A circuit, light source, phase skew detection device, and electronic device

Abstract

The utility model discloses a kind of circuit, light source, phase deflection detection device and electronic equipment, the circuit structure, comprising: several light emitting units, alignment arrangement;Several power control switches, respectively in every row light emitting unit circuit or every column light emitting unit circuit is set;Several double-path N-channel field effect transistor, with the light emitting unit one-to-one corresponding connection;In the utility model, the switching characteristic of circuit conduction direction of double-path N-channel field effect transistor is utilized, the current conduction direction of double-path N-channel field effect transistor is switched to realize corresponding light emitting unit and the linear light source of being in row / column communication, to form the row / column stripe light source required for being suitable for phase deflection, reduce stripe light period, to realize the phase deflection detection demand of smaller defect greater scene, also through the circuit connection cooperation of double-path N-channel field effect transistor and light emitting unit, reduce the working current of system, reduce power loss.

Description

Technical Field

[0001] This utility model belongs to the field of optical measurement, and in particular relates to a circuit, a light source, a phase deflection detection device, and an electronic device. Background Technology

[0002] Phase deflection is commonly used to detect shallow defects or minor imperfections on glossy surfaces. A typical system consists of a display screen, camera, lens, and computer (or other information processing system). The display screen shows computer-generated structured light stripes, and the camera captures images of the stripes reflected from the target surface. The degree of deformation of the stripes is used to calculate the surface defects.

[0003] Industrial production demands higher detection speeds. Line scan cameras suitable for defect detection production lines can easily achieve line frequencies of 10 kHz. Mainstream LCD displays cannot provide refresh rates at the same speed, and their brightness is not suitable for high-speed sample imaging applications. Therefore, the industry typically uses LED-based phase-deflection light sources. According to the principle of phase deflection, illuminating a sample with the same defect using a light source with a smaller fringe period width allows for a larger phase change to be received at the camera, thus highlighting the defect. Therefore, light sources with smaller fringe periods are suitable for a wider range of defect detection scenarios.

[0004] Phase-deflection light sources require a high-density array of LEDs. During detection, the light source first illuminates several adjacent rows of LEDs and then begins to illuminate them in a rolling motion, either upwards or downwards. After one cycle of row-oriented LEDs, the light source illuminates several adjacent columns of LEDs and then begins to illuminate them in a rolling motion, either to the left or right. After one cycle of column-oriented LEDs, one illumination cycle is completed. This process places certain requirements on the array's density, and a higher LED density results in better detection performance.

[0005] In existing technologies, the fringe period of phase-deflected light sources is too large, and dark areas easily form between adjacent rows of LEDs, resulting in uneven fringes. This necessitates the use of a diffuser plate for light homogenization, and the scattering of the light source leads to low image contrast, making it difficult to detect minute defects and failing to meet the high-precision industrial requirements. High-density LED solutions have high operating current and high losses; while low-density solutions have poor detection performance.

[0006] Patent CN206833894U proposes an LED display driving structure that uses row and column driving arrays, but it is only suitable for low-current LED beads. If the current of a single LED bead is 0.1A, the current reaches 43.2A when the 12×36 array is fully lit, resulting in severe losses.

[0007] Current market solutions separate row and column LEDs and increase voltage and reduce current through series connection to reduce losses. However, the large spacing between rows and columns affects the accuracy of phase deflection detection.

[0008] Therefore, in order to solve the above problems, this utility model provides a circuit, a light source, a phase deflection detection device, and an electronic device to reduce the fringe period of the phase deflection light source and reduce system power consumption. Utility Model Content

[0009] The purpose of this invention is to overcome the above-mentioned problems in the existing technology and to provide a circuit, a light source, a phase deflection detection device, and an electronic device.

[0010] To achieve the above-mentioned technical objectives and effects, this utility model is implemented through the following technical solution:

[0011] A circuit comprising:

[0012] Several light-emitting units are aligned and arranged.

[0013] Several power control switches are respectively set in each row of light-emitting unit circuit or each column of light-emitting unit circuit;

[0014] Several dual-channel N-channel field-effect transistors are connected one-to-one with the light-emitting units, and are used to connect the corresponding light-emitting unit to the light-emitting unit circuit in the row and column of the light-emitting unit respectively through the two current directions of the dual-channel N-channel field-effect transistors.

[0015] At least one controller, connected to the dual-channel N-channel field-effect transistor and the power control switch, is used to control the entire row or column of the aligned light-emitting units to light up simultaneously, so that the lighting rules of the light-emitting units meet the phase deflection detection requirements.

[0016] Furthermore, the light-emitting unit is one of LED beads, laser diodes, organic light-emitting diodes, electroluminescent materials, quantum dot electroluminescent devices, or cold negative electrode fluorescent lamps.

[0017] Furthermore, the circuit also includes a voltage input terminal, which includes:

[0018] Several rows of voltage input terminals are located at the beginning of several rows of light-emitting unit circuits, and are used to input voltage to the corresponding row of light-emitting units through the power supply;

[0019] Several voltage input terminals are located at the starting points of several columns of light-emitting unit circuits, and are used to input voltage to the corresponding column of light-emitting units through the power supply.

[0020] Furthermore, the power control switch includes:

[0021] The first PMOS is located at the start of the horizontal light-emitting unit circuit and is used to control the horizontal voltage input.

[0022] The second PMOS is located at the start of the column light-emitting unit circuit and is used to control the column voltage input;

[0023] The first NMOS is located at the end of the horizontal light-emitting unit circuit and is used to control the horizontal voltage output.

[0024] The second NMOS is located at the end of the column light-emitting unit circuit and is used to control the column voltage output.

[0025] Furthermore, the dual-channel N-channel field-effect transistor includes:

[0026] The light-emitting unit at any non-edge position is connected to the negative terminal of the adjacent light-emitting unit near the voltage input terminal in the row and the adjacent light-emitting unit near the voltage input terminal in the column through the two drains of a dual-channel N-channel field-effect transistor. At least one drain of the dual-channel N-channel field-effect transistor at the beginning of the row or column light-emitting unit circuit is used to connect to the voltage input terminal, and the negative terminal of the light-emitting unit at the end of the row or column light-emitting unit circuit is grounded.

[0027] Furthermore, the controller includes:

[0028] At least one FPGA chip, whose pins are connected to the gates of a dual N-channel field-effect transistor and a power control switch, is used to control the on / off timing and duty cycle of the light-emitting unit via a programmable PWM signal.

[0029] A light source, comprising:

[0030] PCB board, used to mount the circuits as described above;

[0031] The controller is used to sequentially illuminate a linear light source in a row with a preset period according to a preset phase shift, and then sequentially illuminate a linear light source in a column with the same period according to the same phase shift.

[0032] The two drains of the dual-channel N-channel field-effect transistor are connected to the row light-emitting unit circuit and the column light-emitting unit circuit respectively, so that any row light-emitting unit circuit and any column light-emitting unit circuit share the light-emitting unit at the intersection point.

[0033] Furthermore,

[0034] The light-emitting unit and the dual N-channel field-effect transistor in the circuit are replaced by a dual-core LED, wherein the dual-core LED comprises:

[0035] Two light-emitting chips share a substrate and packaging space, and are respectively connected to the row light-emitting unit circuit and the column light-emitting unit circuit.

[0036] A phase deflection detection device, comprising:

[0037] The light source described above is used to emit periodic row and column stripe light sources that light up sequentially according to a preset phase shift;

[0038] A linear scan camera, with pixel rows perpendicular to the direction of movement of the object under test, is used to periodically acquire images of the object under test illuminated by row stripe light sources, and then periodically acquire images of the object under test illuminated by column stripe light sources.

[0039] The processor is used to acquire and process image data of the object under test for phase deflection detection;

[0040] During image acquisition, the linear scan camera and the object under test maintain relative motion, and the image acquisition cycle of the linear scan camera is synchronized with the phase shift cycle of the light source.

[0041] An electronic device includes the phase deflection detection device as described above.

[0042] The beneficial effects of this utility model are:

[0043] (1) In this utility model, by switching the circuit conduction direction of the dual-channel N-channel field-effect transistor, and in conjunction with the requirement for the use of small-period row and column stripe light in phase deflection, the corresponding light-emitting unit is connected to the linear light source in the row / column by switching the current conduction direction of the dual-channel N-channel field-effect transistor, so as to form a row / column stripe light source suitable for phase deflection, and make the light-emitting units arranged in a denser manner, reducing the stripe light period, thereby realizing the phase deflection detection requirements of smaller defects and larger scenes, improving the phase deflection detection accuracy, and ensuring that the row and column stripe light spacing is always the same, so as to optimize the calculation process of the subsequent phase deflection algorithm. Furthermore, by cooperating with the circuit connection between the dual-channel N-channel field-effect transistor and the light-emitting unit, the series connection of all light-emitting units in the row / column linear light source is realized, so as to reduce the operating current of the system and reduce power loss by increasing the voltage.

[0044] (2) In this utility model, a dual-core LED is used as the light source to form a row / column linear light source. The two light-emitting chips in the dual-core LED are independently controlled and connected in series to form the corresponding row / column linear light source. This overcomes the limitation of the spacing of the LED beads as light sources in the prior art. It not only reduces the light period of the formed row / column stripes, but also meets the phase deflection detection requirements of smaller defects and larger scenes, and improves the phase deflection detection accuracy. At the same time, the current loop formed in series can reduce the operating current of the system and reduce power loss by increasing the voltage.

[0045] (3) In this utility model, by controlling the phase deflection light source to sequentially illuminate the row / column stripe light with a preset phase, the row / column stripe light is ensured to move periodically in a preset direction, which meets the illumination requirements of different phase deflection detection scenarios, improves the adaptability of the phase deflection light source, and the periodic change law of the stripe light source is to periodically change the illumination position of the row linear light source with a set direction and phase shift, so as to move the light source display position of the row linear light source, and then periodically change the illumination position of the column linear light source with a set direction and phase shift, so as to move the light source display position of the column linear light source, so as to meet the defect changes in all directions of the surface of the object to be tested and improve the phase deflection detection range.

[0046] (4) In this utility model, based on the hardware parallelism, customizable architecture and underlying hardware optimization characteristics of FPGA, the high-speed strobe of the light source in phase deflection detection is realized by using FPGA to meet the high-speed phase deflection detection requirements, and the number of pins in the light source circuit structure is reduced by increasing the number of FPGAs, thereby reducing hardware resources. Attached Figure Description

[0047] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0048] Figure 1 This is a schematic diagram of the conventional arrangement of light-emitting units in existing technology;

[0049] Figure 2 This is a schematic diagram of the light source circuit connection structure in this utility model;

[0050] Figure 3 This is a schematic diagram showing the connection between the light-emitting unit and the dual-channel N-channel field-effect transistor to form a light-emitting component in this utility model;

[0051] Figure 4 This is a flowchart showing the switching of the on / off working state of the light-emitting unit in this utility model;

[0052] Figure 5 This is a system block diagram of the FPGA controlling the on / off state of the light-emitting unit in this utility model;

[0053] Figure 6 This is a schematic diagram of the periodic change of the stripe phase shift in this utility model;

[0054] Figure 7 This is a schematic diagram of the phase deflection detection device in this utility model. Detailed Implementation

[0055] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0056] In phase deflection testing, since each fringe pattern can only characterize the phase abrupt change of the sample in the fringe phase shift direction, in order to detect defect changes in all directions, the light source needs to display both row and column fringes simultaneously. Therefore, the industry's conventional LED bead arrangement is as follows: Figure 1 As shown, the blank areas represent non-LED installation locations, primarily limited by the LED circuit connections. When row-direction stripes are needed, the row LEDs light up row by row at a certain period, while all column LEDs remain off. Conversely, when column-direction stripes are needed, the column LEDs light up column by column at a certain period, while all row LEDs remain off. Assuming N LEDs are connected in series to form a basic unit, the number of LEDs in each row and column is a positive integer multiple of N. In conventional LED LED arrangement, the minimum center-to-center spacing between LEDs in each row and column is twice the LED's side length. In conventional phase-deflection light source LED arrangement, the theoretically smallest achievable stripe period is one column LED lit and one column LED off (this example only applies to column-direction stripes; the principle is the same for row-direction stripes). The center-to-center distance between two adjacent bright stripes is four times the LED's side length. Assuming the side length of the LED is A, the minimum spatial period of stripes that can be displayed by a conventional phase-deflection light source is 4A.

[0057] To reduce the spatial period of the stripes that a variable stripe light source can display, the spacing between the LEDs should essentially be reduced when the minimum period bright stripe is visible, i.e., the LED density should be increased. Conventional LED arrangement methods in the industry have low density, with a gap equal in size to the LED area next to each LED, where the stripe light consists of parallel black and white stripes.

[0058] To solve the above problems, such as Figures 2-3 As shown, this utility model first provides a circuit, including:

[0059] Several light-emitting units are aligned and arranged.

[0060] Several power control switches are respectively set in each row of light-emitting unit circuit or each column of light-emitting unit circuit;

[0061] Several dual-channel N-channel field-effect transistors are connected one-to-one with the light-emitting units, and are used to connect the corresponding light-emitting unit to the light-emitting unit circuit in the row and column of the light-emitting unit respectively through the two current directions of the dual-channel N-channel field-effect transistors.

[0062] At least one controller, connected to the dual-channel N-channel field-effect transistor and the power control switch, is used to control the entire row or column of the aligned light-emitting units to light up simultaneously, so that the lighting rules of the light-emitting units meet the phase deflection detection requirements.

[0063] In this embodiment, in the aligned light-emitting units, all light-emitting units in any row / column direction are lit simultaneously to form a row / column linear light source for phase deflection detection;

[0064] In this embodiment, the row linear light source is located in the row light-emitting unit circuit, and the column linear light source is located in the column light-emitting unit circuit. The two current directions of the dual-channel N-channel field-effect transistor include the current direction of the row linear light source where the corresponding light-emitting unit is located and the current direction of the column linear light source where it is located. By controlling the dual-channel N-channel field-effect transistor to select one of the current directions, the corresponding light-emitting units can form a row light-emitting unit circuit or a column light-emitting unit circuit, so that the light-emitting unit can be used for the light emission of the row linear light source or the column linear light source.

[0065] In this embodiment, all light-emitting units in the row / column direction are lit simultaneously to form a row / column linear light source. The number of rows and columns of the row / column linear light source to be lit is selected based on the preset row / column linear light source period, thereby forming the row / column stripe light required for phase deflection detection. Several light-emitting units are aligned to ensure that the spacing or period of the formed stripe light is the same. In order to achieve better phase deflection detection effect, the spacing between the row stripe light and the spacing between the column stripe light are the same to facilitate the subsequent phase deflection algorithm calculation.

[0066] In this embodiment, the dual-channel N-channel field-effect transistor includes two NMOS transistors. The sources of the two NMOS transistors are internally connected and share the same pin. The drain and gate are independent to form a bidirectional switch, thereby controlling the light-emitting unit to connect with the linear light source in the row / column.

[0067] In this embodiment, the dual-channel N-channel field-effect transistors correspond one-to-one with the light-emitting units and are interconnected. The source of the dual-channel N-channel field-effect transistor is connected to the positive terminal of the corresponding light-emitting unit to form an integrated light-emitting component. The conduction direction of the dual-channel N-channel field-effect transistor is controlled by the two gates and the drain of the dual-channel N-channel field-effect transistor to control the connection between the light-emitting unit and the linear light source in the row / column. That is, the light-emitting unit can be used as a component of both the row and column linear light sources.

[0068] Among them, the drain of the dual N-channel field-effect transistor located at the beginning of the current direction on the row / column linear light source is used to connect to the input terminal of the row / column current, the negative terminal of the light-emitting unit located at the end of the current direction on the row / column linear light source is used to connect to the ground terminal of the row / column current, and the drain of the dual N-channel field-effect transistor located at the beginning of the current direction on the non-row / column linear light source is used to connect to the negative terminal of the adjacent light-emitting unit in the non-current direction.

[0069] In this embodiment, any light-emitting unit at a non-edge position is connected to the negative terminal of the adjacent light-emitting unit near the voltage input terminal in the row and the adjacent light-emitting unit near the voltage input terminal in the column through the two drains of a dual-channel N-channel field-effect transistor. At least one drain of the dual-channel N-channel field-effect transistor at the beginning of the row or column light-emitting unit circuit is used to connect to the voltage input terminal, and the negative terminal of the light-emitting unit at the end of the row or column light-emitting unit circuit is grounded.

[0070] In some embodiments, the circuit further includes a voltage input terminal, which includes:

[0071] Several rows of voltage input terminals are located at the beginning of several rows of light-emitting unit circuits, and are used to input voltage to the corresponding row of light-emitting units through the power supply;

[0072] Several voltage input terminals are located at the starting points of several columns of light-emitting unit circuits, and are used to input voltage to the corresponding column of light-emitting units through the power supply.

[0073] In this embodiment, the voltage input terminal is also used as the input terminal for row / column current to provide the driving current for the corresponding row / column linear light source current loop. Furthermore, under the control of the dual-channel N-channel field-effect transistor, the light-emitting unit can be located in the circuit of the row current loop or in the circuit of the column current loop, so as to realize the control of the light-emitting unit to connect with the linear light source in the row / column.

[0074] In this embodiment, the dual N-channel field-effect transistor located at the beginning of the current direction on the row / column linear light source represents the first dual N-channel field-effect transistor in the current loop of the row / column linear light source. Since it is located at the beginning of the current loop, one of its drains needs to be connected to the power supply terminal to provide power, and the other drain is connected to the light-emitting unit in the current direction to form a current loop. The two drains of the dual N-channel field-effect transistor, which serves as both the beginning of the current direction of the row linear light source and the beginning of the current direction of the column linear light source, are respectively connected to the row voltage input terminal and the column voltage input terminal. Furthermore, the dual N-channel field-effect transistor at the beginning of the current direction of any row / column linear light source is individually connected to the corresponding row / column voltage input terminal to form an independently controlled current loop.

[0075] In this embodiment, the light-emitting unit located at the end of the current direction of the row / column linear light source represents the tail light-emitting unit of the current loop of the row / column linear light source. Since it is located at the end of the current loop, it needs to be connected to the ground terminal to realize a complete current loop. The negative terminal of the light-emitting unit that serves as both the end of the current direction of the row and column linear light sources is simultaneously connected to the ground terminal of the row current and the ground terminal of the column current. Furthermore, the light-emitting unit at the end of the current direction of any row / column linear light source is individually connected to the ground terminal of the corresponding row / column current to provide the reference voltage of the dual-channel N-channel field-effect transistor to form an independently controlled current loop.

[0076] In this embodiment, the drain of the dual N-channel field-effect transistor, which is not located at the starting end of the current direction on the row / column linear light source, is used to connect to the negative terminal of the adjacent light-emitting unit in the opposite direction of the current direction, so that the two adjacent light-emitting units are connected, and the corresponding light-emitting unit is controlled by the dual N-channel field-effect transistor to be in the same current loop as the adjacent light-emitting unit in the row direction, or in the same current loop as the adjacent light-emitting unit in the column direction.

[0077] In this embodiment, the light-emitting unit is connected to the linear light source in the row / column based on the dual-channel N-channel field-effect transistor, so as to realize the series connection of all light-emitting units on the corresponding row / column linear light source. By increasing the voltage, the operating current of the system can be reduced and the power loss can be reduced. Compared with the prior art where the light-emitting units form striped light with the same arrangement spacing, and each light-emitting unit needs to be provided with an independent driving current, the current loss required in this solution is smaller.

[0078] In this invention, by switching the circuit conduction direction of the dual-channel N-channel field-effect transistors (FETs) in conjunction with the requirement for small-period row and column stripe light in phase deflection, the corresponding light-emitting unit is connected to the linear light source in its row / column by switching the current conduction direction of the dual-channel N-channel FETs. This forms a row / column stripe light source suitable for phase deflection, and allows the light-emitting units to be arranged more densely, reducing the stripe light period. This enables phase deflection detection of smaller defects in larger scenes, improves phase deflection detection accuracy, and ensures that the row and column stripe light spacing remains the same, thus optimizing the calculation process of the subsequent phase deflection algorithm. Furthermore, by coordinating the circuit connection between the dual-channel N-channel FETs and the light-emitting units, all light-emitting units in the row / column linear light source are connected in series, thereby reducing the system's operating current and power loss by increasing the voltage.

[0079] In some embodiments, the light-emitting unit is one of LED beads, laser diodes, organic light-emitting diodes, electroluminescent materials, quantum dot electroluminescent devices, or cold negative electrode fluorescent lamps.

[0080] In this embodiment, the light-emitting units need to be able to connect to dual-channel N-channel field-effect transistors and support series-parallel control to conform to the above circuit structure connection. In addition, the light-emitting units need to use the same light-emitting body to keep the light output of each light-emitting unit consistent so that the formed striped light has good uniformity.

[0081] In some implementations, to achieve independent control of row / column linear light sources and current loop switching, the power control switch includes:

[0082] The first PMOS is located at the start of the horizontal light-emitting unit circuit and is used to control the horizontal voltage input.

[0083] The second PMOS is located at the start of the column light-emitting unit circuit and is used to control the column voltage input;

[0084] The first NMOS is located at the end of the horizontal light-emitting unit circuit and is used to control the horizontal voltage output.

[0085] The second NMOS is located at the end of the column light-emitting unit circuit and is used to control the column voltage output.

[0086] In this embodiment, the first PMOS is located between the input terminal of the horizontal current and the dual N-channel field-effect transistor at the starting terminal of the horizontal linear light source current direction, and is used to control the input of the horizontal current.

[0087] The second PMOS is located between the column current input terminal and the dual N-channel field-effect transistor at the starting terminal of the column linear light source current direction, and is used to control the input of the column current.

[0088] The first NMOS is located between the ground terminal of the row current and the light-emitting unit at the end of the column linear light source current direction, and is used to control the output of the row current.

[0089] The second NMOS is located between the ground terminal of the column current and the light-emitting unit at the end of the column linear light source current direction, and is used to control the output of the column current.

[0090] In this embodiment, a first PMOS is provided at the starting end of any row of linear light sources. The source of the first PMOS is connected to the row voltage input terminal, and the drain of the first PMOS is connected to the drain of the dual N-channel field-effect transistor at the starting end of the current direction of the corresponding row of linear light sources, so as to control the corresponding row voltage input terminal to supply power to the current loop of the linear light source in that row. Correspondingly, a second PMOS is provided at the starting end of any column of linear light sources. The source of the second PMOS is connected to the column voltage input terminal, and the drain of the second PMOS is connected to the drain of the dual N-channel field-effect transistor at the starting end of the current direction of the corresponding column of linear light sources, so as to control the corresponding column voltage input terminal to supply power to the current loop of the linear light source in that column.

[0091] In this embodiment, a first NMOS is provided at the end of each row of linear light sources. The source of the first NMOS is connected to the ground terminal of the row current, and the drain of the first NMOS is connected to the negative terminal of the light-emitting unit at the end of the row linear light source current direction, so as to provide a reference voltage for all dual-channel N-channel field-effect transistors in the corresponding row linear light source to conduct to the current loop of the row linear light source. Correspondingly, a second NMOS is provided at the end of each column of linear light sources. The source of the second NMOS is connected to the ground terminal of the column current, and the drain of the second NMOS is connected to the negative terminal of the light-emitting unit at the end of the column linear light source current direction, so as to provide a reference voltage for all dual-channel N-channel field-effect transistors in the corresponding column linear light source to conduct to the current loop of the column linear light source.

[0092] To ensure that the phase-deflection light source can achieve high-frequency stripe light switching, in some embodiments, the light source further includes:

[0093] At least one FPGA chip, whose pins are directly connected to the gate of a dual N-channel field-effect transistor or the positive / negative terminal of a light-emitting unit, is used to control the on / off timing and duty cycle of a row / column linear light source through a programmable PWM signal.

[0094] In this embodiment, based on the hardware parallelism, customizable architecture, and underlying hardware optimization characteristics of FPGA, the high-speed strobe of the light source in phase deflection detection is implemented by using FPGA to meet the high-speed phase deflection detection requirements. Furthermore, by increasing the number of FPGAs, the number of pins in the light source circuit structure is reduced, thereby reducing hardware resources.

[0095] Secondly, such as Figures 2-5 As shown, this utility model also provides a light source, including:

[0096] PCB board, used to mount the circuits as described above;

[0097] The controller is used to sequentially illuminate a linear light source in a row with a preset period according to a preset phase shift, and then sequentially illuminate a linear light source in a column with the same period according to the same phase shift.

[0098] The two drains of the dual-channel N-channel field-effect transistor are connected to the row light-emitting unit circuit and the column light-emitting unit circuit respectively, so that any row light-emitting unit circuit and any column light-emitting unit circuit share the light-emitting unit at the intersection point.

[0099] In this embodiment, the light source is used for phase deflection detection. In phase deflection detection, the stripe light source display needs to be periodically moved to acquire different phase shift images of the object under test. The specific stripe light source display movement distance, i.e., the phase shift, needs to be set according to the actual situation.

[0100] In this embodiment, the row / column fringe period is determined by a linear light source composed of one or more differently arranged light-emitting units. The actual width of the row / column fringe period also needs to be determined according to actual industrial needs. For linear light sources with the same spacing, the more linear light sources that make up the row / column fringe light, the larger the row / column fringe period; the fewer linear light sources that make up the row / column fringe light, the smaller the row / column fringe period.

[0101] In this embodiment, phase shift represents the periodic movement distance of the row / column stripes. In phase deflection detection, it is necessary to control the periodic movement of the stripe light, that is, to illuminate the row / column stripes sequentially in a certain direction in order to obtain different phase shift images of the test object. However, it is necessary to ensure that the periodic movement distance of the row / column stripes is the same, and the periodic change law of the stripe light source is to periodically change the illumination position of the row linear light source with a set direction and phase shift to move the light source display position of the row linear light source, and then periodically change the illumination position of the column linear light source with a set direction and phase shift to move the light source display position of the column linear light source, so as to meet the defect changes in all directions of the test object surface and improve the phase deflection detection range.

[0102] In this invention, the phase deflection light source is controlled to sequentially illuminate the row / column stripe light at a preset phase, thereby ensuring that the row / column stripe light moves periodically in a preset direction, meeting the illumination requirements of different phase deflection detection scenarios, and improving the adaptability of the phase deflection light source.

[0103] In this embodiment, the method of illuminating the light source to form row / column stripes includes:

[0104] The first PMOS and the first NMOS are closed, and the second PMOS and the second NMOS are open. The dual N-channel field-effect transistor controls the corresponding light-emitting unit to connect with the linear light source in the row, so as to control the corresponding linear light source to be lit.

[0105] The first PMOS is disconnected from the first NMOS, and the second PMOS is closed from the second NMOS. The dual-channel N-channel field-effect transistor controls the corresponding light-emitting unit to connect with the linear light source in the column, so as to control the corresponding column of linear light sources to be lit.

[0106] In this embodiment, when the row linear light source needs to be lit, the first PMOS and the first NMOS are kept closed simultaneously, and the second PMOS and the second NMOS are kept open simultaneously. The corresponding gate of the dual N-channel field-effect transistor controls the light-emitting unit to connect with the corresponding row linear light source, so as to form a current loop for the row linear light source. This completes the simultaneous lighting of all light-emitting units on the corresponding row linear light source, forming row stripe light. Similarly, when the column linear light source needs to be lit, the second PMOS and the second NMOS are kept closed simultaneously, and the first PMOS and the first NMOS are kept open simultaneously. The corresponding gate of the dual N-channel field-effect transistor controls the light-emitting unit to connect with the corresponding column linear light source, so as to form a current loop for the column linear light source. This completes the simultaneous lighting of all light-emitting units on the corresponding column linear light source, forming column stripe light.

[0107] In some implementations, the method of realizing that any row of linear light sources and any column of linear light sources share the same light-emitting unit at the intersection point can also be:

[0108] The light-emitting unit and the dual N-channel field-effect transistor in the circuit are replaced by a dual-core LED, wherein the dual-core LED comprises:

[0109] Two light-emitting chips share a substrate and packaging space, and are respectively connected to the row light-emitting unit circuit and the column light-emitting unit circuit.

[0110] In this embodiment, the two light-emitting chips share a substrate and packaging space, and are respectively connected to the linear light source in the row and the linear light source in the column.

[0111] In this embodiment, a scheme is adopted in which a dual-core LED replaces the light-emitting unit and a dual-channel N-channel field-effect transistor switches the current conduction direction. One of the two light-emitting chips is used as the component unit of the row linear light source and is connected in series to form a row current loop. The other light-emitting chip is used as the component unit of the column linear light source and is connected in series to form a column current loop. By independently controlling the two light-emitting chips as the component units of the row linear light source and the column linear light source respectively, the row / column linear light sources can share the same dual-core LED to reduce the light period of the formed row / column stripes.

[0112] It is important to note that when the two light-emitting chips in a dual-core LED are used as corresponding row / column linear light sources, it is necessary to select light-emitting chips on the same side or at the same position as the constituent units of the corresponding row / column linear light source, so that all light-emitting chips in any row / column linear light source are on the same straight line, thus ensuring the linear collimation of the row / column stripe light.

[0113] In this embodiment, the method of illuminating the light source to form row / column stripes includes:

[0114] The first PMOS and the first NMOS are closed to control the corresponding row of linear light sources to light up;

[0115] The second PMOS and the second NMOS are closed to control the corresponding column of linear light sources to light up.

[0116] In this embodiment, since the constituent units of the row / column linear light source are composed of different light-emitting chips in the dual-core LED, the lighting of the row / column linear light source does not interfere with each other. When the row linear light source needs to be lit, the first PMOS and the first NMOS are kept closed at the same time to form a current loop for the row linear light source, so that all the light-emitting chips on the corresponding row linear light source are lit at the same time, forming row stripe light. Similarly, when the column linear light source needs to be lit, the second PMOS and the second NMOS are kept closed at the same time to form a current loop for the column linear light source, so that all the light-emitting units on the corresponding column linear light source are lit at the same time, forming column stripe light.

[0117] In this invention, dual-core LEDs are used as the light-emitting elements to form the row / column linear light source. The two light-emitting chips in the dual-core LEDs are independently controlled and connected in series to form the corresponding row / column linear light source. This overcomes the limitations of the existing technology in which LED beads are arranged with a certain spacing as light-emitting elements. It not only reduces the light period of the formed row / column stripes, but also meets the phase deflection detection requirements of smaller defects and larger scenes, and improves the phase deflection detection accuracy. At the same time, the current loop formed in series can reduce the system's operating current and reduce power loss by increasing the voltage.

[0118] In addition, such as Figures 6-7 As shown, this utility model also provides a phase deflection detection device, comprising:

[0119] The light source described above is used to emit a periodic row-column linear light source that lights up sequentially according to a preset phase shift;

[0120] A linear scan camera, with pixel rows perpendicular to the direction of movement of the object under test, is used to periodically acquire images of the object under test illuminated by a row of linear light sources, and then periodically acquire images of the object under test illuminated by a column of linear light sources.

[0121] The processor is used to acquire and process image data of the object under test for phase deflection detection;

[0122] During image acquisition, the linear scan camera and the object under test maintain relative motion, and the image acquisition cycle of the linear scan camera is synchronized with the phase shift cycle of the light source.

[0123] In this embodiment, during phase deflection detection, several rows / columns of linear light sources are simultaneously illuminated to form rows / columns of striped light. The striped light period is controlled according to actual detection needs, and periodic phase shift is maintained. During phase shift, the striped light period remains unchanged. Linear light sources at different positions are illuminated according to a certain phase shift direction to control the striped light movement and achieve phase shift of the light source display position. Figure 6As shown, this is a schematic diagram of the periodic phase shift of the light source. During image acquisition, the line scan camera first acquires an image of the object under test illuminated by horizontal stripe light. The image acquisition period of the line scan camera is synchronized with the phase shift period. Then, it acquires an image of the object under test illuminated by vertical stripe light. This is used as a complete light source change cycle for the loop. During the loop, the object under test moves on the conveyor so that the line scan camera and the object under test always maintain relative motion until a complete image of the surface of the object under test is acquired. The acquired image data is obtained by the processor for detection based on phase deflection.

[0124] The conveying device can be a conveyor belt or other stepping device to move the object to be tested.

[0125] Finally, this invention provides an electronic device, including the phase deflection detection device as described above. Example 1

[0126] In this embodiment, the circuit structure is as follows: Figure 2 As shown in the figure, VCC1 represents the column voltage input terminal, whose voltage depends on the operating voltage U of a single LED and the number of LEDs n in each column, VCC1=U*n; VCC2 represents the row voltage input terminal, whose voltage depends on the operating voltage U of a single LED and the number of LEDs m in each row, VCC2=U*m; LED1-LED12 represent aligned light-emitting units, in this embodiment the light-emitting units are LEDs, N1-N12 represent dual-channel N-channel field-effect transistors, G1 represents the gate of the dual-channel N-channel field-effect transistor that controls the connection between the LED and the linear light source in the row, G2 represents the gate of the dual-channel N-channel field-effect transistor that controls the connection between the LED and the linear light source in the column, P1-P4 represent the second PMOS, P5-P7 represent the first PMOS, N13-N16 represent the second NMOS, and N17-N19 represent the first NMOS.

[0127] In this embodiment, the specific lighting / off logic sequence of the row / column linear light source is as follows:

[0128] S1. In the initial state, all LEDs are off. At this time, the first PMOS and the second PMOS: P1-P4, P5-P7 are all disconnected.

[0129] S2. When the light-emitting unit array needs to be lit in row mode to form a row linear light source: First, close to turn on the first NMOS: N17-N19, providing a reference voltage for the subsequent conduction of the dual N-channel field-effect transistors; then close to turn on the G1 channel of the dual N-channel field-effect transistors: N4, N8, and N12, and turn off the G2 channel; then, in order from right to left, perform the same process on the dual N-channel field-effect transistors in the column direction; finally, turn on the first PMOS: P5, P6, or P7 by closing to light up the corresponding LED in the row linear light source;

[0130] S3. When the LED array needs to switch from row-lit mode to off mode: First, disconnect the first single PMOS: P5, P6 and P7; then disconnect the G1 channel of the dual N-channel field-effect transistors: N1, N5 and N9; then, perform the same process on the dual N-channel field-effect transistors in the column direction in order from left to right; finally, disconnect the first NMOS: N17, N18 and N19.

[0131] S4. When the light-emitting unit array needs to be lit in column mode to form a column linear light source: First, close to turn on the second NMOS: N13-N16, providing a reference voltage for the subsequent conduction of the dual N-channel field-effect transistors; then close to turn on the G2 channel of the dual N-channel field-effect transistors: N9, N10, N11 and N12, and turn off the G1 channel; then, in order from bottom to top, perform the same process on the dual N-channel field-effect transistors in the row direction; finally, turn on the second PMOS: P1, P2, P3 or P4 by closing to light up the corresponding LEDs in the column linear light source;

[0132] S5. When the LED array needs to switch from column lighting mode to off mode: First, disconnect the single second PMOS: P1, P2, P3 and P4; then disconnect the G2 channel of the dual N-channel field-effect transistors: N1, N2, N3 and N4; then, perform the same process on the dual N-channel field-effect transistors in the row direction in the order from top to bottom; finally, disconnect the second NMOS: N13, N14, N15 and N16.

[0133] The flowchart for switching system operating states is as follows: Figure 4 As shown. The system needs to return to the off state before it can switch to row lighting mode or column lighting mode.

[0134] In this embodiment, although each dual-channel N-channel MOSFET requires two control signals to control channels G1 and G2 respectively, in row-lit or column-lit modes, channels G1 and G2 of each dual-channel N-channel MOSFET will not be turned on simultaneously; only one channel will be turned on. Therefore, the control signal of channel G1 of the same dual-channel N-channel MOSFET can be connected to channel G2 through an inverter, thus saving half of the control pins. Example 2

[0135] In this embodiment, the system block diagram for controlling the LEDs to turn on and off via FPGA is as follows: Figure 5As shown in the diagram, the PC is the host computer, used to send instructions to adjust parameters such as the stripe shape, switching frequency, and brightness of the light source; the MCU is used for instruction parsing, receiving and parsing the instructions sent by the host computer through the RS232 interface, converting them into specific parameters, and sending them to each FPGA through the SPI interface; FPGA_1 is the master FPGA, used to control the switching of rows or columns to achieve stripe switching, i.e., the first PMOS, the second PMOS, the first NMOS, and the second NMOS: P1-P7 and N13-N19; FPGA_2 and FPGA_3 are slave FPGAs, used to control the row and column direction switching of specific LEDs, where FPGA_2 controls columns 1-18 of LEDs, a total of 216 LEDs, and FPGA_3 controls columns 19-36 of LEDs, a total of 216 LEDs; there are 4 ROW_COL_SYNC signals between each FPGA, used to switch between four states: column on, column off, row on, and row off.

[0136] In this embodiment, the FPGA control logic for lighting up the light-emitting unit specifically includes:

[0137] A1. In row illumination mode: First, FPGA_1 turns on the first NMOS: N17, N18, and N19. After turning them on, it notifies FPGA_2 by pulling up the ROW_COL_SYNC signal. Upon receiving this signal, FPGA_2 turns on the G1 channel of the dual N-channel MOSFETs COL1-COL18 in right-to-left order and turns off the G2 channel. After completing the operation of COL18, it notifies FPGA_3 by pulling up the ROW_COL_SYNC signal. Upon receiving this signal, FPGA_2 turns on the G1 channel of the dual N-channel MOSFETs COL19-COL36 in right-to-left order and turns off the G2 channel. After completing the operation of COL36, it notifies FPGA_1 by pulling up the ROW_COL_SYNC signal. At this time, FPGA_1 controls the first PMOS: P5, P6, and P7 to project different row stripes.

[0138] A2. Switching from row lighting mode to off mode is the reverse of the lighting operation sequence. At the same time, the FPGAs distinguish the lighting mode by pulling up different ROW_COL_SYNC signals.

[0139] A3. In column illumination mode: First, FPGA_1 turns on the second NMOS: N13, N14, N15, and N16. After turning them on, it will notify FPGA_2 and FPGA3 by pulling up the ROW_COL_SYNC signal. After receiving the signal, FPGA_2 and FPGA3 turn on the G2 channel of the dual N-channel field-effect transistors ROW1-ROW12 in order from bottom to top, and turn off the G1 channel. After completing the operation of ROW12, they will notify FPGA_1 by pulling up the ROW_COL_SYNC signal. At this time, FPGA_1 controls the second PMOS P1, P2, P3, and P4 to project different column stripes.

[0140] A4. Switching from column illumination mode to off mode is the reverse of the illumination operation sequence. At the same time, FPGAs distinguish between illumination modes by pulling up different ROW_COL_SYNC signals.

[0141] In this embodiment, the system can drive a larger-scale LED array by increasing the number of slave FPGAs. Each additional slave FPGA only requires 4 more pins per FPGA to achieve synchronization with other FPGAs, thus providing scalability.

[0142] In the description of this specification, references to terms such as "an embodiment," "example," and "specific example" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0143] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A circuit, characterized in that, include: Several light-emitting units are aligned and arranged. Several power control switches are respectively set in each row of light-emitting unit circuit or each column of light-emitting unit circuit; Several dual-channel N-channel field-effect transistors are connected one-to-one with the light-emitting units, and are used to connect the corresponding light-emitting unit to the light-emitting unit circuit in the row and column of the light-emitting unit respectively through the two current directions of the dual-channel N-channel field-effect transistors. At least one controller, connected to the dual-channel N-channel field-effect transistor and the power control switch, is used to control the entire row or column of the aligned light-emitting units to light up simultaneously, so that the lighting rules of the light-emitting units meet the phase deflection detection requirements.

2. The circuit according to claim 1, characterized in that, The light-emitting unit is one of the following: LED beads, laser diode, organic light-emitting diode, electroluminescent material, quantum dot electroluminescent device, or cold negative electrode fluorescent lamp.

3. A circuit according to any one of claims 1-2, characterized in that, The circuit further includes a voltage input terminal, which includes: Several rows of voltage input terminals are located at the beginning of several rows of light-emitting unit circuits, and are used to input voltage to the corresponding row of light-emitting units through the power supply; Several voltage input terminals are located at the starting points of several columns of light-emitting unit circuits, and are used to input voltage to the corresponding column of light-emitting units through the power supply.

4. The circuit according to claim 3, characterized in that, The power control switch includes: The first PMOS is located at the start of the horizontal light-emitting unit circuit and is used to control the horizontal voltage input. The second PMOS is located at the start of the column light-emitting unit circuit and is used to control the column voltage input; The first NMOS is located at the end of the horizontal light-emitting unit circuit and is used to control the horizontal voltage output. The second NMOS is located at the end of the column light-emitting unit circuit and is used to control the column voltage output.

5. A circuit according to claim 4, characterized in that, The dual-channel N-channel field-effect transistor includes: The light-emitting unit at any non-edge position is connected to the negative terminal of the adjacent light-emitting unit near the voltage input terminal in the row and the adjacent light-emitting unit near the voltage input terminal in the column through the two drains of a dual-channel N-channel field-effect transistor. At least one drain of the dual-channel N-channel field-effect transistor at the beginning of the row or column light-emitting unit circuit is used to connect to the voltage input terminal, and the negative terminal of the light-emitting unit at the end of the row or column light-emitting unit circuit is grounded.

6. A circuit according to any one of claims 1-2, characterized in that, The controller includes: At least one FPGA chip, whose pins are connected to the gates of a dual N-channel field-effect transistor and a power control switch, is used to control the on / off timing and duty cycle of the light-emitting unit via a programmable PWM signal.

7. A light source, characterized in that, include: PCB board for mounting the circuit as described in any one of claims 1-6; The controller is used to sequentially illuminate a linear light source in a row with a preset period according to a preset phase shift, and then sequentially illuminate a linear light source in a column with the same period according to the same phase shift. The two drains of the dual-channel N-channel field-effect transistor are connected to the row light-emitting unit circuit and the column light-emitting unit circuit respectively, so that any row light-emitting unit circuit and any column light-emitting unit circuit share the light-emitting unit at the intersection point.

8. A light source according to claim 7, characterized in that, The light-emitting unit and the dual N-channel field-effect transistor in the circuit are replaced by a dual-core LED, wherein the dual-core LED comprises: Two light-emitting chips share a substrate and packaging space, and are respectively connected to the row light-emitting unit circuit and the column light-emitting unit circuit.

9. A phase deflection detection device, characterized in that, include: The light source as described in any one of claims 7-8 is used to emit a periodic row and column stripe light source that is lit sequentially according to a preset phase shift; A linear scan camera, with pixel rows perpendicular to the direction of movement of the object under test, is used to periodically acquire images of the object under test illuminated by row stripe light sources, and then periodically acquire images of the object under test illuminated by column stripe light sources. The processor is used to acquire and process image data of the object under test for phase deflection detection; During image acquisition, the linear scan camera and the object under test maintain relative motion, and the image acquisition cycle of the linear scan camera is synchronized with the phase shift cycle of the light source.

10. An electronic device, characterized in that, Includes the phase deflection detection device as described in claim 9.

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