Apparatus, method, and recording medium for imaging of printed circuit board

Abstract

The present disclosure proposes an apparatus for controlling the position of at least one of one or more light sources or image sensors for imaging of a printed circuit board. The apparatus according to the present disclosure may comprise: a conveyor belt on which a target printed circuit board is disposed and which moves the target printed circuit board to a first substrate position; a light source which irradiates one or more beams of first pattern light to an edge line of the target printed circuit board positioned at the first substrate position; an image sensor which captures one or more beams of first reflected light to generate one or more first images; and one or more processors. The one or more processors may calculate, on the basis of the one or more first images, an edge offset value indicating an alignment deviation between a second substrate position, which is a predetermined position for substrate inspection, and the target printed circuit board positioned at the first substrate position, and control, according to the calculated edge offset value, the position of at least one of the one or more light sources or image sensors during inspection of the target printed circuit board.

Description

Device, method, and recording medium for imaging a printed circuit board

[0001] The present disclosure relates to a technology for imaging a printed circuit board.

[0002] Before mounting components on a printed circuit board, a solder printing device (e.g., a screen printer) can apply solder onto the pads of the board. Afterward, a solder paste inspection (SPI) device can photograph and inspect the condition of the applied solder.

[0003] In addition, components can be mounted on the pads of a printed circuit board coated with solder using Surface Mount Technology (SMT), and the mounted components can be imaged and inspected.

[0004] In the process of forming a printed circuit board and an object to be inspected within the printed circuit board (e.g., solder, components, dies, etc.), various inspections may be performed to determine whether the process has been properly carried out.

[0005] When performing such inspections, tasks such as verifying whether the printed circuit board is properly placed within the equipment may be carried out.

[0006] The present disclosure provides a technology for imaging a printed circuit board.

[0007] The present disclosure proposes an apparatus for controlling the positions of one or more light sources and image sensors for imaging a printed circuit board. The apparatus according to the present disclosure comprises: a conveyor belt on which a target printed circuit board is placed and which moves the target printed circuit board to a first board position; one or more light sources that irradiate one or more first patterned light onto an edge line of the target printed circuit board located at the first board position; an image sensor that captures one or more first reflected light generated by the one or more first patterned light being reflected from the edge line to generate one or more first images; one or more processors; and one or more memories in which instructions to be executed by the one or more processors are stored. When the instructions are executed, the one or more processors calculate an edge offset value representing an alignment deviation between a second board position, which is a predetermined position for board inspection, and the target printed circuit board located at the first board position, based on the one or more first images, and can control the position of at least one of the one or more light sources or the image sensor during inspection of the target printed circuit board based on the calculated edge offset value.

[0008] In one embodiment, the one or more processors can identify the second substrate location and the edge line for each of the one or more first images, and calculate the edge offset value based on the difference between the first axis coordinate of the second substrate location and the first axis coordinate corresponding to the edge line within each of the first images.

[0009] In one embodiment, the first axis may represent an axis parallel to the direction of movement of the conveyor belt.

[0010] In one embodiment, the second axis coordinate range corresponding to the edge line may be included within the second axis coordinate range of the straight edge line existing on the target printed circuit board.

[0011] In one embodiment, the one or more processors can move the one or more light sources and the image sensor in a plane parallel to the movement plane of the conveyor belt so that the edge line of the target printed circuit board is included in the imaging observation area of ​​the image sensor.

[0012] In one embodiment, the target printed circuit board includes one or more inspection areas located at the upper edge of the target printed circuit board, and the one or more processors move the one or more light sources and the image sensors from a first position corresponding to each inspection area to a second position reflecting the edge offset value, and can obtain one or more second images by capturing each inspection area at the second position.

[0013] In one embodiment, the one or more processors may obtain one second image by capturing a first inspection area located in a first corner area of ​​the target printed circuit board, and obtain another second image by capturing a second inspection area located in a second corner area symmetrical to the first corner area with respect to the center of the target printed circuit board.

[0014] In one embodiment, the one or more processors can calculate a fiducial offset through one or more second images obtained by capturing the one or more inspection areas, and control the position of at least one of the one or more light sources or the image sensors during inspection of the target printed circuit board based on an adjustment value obtained by summing the fiducial offset and the edge offset value.

[0015] In one embodiment, the one or more processors can gradually accelerate the conveyor belt to a first speed upon receiving a signal detecting the target printed circuit board from a first sensing sensor, and gradually decelerate the conveyor belt to a second speed lower than the first speed and stop it upon receiving a signal detecting the target printed circuit board from a second sensing sensor.

[0016] In one embodiment, the one or more processors may move the conveyor belt by a preset first distance at the first speed when the signal detecting the target printed circuit board received from the first detection sensor is interrupted, and after the conveyor belt has moved by the first distance, move the conveyor belt by decelerating it from the first speed to the second speed.

[0017] In one embodiment, the one or more processors can calculate the first distance by subtracting the length of the target printed circuit board, the travel distance required to decelerate from the first speed to the second speed, and the minimum distance required to travel at the second speed from the distance from the first sensing sensor to the second sensing sensor.

[0018] In one embodiment, the one or more processors may, upon receiving a signal detecting the target printed circuit board from the second sensing sensor, move the conveyor belt by a preset second distance at the second speed and then gradually reduce the speed to stop it.

[0019] In one embodiment, the one or more processors may, when receiving a signal detecting another printed circuit board from the second sensing sensor before the target printed circuit board is placed, move the conveyor belt in the reverse direction at a third speed and then accelerate the conveyor belt in the forward direction to a fourth speed, and when receiving a signal detecting the other printed circuit board from the second sensing sensor again, decelerate the conveyor belt from the fourth speed and stop it.

[0020] In one embodiment, the fourth speed may be set to a size smaller than the second speed.

[0021] The present disclosure proposes a method for controlling the positions of one or more light sources and image sensors for imaging a printed circuit board. A method for inspecting a printed circuit board according to one embodiment of the present disclosure may include: a step of positioning a target printed circuit board and moving the target printed circuit board to a first board position; a step of irradiating one or more first pattern lights onto an edge region of the target printed circuit board located at the first board position; a step of capturing one or more first reflected lights generated by the one or more first pattern lights being reflected from the edge region to generate one or more first images; a step of calculating an edge offset value representing an alignment deviation between a second board position, which is a predetermined position for board inspection, and the target printed circuit board located at the first board position, based on the one or more first images; and a step of controlling the position of at least one of the one or more light sources or the image sensor during inspection of the target printed circuit board based on the calculated edge offset value.

[0022] The present disclosure proposes a non-transient computer-readable recording medium that records instructions for controlling the position of an image sensor for imaging a printed circuit board. Instructions recorded on the recording medium according to one embodiment of the present disclosure may be instructions to be executed by one or more processors or to be performed on a computer. The instructions may cause the one or more processors to position a target printed circuit board, move the target printed circuit board to a first board position, irradiate one or more first pattern lights onto an edge region of the target printed circuit board located at the first board position, capture one or more first reflected lights generated by the one or more first pattern lights reflecting from the edge region to generate one or more first images, calculate an edge offset value representing an alignment deviation between a second board position, which is a predetermined position for board inspection, and the target printed circuit board located at the first board position based on the one or more first images, and control the position of at least one of the one or more light sources or the image sensor during inspection of the target printed circuit board based on the calculated edge offset value.

[0023] According to at least one embodiment of the present disclosure, an edge offset value for an alignment position of a printed circuit board can be calculated.

[0024] According to at least one embodiment of the present disclosure, the position of at least one of one or more light sources or image sensors can be controlled based on an edge offset value determined for a printed circuit board.

[0025] According to at least one embodiment of the present disclosure, as the printed circuit board reaches a first substrate position, the position of the image sensor can be adjusted so that the image sensor has an observation area including an edge region of the target printed circuit board and a second substrate position.

[0026] According to at least one embodiment of the present disclosure, the speed of the conveyor belt can be controlled to move the printed circuit board to a first board position.

[0027] The effects according to the technical concept of the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by a person skilled in the art from the description in the specification.

[0028] FIG. 1 is a schematic diagram showing an apparatus according to one embodiment of the present disclosure.

[0029] FIG. 2 is a block diagram of a device according to one embodiment of the present disclosure.

[0030] FIG. 3 is a diagram illustrating the process of a device according to one embodiment of the present disclosure moving a target printed circuit board from left to right and placing it at a first board position.

[0031] FIG. 4 is a drawing illustrating a target printed circuit board according to one embodiment of the present disclosure.

[0032] FIG. 5 is a diagram illustrating the process of a device according to one embodiment of the present disclosure moving a target printed circuit board from right to left and placing it at a first board position.

[0033] FIG. 6 is a diagram illustrating the process of a device according to one embodiment of the present disclosure capturing one or more inspection areas included in a target printed circuit board and calculating a fiducial offset.

[0034] FIG. 7 is a diagram illustrating the process of a device according to one embodiment of the present disclosure controlling the position of an imaging device.

[0035] FIG. 8 is a diagram illustrating the process of a device according to one embodiment of the present disclosure moving a target printed circuit board to a first board position.

[0036] FIG. 9 illustrates a graph showing the speed of a conveyor belt over time according to one embodiment of the present disclosure.

[0037] FIG. 10 is a drawing that explains in more detail the process of a device according to one embodiment of the present disclosure decelerating the speed of a target printed circuit board.

[0038] FIG. 11 is a diagram illustrating the process of a device according to one embodiment of the present disclosure performing a pre-run operation.

[0039] FIG. 12 illustrates a graph showing the speed over time of a conveyor belt for inspecting another printed circuit board according to one embodiment of the present disclosure.

[0040] FIGS. 13 and FIGS. 14 are flowcharts schematically illustrating the operation performed by a device according to one embodiment of the present disclosure.

[0041] The various embodiments described in this disclosure are illustrative for the purpose of clearly explaining the technical concept of this disclosure and are not intended to limit it to specific embodiments. The technical concept of this disclosure includes various modifications, equivalents, alternatives, and embodiments selectively combined from all or part of each embodiment described in this disclosure. Furthermore, the scope of the technical concept of this disclosure is not limited to the various embodiments presented below or the specific descriptions thereof.

[0042] Terms used in this disclosure, including technical or scientific terms, may have the meaning generally understood by those skilled in the art to which this disclosure pertains, unless otherwise defined.

[0043] Expressions used in this disclosure, such as “comprising,” “may compose,” “possessing,” “possessing,” “having,” and “possessing,” mean that the subject feature (e.g., function, operation, or component, etc.) exists and do not exclude the existence of other additional features. That is, such expressions should be understood as open-ended terms implying the possibility of including other embodiments.

[0044] Singular expressions used in this disclosure may include the meaning of the plural form unless otherwise indicated by the context, and this applies likewise to singular expressions described in the claims.

[0045] Expressions such as "first," "second," or "first," "second," etc., used in this disclosure are used to distinguish one object from another when referring to a plurality of objects of the same kind, unless otherwise indicated by the context, and do not limit the order or importance of said objects.

[0046] Expressions used in the present disclosure, such as “A, B, and C,” “A, B, or C,” “A, B, and / or C,” or “at least one of A, B, and C,” “at least one of A, B, or C,” “at least one of A, B, and / or C,” “at least one selected from A, B, and C,” “at least one selected from A, B, or C,” or “at least one selected from A, B, and / or C,” may mean each of the listed items or all possible combinations of the listed items. For example, “at least one selected from A and B” may refer to (1) A, (2) at least one of A, (3) B, (4) at least one of B, (5) at least one of A and at least one of B, (6) at least one of A and B, (7) at least one of B and A, and (8) all of A and B.

[0047] The term “part” as used in this disclosure may be a collective concept encompassing software, or hardware components such as FPGAs (field-programmable gate arrays), ASICs (application-specific integrated circuits), and optical elements. However, “part” is not limited to hardware and software. “Part” may be configured to be stored in an addressable storage medium or configured to execute one or more processors. In one embodiment, “part” may include components such as software components, object-oriented software components, class components, and task components, as well as processors, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables.

[0048] The expression “based on” as used in this disclosure is used to describe one or more factors affecting an act or action of a decision or judgment described in the phrase or sentence containing such expression, and this expression does not exclude additional factors affecting said act or action of a decision or judgment.

[0049] As used in the present disclosure, the expression that a certain component (e.g., a first component) is "connected" or "connected" to another component (e.g., a second component) may mean that the said certain component is not only directly connected or connected to the said other component, but is also connected or connected through a new other component (e.g., a third component).

[0050] As used in this disclosure, the expression "configured to" may have meanings such as "set to," "capable of," "modified to," "made to," or "capable of." Such expression is not limited to the meaning of "specifically designed in hardware," and, for example, a processor configured to perform a specific operation may mean a generic-purpose processor capable of performing that specific operation by executing software.

[0051] To describe various embodiments of the present disclosure, an orthogonal coordinate system having mutually orthogonal X-axis, Y-axis, and Z-axis may be defined. Expressions such as "X-axis direction," "Y-axis direction," and "Z-axis direction" used in the present disclosure may refer to the two directions in which each axis of the orthogonal coordinate system extends, unless specifically defined otherwise in the description. Additionally, a + sign preceding each axis direction may indicate a positive direction, which is one of the two directions extending in that axis direction, and a - sign preceding each axis direction may indicate a negative direction, which is the other of the two directions extending in that axis direction.

[0052] Directional indicators used in this disclosure, such as "upward" and "upward," are based on the positive Z-axis direction in the attached drawings unless specifically defined otherwise in the description, and directional indicators, such as "downward" and "downward," mean the opposite direction.

[0053] In the present disclosure, a substrate is a plate or container for mounting devices such as semiconductor chips or dies, and can serve as a pathway for electrical signals between devices. The substrate may be used for the fabrication of integrated circuits, etc., and may be made of a material such as silicon. For example, the substrate may be a printed circuit board (PCB), and may be referred to as a wafer, etc., depending on the embodiment.

[0054] Various embodiments of the present disclosure will be described below with reference to the accompanying drawings. In the accompanying drawings and the description thereof, identical or substantially equivalent components may be given the same reference numerals. Furthermore, in the description of the various embodiments below, the description of identical or corresponding components may be omitted, but this does not mean that such components are not included in the embodiments.

[0055] FIG. 1 is a schematic diagram showing an apparatus (100) according to one embodiment of the present disclosure. A technique for controlling the position of an image sensor for capturing an image of a printed circuit board (PCB) according to one embodiment can be implemented through an apparatus (e.g., apparatus (100)) according to various embodiments.

[0056] In one embodiment, the device (100) may include one or more light sources (110), an image sensor (120), and / or a conveyor belt (140). One or more light sources (110) and an image sensor (120) may be implemented as a single integrated imaging device (130). The device (100) may further include one or more processors capable of controlling one or more light sources (110), an image sensor (120), and a conveyor belt (140). In this case, one or more processors may be electrically connected to one or more light sources (110), an image sensor (120), and a conveyor belt (140). In this specification, one or more processors may be referred to as processors. That is, the expression processor may mean a set of one or more processors unless the context clearly indicates otherwise.

[0057] In one embodiment, the conveyor belt (140) may represent a conveyor system, and a printed circuit board may be placed on the conveyor belt (140). The conveyor belt (140) may include a conveyor rail (150). Additionally, the conveyor belt (140) may further include a plurality of sensing sensors (191, 192, 193). For example, the first sensing sensor is an entry sensor and can detect whether a printed circuit board is placed within the conveyor belt (140). The second sensing sensor (192) may be used to determine when a printed circuit board placed within the conveyor belt (140) requires deceleration during movement. The third sensing sensor (193) is an exit sensor and can detect whether a printed circuit board has been removed from the conveyor belt (140). However, the conveyor belt (140) may include additional sensing sensors in addition to the plurality of sensing sensors (191, 192, 193) described above, and some of the plurality of sensing sensors (191, 192, 193) may be omitted.

[0058] In the following description, for clarity of explanation, the conveyor belt (140), the conveyor rail (150), and the plurality of sensing sensors (191, 192, 193) are described as separate devices distinct from one another. In this case, "conveyor belt (140)" is used to mean the belt itself. The conveyor rail (150) can support the conveyor belt (140). The conveyor rail (150) can be designed as a fixed structure or can be separated into multiple parts and arranged to support the conveyor belt (140). Additionally, a single printed circuit board may be placed on the conveyor belt (140), but is not limited thereto, and there may also be cases where multiple printed circuit boards are placed simultaneously on the conveyor belt (140). The processor (160) can operate the conveyor belt (140) to move the printed circuit board located on the conveyor belt (140). Each of the plurality of sensing sensors (191, 192, 193) can detect a printed circuit board located on the conveyor belt (140) and generate a sensing signal. The sensing signals generated from the plurality of sensing sensors (191, 192, 193) can be utilized as a feedback mechanism to control the movement speed and direction of movement of the conveyor belt (140). Below, the case in which a target printed circuit board is placed on the conveyor belt (140) will be mainly described.

[0059] In one embodiment, one or more light sources (110) may irradiate pattern light toward at least a portion of a target printed circuit board to perform an inspection using pattern light. For example, one or more light sources (110) may irradiate pattern light toward at least a portion of a target printed circuit board as the target printed circuit board moves to a first board position by a conveyor belt (140). An image sensor (120) may capture reflected light generated by the pattern light irradiated by one or more light sources (110) being reflected from at least a portion of the target printed circuit board, and may generate an image of the target printed circuit board using the captured reflected light. The image sensor (120) may transmit the generated image to a processor.

[0060] In one embodiment, the processor may receive an image of a target printed circuit board from an image sensor (120). Based on the received image, the processor may calculate an edge offset value representing an alignment deviation between a target printed circuit board located at a first substrate location and a second substrate location, which are predetermined locations for board inspection and for capturing the target printed circuit board. Based on the calculated edge offset value, the processor may control the location of at least one of one or more light sources (110) or image sensors (120) during the inspection of the target printed circuit board.

[0061] In one embodiment, an imaging device (130) comprising one or more light sources (110) and an image sensor (120) may have its position controlled by a processor. For example, the processor may move the imaging device (130) in a horizontal direction on a first plane parallel to the plane on which the target printed circuit board is placed. Additionally, the processor may move the imaging device (130) in a vertical direction on a second plane perpendicularly intersecting the first plane. Through horizontal or vertical control of the imaging device (130), the position of at least one of the one or more light sources (110) or the image sensor (120) may be controlled. However, the method of controlling the position of the one or more light sources (110) or the image sensor (120) is not limited thereto, and the position of only the one or more light sources (110) or the image sensor (120) may be controlled by separating them from other components of the imaging device (130) without moving the imaging device (130).

[0062] Additionally, the device (100) can perform imaging of a target printed circuit board using an imaging device (130) as the position of one or more light sources (110) or image sensors (120) is controlled based on the edge offset value of the target printed circuit board. At this time, since the imaging position of one or more light sources (110) and image sensors (120) is precisely controlled by a processor based on the edge offset value, one or more lenses included in the image sensor (120) can accurately image each area of ​​the target printed circuit board to be photographed. Through this, the imaging device (130) can generate an image of the target printed circuit board more accurately and precisely. Furthermore, the device (100) can perform high-precision inspection through the precise image of the target printed circuit board. Here, the inspection of the target printed circuit board may include performing tasks such as verifying whether components are properly placed on the target printed circuit board. Here, 'device' may refer to a component or chipset used as a constituent in electronic devices in general, such as electrical circuits and semiconductor devices. For example, a device may include coils, capacitors, resistors, transistors, diodes, LEDs, etc.

[0063] FIG. 2 is a block diagram of a device (100) according to one embodiment of the present disclosure. In one embodiment, the device (100) may include one or more light sources (110), image sensors (120), conveyor belts (140), processors (160), memory (170), and / or communication circuits (180). In one embodiment, at least one of these components of the device (100) may be omitted, or other components may be added to the device (100). In one embodiment, additionally or alternatively, some components may be implemented as a single or multiple entities. The term "memory" may mean a set of one or more memories unless the context clearly indicates otherwise. In one embodiment, at least some of the components inside and outside the device (100) may be connected to each other via a bus, GPIO (general purpose input / output), SPI (serial peripheral interface) or MIPI (mobile industry processor interface), etc., to exchange data and / or signals.

[0064] In one embodiment, a target printed circuit board may be placed on a conveyor belt (140). The conveyor belt (140) may move in a first axial direction or a second axial direction by a control signal received from a processor (160). The first axis may represent the main direction of movement of the conveyor belt (140), and the second axis may represent an axis orthogonal to the first axis within a plane parallel to the upper surface of the conveyor rail (150) (or conveyor belt (140)) (i.e., the plane on which the target printed circuit board is placed). As the conveyor belt (140) moves, the target printed circuit board may also move along with it. In this way, the conveyor belt (140) may move the target printed circuit board to a first board position.

[0065] In one embodiment, each of the one or more light sources (110) can irradiate one or more patterned lights onto a target printed circuit board. For example, as the target printed circuit board reaches a first substrate position, the one or more light sources (110) can irradiate one or more first patterned lights onto an edge region of the target printed circuit board. At this time, the one or more light sources (110) can generate patterned lights in various ways. The pattern of the patterned light can be formed by a digital method or by an analog method. Digital methods may include a liquid crystal transmission method using an LCD (Liquid Crystal Display), a liquid crystal reflection method using LCoS (Liquid Crystal on Silicon), and a mirror reflection method using a DMD (Digital Micromirror Device) or DLP (Digital Light Processing). Analog methods may include a method of forming a pattern using patterns such as periodic patterns, gradient patterns, and grid patterns.

[0066] In one embodiment, the image sensor (120) can capture one or more reflected light. For example, the image sensor (120) can capture one or more first reflected light generated by one or more first pattern light being reflected from an edge region of a target printed circuit board. The image sensor (120) can generate one or more first images including an edge region of a target printed circuit board based on the one or more captured first reflected light. The image sensor (120) can transmit the generated one or more first images to a processor (160). The image sensor (120) may be implemented as a Charge Coupled Device (CCD) or a Complimentary Metal Oxide Semiconductor (CMOS) sensor, etc.

[0067] In one embodiment, the processor (160) can control at least one component (e.g., one or more light sources (110), image sensors (120), conveyor belts (140), communication circuits (180)) of the device (100) connected to the processor (160) by running software (e.g., instructions, programs, etc.). The processor (160) can perform various information processing operations related to the present disclosure (e.g., determination, computation, judgment, information generation, output, modification, update, control of other components, etc.). The processor (160) can perform these operations by executing instructions stored in memory (170). That is, the processor (160) can cause the device (100) to perform each embodiment of the present disclosure according to the instructions being executed.

[0068] In one embodiment, the processor (160) may receive one or more first images from the image sensor (120). Based on the received one or more first images, the processor (160) may calculate an edge offset value representing an alignment deviation between a second substrate location, which is a predetermined location for substrate inspection, and a target printed circuit board located at the first substrate location. Based on the calculated edge offset value, the processor (160) may control the location of at least one of one or more light sources (110) or image sensors (120) during inspection of the target printed circuit board.

[0069] In the present disclosure, the processor (160) is hardware configured to perform the operations described above. The processor (160) may be a general-purpose processor capable of performing specific operations by executing instructions, or a special-purpose processor structured to perform said operations through programming. For example, the processor (160) may be a circuit comprising a CPU (Central Processing Unit), GPU (Graphics Processing Unit), NPU (Neural Processing Unit), integrated circuit, microprocessor, ASICs (Application Specific Integrated Circuits), FPGA (Field-Programmable Gate Array), conventional circuitry, or a combination thereof. That is, the processor (160) may be implemented as a circuit comprising transistors, integrated circuits, or other circuits.

[0070] The memory (170) can store various data. The data stored in the memory (170) may include software (e.g., instructions, programs, etc.) as data acquired, processed, or used by at least one component of the device (100). The memory (170) may include volatile and / or non-volatile memory. In the present disclosure, instructions or programs are software stored in the memory (170) and may include an operating system for controlling the resources of the device (100), an application, and / or middleware that provides various functions to the application so that the application can utilize the resources of the device (100). In one embodiment, the memory (170) may store instructions that cause the processor (160) to perform calculations when executed by the processor (160).

[0071] In one embodiment, the communication circuit (180) can perform wireless or wired communication between the device (100) and a server or between the device (100) and another device. For example, the communication circuit (180) can perform wireless communication according to methods such as eMBB (enhanced Mobile Broadband), URLLC (Ultra Reliable Low-Latency Communications), MMTC (Massive Machine Type Communications), LTE (Long-Term Evolution), LTE-A (LTE Advance), NR (New Radio), UMTS (Universal Mobile Telecommunications System), GSM (Global System for Mobile communications), CDMA (Code Division Multiple Access), WCDMA (Wideband CDMA), WiBro (Wireless Broadband), WiFi (Wireless Fidelity), Bluetooth, NFC (Near Field Communication), GPS (Global Positioning System), or GNSS (Global Navigation Satellite System). For example, the communication circuit (180) can perform wired communication according to methods such as USB (Universal Serial Bus), HDMI (High Definition Multimedia Interface), RS-232 (Recommended Standard-232), or POTS (Plain Old Telephone Service). In one embodiment, the processor (160) can control the communication circuit (180) to obtain information necessary to implement the technology according to the present disclosure from a server. The information obtained from the server through the communication circuit (180) can be stored in memory (170).In one embodiment, the information obtained from the server may include, for example, information on a substrate type corresponding to a target printed circuit board, and location information regarding a second substrate location within a conveyor system.

[0072] FIG. 3 is a diagram illustrating the process of a device (100) according to one embodiment of the present disclosure moving a target printed circuit board (101) from left to right and placing it at a first board position (321). In one embodiment, a processor (160) of the device (100) may move the target printed circuit board (101) from an initial position (310) to a first board position (321). The initial position (310) may represent a preset position within a conveyor system. On the other hand, the first board position (321) may represent a position where the target printed circuit board (101) moves together with the conveyor belt (140) and then stops. The first board position (321) may vary depending on the printed circuit board placed on the conveyor belt (140). For example, the first board position (321) corresponding to the target printed circuit board (101) and the first board position corresponding to a different printed circuit board may be different.

[0073] FIG. 4 is a drawing illustrating a target printed circuit board (101) according to one embodiment of the present disclosure. Referring to FIG. 4, the target printed circuit board (101) may include a first corner (102) at the bottom right, a second corner (103) at the bottom left, a third corner (104) at the top right, and a fourth corner (105) at the top left. The target printed circuit board (101) may include one or more inspection areas (411, 412). The one or more inspection areas (411, 412) included in the target printed circuit board (101) may be designed so that an imaging device (130) can easily identify them. The one or more inspection areas (411, 412) may play an important role in determining the placement position or rotation status of the printed circuit board during the inspection process of the printed circuit board, and for this purpose, each of the one or more inspection areas (411, 412) may include a fiducial mark. A fiducial mark is an element that provides a reference point for position recognition on a printed circuit board and can be configured in a geometric shape so that the processor (160) can easily detect it. Commonly used shapes of fiducial marks include circles, crosses, triangles, etc., and the shape of the fiducial mark can be selected considering both ease of recognition and ease of the manufacturing process. The processor (160) can determine the accurate placement state of the target printed circuit board (101) by using one or more inspection areas (411, 412) included in the target printed circuit board (101) captured by the imaging device (130). The target printed circuit board (101) may additionally include inspection areas at locations different from the inspection areas (411, 412) shown in FIG. 4.

[0074] Referring again to FIG. 3, the target printed circuit board (101) can be moved from left to right and placed at the first board position (321). That is, the initial position (310) can be located to the left of the first board position (321). First, the target printed circuit board (101) can be placed at the initial position (310). Specifically, the processor (160) can operate the conveyor belt (140) to move the target printed circuit board (101) to the initial position (310) as the target printed circuit board (101) is placed on the conveyor belt (140). For example, the placement of the target printed circuit board (101) at the initial position (310) may indicate that the first corner (102) of the target printed circuit board (101) is aligned at the initial position (310). That is, it may indicate that the first axis coordinate of the first corner (102) of the target printed circuit board (101) coincides with the first axis coordinate of the initial position (310). For example, the initial position (310) may be a specific position on the conveyor rail (150) detectable by the first sensing sensor (191). In this case, the processor (160) may move the conveyor belt (140) slowly until it receives a detection signal from the first sensing sensor (191) indicating that the target printed circuit board (101) has been detected. Then, the processor (160) may temporarily stop the movement of the conveyor belt (140) upon receiving the detection signal from the first sensing sensor (191). Accordingly, the first corner (102) of the target printed circuit board (101) may be aligned with the initial position (310). And, after the target printed circuit board (101) is placed at the initial position (310), the processor (160) can move the conveyor belt (140) again to move the target printed circuit board (101) to the first board position (321).The processor (160) can perform acceleration and deceleration on the conveyor belt (140) to move the target printed circuit board (101) from the initial position (310) to the first board position (321). The process of moving the target printed circuit board (101) from the initial position (310) to the first board position (321) is described in more detail in FIGS. 8 and 9.

[0075] In one embodiment, as the target printed circuit board (101) moves to the first board position (321), position control for the imaging device (130) can be performed. After position control for the imaging device (130) is performed, the processor (160) can irradiate one or more first pattern lights onto the edge line (331) of the target printed circuit board (101) located at the first board position (321) through one or more light sources (110).

[0076] At this time, the edge line (331) of the target printed circuit board (101) may represent an area included in the straight edge line existing on the target printed circuit board (101). Here, the straight edge line may represent a portion formed continuously in a straight line along the boundary line of the printed circuit board. For example, one side corner of the printed circuit board may be composed of a straight edge line and a curved edge line. The straight edge line may be used to accurately determine the placement position of the target printed circuit board (101). Accordingly, the second axis (e.g., y-axis) coordinate range corresponding to the edge line (331) may be included within the second axis coordinate range of the straight edge line existing on the target printed circuit board (101). In other words, the edge line (331) may represent a part of the straight edge line existing on the target printed circuit board (101). For example, if the range of 0 to 10 and 15 to 20 within the target printed circuit board (101) is the second axis coordinate range of the linear edge line, the second axis coordinate range corresponding to the edge line (331) may be, for example, 4 to 7.

[0077] In one embodiment, the processor (160) may determine location information of an edge line (331) to be captured within a target printed circuit board (101). The processor (160) may receive job data of a board type corresponding to the target printed circuit board (101) from a memory (170) or a communication circuit (180). The processor (160) may identify location information of a straight edge line included in the target printed circuit board (101) (e.g., a second axis coordinate range of 0 to 10 and 15 to 20) from the received job data. The processor (160) may determine the location information of the edge line (331) so that the location information of the edge line (331) to be captured is included in the location information of the straight edge line. The location information of the edge line (331) may, for example, represent a second axis coordinate range of the edge line (331) within the target printed circuit board (101). Subsequently, the processor (160) can control the position of the imaging device (130) so that the edge line (331) is included in the field of view (FOV) of the imaging device (130) (i.e., one or more light sources (110) and image sensors (120)). For example, the processor (160) can move the imaging device (130) within a plane parallel to the movement plane of the conveyor belt (140) (i.e., the plane on which the target printed circuit board (101) is placed) so that the edge line (331) is included in the field of view of the imaging device (130). In other words, the processor (160) can perform horizontal position control for the imaging device (130). Here, controlling the position of the imaging device (130) may indicate controlling the position of at least one of one or more light sources (110) or image sensors (120) included in the imaging device (130).

[0078] In one embodiment, the image sensor (120) can generate one or more first images (e.g., first images (340)) by capturing one or more first reflected light generated by one or more first patterned light being reflected from the edge line (331) of the target printed circuit board (101). In other words, one or more light sources (110) irradiate one or more first patterned light onto a surrounding area including the edge line (331) of the target printed circuit board (101), and the image sensor (120) can generate one or more first images (e.g., first images (340)) by capturing one or more first reflected light reflected from the edge line (331) and the surrounding area. Each of the one or more first images (e.g., first images (340)) may include the edge line (331). The image sensor (120) can transmit the generated one or more first images (e.g., first images (340)) to a processor (160).

[0079] In one embodiment, the processor (160) can identify a preset second substrate location (322) and an edge line (331) included in the target printed circuit board (101) in each of one or more first images (e.g., first image (340)) received from the image sensor (120). Additionally, the processor (160) can calculate an edge offset value (350) of the target printed circuit board (101) based on the difference between the first axis coordinate of the second substrate location (322) and the first axis coordinate corresponding to the edge line (331) within each first image. Hereinafter, for convenience of explanation, the process of the processor (160) identifying the preset second substrate location (322) and the edge line (331) of the target printed circuit board (101) within the first image (340) will be mainly described.

[0080] In one embodiment, the processor (160) may receive information regarding a preset second substrate location (322) from a memory (170) or a communication circuit (180). For example, the processor (160) may receive coordinate information corresponding to the second substrate location (322). The coordinate information corresponding to the second substrate location (322) may include a first axis coordinate and a second axis coordinate. Since one or more first pattern lights are irradiated after the position of the imaging device (130) is controlled by the processor (160) to generate a first image (340), the processor (160) may identify the second substrate location (322) within the first image (340). For example, referring to FIG. 3, the processor (160) can control the center of the image-capable area of ​​the image device (130) to a second substrate position (322) and then perform an image of the edge line (331) of the target printed circuit board (101). In this case, the processor (160) can determine the center of the first image (340) to the second substrate position (322) within the first image (340). As another example, the processor (160) can calculate the position difference between the center of the image-capable area of ​​the image device (130) and the second substrate position (322) when the image device (130) performs an image of the edge line (331) of the target printed circuit board (101). In this case, the processor (160) can determine the second substrate position (322) within the first image (340) by reflecting the position difference calculated from the center of the first image (340).

[0081] In one embodiment, the processor (160) can identify an edge line (331) of a target printed circuit board (101) within a first image (340). Referring to FIG. 3, the processor (160) can identify the edge line (331) by analyzing color differences within the first image (340). For example, image processing techniques may be primarily utilized in the process of identifying the edge line (331). The processor (160) can detect a boundary line with a stark difference in color or brightness to find a sudden change in pixel values ​​within the first image (340). To this end, image processing algorithms such as Sobel, Prewitt, or Canny edge detection algorithms may be used. These algorithms calculate a derivative value for each pixel of the image and determine a part where the change in color or brightness is sudden as an edge. Additionally, the processor (160) can identify the edge line (331) more accurately by identifying a different unique color pattern that is distinct from the background of the target printed circuit board (101). However, the method of identifying the edge line (331) within the first image (340) may be performed using other image processing techniques in addition to the algorithm.

[0082] In one embodiment, the processor (160) can calculate an edge offset value (350) based on the difference between the first axis coordinate of the second substrate position (322) in the first image (340) and the first axis coordinate corresponding to the edge line (331). The processor (160) can calculate the edge offset value (350) by subtracting the first axis coordinate corresponding to the edge line (331) from the first axis coordinate of the second substrate position (322) in the first image (340). For example, the first axis coordinate of the second substrate position (322) in the first image (340) may be 7.8 mm and the first axis coordinate corresponding to the edge line (331) may be 8.0 mm. In this case, the processor (160) can calculate the edge offset value (350) for the target printed circuit board (101) as -0.2 mm, which is obtained by subtracting 8.0 mm from 7.8 mm.

[0083] Furthermore, the processor (160) can calculate an edge offset value (350) of a target printed circuit board (101) through one or more first images generated by the image sensor (120). The processor (160) can identify a second board position and an edge line within each first image and calculate the difference between a first axis coordinate of the second board position within the first image and a first axis coordinate corresponding to the edge line. The processor (160) can calculate an edge offset value (350) of the target printed circuit board (101) using the corresponding difference values ​​calculated in each of the one or more first images. For example, the processor (160) can calculate an edge offset value (350) of the target printed circuit board (101) as the average value of the corresponding difference values.

[0084] FIG. 5 is a diagram illustrating the process of a device (100) according to one embodiment of the present disclosure moving a target printed circuit board (101) from right to left and placing it at a first board position (521). In one embodiment, the processor (160) of the device (100) can move the target printed circuit board (101) from an initial position (510) to a first board position (521). At this time, the target printed circuit board (101) can be moved from right to left and placed at the first board position (521). That is, the initial position (510) can be located to the right of the first board position (521).

[0085] In one embodiment, the processor (160) can perform position control for the imaging device (130) as the target printed circuit board (101) moves to a first substrate position (521). For example, the processor (160) can move the imaging device (130) within a plane parallel to the movement plane of the conveyor belt (140) so that the edge line (531) of the target printed circuit board (101) is included in the imageable area of ​​the imaging device (130). After position control for the imaging device (130) is performed, the processor (160) can irradiate one or more first pattern lights onto the edge line (531) of the target printed circuit board (101) located at the first substrate position (521) through one or more light sources (110). The image sensor (120) can generate one or more first images (e.g., first images (540)) by capturing one or more first reflected light generated by one or more first pattern light being reflected from the edge line (531) of the target printed circuit board (101).

[0086] In one embodiment, the processor (160) can calculate an edge offset value (550) based on the difference between the first axis coordinate of the second substrate location (522) in the first image (540) and the first axis coordinate corresponding to the edge line (531). For example, the processor (160) can calculate the edge offset value (550) by subtracting the first axis coordinate corresponding to the edge line (531) from the first axis coordinate of the second substrate location (522) in the first image (540).

[0087] In one embodiment, the processor (160) can calculate an edge offset value for a target printed circuit board (101) by subtracting a first axis coordinate corresponding to an edge line (e.g., edge line (331) of FIG. 3, edge line (531) of FIG. 5) from a first axis coordinate of a second substrate position (e.g., second substrate position (322) of FIG. 3, edge line (522) of FIG. 5)) within a first image (e.g., first image (340) of FIG. 3, first image (540) of FIG. 5) regardless of whether the initial position (e.g., initial position (310) of FIG. 3, initial position (510) of FIG. 5)) is located to the right or left relative to the first substrate position (e.g., first substrate position (321) of FIG. 3, first substrate position (521) of FIG. 5). Hereinafter, for the convenience of explanation, the case in which the target printed circuit board (101) moves from left to right and is placed at the first board position (321) is mainly described.

[0088] FIG. 6 is a diagram illustrating the process of a device according to one embodiment of the present disclosure capturing one or more inspection areas (411, 412) included in a target printed circuit board (101) and calculating a fiducial offset. In one embodiment, the processor (160) of the device (100) may calculate an edge offset value (350) of the target printed circuit board (101) based on one or more first images (340), and then calculate a fiducial offset to determine the accurate placement position of the target printed circuit board (101). The fiducial offset may represent a position correction value associated with a fiducial mark included in the printed circuit board.

[0089] In one embodiment, the target printed circuit board (101) may include one or more inspection areas (411, 412) located at the upper edge of the target printed circuit board (101). The one or more inspection areas (411, 412) may be located at the same edge or different edges. For example, the first inspection area (411) may be located at the first corner area of ​​the target printed circuit board (101), and the second inspection area (412) may be located at the second corner area of ​​the target printed circuit board (101). The first corner area may represent an area that is closer to the second corner (103) compared to other corners among the areas constituting the target printed circuit board (101). The second corner area may represent an area that is closer to the third corner (104) compared to other corners among the areas constituting the target printed circuit board (101). Additionally, the second corner area may be an area symmetrical to the first corner area with respect to the center of the target printed circuit board (101). In this specification, one or more inspection areas (411, 412) included in the target printed circuit board (101) are described as being mainly located in the first corner area and the second corner area, but are not limited thereto, and additional inspection areas may be located in other corner areas.

[0090] In one embodiment, the processor (160) may move one or more light sources (110) and image sensors (120) to a second location that reflects an edge offset value (350) for the target printed circuit board (101) from a first location corresponding to each inspection area (e.g., a first inspection area (411)). The processor (160) may obtain one or more second images by capturing each inspection area (e.g., a first inspection area (411)) through an imaging device (130) at the second location. Here, the first location corresponding to the inspection area may represent coordinate information of the inspection area assuming a state in which the target printed circuit board (101) is placed at a second board location (322). Since each inspection area may have a different location within the target printed circuit board (101), the first location corresponding to each inspection area may also be different. Additionally, since the first location corresponding to each inspection area is different, the second location corresponding to each inspection area may also be different. For example, the processor (160) may move one or more light sources (110) and image sensors (120) to a second position corresponding to a first inspection area (411) located in a first corner area, and capture the first inspection area (411) to obtain one second image. Similarly, the processor (160) may move one or more light sources (110) and image sensors (120) to a second position corresponding to a second inspection area (412) located in a second corner area, and capture the second inspection area (412) to obtain another second image.

[0091] Hereinafter, the process of the processor (160) calculating a second position corresponding to the first inspection area (411) is described by example. First, the processor (160) can calculate a first position corresponding to the first inspection area (411). The first position corresponding to the first inspection area (411) may represent coordinate information of the first inspection area (411) assuming a state in which the target printed circuit board (101) is placed at the second board position (322). For example, the fact that the target printed circuit board (101) is placed at the second board position (322) may indicate that the midpoint of the first corner (102) and the third corner (104) of the target printed circuit board (101) is aligned with the second board position (322). In other words, it may indicate that the coordinate information of the midpoint of the first corner (102) and the third corner (104) of the target printed circuit board (101) matches the coordinate information of the second board position (322). The processor (160) can identify location information of a first inspection area (411) within a target printed circuit board (101) from substrate information corresponding to the substrate type of the target printed circuit board (101). For example, the processor (160) can calculate relative location information of the first inspection area (411) within the target printed circuit board (101) based on the midpoint of the first corner (102) and the third corner (104). Then, the processor (160) can calculate a first location by reflecting the relative location information of the first inspection area (411) in the coordinate information of a second substrate location (322). The first location may include a first axis coordinate and a second axis coordinate. Additionally, the processor (160) can calculate a second location by reflecting the edge offset value (350) of the target printed circuit board (101) in the first location. For example, the processor (160) can calculate a second position by subtracting an edge offset value (350) (e.g., -0.2 mm) from the first axis coordinate of the first position.Here, to calculate the first position, it is assumed that the target printed circuit board (101) is placed at the second board position (322), but in reality, since the target printed circuit board (101) is placed at the first board position (321), an edge offset value (350) can be reflected for the first position to calculate the second position.

[0092] In one embodiment, the processor (160) can calculate a fiducial offset for a target printed circuit board (101) through one or more second images obtained by capturing one or more inspection areas (411, 412). At this time, the fiducial offset may be composed of a value of a first axis coordinate and a value of a second axis coordinate. For example, the processor (160) can identify the first inspection area (411) and the second corner (103) from the second image obtained by capturing the first inspection area (411). The processor (160) can calculate coordinate information of the first fiducial mark by using the relative positional relationship that the first fiducial mark included in the first inspection area (411) has with the first corner (102) within the second image. Additionally, the processor (160) can identify the second inspection area (412) and the third corner (104) from another second image obtained by capturing the second inspection area (412). The processor (160) can calculate coordinate information of the second fiducial mark by using the relative positional relationship between the second fiducial mark included in the second inspection area (412) and the third corner (104) within the second image. Based on the relative positional information between the first fiducial mark and the second fiducial mark, the processor (160) can calculate a fiducial offset including rotational offset, translation, twisting, etc. of the target printed circuit board (101).

[0093] For example, the processor (160) can calculate the theoretical first center coordinates of the target printed circuit board (101) based on the first fiducial mark, based on substrate information of the substrate type corresponding to the target printed circuit board (101). Additionally, the processor (160) can calculate the actual second center coordinates based on the first fiducial mark and the second fiducial mark. For example, the processor (160) can calculate the second center coordinates based on the first fiducial mark and the second fiducial mark. The processor (160) can calculate the fiducial offset for the target printed circuit board (101) by calculating the difference between the first center coordinates and the second center coordinates for each coordinate axis. However, the method of calculating the fiducial offset is not limited to the above examples.

[0094] In one embodiment, the processor (160) can control the position of at least one of one or more light sources (110) or image sensors (120) during inspection of a target printed circuit board (101) based on an adjustment value obtained by summing the fiducial offset and edge offset values. As described above, the fiducial offset may consist of a value of a first axis coordinate and a value of a second axis coordinate. On the other hand, since the edge offset value represents the difference between the first axis coordinate of the second board position (322) and the first axis coordinate corresponding to the edge line (331), the edge offset value may include only the value of the first axis coordinate. Accordingly, the adjustment value obtained by summing the fiducial offset and edge offset values ​​may consist of a first axis coordinate value and a second axis coordinate value. The first axis coordinate value of the adjustment value may be the sum of the first axis coordinate value corresponding to the fiducial offset and the edge offset value, and the second axis coordinate value of the adjustment value may be the second axis coordinate value corresponding to the fiducial offset.

[0095] In one embodiment, the processor (160) can control the position of at least one of one or more light sources (110) or image sensors (120) during inspection of the target printed circuit board (101) according to an adjustment value. Specifically, the processor (160) assumes that the target printed circuit board (101) is aligned with the second board position (322) and can align the center of the imageable area formed by the imaging device (130) with the reference position. In this case, the processor (160) can calculate a new adjustment position by reflecting the adjustment value to the reference position and control the position of the imaging device (130) so that the center of the imageable area formed by the imaging device (130) aligns with the calculated adjustment position. In another example, the processor (160) can separate and image individual parts of the target printed circuit board (101) multiple times for inspection of the target printed circuit board (101). At this time, multiple reference positions may be set, and the processor (160) may calculate multiple adjustment positions by reflecting an adjustment value for each reference position. Then, the processor (160) may control the position of the imaging device (130) so that the center of the imaging area formed by the imaging device (130) coincides with each adjustment position, and may capture the target printed circuit board (101) at the controlled position to obtain an image for inspection of the target printed circuit board.

[0096] FIG. 7 is a drawing illustrating the process of a device (100) according to one embodiment of the present disclosure controlling the position of an imaging device (130).

[0097] In one embodiment, the processor (160) of the device (100) can move one or more light sources (110) and image sensors (120) within a plane (710) parallel to the movement plane of the conveyor belt (140) so that as the target printed circuit board (101) reaches a first board position (321), the edge line (331) of the target printed circuit board (101) is included in the imaging observation area (720) of the imaging device (130). That is, the imaging device (130) can be adjusted by moving it within a plane (710) parallel to the upper surface of the conveyor rail (150). The processor (160) can obtain one or more first images by capturing the edge line (331) of the target printed circuit board (101) at the adjusted position, and can calculate an edge offset value (350) for the target printed circuit board (101) through the one or more first images obtained.

[0098] In one embodiment, the processor (160) may calculate an edge offset value (350) and then calculate a fiducial offset. Specifically, the processor (160) may move one or more light sources (110) and image sensors (120) to a second position corresponding to a first inspection area (411) located in a first corner area. For example, the processor (160) may move one or more light sources (110) and image sensors (120) within a plane (710) parallel to the movement plane of the conveyor belt (140) so that the first inspection area (411) and the second corner (103) are included in the imaging observation area (730) of the imaging device (130). Additionally, the processor (160) may move one or more light sources (110) and image sensors (120) to a second position corresponding to a second inspection area (412) located in a second corner area. For example, the processor (160) can move one or more light sources (110) and image sensors (120) within a plane (710) parallel to the movement plane of the conveyor belt (140) so that the second inspection area (412) and the third corner (104) are included in the imaging observation area (740) of the imaging device (130). The processor (160) can calculate a fiducial offset for the target printed circuit board (101) through a plurality of second images obtained by imaging the first inspection area (411) and the second inspection area (412), respectively.

[0099] FIG. 8 is a diagram illustrating the process of moving a target printed circuit board (101) to a first board position (321) by a device (100) according to one embodiment of the present disclosure. In one embodiment, a processor (160) of the device (100) may operate a conveyor belt (140) to move the target printed circuit board (101) from an initial position (310) to a first board position (321).

[0100] Referring to FIG. 8, the target printed circuit board (101) may be placed at an initial position (310). As illustrated in FIG. 3, the initial position (310) may be a specific location on the conveyor rail (150) detectable by the first sensing sensor (191). At the time the target printed circuit board (101) is placed at the initial position (310), the conveyor belt (140) may be in a stationary state. Upon receiving a signal from the first sensing sensor (191) detecting the target printed circuit board (101), the processor (160) may gradually accelerate the stationary conveyor belt (140) to a first speed. For example, the processor (160) may accelerate the conveyor belt (140) from a stationary state (e.g., a speed of '0') to a first speed. The processor (160) may accelerate the conveyor belt (140) from a stationary state to a first speed by applying a constant acceleration. However, it is not limited to this, and the processor (160) may also accelerate the conveyor belt (140) by applying an acceleration that changes over time. Additionally, the processor (160) may accelerate the conveyor belt (140) from a stationary state to a first speed, and then move the conveyor belt (140) at the first speed for a certain period of time. For example, the speed of the conveyor belt (140) may reach the first speed before the detection of the target printed circuit board (101) by the first detection sensor (191) is finished.

[0101] In one embodiment, the target printed circuit board (101) may move along with the movement of the conveyor belt (140). Additionally, as the target printed circuit board (101) moves, the second sensing sensor (192) may detect at least a portion of the target printed circuit board (101). At the point when the second sensing sensor (192) detects at least a portion of the target printed circuit board (101), the conveyor belt (140) may be moving at a second speed lower than the first speed. At this time, upon receiving a signal from the second sensing sensor (192) detecting the target printed circuit board (101), the processor (160) may gradually decelerate the conveyor belt (140) from the second speed and stop it. As the conveyor belt (140) stops, the target printed circuit board (101) may also stop, and consequently, the target printed circuit board (101) may be placed at the first board position (321). For example, the processor (160) can decelerate the conveyor belt (140) from a second speed to a stop state (e.g., a speed of '0'). The processor (160) can decelerate the conveyor belt (140) from a second speed to a stop state by applying a constant acceleration. However, it is not limited to this, and the processor (160) may also decelerate the conveyor belt (140) by applying an acceleration that changes over time.

[0102] More specifically, the processor (160) can move the conveyor belt (140) by a preset first distance (801) at a first speed when the signal detecting the target printed circuit board (101) received from the first detection sensor (191) is interrupted. For example, when the target printed circuit board (101) moves from left to right and is placed at the first board position (321), the first detection sensor (191) can stop generating the signal detecting the target printed circuit board (101) after detecting the second corner (103) of the target printed circuit board (101).

[0103] Accordingly, the processor (160) can move the conveyor belt (140) by a preset first distance (801) and then move the conveyor belt (140) by decelerating it from a first speed to a second speed. For example, the processor (160) can apply a constant acceleration during the process of decelerating the conveyor belt (140) from a first speed to a second speed. Additionally, the processor (160) can move the conveyor belt (140) at the second speed for a certain period of time after decelerating the conveyor belt (140) from a first speed to a second speed. For example, the processor (160) can move the conveyor belt (140) by maintaining it at the second speed until it receives a signal from the second detection sensor (192) detecting at least a part of the target printed circuit board (101). In other words, the conveyor belt (140) can move at a second speed after starting to decelerate from the first speed at a first speed for a preset first distance (801) at a time point (t1), and then maintaining the second speed until a signal detecting the target printed circuit board (101) is received from the second detection sensor (192) at a time point (t2). Hereinafter, t1 is described as the time point of deceleration of the conveyor belt (140) and t2 as the time point of detection by the second detection sensor (192). The distance (802) in FIG. 8 may represent the distance traveled by the conveyor belt (140) from the time point of deceleration (t1) to the time point of detection (t2). Additionally, the section (812) may represent a set of locations where the second detection sensor (192) can perform detection of the printed circuit board. In other words, when at least a portion of the target printed circuit board (101) enters the section (812), the second detection sensor (192) can generate a signal to detect the target printed circuit board (101).

[0104] FIG. 9 illustrates a graph showing the speed of a conveyor belt (140) over time according to one embodiment of the present disclosure. Referring to FIG. 9, at the point (911) when a target printed circuit board (101) is placed at an initial position (310), the conveyor belt (140) may be in a stationary state. As the processor (160) receives a signal detecting the target printed circuit board (101) from the first detection sensor (191), the conveyor belt (140) may be gradually accelerated to a first speed. The conveyor belt (140) may move at the first speed from the point (912) when acceleration to the first speed is completed. Subsequently, the conveyor belt (140) may move at the first speed for a preset first distance (801) from the point (913) when detection of the target printed circuit board (101) by the first detection sensor (191) is stopped.

[0105] In one embodiment, the conveyor belt (140) may begin decelerating from a first speed to a second speed at a point (e.g., deceleration point (t1)) after moving a preset first distance (801) from the point (913) when detection of the target printed circuit board (101) by the first detection sensor (191) is stopped. The conveyor belt (140) may move at a second speed from the point (914) when deceleration to the second speed is completed. Afterward, the conveyor belt (140) may continue to move while maintaining the second speed until the point (e.g., detection point (t2)) when the second detection sensor (192) begins to detect the target printed circuit board (101). The conveyor belt (140) may decelerate from the second speed to a stop state after a certain amount of time has elapsed from the point (e.g., detection point (t2)) when the second detection sensor (192) begins to detect the target printed circuit board (101). However, this is not limited thereto, and the conveyor belt (140) may be decelerated from the second speed to a stop state immediately from the point when the second detection sensor (192) begins to detect the target printed circuit board (101) (e.g., detection time (t2)).

[0106] Referring again to FIG. 8, the processor (160) can calculate a preset first distance (801). Here, the first distance (801) may represent the distance traveled by the conveyor belt (140) from the point (913) when detection of the target printed circuit board (101) from the first detection sensor (191) is stopped until the point (t1) of deceleration. At this time, the processor (160) can calculate the first distance (801) by subtracting the length corresponding to the first axis of the target printed circuit board (e.g., 'h'), the travel distance required to decelerate from the first speed to the second speed, and the minimum distance required to travel at the second speed from the distance (803) from the first detection sensor (191) to the second detection sensor (192). For example, the sum of the travel distance required to decelerate from the first speed to the second speed and the minimum distance required to travel at the second speed may represent the distance (802).

[0107] In one embodiment, the processor (160) can determine the deceleration time (t1) by calculating a preset first distance (801). For example, the processor (160) can calculate the time to travel at the first speed by dividing the first distance (801) by the first speed, and determine the time after which the time calculated from the time (913) when the detection of the target printed circuit board (101) by the first detection sensor (191) is stopped is the deceleration time (t1) of the conveyor belt (140). Specifically, the processor (160) can determine the deceleration time (t1) of the conveyor belt (140) at the time (913) when the detection of the target printed circuit board (101) by the first detection sensor (191) is stopped.

[0108] In one embodiment, since the first speed is greater than the second speed, the greater the first distance (801), which is the distance traveled at the first speed, the shorter the time required to move the target printed circuit board (101) from the initial position (310) to the first substrate position (321). This may indicate that the time required to inspect the target printed circuit board (101) can be reduced. Accordingly, the processor (160) may maximize the first distance (801) by moving the minimum distance at the second speed. For example, the processor (160) may cause the conveyor belt (140) to move at the second speed for a preset time (e.g., 0.3 seconds) until it receives a signal detecting the target printed circuit board (101) from the second detection sensor (192). In this case, the minimum distance to be moved at the second speed may be the distance calculated by multiplying the second speed by the preset time (e.g., 0.3 seconds). In another example, the processor (160) may cause the conveyor belt (140) to move a preset distance (e.g., 300 mm) at a second speed until it receives a signal from the second sensing sensor (192) detecting the target printed circuit board (101). In this case, the minimum distance to be moved at the second speed may be 300 mm.

[0109] In one embodiment, the processor (160) slows down the speed of the conveyor belt (140) to reach a stop state after the second sensing sensor (192) detects at least a portion of the target printed circuit board (101). At this time, if the conveyor belt (140) moves at a high speed, such as the first speed, before slowing down, the first board position, which is the position where the target printed circuit board (101) stops, may be too far from the position where the second sensing sensor (192) can detect it. This may cause the problem of having to unnecessarily increase the length of the conveyor system. Additionally, when the conveyor belt (140) slows down while moving at high speed, the problem may also occur where the target printed circuit board (101) moves further due to the high speed of slowdown. Accordingly, the processor (160) can reduce the speed of the conveyor belt (140) from the first speed to the second speed before the second detection sensor (192) detects at least a portion of the target printed circuit board (101), thereby ensuring that the position where the target printed circuit board (101) stops is not far from the position where the second detection sensor (192) can detect.

[0110] In one embodiment, the processor (160) can control the movement of the conveyor belt (140) using a plurality of sensing sensors (191, 192, 193) included in the conveyor system. By moving the conveyor belt (140) in this way, the target printed circuit board (101) can be moved from the initial position (310) to the first board position (321). As a result, the device (100) can place the target printed circuit board (101) at a designated position and perform inspection without using pneumatic pressure, which has the advantage of enabling cost reduction.

[0111] FIG. 10 is a drawing that explains in more detail the process of a device (100) according to one embodiment of the present disclosure slowing down the speed of a target printed circuit board (101).

[0112] In one embodiment, the processor (160) of the device (100) may move the conveyor belt (140) by a preset second distance (1001) at a second speed upon receiving a signal detecting the target printed circuit board (101) from the second detection sensor (192), and then gradually reduce the speed to stop. In other words, the processor (160) may move the conveyor belt (140) by a preset second distance (1001) from the point in time when it receives a signal detecting the target printed circuit board (101) from the second detection sensor (192) (e.g., detection point (t2) in FIG. 9). Here, the preset second distance (1001) may be 30 mm, but is not limited thereto. The processor (160) can reduce the speed of the conveyor belt (140) from the second speed to a stop state (e.g., speed of '0') from the time of detection (t2) and from the time of moving the conveyor belt (140) by a preset second distance (1001) at the second speed (t3).

[0113] In one embodiment, the processor (160) can determine whether a signal detecting the target printed circuit board (101) is continuously received from the second detection sensor (192) from the detection point (t2) until the point (t3) when the conveyor belt (140) has traveled a preset second distance (1001) at a second speed. If the signal detecting the target printed circuit board (101) is interrupted during the time interval from the detection point (t2) to the point (t3), the processor (160) may not perform deceleration on the conveyor belt (140).

[0114] For example, the second detection sensor (192) may incorrectly detect an object other than the target printed circuit board (101) or generate an incorrect signal and transmit it to the processor (160). Therefore, if the signal detecting at least a part of the target printed circuit board (101) from the second detection sensor (192) is interrupted during the time interval from the detection time (t2) to the time (t3), this may indicate that the second detection sensor (192) did not actually detect at least a part of the target printed circuit board (101) but transmitted a different signal. In other words, if the signal detecting at least a part of the target printed circuit board (101) is not interrupted during the time interval from the detection time (t2) to the time (t3), the processor (160) can determine that the second detection sensor (192) has detected at least a part of the target printed circuit board (101). And, the processor (160) can decelerate the conveyor belt (140) from the second speed to a stop state from the point (t3) when the conveyor belt (140) has traveled a preset second distance (1001) at the second speed. In summary, the processor (160) can accurately place the target printed circuit board (101) at the first board position (321) by determining whether a signal detecting at least a part of the target printed circuit board (101) is continuously received from the second detection sensor (192) during the time interval from the detection point (t2) to the point (t3).

[0115] FIG. 11 is a diagram illustrating the process of a device (100) according to one embodiment of the present disclosure performing a pre-run operation. In one embodiment, the device (100) must check whether another printed circuit board (1101) exists on the conveyor belt (140) before the target printed circuit board (101) is placed on the conveyor belt (140). If another printed circuit board (1101) exists on the conveyor belt (140), the device must perform an inspection of the other printed circuit board (1101) and then perform an inspection of the target printed circuit board (101). The following describes the process for inspecting another printed circuit board (1101) that has been placed on the conveyor belt (140) in advance.

[0116] In one embodiment, the processor (160) of the device (100) may move the conveyor belt (140) at a preset speed (e.g., a second speed) before placing the target printed circuit board (101) on the conveyor belt (140). During the process of moving the conveyor belt (140) for a preset time or a preset distance, if the processor (160) does not receive a signal detecting another printed circuit board (1101) from the second detection sensor (192), it may determine that there is no other printed circuit board (1101) on the conveyor belt (140). On the other hand, the processor (160) may receive a signal detecting another printed circuit board (1101) from the second detection sensor (192). The following describes the case where the processor (160) receives a signal detecting another printed circuit board (1101) from the second detection sensor (192).

[0117] In one embodiment, the processor (160) may stop the conveyor belt (140) upon receiving a signal from the second detection sensor (192) detecting another printed circuit board (1101). Then, the processor (160) may move the conveyor belt (140) in the reverse direction so that the reception of the signal from the second detection sensor (192) detecting another printed circuit board (1101) is stopped. The processor (160) may move the conveyor belt (140) in the reverse direction by a certain distance, and then move the conveyor belt (140) in the forward direction. Then, the processor (160) may stop the conveyor belt (140) upon receiving a signal from the second detection sensor (192) detecting another printed circuit board (1101). At this time, the processor (160) can generate one or more first images by irradiating pattern light onto the edge lines of another printed circuit board (1101) placed on the conveyor belt (140), and can calculate an edge offset value for the other printed circuit board (1101) based on the generated one or more first images. The processor (160) can control the position of at least one of one or more light sources (110) or image sensors (120) according to the edge offset value calculated for the other printed circuit board (1101). Then, the processor (160) can remove the other printed circuit board (1101) from the conveyor belt (140) after performing an inspection by capturing the other printed circuit board (101) through one or more light sources (110) and image sensors (120) at the controlled positions. For example, the processor (160) can detect the removal of the other printed circuit board (1101) by receiving a signal generated by a third detection sensor (193). After another printed circuit board (1101) is removed from the conveyor belt (140), the processor (160) can place the target printed circuit board (101) on the conveyor belt (140) and perform an inspection on the target printed circuit board (101).

[0118] FIG. 12 illustrates a graph showing the speed over time of a conveyor belt (140) for inspecting another printed circuit board (1101) according to one embodiment of the present disclosure. In one embodiment, a processor (160) may move the conveyor belt (140) by accelerating it in the reverse direction at a third speed. The third speed may represent a negative speed. The processor (160) may accelerate the conveyor belt (140) in the reverse direction by applying a constant acceleration at the third speed from a stationary state. At this time, the processor (160) may move the conveyor belt (140) in the reverse direction so that the reception of a signal detecting another printed circuit board (1101) from the second detection sensor (192) is interrupted. Here, the forward direction is the main direction of movement of the conveyor belt (140) and may represent the direction from the initial position (310) toward the first board position (321). The reverse direction may represent the opposite direction of the forward direction.

[0119] And, the processor (160) can accelerate the conveyor belt (140) from a third speed in the reverse direction to a fourth speed in the forward direction. The fourth speed may represent a positive speed. At this time, the fourth speed may be set to a smaller size than the third speed. While moving the conveyor belt (140) at the fourth speed in the forward direction, the processor (160) may receive a signal again from the second detection sensor (192) detecting another printed circuit board (1101). Upon receiving the signal again from the second detection sensor (192) detecting another printed circuit board (1101), the processor (160) may decelerate the conveyor belt (140) from the fourth speed and stop it. At this time, upon receiving the signal again from the second detection sensor (192) detecting another printed circuit board (1101), the processor (160) may immediately decelerate the conveyor belt (140) from the fourth speed to a stop state. However, not limited thereto, the processor (160) may decelerate from a fourth speed to a stop state after a preset time has elapsed from the time (1201) when the signal is received from the second detection sensor (192) that detects another printed circuit board (1101), or after moving the conveyor belt (140) by a preset distance. The processor (160) may perform an inspection of the other printed circuit board (1101) at the location where the other printed circuit board (1101) has stopped.

[0120] FIGS. 13 and FIGS. 14 are flowcharts schematically illustrating the operation performed by the device (100) according to one embodiment of the present disclosure.

[0121] Referring to FIG. 13, in operation (S1310), the processor (160) of the device (100) can operate the conveyor belt (140) to move the target printed circuit board (101) to the first board position (321). Specifically, the processor (160) can operate the conveyor belt (140) to move the target printed circuit board (101) from the initial position (310) to the first board position (321). The processor (160) can perform acceleration and deceleration on the conveyor belt (140).

[0122] In operation (S1320), the processor (160) can control one or more light sources (110), and one or more light sources (110) can irradiate one or more first pattern lights on the edge line (331) of the target printed circuit board (101) located at the first substrate position (321).

[0123] In operation (S1330), the processor (160) can control the image sensor (120), and the image sensor (120) can capture one or more first reflected light generated by being reflected from the edge line (331) of the target printed circuit board (101) to generate one or more first images (e.g., first images (340)).

[0124] In operation (S1340), the processor (160) can calculate an edge offset value (350) representing the alignment deviation between the target printed circuit board (101) located at the first substrate position (321) and the second substrate position (322), which is a predetermined position. For example, the processor (160) can calculate the edge offset value (350) by subtracting the first axis coordinate corresponding to the edge line (331) from the first axis coordinate of the second substrate position (322) within the first image (340).

[0125] In operation (S1350), the processor (160) can control the position of at least one of one or more light sources (110) or image sensors (120) during inspection of the target printed circuit board (101) according to an edge offset value (350) for the target printed circuit board (101). The processor (160) can control the position of one or more light sources (110) or image sensors (120) through position control of the imaging device (130). For example, the processor (160) may control only the position of the image sensors (120) while keeping the position of one or more light sources (110) fixed according to the edge offset value (350) for the target printed circuit board (101).

[0126] The operations (S1411), (S1412), (S1413), and (S1414) of FIG. 14 may be at least some of the operations (S1310) of FIG. 13. In operation (S1411), the processor (160) may gradually accelerate the conveyor belt (140) to a first speed as it receives a signal detecting the target printed circuit board (101) from the first sensing sensor (191). For example, the processor (160) may accelerate the conveyor belt (140) to 1 m / s 2 The conveyor belt (140) can be accelerated with a constant acceleration.

[0127] In operation (S1412), when the signal detecting the target printed circuit board (101) received from the first detection sensor (191) is interrupted, the processor (160) can move the conveyor belt (140) by a preset first distance (801) at a first speed. At this time, the preset first distance (801) may vary depending on the type of printed circuit board placed on the conveyor belt (140).

[0128] In operation (S1413), the processor (160) can move the conveyor belt (140) by decelerating it from a first speed to a second speed after the conveyor belt (140) has traveled a first distance (801). For example, the processor (160) can move the conveyor belt (140) at -1 m / s 2 The conveyor belt (140) can be decelerated with a constant acceleration. The processor (160) can make the magnitude of the acceleration when accelerating the conveyor belt (140) from a stationary state to a first speed and the magnitude of the acceleration when decelerating from the first speed to a second speed the same, but is not necessarily limited to this, and the magnitudes of the two accelerations may be different from each other.

[0129] In operation (S1414), the processor (160) may gradually decelerate the conveyor belt (140) from a second speed and stop it as it receives a signal from the second detection sensor (192) detecting the target printed circuit board (101). For example, the processor (160) may move the conveyor belt (140) by a preset second distance (1001) at a second speed, and then -1 m / s 2 The conveyor belt (140) can be decelerated with a constant acceleration.

[0130] Various embodiments of the present disclosure may be implemented as software recorded on a machine-readable recording medium. The software may be software for implementing the various embodiments of the present disclosure described above. The software may be inferred from the various embodiments of the present disclosure by programmers skilled in the art to which the present disclosure pertains. For example, the software may be a machine-readable instruction (e.g., code or code segment) or a program. The machine may be a device capable of operating according to instructions called from the recording medium, for example, a computer. In one embodiment, the machine may be a device (100) according to the embodiments of the present disclosure. In one embodiment, the processor of the machine may execute the called instruction to cause the components of the machine to perform a function corresponding to the instruction. In one embodiment, the processor may be one or more processors according to the embodiments of the present disclosure. The recording medium may mean any type of recording medium in which data is stored that can be read by the machine. The recording medium may include, for example, ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, etc. In one embodiment, the recording medium may be one or more memories. In one embodiment, the recording medium may be implemented in a distributed form in a networked computer system, etc. Software may be stored and executed in a distributed manner in a computer system, etc. The recording medium may be a non-transitory recording medium. A non-transitory recording medium refers to a tangible medium that exists regardless of whether data is stored semi-permanently or temporarily, and does not include a signal that propagates transitorily.

[0131] Although the technical concept of the present disclosure has been described by various embodiments above, the technical concept of the present disclosure includes various substitutions, modifications, and alterations that can be made within the scope of understanding of those skilled in the art to which the present disclosure pertains. Furthermore, it should be understood that such substitutions, modifications, and alterations may be included within the scope of the appended claims.

Claims

1. A conveyor belt on which a target printed circuit board (PCB) is placed and which moves the target printed circuit board to a first board position; One or more light sources that irradiate one or more first pattern lights onto the edge lines of the target printed circuit board located at the first substrate position; An image sensor that captures one or more first reflected lights generated by one or more first pattern lights being reflected from the edge line to generate one or more first images; One or more processors; and It includes one or more memories in which instructions to be executed by the above one or more processors are stored, and When executing the above instructions, the one or more processors, Based on the above one or more first images, an edge offset value representing an alignment deviation between a second substrate location, which is a predetermined location for substrate inspection, and the target printed circuit board located at the first substrate location is calculated. A device for controlling the position of at least one of the one or more light sources or the image sensor during inspection of the target printed circuit board based on the calculated edge offset value.

2. In Paragraph 1, The above one or more processors, For each of the above one or more first images, the second substrate position and the edge line are each identified, and A device for calculating an edge offset value based on the difference between a first axis coordinate of a second substrate position and a first axis coordinate corresponding to an edge line within each of the first images.

3. In Paragraph 2, The above first axis is a device representing an axis parallel to the direction of movement of the conveyor belt.

4. In Paragraph 1, A device in which the second axis coordinate range corresponding to the above edge line is included within the second axis coordinate range of the straight edge line existing on the target printed circuit board.

5. In Paragraph 1, The above one or more processors, A device for moving one or more light sources and the image sensor within a plane parallel to the movement plane of the conveyor belt so that the edge line of the target printed circuit board is included in the field of view (FOV) of the image sensor.

6. In Paragraph 1, The above target printed circuit board includes one or more inspection areas located at the upper edge of the target printed circuit board, and The above one or more processors, A device for moving one or more light sources and the image sensor from a first position corresponding to each inspection area to a second position reflecting the edge offset value, and capturing each inspection area at the second position to obtain one or more second images.

7. In Paragraph 6, The above one or more processors, An apparatus for obtaining one second image by capturing a first inspection area located in a first corner area of ​​the target printed circuit board, and obtaining another second image by capturing a second inspection area located in a second corner area symmetrical to the first corner area with respect to the center of the target printed circuit board.

8. In Paragraph 6, The above one or more processors, Calculate a fiducial offset through one or more second images obtained by capturing the above one or more inspection areas, and A device for controlling the position of at least one of the one or more light sources or the image sensor during inspection of the target printed circuit board based on an adjustment value obtained by summing the fiducial offset and the edge offset values.

9. In Paragraph 1, The above one or more processors, Upon receiving a signal detecting the target printed circuit board from the first sensing sensor, the conveyor belt is gradually accelerated to a first speed, and A device that, upon receiving a signal detecting the target printed circuit board from a second detection sensor, gradually decelerates the conveyor belt from a second speed lower than the first speed and stops it.

10. In Paragraph 9, The above one or more processors, When the signal detecting the target printed circuit board received from the first detection sensor is interrupted, the conveyor belt is moved by a preset first distance at the first speed, and A device for moving the conveyor belt by decelerating it from the first speed to the second speed after the conveyor belt has traveled the first distance.

11. In Paragraph 10, The above one or more processors, A device for calculating a first distance by subtracting the length of the target printed circuit board, the distance required to decelerate from the first speed to the second speed, and the minimum distance required to travel at the second speed from the distance from the first sensing sensor to the second sensing sensor.

12. In Paragraph 9, The above one or more processors, A device that, upon receiving a signal detecting the target printed circuit board from the second sensing sensor, moves the conveyor belt by a preset second distance at the second speed and then gradually decelerates the speed to stop.

13. In Paragraph 9, The above one or more processors, If a signal detecting another printed circuit board is received from the second detection sensor before the above target printed circuit board is placed, the conveyor belt is moved in the reverse direction at a third speed, and then the conveyor belt is accelerated in the forward direction to a fourth speed. A device that, when a signal detecting the other printed circuit board is received again from the second detection sensor, slows down the conveyor belt from the fourth speed and stops it.

14. In Paragraph 13, The above fourth speed is a device that is set to a size smaller than the above third speed.

15. In a method for inspecting a printed circuit board, A step of placing a target printed circuit board and moving the target printed circuit board to a first board position; A step of irradiating one or more first pattern lights onto the edge lines of the target printed circuit board located at the first substrate position; A step of generating one or more first images by capturing one or more first reflected lights generated by the reflection of one or more first pattern lights from the edge line; Based on the above one or more first images, a step of calculating an edge offset value representing an alignment deviation between a second substrate location, which is a predetermined location for substrate inspection, and the target printed circuit board located at the first substrate location; and A method comprising the step of controlling the position of at least one of the one or more light sources or the image sensor during inspection of the target printed circuit board according to the calculated edge offset value.

16. A non-transient computer-readable recording medium having recorded instructions that cause one or more processors to perform an operation when executed by one or more processors, The above instructions cause the above one or more processors, A target printed circuit board is placed, and the target printed circuit board is moved to a first board position, and One or more first pattern lights are irradiated onto the edge lines of the target printed circuit board located at the first substrate position, and One or more first pattern lights are reflected from the edge line to generate one or more first reflected lights, and one or more first images are generated by capturing one or more first reflected lights. Based on the above one or more first images, an edge offset value representing an alignment deviation between a second substrate location, which is a predetermined location for substrate inspection, and the target printed circuit board located at the first substrate location is calculated, and A non-transient computer-readable recording medium that controls the position of at least one of the one or more light sources or the image sensor during inspection of the target printed circuit board according to the calculated edge offset value.

Images