Method and device for measuring depth of processing area of scribing workpiece

Abstract

One embodiment of the present invention provides a method for measuring the depth of a processed region of a scribe workpiece, and a method for measuring the depth of a processed region of a scribe workpiece, the method comprising: a surface image acquisition step for acquiring a surface image of an object, the surface of which is processed, from an imaging unit provided with a lens unit; a first position detection step of detecting a first position of the lens portion focused in a first region separated from the processing region on the surface image; a second position detection step of detecting a second position of the lens portion in a second region where the processing region focused on the surface image is located; and a depth measuring step of measuring the depth of the processing area by using the first position and the second position of the lens part. The first position and the second position of the lens portion are determined by a contrast ratio measured when the lens portion moves.

Description

Technical Field

[0001] The invention relates to a method for measuring the depth of a processing area of ​​a scribing workpiece and a device for measuring the depth of a processing area of ​​a scribing workpiece. Background Art

[0002] Usually in the process of producing products such as displays, a protective film is attached to the surface of the product using an adhesive (PSA) to effectively protect the surface of the product from external factors such as external contaminants and scratches, thereby improving product quality.

[0003] After the protective film is attached, in order to carry out subsequent processes, it is necessary to remove a predetermined area of ​​the protective film, and the removal of the protective film is generally completed by a scribing process using a laser.

[0004] In the process of removing the film using laser, laser processing is performed at a depth that does not damage the product under the film, specifically, cutting is performed under the condition that the adhesive under the film is maintained at a predetermined thickness.

[0005] In this case, the residual amount of the adhesive is determined by the initial thickness information of the film and the adhesive, and the residual amount can be adjusted by changing the laser output and the focal length of the processing lens.

[0006] Conventionally, in order to measure the residual amount of adhesive in a laser process, each film to be measured is cut and each cross section is confirmed one by one through a separate microscope, but at this time, it takes a lot of time to cut the film and check the depth one by one in the process. Summary of the invention

[0007] Technical Problems to be Solved by the Invention

[0008] The technical problem to be solved by the present invention is to provide a method for measuring the depth of a processing area of ​​a scribed workpiece, wherein a control unit can accurately measure the depth of a processing area formed on the surface of an object by respectively detecting the positions of lens units focused on different areas.

[0009] Technical Solution

[0010] In one aspect of the present invention, a method for measuring the depth of a processing area of ​​a scribed workpiece is provided, wherein the method comprises: a surface image acquisition step of acquiring a surface image of an object body whose surface is processed from an imaging unit provided with a lens unit; a first position detection step of detecting a first position of the lens unit focused on a first area separated from a processing area of ​​the surface image; a second position detection step of detecting a second position of the lens unit focused on a second area where the processing area is located; and a depth measurement step of measuring the depth of the processing area using the first position and the second position of the lens unit. The first position and the second position of the lens unit are determined by a contrast ratio measured when the lens unit moves.

[0011] Furthermore, the step of detecting the first position of the lens portion may further include the step of setting an area of ​​the surface image including both the first area and the second area as a first focusing area.

[0012] Furthermore, the step of detecting the first position of the lens unit may further include the step of performing a contrast autofocus operation on the first focus area to detect the position of the lens unit when the contrast of the first focus area is maximum as the first position.

[0013] Furthermore, the center of the first focusing area may coincide with the center of the processing area.

[0014] Furthermore, the step of detecting the second position of the lens portion may include the following steps: acquiring position information of the processing area; and based on the acquired position information of the processing area, setting an area of ​​the surface image as a second focusing area, and the second focusing area may be included in the second area.

[0015] Furthermore, in the step of detecting the second position of the lens unit, a contrast autofocus operation is performed on the second focus area, and a position of the lens unit when the contrast of the second focus area is maximized is detected as the second position.

[0016] Furthermore, the center of the first focusing area may coincide with the center of the second focusing area.

[0017] Furthermore, the angle between the normal vector of the surface of the object passing through the center of the processing area and the optical axis of the lens portion may be less than 5°.

[0018] Furthermore, the lens portion can move along a preset movement axis, and the movement axis can be perpendicular to the surface of the object.

[0019] Furthermore, in the step of measuring the depth of the processed area, the depth of the processed area is calculated using a difference between the first position and the second position of the lens portion.

[0020] Another aspect of the present invention provides a depth measuring device for a marking workpiece processing area, which includes: an imaging unit for acquiring a surface image of an object whose surface is being processed; a lens unit located between the imaging unit and the object, and the lens unit can move in a direction perpendicular to the surface of the object; and a control unit for controlling the lens unit, the control unit being configured to measure the contrast of the surface image acquired when the lens unit moves in the one direction.

[0021] Furthermore, the control unit can be configured to: be capable of detecting the position of the lens unit focused on a first area and the position of the lens unit focused on a second area, wherein the first area is an area separated from a processing area where processing is performed on the surface of the object, and the second area is an area where the processing area is located; and measure the depth of the processing area by using the position of the lens unit focused on the first area and the position of the lens unit focused on the second area where the processing area is located.

[0022] Beneficial Effects

[0023] The method for measuring the depth of a processed area of ​​a scribed workpiece according to an embodiment of the present invention has the following effect: by measuring the contrast by changing the focus area of ​​the imaging portion of the object, the depth of the processed area formed on the surface of the object can be measured quickly and accurately.

[0024] Furthermore, it has the following effect: by detecting defects caused by processing intensity errors due to unexpected movement of output lasers in the product production process in advance, the production yield can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 1 is an exemplary structural diagram of a device for measuring the depth of a machining area of ​​a scribing workpiece according to an embodiment of the present invention.

[0026] Figure 2 FIG. 1 is a diagram for explaining a step in which a control unit sets a first focus area and a second focus area according to an embodiment of the present invention.

[0027] FIG. 3A to FIG. 3C 1 is a diagram for explaining a step in which a control unit detects a first position of a lens unit focused on a first area according to an embodiment of the present invention.

[0028] FIG. 4A to FIG. 4C1 is a diagram for explaining a step in which a control unit detects a second position of a lens unit focused on a second area according to an embodiment of the present invention.

[0029] Figure 5 This is a diagram for explaining a step in which a control unit measures the depth of a processing region using a first position and a second position of a lens unit according to an embodiment of the present invention.

[0030] Figure 6 1 is a sequence diagram of a method for measuring the depth of a machining area of ​​a scribing workpiece according to an embodiment of the present invention.

[0031] Figure 7 is a sequence diagram of a method for detecting a first position of a lens portion according to an embodiment of the present invention.

[0032] Figure 8 FIG. 1 is a sequence diagram of a method for detecting a second position of a lens portion according to an embodiment of the present invention.

[0033] Description of Reference Numerals

[0034] 1: Processing area measuring device OB: object

[0035] G: Processing area F: Film

[0036] AD: Adhesive PN: Panel

[0037] FA1: First focus area FA2: Second focus area

[0038] CL: Center Line L: Light Source

[0039] 100: Imaging unit 110: Image sensor unit

[0040] 120: Lens unit 200: Driving unit

[0041] 300: Control unit 400: Lighting unit

[0042] 410: Light source unit 420: Mirror unit DETAILED DESCRIPTION

[0043] Since the present invention can be variously changed and can have various embodiments, specific embodiments will be shown in the drawings and described in detail in the specification. By referring to the embodiments described in detail below in conjunction with the drawings, the effects and features of the present invention and the methods for achieving them will become clear. However, the present invention is not limited to the embodiments disclosed below and can be implemented in various forms.

[0044] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. When describing with reference to the drawings, the same or corresponding constituent elements will be given the same reference numerals, and their repeated description will be omitted.

[0045] In the following embodiments, unless the context clearly dictates otherwise, an expression in a single form includes expressions in a plurality of forms.

[0046] In the following embodiments, terms such as “including” or “having” indicate that the features or constituent elements described in the specification exist, and do not exclude the possibility that one or more other features or constituent elements may be added.

[0047] When the embodiment can be implemented in other ways, a specific process sequence can be performed in a different order from the described sequence. For example, two processes described in succession can be performed substantially simultaneously, or can be performed in a reverse order to the described sequence.

[0048] In the drawings, the size of the components may be exaggerated or reduced for the convenience of explanation. For example, since the size and thickness of each component shown in the drawings are arbitrarily shown for the convenience of explanation, the following embodiments are not necessarily limited to the drawings shown.

[0049] In the description of each constituent element, when the description is formed on or under, on and under include all cases formed directly or through an intervening constituent element, and the criteria of on and under are described according to the drawings.

[0050] Figure 1 1 is an exemplary structural diagram of a device for measuring the depth of a machining area of ​​a scribing workpiece according to an embodiment of the present invention. Figure 2 FIG. 1 is a diagram for explaining a step in which a control unit sets a first focus area and a second focus area according to an embodiment of the present invention. FIG. 3A to FIG. 3C 1 is a diagram for explaining a step in which a control unit detects a first position P1 of a lens unit focused on a first area according to an embodiment of the present invention. FIG. 4A to FIG. 4C 1 is a diagram for explaining a step in which a control unit detects a second position P2 of a lens unit focused on a second area according to an embodiment of the present invention. Figure 5 1 is a diagram for explaining a step in which a control unit measures the depth of a processing region using a first position P1 and a second position P2 of a lens unit according to an embodiment of the present invention.

[0051] In the manufacturing process of products with high surface quality requirements such as display panels PN or wafers, a film F is usually attached to the surface of the product to prevent surface quality degradation due to surface contamination and crack damage.

[0052] In order to firmly fix the film F on the surface of the product, an adhesive AD is laminated between the surface of the product and the film F, and after the film F is attached, a predetermined area of ​​the film F needs to be removed for subsequent processes.

[0053] In order to remove a predetermined area of ​​the film F, the film F is cut using a laser or grinding process. At this time, the laser or grinding process is performed while leaving the adhesive AD under the film F with a predetermined thickness to prevent damage to the product surface.

[0054] In this case, in order to accurately cut the ultra-thin film F while preventing damage to the product surface, it is necessary to accurately measure the residual thickness of the adhesive AD during the cutting process. In order to accurately measure the residual thickness of the adhesive AD, it is necessary to accurately measure the depth of the processing area G formed by laser or grinding.

[0055] According to one embodiment of the present invention, a processing area depth measuring device 1 for a scribed workpiece (hereinafter referred to as "processing area depth measuring device") is a device for measuring the depth of a processing area G formed on the surface of an object OB by laser processing or grinding processing.

[0056] In the present specification, the "object body OB" may be interpreted as a panel PN to which the film F is attached. Specifically, the "object body OB" may be interpreted as a display panel PN on which an adhesive AD layer and a film F layer are sequentially stacked on the surface.

[0057] However, the present invention is not necessarily limited thereto, and the "object OB" may be interpreted as various objects having a processed region G such as a groove, a modified region, and a modified layer formed on the surface thereof by scribing processing such as laser processing or grinding processing.

[0058] For example, the “object body OB” may be interpreted as a semiconductor wafer such as a silicon wafer, a silicon on insulator (SOI) wafer, a gallium arsenide wafer, a silicon nitride wafer, etc., or may be interpreted as a glass wafer.

[0059] According to one embodiment of the present invention, a processing area depth measuring device 1 and a processing area depth measuring method can be used to measure the processing depth or the depth of a modified layer of a measuring object OB formed by a scribing process, an etching process, a stealth dicing process, a cleaving process, etc. of an object body OB such as a display panel PN, a semiconductor wafer or a glass wafer.

[0060] Reference Figure 1 , a processing area depth measuring device 1 according to an embodiment of the present invention may include an imaging part 100 , a driving part 200 , a control part 300 and an illumination part 400 .

[0061] The imaging unit 100 according to an embodiment of the present invention is used to acquire a surface image of an object OB whose surface has been processed and formed with a processing area G such as a groove, and the imaging unit 100 can output the surface image information to the control unit 300 .

[0062] In this specification, "image" can be interpreted not only as a static image but also as a dynamic image.

[0063] As an embodiment, the imaging unit 100 can detect wavelengths of red, green, and blue regions, and can generate a digital code (RGB) corresponding to the wavelength of each region. However, not limited thereto, the imaging unit 100 can detect wavelengths of various regions, and can generate a digital code corresponding to the wavelength of each region.

[0064] The imaging section 100 can amplify the electric signal and output the image information of the amplified electric signal to the control section 300. This has an effect of acquiring image information even in an external environment of low illumination.

[0065] The imaging section 100 according to one embodiment of the present invention may acquire brightness information from the surface of the object body OB. Specifically, the imaging section 100 may acquire a surface image of the object body OB, and each pixel value included in the surface image may include absolute or relative brightness information.

[0066] The brightness information of an area of ​​the surface of the object OB can be calculated by the light intensity, lux value, etc. acquired from the area by the imaging section 100, whereby the control section 300 can perform contrast autofocus operation using the brightness information of each pixel value included in the surface image.

[0067] As an optional embodiment, when the imaging unit 100 is composed of an infrared camera, the imaging unit 100 can project infrared rays. In this case, the phase difference between the projected infrared rays and the reflected infrared rays can be used to generate depth information of the target object. The period of the imaging unit 100 projecting infrared rays can be continuous or discontinuous, and the period of the imaging unit 100 projecting infrared rays can be preset.

[0068] As an optional embodiment, the imaging unit 100 can be composed of a stereo camera, and the imaging unit 100 can obtain visible light information obtained from multiple stereo cameras, and the control unit 300 can receive the obtained visible light information and generate depth information of the target object through triangulation technology.

[0069] Reference Figure 1, the imaging section 100 according to one embodiment of the present invention may include a lens section 110 and an image sensor section 120 .

[0070] The lens unit 110 is used to collect light reflected from the surface image of the object OB where the processing area G such as the groove is formed, so as to form an image on the image sensor. The lens unit 110 may be composed of various types of optical lenses.

[0071] As an embodiment, the lens portion 110 may receive power from the driving portion 200 and may be movable along a preset moving axis, and the moving axis of the lens portion 110 may be perpendicular to the surface of the object OB.

[0072] Specifically, the optical axis of the lens portion 110 may be configured to overlap with a region where the processing region G such as the groove is formed, and may be movable in a direction in which the lens portion 110 moves away from or approaches the object OB.

[0073] In this specification, the “optical axis” of the lens portion 110 may be interpreted as the symmetry axis of the lens portion 110. Specifically, the “optical axis” of the lens portion 110 may be interpreted as an axis passing through the center of the lens portion 110 and connecting the centers of curvature of the front and rear surfaces of the lens portion 110.

[0074] The moving axis of the lens portion 110 according to one embodiment of the present invention may coincide with or be parallel to the optical axis of the lens portion 110. Thus, even if the position of the lens portion 110 changes along the moving axis, the lens portion 110 may receive light from the same region of the object OB, and thus even if the lens portion 110 moves along the moving axis, the contrast ratio of the same region of the object OB may be measured.

[0075] According to an embodiment of the present invention, the angle between the optical axis of the lens unit 110 and the normal vector of the surface of the object OB may be 5° or less.

[0076] Therefore, even if the lens unit 110 moves along the moving axis, the center CL of the processing area G can always be included in the shooting area of ​​the imaging unit 100. Therefore, regardless of the position of the lens unit 110, the control unit 300 can obtain the brightness information of the center CL of the processing area G and measure the depth of the center CL of the processing area G.

[0077] The movement axis of the lens portion 110 may pass through the center CL of the groove, and may be located in the same direction as a normal vector of the surface of the object OB.

[0078] The optical axis of the lens unit 110 may be configured to be the same as the normal vector of the surface of the object OB, and the lens unit 110 receives power from the driving unit 200 and moves away from or toward the object OB along the normal vector of the surface of the object OB.

[0079] The image sensor section 120 according to one embodiment of the present invention can acquire a surface image of the object OB by receiving light received by the lens section 110 and converting it into an electric signal.

[0080] The image sensor unit 120 may receive the light received by the lens unit 110 and acquire brightness information of the surface image of the object OB in units of one or more pixels.

[0081] Specifically, when the lens unit 110 moves along the movement axis, the lens unit 110 obtains different amounts of light from various portions of the surface of the object OB, and the image sensor unit 120 can obtain brightness information of the surface image of the object OB that varies as the lens unit 110 moves.

[0082] The image sensor section 120 may transmit the brightness information of the surface image of the object OB to the control section 300 , and the control section 300 may measure the contrast using the brightness information of the surface image received from the image sensor section 120 .

[0083] Reference Figure 1 The driving part 200 according to one embodiment of the present invention may be connected to one side of the lens part 110 and provide power to move the lens part 110 along a preset moving axis.

[0084] As an embodiment, the driving unit 200 may transmit driving information to the control unit 300 , so that the control unit 300 may use the driving information of the driving unit 200 to accurately detect the position of the lens unit 110 on the moving axis.

[0085] The control section 300 according to one embodiment of the present invention may acquire a surface image of the object body OB from the imaging section 100 and measure the depth of the processing region G formed on the surface of the object body OB.

[0086] The control unit 300 can be implemented using at least one of application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, micro-controllers, microprocessors, and other electrical units for performing functions.

[0087] At least one of the control units 300 according to one embodiment of the present invention may include a volatile and / or non-volatile memory, which may store commands or data related to at least one other component of the processing area depth measuring device 1 (specifically, the driving unit 200 and the imaging unit 100).

[0088] The control unit 300 may store software and / or programs. The programs may include, for example, a kernel, middleware, an application programming interface (API), and / or an application program (or "application"), etc.

[0089] At least a portion of a kernel, middleware, or application programming interface (API) may be referred to as an operating system. For example, the kernel may control or manage resources (e.g., a bus, a processor, or a memory, etc.) used to execute actions or functions implemented in other programs (e.g., middleware, API, or application programs). Furthermore, the kernel may provide an interface for controlling or managing system resources by accessing individual components of the processing area depth measurement device 1 in the middleware, API, or application program.

[0090] Reference Figure 1 and Figure 2 , the control section 300 according to one embodiment of the present invention may set an area of ​​the surface image of the object body OB forming the processing area G as the focus area (the first focus area FA1 , the second focus area FA2 ).

[0091] In the present specification, “focus area (first focus area FA1, second focus area FA2)” may be interpreted as an area of ​​an image for which the control section 300 performs a contrast auto focus (contrast AF) action, and when an area of ​​a surface image is set as the focus area (first focus area FA1, second focus area FA2), the control section 300 may measure the contrast of the surface image based on the set focus area (first focus area FA1, second focus area FA2).

[0092] As an embodiment, the control unit 300 may receive a control command from the outside and set an area of ​​the surface image as the focus area (the first focus area FA1 , the second focus area FA2 ).

[0093] Specifically, the user can input information related to the positions of the centers C1 and C2 of the focusing areas, the sizes of the focusing areas (first focusing area FA1, second focusing area FA2), etc. into the control unit 300, and the control unit 300 can receive the geometric information of the focusing areas (first focusing area FA1, second focusing area FA2) and set an area of ​​the surface image as the focusing area (first focusing area FA1, second focusing area FA2).

[0094] As an embodiment, the control unit 300 may set an area of ​​the surface image as a focus area (a first focus area FA1 , a second focus area FA2 ) according to a preset algorithm.

[0095] Reference Figure 2 , the control unit 300 can set an area of ​​the surface image as the focus area (first focus area FA1, second focus area FA2) in a way that the centers C1 and C2 are located in the area where the processing area G is located according to a preset algorithm. Specifically, the control unit 300 can set an area of ​​the surface image as the focus area (first focus area FA1, second focus area FA2) in a way that the centers C1 and C2 overlap with the center CL of the processing area G according to a preset algorithm.

[0096] The control unit 300 can fix the centers C1 and C2 of the focus areas to the area where the center CL of the processing area G is formed according to a preset algorithm, and change the size of the focus areas (first focus area FA1 and second focus area FA2) by receiving a control command from the outside.

[0097] Specifically, the control unit 300 can fix the center C1 of the first focus area and the center C2 of the second focus area to the area where the center CL of the processing area G is located according to a preset algorithm, and receive information related to the size of the first focus area FA1 from the user to set the size of the first focus area FA1, so that the first focus area FA1 simultaneously includes the area where the processing area G is located and the surface area of ​​the object body OB (the area not where the processing area G is located), and can set the size of the second focus area FA2 by receiving information related to the size of the second focus area FA2 from the user, so that the second focus area FA2 only partially includes the area where the processing area G is located.

[0098] However, it is not limited thereto, and a detailed description of a method of the control portion 300 setting the first focus area FA1 and the second focus area FA2 will be described in detail in the description of the depth measurement method of the scribing workpiece processing area.

[0099] Reference Figure 2 , FIG. 3A to FIG. 4C According to an embodiment of the present invention, the control unit 300 can detect an area of ​​the surface image of the object OB, specifically, can detect the position of the preset lens unit 110 focused on the focusing area (the first focusing area FA1, the second focusing area FA2).

[0100] The control part 300 according to one embodiment of the present invention is electrically connected to the driving part 200 and the imaging part 100 , respectively, and may perform a contrast auto focus (contrast AF) action on a surface area of ​​the object OB forming the processing area G.

[0101] A method for performing an autofocus (contrast AF) action is described below, wherein the control unit 300 obtains a surface image of a focus area (a first focus area FA1, a second focus area FA2) from the imaging unit 100 while controlling the driving of the driving unit 200, thereby performing a contrast autofocus (contrast AF) action on the surface area of ​​the object body OB forming the processing area G.

[0102] The control section 300 may change the position of the lens section 110 by controlling the driving section 200. The lens section 110 may receive light from an area of ​​the surface of the object body OB included in the focusing area (the first focusing area FA1, the second focusing area FA2) and transfer it to the image sensor section 120, and the image sensor section 120 acquires the surface image of the object body OB included in the focusing area (the first focusing area FA1, the second focusing area FA2) therethrough.

[0103] The control section 300 may receive the surface image acquired by the image sensor section 120 and measure the contrast of the surface image of the object body OB included in the focus area (the first focus area FA1, the second focus area FA2). Specifically, the control section 300 may measure the brightness information of each area of ​​the surface image of the object body OB included in the focus area (the first focus area FA1, the second focus area FA2), and measure the contrast of the surface image of the object body OB included in the focus area (the first focus area FA1, the second focus area FA2) using the brightness information difference of each area.

[0104] As an example, the control section 300 may measure the contrast using a difference between the lux value of the brightest portion and the lux value of the darkest portion of the surface image of the object OB included in the focus areas (first focus area FA1, second focus area FA2).

[0105] As the position of the lens section 110 changes, brightness information of each area of ​​the surface image of the object OB included in the focus areas (first focus area FA1, second focus area FA2) changes, and the control section 300 can measure the contrast of the focus areas (first focus area FA1, second focus area FA2) changed according to the position of the lens section 110.

[0106] Reference FIG. 3A to FIG. 4C According to an embodiment of the present invention, the control unit 300 can drive the driving unit 200 to move the lens unit 110 along the moving axis, and while the control unit 300 moves the lens unit 110, it can use the focus area (first focus area FA1, second focus area FA2) image acquired from the image sensor unit 120 to extract the contrast of the focus area (first focus area FA1, second focus area FA2).

[0107] Thus, the control unit 300 can obtain the position of the lens unit 110 and the contrast relationship of the surface image included in the focus area (the first focus area FA1, the second focus area FA2), and through this, a contrast auto focus (contrast AF) action can be performed by deriving the position of the lens unit 110 with the largest contrast.

[0108] Reference Figure 2 and Figure 5 The control unit 300 can measure the depth of the processing area G formed on the surface of the object OB by performing contrast autofocus on different focus areas (first focus area FA1, second focus area FA2). The relevant description will be described in the method for measuring the depth of the processing area of ​​the scribing workpiece.

[0109] Reference Figure 1, the illumination part 400 according to one embodiment of the present invention is used to irradiate light to the surface of the object body OB forming the processing area G, and includes a light source part 410 and a mirror part 420.

[0110] The light source unit 410 may be formed of various devices that can be used as a light source, such as an LED and an incandescent lamp.

[0111] The mirror unit 420 may guide the light L generated from the light source unit 410 to move in accordance with the optical axis of the lens unit 110. Specifically, a plurality of mirror units 420 may be provided, and the plurality of mirror units 420 may be arranged at a preset angle so that the light L generated from the light source unit 410 can be irradiated to the surface of the object OB along the optical axis of the lens unit 110.

[0112] Thus, the light L generated from the light source unit 410 is irradiated onto the surface of the object OB along an optical axis perpendicular to the surface of the object OB, so that there is no shadow in the area forming the processing area G, thereby having an effect that the control unit 300 can measure the brightness information of each area of ​​the surface image of the object OB included in the focus area (first focus area FA1, second focus area FA2).

[0113] The following will describe a method and effect of measuring the depth of a machining area of ​​a scribed workpiece according to an embodiment of the present invention.

[0114] Figure 6 1 is a sequence diagram of a method for measuring the depth of a machining area of ​​a scribed workpiece according to an embodiment of the present invention. Figure 7 is a sequence diagram of a method for detecting a first position of a lens portion according to an embodiment of the present invention. Figure 8 FIG. 1 is a sequence diagram of a method for detecting a second position of a lens portion according to an embodiment of the present invention.

[0115] Reference Figure 6 In one embodiment of the present invention, a method for measuring the depth of a processing area of ​​a scribed workpiece (hereinafter referred to as "the method for measuring the depth of a processing area") may include the following steps: step S100, acquiring a surface image of an object body having a processing area G formed therein from an imaging portion provided with a lens portion; step S200, detecting a first position of the lens portion, which is focused on a first area separated from the processing area G on the surface image; step S300, detecting a second position of the lens portion, which is focused on a second area having the processing area G formed therein on the surface image; and step S400, measuring the depth of the processing area G using the first position and the second position of the lens portion; the first position P1 and the second position P2 of the lens portion 110 are determined by the contrast measured when the lens portion 110 moves.

[0116] In the step of acquiring the surface image of the object body having the processing area G formed therein (step S100 ) according to one embodiment of the present invention, the control unit 300 may divide the surface image of the object body OB into a plurality of preset areas, and may acquire brightness information of each divided area.

[0117] The preset area is set as a unit pixel, and the brightness information of each divided area can be the brightness value of each pixel. However, it is not limited thereto, the preset area can be set as a set of multiple unit pixels, and the brightness information of each divided area can be at least one of the average value, median value, maximum value or minimum value of the brightness values ​​of the unit pixels forming the set.

[0118] Hereinafter, in this specification, the “first area A1” may be interpreted as an area where the processing area G is not formed on the surface of the object body OB, and the “second area A2” may be interpreted as an area where the processing area G is formed on the surface of the object body OB.

[0119] Reference Figures 2 to 3C , Figure 7 According to an embodiment of the present invention, the step of detecting a first position of a lens portion focused on a first area (step S200) may include the following steps: step S210, setting an area of ​​a surface image including both the first area and the second area as a first focusing area; step S220, performing a contrast autofocus action on the first focusing area; and step S230, detecting the position of the lens portion when the contrast of the first focusing area is maximum as the first position.

[0120] Reference Figure 2 In the step of setting an area of ​​the surface image including both the first area and the second area as the first focus area (step S210), the control unit 300 sets an area of ​​the surface image (including both the area where the processed area G is located and the area where the non-processed area G is located on the surface image of the object body OB obtained from the imaging unit 100) as the first focus area FA1.

[0121] As an embodiment, the control part 300 may receive a control command from the outside and set the position and size of the first focus area FA1.

[0122] Specifically, the user may set a preset point on the surface image of the object body OB acquired from the imaging section 100 as the center C1 of the first focus area, and may set the shape and area of ​​the first focus area FA1.

[0123] As an embodiment, the control unit 300 may set the position and size of the first focus area FA1 according to a preset algorithm.

[0124] The control part 300 may set the first focusing area FA1 according to a preset algorithm in such a manner that the center C1 of the first focusing area coincides with the center CL of the processing area.

[0125] The control unit 300 can set the width direction of the processing area G according to a preset algorithm (based on Figure 2 The length W1 of the first focusing area FA1 in the up and down directions).

[0126] As an embodiment, the length W1 of the first focusing area FA1 in the width direction of the processing area G is preferably greater than 1.1 times and less than 10 times the length W0 in the width direction of the processing area G, more preferably greater than 1.3 times and less than 3 times, and further preferably greater than 1.5 times and less than 2 times.

[0127] The control part 300 may set the first focus area FA1 in such a manner that an area of ​​the first area A1 included in the first focus area FA1 is relatively larger than an area of ​​the second area A2 included in the first focus area FA1.

[0128] As an embodiment, the area of ​​the first region A1 included in the first focus area FA1 is preferably greater than 1.1 times and less than 10 times the area of ​​the second region A2 included in the first focus area FA1, more preferably greater than 1.3 times and less than 3 times, and further preferably greater than 1.5 times and less than 2 times.

[0129] Reference FIG. 3A to FIG. 3C In the step of performing a contrast auto focusing action on the first focus area (step S220) according to an embodiment of the present invention, the control unit 300 drives the driving unit 200 so that the lens unit 110 moves along a preset moving axis, and the control unit 300 can measure the contrast of the first focus area FA1 obtained when the lens unit 110 moves.

[0130] Specifically, the control part 300 may acquire images of the first focus area FA1 having different contrasts from the image sensor part 120 as the lens part 110 moves, and through this, the control part 300 may extract brightness information of the first focus area FA1 according to the position of the lens part 110 .

[0131] Reference Figure 3B In the step of detecting the position of the lens unit when the contrast of the first focusing area is maximum as the first position (step S230) according to an embodiment of the present invention, the control unit 300 can use the extracted brightness information of the first focusing area FA1 of the lens unit 110 to detect the position of the lens unit 110 when the contrast of the first focusing area FA1 is maximum as the first position P1.

[0132] As an alternative embodiment, the control portion 300 may detect the position of the lens portion 110 at which the contrast of the first focus area FA1 is changed as the lens portion 110 moves, as the first position P1.

[0133] As an embodiment, after the first position P1 of the lens portion 110 is set as a reference point, a step of detecting a second position of the lens portion focused on the second area (step S300 ) may be performed.

[0134] Reference Figures 2 to 4C , Figure 8 According to an embodiment of the present invention, the step of detecting the second position of the lens portion focused on the second area (step S300) may include the following steps: step S310, acquiring the position information of the processing area G; step S320, setting an area of ​​the surface image as the second focusing area based on the acquired position information of the processing area G; step S330, performing a contrast autofocus action on the second focusing area; step S340, detecting the position of the lens portion when the contrast of the second focusing area is maximum as the second position; wherein the second focusing area may be included in the second area.

[0135] In the step of acquiring position information of the processing region G (step S310 ) according to an embodiment of the present invention, the control unit 300 may acquire information on a region where the processing region G is located on the surface image of the object OB acquired from the imaging unit 100 .

[0136] Reference Figure 2 According to an embodiment of the present invention, in the step of setting an area of ​​the surface image as the second focus area based on the acquired position information of the processing area G (step S320), the control unit 300 can set an area of ​​the surface image (including the area where the processing area G is located on the surface image of the object body OB acquired from the imaging unit 100) as the second focus area FA2.

[0137] As an embodiment, the control unit 300 may receive a control command from the outside and set the position and size of the second focus area FA2.

[0138] Specifically, the user may set a preset point on the surface image of the object body OB acquired from the imaging section 100 as the center C2 of the second focus area, and may set the shape and area of ​​the second focus area FA2.

[0139] As an embodiment, the control unit 300 may set the position and size of the second focus area FA2 according to a preset algorithm.

[0140] The control part 300 may set the second focusing area FA2 in a manner that the center C2 of the second focusing area coincides with the center CL of the processing area G according to a preset algorithm.

[0141] Reference Figure 2 , the control part 300 may set the second focusing area FA2 in such a manner that the center C2 of the second focusing area coincides with the center C1 of the first focusing area.

[0142] The control unit 300 can set the width direction of the processing area G according to a preset algorithm (based on Figure 2 The length W2 of the second focusing area FA2 in the up and down directions).

[0143] As an embodiment, the length W2 of the second focus area FA2 in the width direction of the processing area G is preferably greater than 0.3 times and less than 1 times the length W0 in the width direction of the processing area G, and more preferably greater than 0.5 times and less than 1 times.

[0144] As an optional embodiment, the control unit 300 uses the length W1 of the first focus area FA1 in the width direction of the processing area G to set the length W2 of the second focus area FA2 in the width direction of the processing area G. Specifically, the length W1 of the first focus area FA1 in the width direction of the processing area G may be greater than 1.2 times and less than 10 times the length W2 of the second focus area FA2 in the width direction of the processing area G, preferably greater than 1.5 times and less than 3 times, and more preferably greater than 2 times and less than 3 times.

[0145] Reference FIG. 4A to FIG. 4C According to an embodiment of the present invention, in the step of performing a contrast auto focusing action on the second focus area (step S330), the control unit 300 drives the driving unit 200 so that the lens unit 110 moves along a preset moving axis, and the control unit 300 can measure the contrast of the second focus area FA2 obtained when the lens unit 110 moves.

[0146] Specifically, as the lens portion 110 moves, the control portion 300 may acquire an image of the second focus area FA2 having different contrasts from the image sensor portion 120 , and through this, the control portion 300 may extract brightness information of the second focus area FA2 according to the position of the lens portion 110 .

[0147] Reference Figure 4BAccording to an embodiment of the present invention, in the step of detecting the position of the lens unit when the contrast of the second focus area is maximum as the second position (step S340), the control unit 300 can use the extracted brightness information of the second focus area FA2 according to the position of the lens unit 110 to detect the position of the lens unit 110 when the contrast of the second focus area FA2 is maximum as the second position P2.

[0148] As an alternative embodiment, the control portion 300 may detect, as the second position P2, a position of the lens portion 110 at which the contrast of the second focus area FA2 is changed as the lens portion 110 moves.

[0149] Reference Figure 5 In the step of measuring the depth of the processing area G using the first position and the second position of the lens part (step S400), the control part 300 can measure the depth of the processing area G using the difference D between the first position P1 and the second position P2 of the lens part 110.

[0150] Specifically, the control part 300 may measure the depth of the processing region G formed on the surface of the object OB using the distance D between the first position P1 and the second position P2 in the direction perpendicular to the surface of the object OB.

[0151] Thus, there is an effect that there is no need to cut the object body OB and confirm the cross section of the processing area G with a separate microscope, but the depth of the processing area G can be accurately measured by setting the focusing areas (first focusing area FA1, second focusing area FA2) differently and measuring the contrast of the surface image.

[0152] The idea of ​​the present invention should not be limited to the above-described embodiments, and in addition to the scope of the patent claims, all scopes equivalent to or equivalently changed to the scope of these claims fall within the scope of the idea of ​​the present invention.

Claims

1. A method for measuring the depth of a machining area of ​​a scribing workpiece, in, include: a surface image acquisition step of acquiring a surface image of the object whose surface is processed from an imaging unit provided with a lens unit; a first position detection step of detecting a first position of the lens portion focused on a first area separated from a processing area on the surface image; a second position detection step of detecting a second position of the lens portion in a second area where the processing area focused on the surface image is located; and a depth measuring step of measuring the depth of the processing area using the first position and the second position of the lens portion, The first position and the second position of the lens portion are determined by contrast measured when the lens portion moves.

2. The method for measuring the depth of a processing area of ​​a scribed workpiece according to claim 1, wherein: The step of detecting the first position of the lens portion further comprises the following steps: An area of ​​the surface image including both the first area and the second area is set as a first focus area.

3. The method for measuring the depth of a processing area of ​​a scribed workpiece according to claim 2, wherein: The step of detecting the first position of the lens portion further comprises the following steps: By performing a contrast auto focus operation on the first focus area, the position of the lens unit when the contrast of the first focus area is maximized is detected as the first position.

4. The method for measuring the depth of a processing area of ​​a scribed workpiece according to claim 3, wherein: The center of the first focusing area coincides with the center of the processing area.

5. The method for measuring the depth of a processing area of ​​a scribed workpiece according to claim 2, wherein: The step of detecting the second position of the lens portion comprises the following steps: Acquiring location information of the processing area; and Based on the acquired position information of the processing area, an area of ​​the surface image is set as a second focus area, The second focusing area is included in the second area.

6. The method for measuring the depth of a processing area of ​​a scribed workpiece according to claim 5, wherein: In the step of detecting the second position of the lens portion: By performing a contrast autofocus operation on the second focus area, the position of the lens unit when the contrast of the second focus area is maximized is detected as the second position.

7. The method for measuring the depth of a processing area of ​​a scribed workpiece according to claim 5, wherein: The center of the first focusing area coincides with the center of the second focusing area.

8. The method for measuring the depth of a processing area of ​​a scribed workpiece according to claim 1, wherein: The angle between the normal vector of the surface of the object passing through the center of the processing area and the optical axis of the lens portion is less than 5°.

9. The method for measuring the depth of a processing area of ​​a scribed workpiece according to claim 1, wherein: The lens portion is movable along a preset movement axis, and the movement axis is perpendicular to a surface of the object.

10. The method for measuring the depth of a processing area of ​​a scribed workpiece according to claim 6, wherein: In the step of measuring the depth of the processing area: The depth of the processing area is calculated using a difference between the first position and the second position of the lens portion.

11. A device for measuring the depth of a processing area of ​​a scribing workpiece, in, include: An imaging unit, used for acquiring a surface image of an object whose surface is processed; a lens portion located between the imaging portion and the object, and the lens portion is movable in a direction perpendicular to a surface of the object; and a control unit, used to control the lens unit, The control unit is configured as follows: The contrast of the surface image acquired when the lens portion moves in the one direction can be measured.

12. The device for measuring the depth of a scribing workpiece processing area according to claim 11, wherein: The control unit is configured as follows: capable of detecting a position of the lens portion focused on a first area and a position of the lens portion focused on a second area, wherein the first area is an area separated from a processing area where processing is performed on the surface of the object, and the second area is an area where the processing area is located; The depth of the processed area is measured by using the position of the lens portion focused on the first area and the position of the lens portion focused on the second area where the processed area is located.

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