The three-dimensional shape inspection method S10 may include: a focus adjustment step of changing the measurement interval by changing the position where the light refracted by the wavelength is focused in the up-down direction. The focus adjustment step may be a step of changing the measurement interval by the focus adjustment unit 240. The focus adjustment step may be performed before the white light irradiation step S101, or before the white light irradiation step in the three-dimensional inspection step S110 performed at least once, so that the focus adjustment step may be repeated multiple times.

[0177] Fig.21 This is a flowchart showing the flow of one embodiment of the three-dimensional shape inspection method of the present disclosure when the measurement object includes a transparent object.

[0178] The three-dimensional shape inspection method S10 may include a transparent body sample arrangement step S201, a vertical scanning step S202, a predetermined reference determination step S203, a measurement interval setting step S204, a transparent body refractive index confirmation step S205, and a whole measurement object measurement step S206.

[0179] The transparent sample arrangement step S201 may be a step of arranging the transparent body 24 on the base 22. The vertical scanning step S202 may include a focus adjustment step. The vertical scanning step S202 may be a step of changing the measurement interval in the vertical direction by changing the position where the light refracted by the wavelength is focused in the vertical direction.

[0180] The predetermined reference determination step S203 may include: a first detection step of detecting wavelength information of light transmitted in the light path forming step; and a second detection step of detecting wavelength information of light reflected in the light path forming step. Either the first detection step or the second detection step may include: a light filtering detection step of blocking light above a specific wavelength and detecting information of light that does not reach the specific wavelength. The light filtering detection step may detect light intensity information.

[0181] The established reference judgment step S203 may be a step of judging that the light intensity information is below a first specific intensity or above a second specific intensity. When the established reference judgment step S203 judges that the light intensity information is below a first specific intensity or above a second specific intensity, the up-down scanning step S202 may be performed again. When the established reference judgment step S203 judges that the light intensity information is below a first specific intensity or above a second specific intensity, it may include: a focus adjustment step of changing the measurement interval by changing the position where the light refracted by the wavelength is focused in the up-down direction. In the established reference judgment step S203, when the light intensity information is below a first specific intensity, the focus adjustment step subsequently performed may include a step of moving the measurement interval downward. In the established reference judgment step S203, when the light intensity information is above a second specific intensity, the focus adjustment step subsequently performed may include a step of moving the measurement interval upward.

[0182] The measurement interval setting step S204 may be performed when the light intensity information satisfies the established reference in the established reference judgment step S203. The established reference may be a state in which the light intensity information is above an established first specific intensity and below an established second specific intensity. The measurement interval setting step S204 may include: a focus adjustment step, when the light intensity information satisfies the established reference, changing the measurement interval by changing the position where the light refracted by the wavelength is focused in the up and down directions. In the measurement interval setting step S204, the first detection step and the second detection step may be performed again in a state in which the measurement interval is changed.

[0183] The measurement interval setting step S204 can obtain the first information detected in the non-filtering detection step that is not the filtering detection step in the first detection step and the second detection step in the first state before changing the measurement interval, and obtain the second information detected in the filtering detection step. The measurement interval setting step S204 can obtain the third information detected in the non-filtering detection step and the fourth information detected in the filtering detection step in the second state after changing the measurement interval.

[0184] The transparent body refractive index confirmation step S205 can measure the refractive index (n) of the transparent body based on the working distance in the first state, the working distance in the second state, the first information, and the third information. The refractive index (n) measurement method of the transparent body refractive index confirmation step S205 can be performed in the same manner as the refractive index measurement method in the three-dimensional shape inspection device 10.

[0185] The entire measurement object measurement step S206 can measure the base height of the measurement object and the height of the transparent body arranged on the base based on the first information, second information, third information, fourth information obtained in the measurement interval setting step S204 and the refractive index measured in the transparent body refractive index confirmation step S205.

[0186] The above describes the technical concept of the present disclosure with the help of some embodiments and examples illustrated in the accompanying drawings. It should be understood that various substitutions, deformations and changes can be achieved within the limits of the technical concept and scope of the present disclosure that can be understood by ordinary technicians in the technical field to which the present disclosure belongs. In addition, such substitutions, deformations and changes should be deemed to fall within the scope of the attached claims.

Claims

1. A three-dimensional shape inspection device, comprising: a light irradiation section including a light source and a spatial light modulator configured to modulate light received from the light source so as to irradiate a plurality of lights having a plurality of focal points downward onto a surface of a measurement object; An optical system that refracts each modulated light according to a plurality of wavelengths at mutually different refractive indices according to chromatic aberration, thereby forming a measurement zone in a vertical direction for focusing the light refracted according to the wavelengths; an optical splitter that transmits a portion of the light reflected by the measuring object and reflects another portion of the light reflected by the measuring object; a first detection unit, the first detection unit detecting wavelength information of light transmitted through the optical splitter; and a second detection unit, the second detection unit detecting wavelength information of light reflected from the optical splitter; The filter detection unit as either the first detection unit or the second detection unit includes a filter unit that blocks light with a wavelength longer than a specific wavelength, and detects information on light that does not reach the specific wavelength.

2. The three-dimensional shape inspection device according to claim 1, wherein: Also includes: A control unit measures a height of a base of the measurement object and a height of a transparent body disposed on the base based on information detected by the first detection unit and information detected by the second detection unit.

3. The three-dimensional shape inspection device according to claim 1, wherein: The light filtering detection unit is configured to detect light intensity information.

4. The three-dimensional shape inspection device according to claim 3, wherein: Also includes: a focus adjustment unit configured to change the measurement interval by changing the position where the light refracted by the wavelength is focused in the up-down direction; and The control unit is configured to control the focus adjustment unit to change the measurement interval when it is determined that the intensity information of the light is equal to or less than a predetermined first specific intensity.

5. The three-dimensional shape inspection device according to claim 4, wherein: When the control unit determines that the intensity information of the light is equal to or less than a predetermined first specific intensity, the control unit controls the focus adjustment unit to change the measurement interval so that light with a shorter wavelength is reflected toward the measurement object.

6. The three-dimensional shape inspection device according to claim 3, wherein: Also includes: a focus adjustment unit configured to change the measurement interval by changing the position where the light refracted by the wavelength is focused in the up-down direction; and The control unit is configured to control the focus adjustment unit to change the measurement interval when it is determined that the intensity information of the light is equal to or greater than a predetermined second specific intensity.

7. The three-dimensional shape inspection device according to claim 6, wherein: When the control unit determines that the intensity information of the light is equal to or greater than a predetermined second specific intensity, the control unit controls the focus adjustment unit to change the measurement interval so that light with a longer wavelength is reflected toward the measurement object.

8. The three-dimensional shape inspection device according to claim 3, wherein: Also includes: a focus adjustment unit configured to change the measurement interval by changing the position where the light refracted by the wavelength is focused in the up-down direction; and a control unit, wherein the control unit controls the focus adjustment unit to change the measurement interval when the light intensity information satisfies a predetermined reference; The first detection unit and the second detection unit detect the wavelength information of light again in a state where the measurement interval is changed.

9. The three-dimensional shape inspection device according to claim 8, wherein: The control unit is configured as follows: (i) in a first state before changing the measurement interval, obtaining first information detected by a non-filtering detection section of the first detection section and the second detection section that is not the filtering detection section, and obtaining second information detected by the filtering detection section; (ii) obtaining third information detected by the non-filtered detection unit and fourth information detected by the filtered detection unit in a second state after the measurement interval is changed; (iii) Based on the first information, the second information, the third information, and the fourth information, measuring the height of the base of the measurement object and the height of the transparent body arranged on the base.

10. The three-dimensional shape inspection device according to claim 9, wherein: When a value proportional to the average value of the distance from the optical system to the focus position of the light refracted by the wavelength is defined as the working distance, The control section measures the refractive index of the transparent body based on the working distance in the first state, the working distance in the second state, the first information, and the third information.

11. The three-dimensional shape inspection device according to claim 9, wherein: The optical system has a focus shift value inherent to each wavelength according to chromatic aberration. When a value proportional to the average value of the distance from the optical system to the focus position of the light refracted by the wavelength is defined as the working distance, The control unit measures a refractive index obtained by subtracting a working distance in the second state from a working distance in the first state and dividing the refractive index by subtracting a first focus shift value corresponding to the first information from a third focus shift value corresponding to the third information.

12. The three-dimensional shape inspection device according to claim 11, wherein: The control section measures a height of a base of the measurement object and a height of a transparent body disposed on the base based on the first information, the second information, the third information, the fourth information, and the refractive index.

13. The three-dimensional shape inspection device according to claim 11, wherein: The focus adjustment unit includes: a variable lens, the variable lens being capable of changing the measurement interval based on an applied current; And the greater the applied current is, the greater the value obtained by subtracting the working distance in the second state from the working distance in the first state is.

14. The three-dimensional shape inspection device according to claim 1, wherein: The light filtering detection unit is the second detection unit.

15. The three-dimensional shape inspection device according to claim 1, wherein: The spatial light modulator comprises: A plurality of digital micromirror devices are provided, which modulate light received from the light source by reflecting the light and are arranged in an array.

16. The three-dimensional shape inspection device according to claim 1, wherein: The first detection section and the second detection section detect color information of light focused and reflected at a position corresponding to a height of a base of the measurement object or a height of a transparent body arranged on the base, among the light refracted by wavelength.

17. The three-dimensional shape inspection device according to claim 1, wherein: The light irradiation section irradiates a plurality of lights having a plurality of focal points in a horizontal direction perpendicular to an up-down direction downward onto the surface of the measuring object.

18. A three-dimensional shape inspection method, comprising: a light modulation step of modulating the light received from the light source so that a plurality of lights having a plurality of focal points are irradiated onto the surface of the measurement object; a light irradiation step of irradiating light downward so that each of the modulated lights is refracted at different refractive indices according to a plurality of wavelengths according to chromatic aberration, thereby forming a measurement interval in which the light refracted according to the wavelength is focused in the vertical direction; an optical path forming step of transmitting a portion of the light reflected by the measuring object and reflecting another portion of the light reflected by the measuring object by means of an optical splitter; A first detection step of detecting wavelength information of light transmitted in the light path forming step; and a second detection step of detecting wavelength information of the light reflected in the light path forming step; Wherein, any one of the first detection step and the second detection step comprises: The light filtering detection step blocks light with a wavelength above a specific wavelength and detects information of light that does not reach the specific wavelength.

19. The three-dimensional shape inspection method according to claim 18, wherein: The light filtering detection step detects light intensity information, It also includes: a focus adjustment step, when it is determined that the intensity information of the light is below a predetermined first specific intensity or above a predetermined second specific intensity, the measurement interval is changed by changing the focus position of the light refracted by the wavelength in the up and down directions.

20. The three-dimensional shape inspection method according to claim 18, wherein: The light filtering detection step detects light intensity information, The method further includes: a focus adjustment step, when the light intensity information satisfies a predetermined reference, changing the measurement interval by changing the focus position of the light refracted by wavelength in the up-down direction; The first detection step and the second detection step are performed again in a state where the measurement interval is changed.

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