Constant temperature control method, device and equipment and laser processing system

Abstract

The invention relates to the technical field of laser equipment, and discloses a constant temperature control method, which comprises the following steps of: segmenting a working area into a plurality of pixel points according to the size of the working area and the minimum resolution of a temperature sensor; controlling a temperature sensor to move and acquiring temperature values of a plurality of pixel points in the current working area; calculating an actual difference value between the temperature value of each pixel point and a preset process temperature value; and outputting a laser light source control signal according to an actual difference value between the temperature value of each pixel point and a preset process temperature value, and adjusting the current output of the laser light source according to the laser light source control signal. A laser light source control signal is output according to the actual difference value between the temperature value of each pixel point and the preset process temperature value, so that the current output of the laser light source is adjusted in time, and a response can be made in time according to the change of the temperature value of the pixel point. The condition that the temperature value of an individual pixel point exceeds or cannot reach the process temperature value in the prior art is avoided, and the yield of the processed object is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of laser equipment technology, and specifically to a constant temperature control method, device, equipment and laser processing system. Background Art

[0002] Micro LED is the next generation display technology. Its chip size is generally 1 to 100μm and its thickness is only 5μm. There are 8.3 million pixels on a single 4K display panel, which means that about 25 million Micro LED chips are needed to meet the single 4K display of Mirco LED. Micro LED chips are too small. The precision of traditional die bonding equipment makes it difficult to improve the effect of die bonding (unless the speed is greatly reduced). The traditional reflow oven method also exacerbates the defects in the production process. It can be seen that the original die bonding technology is no longer applicable, and mass processing technology, such as mass transfer technology and mass welding technology, is required.

[0003] In the prior art, the mass transfer technology and mass welding technology are realized by using a laser light source. A laser processing system with uniform spot energy distribution is used to irradiate the Mirco LED chip (including the response layer material or substrate) before and after the transfer, that is, a constant power mode is adopted to utilize the thermal decomposition between the laser and the material, or the material absorbs the laser energy to react, so as to achieve the purpose of shedding and welding. However, in the mass transfer or mass welding of Micro LED, a stable constant temperature mode is required rather than a constant power mode. The constant power mode will cause high-energy laser to damage Micro LED during the welding process, or low-energy laser will cause poor welding of Micro LED chips; at the same time, because the substrate materials of Micro LED are different, such as PCB, glass, aluminum substrate and ceramic, different materials have different sensitivity to temperature and reflectivity to laser, which will require higher constant temperature. Summary of the invention

[0004] In view of the above problems, the embodiments of the present application provide a constant temperature control method, device, equipment and laser processing system, so that the laser processing system always maintains a constant temperature mode when performing mass processing of Micro LEDs, thereby improving the product yield during the mass processing of Micro LEDs.

[0005] According to one aspect of an embodiment of the present application, a constant temperature control method is provided, which includes: dividing the working area into multiple pixel points according to the size of the working area and the minimum resolution of the temperature sensor; controlling the movement of the temperature sensor and acquiring the temperature values ​​of multiple pixel points in the current working area; calculating the actual difference between the temperature value of each pixel point and the preset process temperature value; outputting a laser light source control signal according to the actual difference between the temperature value of each pixel point and the preset process temperature value, and adjusting the current output of the laser light source according to the laser light source control signal. By redividing the working area into multiple pixel points, the granularity of a single temperature acquisition area becomes smaller, and by controlling the movement of the temperature sensor and acquiring the temperature values ​​of multiple pixel points in the current working area, the actual difference between the temperature value of each pixel point and the preset process temperature value is calculated, and a laser light source control signal is output according to the actual difference between the temperature value of each pixel point and the preset process temperature value. The current output of the laser light source is adjusted according to the laser light source control signal. The laser processing system can respond in time according to changes in the pixel temperature value, thereby avoiding the situation in the prior art where the temperature sensor outputs the average temperature and subjectively ignores that the temperature value of individual pixels exceeds or fails to reach the process temperature value, and further avoids the situation where the processed object in the working area where the pixel point is located is burned or poorly welded, resulting in rework, thereby improving the yield of the processed object.

[0006] In an optional manner, the constant temperature control method further includes the following steps: when the processed object in the current working area is completely processed, controlling the temperature sensor and the laser light source to move to form a next working area, and using the next working area as the current working area. The embodiment of the present application can further improve the working efficiency of the laser processing system by identifying whether the processed object in the current working area has been processed, controlling the movement of the temperature sensor and the laser light source, and processing all the working areas to be processed of the processed object.

[0007] In an optional manner, the constant temperature control method further comprises the following steps: when all the processed objects are processed, the power of the laser light source is controlled to be turned off, and the output of the laser light source is stopped. The embodiment of the present application timely controls the laser light source to be turned off by identifying whether all the processed objects are processed, thereby preventing unnecessary damage to other objects that do not need to be processed.

[0008] In an optional manner, the current working area refers to a working area formed by irradiating a preset light spot formed by an optical shaping module with a laser light source as the light source onto the object to be processed. The embodiment of the present application uses a laser light source as the light source, and optically shapes the light beam output by the laser light source through an optical shaping module to form a line light spot or a point light spot according to actual application needs. The line light spot can process multiple processed objects at one time, thereby improving the processing efficiency of the laser processing system. The optical shaping module can also adjust one or more parameters of the length, width and depth of focus of the line light spot online as needed, so that the light spot output by the laser light source can be flexibly set according to actual processing needs. The point light spot can accurately irradiate the area to be processed. It can also be a multi-point combined light spot formed by DOE (Diffractive Optical Elements).

[0009] In an optional manner, the step of outputting a laser light source control signal according to the actual difference between the temperature value of each pixel and the preset process temperature value, and adjusting the current output of the laser light source according to the laser light source control signal specifically includes: when the actual difference between the temperature value of one of the pixel points and the preset process temperature value exceeds the preset difference, generating a control signal according to the actual difference, converting the control signal into a laser light source control signal, and adjusting the current output of the laser light source according to the laser light source control signal. In the embodiment of the present application, since the current working area is re-divided, the granularity of temperature acquisition becomes smaller, and the laser processing system can respond in time according to the change of the pixel point temperature value, avoiding the situation in the prior art that the temperature sensor outputs the average temperature subjectively ignoring that the temperature value of individual pixels exceeds or fails to reach the process temperature value, further avoiding the situation that the processed object in the working area where the pixel point is located is burned or poorly welded, resulting in rework, thereby improving the yield of the processed object.

[0010] According to one aspect of an embodiment of the present application, a constant temperature control device is provided, and the constant temperature control device includes: a segmentation module, which is used to segment the working area into multiple pixel points according to the size of the working area and the minimum resolution of the temperature sensor; an acquisition module, which is used to control the movement of the temperature sensor and obtain the temperature values ​​of multiple pixel points in the current working area; a calculation module, which is used to calculate the actual difference between the temperature value of each pixel point and the preset process temperature value; an adjustment module, which is used to output a laser light source control signal according to the actual difference between the temperature value of each pixel point and the preset process temperature value, and adjust the current output of the laser light source according to the laser light source control signal; a movement module, which is used to control the movement of the temperature sensor and the laser light source to form a next working area when the processed object in the current working area is completely processed, and use the next working area as the current working area.

[0011] In an alternative manner, the constant temperature control device further includes: a shutdown module, configured to control the laser light source power supply to shut down and stop the output of the laser light source when all the objects to be processed are completely processed.

[0012] According to another aspect of the embodiments of the present application, a constant temperature control device is provided, which includes: a processor, a memory, a communication interface, and a communication bus. The processor, the memory, and the communication interface complete mutual communication through the communication bus; the memory is used to store executable instructions, and the executable instructions cause the processor to execute the operations of the constant temperature control method.

[0013] According to another aspect of the embodiments of the present application, a laser processing system is provided, which includes a temperature acquisition module, the constant temperature control device, a laser light source, and an object to be processed.

[0014] According to another aspect of the embodiments of the present application, a computer-readable storage medium is provided. The storage medium stores executable instructions, and when the executable instructions run on the constant temperature control device, the constant temperature control device is caused to execute the operations of the constant temperature control method.

[0015] In the constant temperature control method, device, equipment, and laser processing system provided by the embodiments of the present application, by re-dividing the working area into multiple pixel points, the granularity of the single temperature acquisition area becomes smaller. By controlling the movement of the temperature sensor and obtaining the temperature values of multiple pixel points within the current working area, calculating the actual difference between the temperature value of each pixel point and the preset process temperature value, outputting a laser light source control signal according to the actual difference between the temperature value of each pixel point and the preset process temperature value, and adjusting the current output of the laser light source according to the laser light source control signal, the laser processing system can respond in a timely manner according to the change of the pixel point temperature value, avoiding the situation in the prior art that the average temperature output by the temperature sensor subjectively ignores the situation that the temperature value of individual pixel points exceeds or fails to reach the process temperature value, and further avoiding the situation of rework caused by burning or poor welding of the object to be processed in the working area where the pixel points are located, improving the yield of the object to be processed. When the constant temperature control method, device, equipment, and laser processing system provided by the embodiments of the present application are applied to the massive processing of MicroLED, the laser processing system can always maintain a constant temperature mode during the massive processing of Micro LED, thereby improving the product yield during the massive processing of Micro LED.

[0016] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0018] Figure 1 A schematic diagram of a constant temperature control method provided in an embodiment of the present application;

[0019] Figure 2 This is a schematic diagram of dividing the working area of ​​the object to be processed in the embodiment of the present application;

[0020] Figure 3 A schematic diagram of the structure of a constant temperature control device provided in an embodiment of the present application;

[0021] Figure 4 A schematic diagram of the structure of a constant temperature control device provided in an embodiment of the present application;

[0022] Figure 5 A schematic diagram of the structure of a laser processing system provided in an embodiment of the present application.

[0023] The reference numerals in the specific implementation manner are as follows:

[0024] 100, working area of ​​the object being processed; 101, current working area; 1010, pixel point;

[0025] 200, constant temperature control device; 210, segmentation module; 220, acquisition module; 230, calculation module; 240, adjustment module; 250, motion module; 260, closing module;

[0026] 300, constant temperature control device; 302, processor; 304, communication interface; 306, memory; 308, communication bus; 310, program;

[0027] 400, laser processing system; 410, temperature acquisition module; 420, laser light source; 430, object to be processed. DETAILED DESCRIPTION

[0028] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0030] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0031] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0032] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0033] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0034] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0035] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0036] The size and mass of Micro LED chips are extremely small. After the chips are transferred, it is very difficult to use traditional reflow ovens for processing, because slight vibrations may cause the chips to shift. At the same time, due to thermal stress, slight warping can also cause the chips to shift. Using lasers for mass welding or mass transfer is the only option.

[0037] At present, it is difficult to control the yield of Micro LED within 100 PPM (Parts Per Million), that is, for a Micro LED display the size of a palm, the number of defective LEDs is about 4 to 5. Micro LED display repair also faces challenges. The repair process of the Micro MED display includes: melting the solder joints of the chip, removing the chip, cleaning the pads, re-applying solder paste, solidifying the new chip, and chip welding. The direct factor affecting the welding quality is temperature. The laser processing system in the prior art uses a homogenized light spot, so the energy of the laser emitted by it is projected onto the working panel is uniform, but the temperature on the working panel is affected by multiple other factors, such as: solder paste, reflectivity of the substrate, etc. Therefore, the temperature is often uneven when a large-area homogenized light spot laser processing system is used for mass processing.

[0038] Based on this, on the one hand, an embodiment of the present application provides a constant temperature control method, so that the laser processing system always maintains a constant temperature mode when performing mass processing on the processed object, thereby improving the product yield during the mass processing of the processed object.

[0039] The embodiment of the present application uses a laser light source to match high-speed closed-loop temperature control to achieve constant temperature control. Traditional high-speed closed-loop temperature control generally adopts the method of averaging the temperature of the working area. In this way, if the range of temperature control is a point, then the test area is also limited to this small point, and it is even possible that the entire processing cannot be carried out normally because this point is too sensitive. If the selected range is a large surface, because the average temperature of the working area is used, then when one or more hot spots in the working area cannot be controlled, the meaning of temperature control is lost, and it is also easy to cause poor welding.

[0040] One of the embodiments of the present application uses a temperature measuring instrument (for example, infrared non-contact temperature measurement. Currently, the theoretical minimum resolution pixel of the target surface is 15um (the actual resolution pixel is 25um)) to move synchronously with the laser light source. During the imaging process, the target surface of the temperature measuring instrument divides the 100*2mm spot working area into multiple pixels of 85*85um to collect and upload the temperature (30 frames / s). The algorithm in the MCU of the high-speed closed-loop temperature control system compares the temperatures of multiple pixels in the 100*2mm spot working area with the upper and lower limits of the process temperature value. When the temperature of a certain pixel exceeds a certain threshold of the limit, the PID (Proportional-Integral-Derivative control) is used to adjust the current output of the laser light source to trigger the system response, thereby avoiding the situation where the average temperature output by the temperature sensor subjectively ignores the temperature of individual pixels (or a small part of the temperature measurement position) exceeding the process limit, which results in the system not needing to respond, and the Micro LED chip is burned and reworked.

[0041] See also Figure 1 , Figure 1 A schematic flow chart of a constant temperature control method provided in an embodiment of the present application is shown.

[0042] In an embodiment of the present application, the constant temperature control method comprises the following steps:

[0043] S1: Divide the working area into a plurality of pixels according to the size of the working area and the minimum resolution of the temperature sensor.

[0044] Specifically, in an embodiment of the present invention, the current working area refers to a working area formed by irradiating a laser light source as a light source and a preset light spot formed by an optical shaping module onto the object to be processed. The embodiment of the present application adopts a laser light source as a light source, and optically shapes the light beam output by the laser light source through an optical shaping module to form a preset light spot according to actual application needs. The preset light spot can be a line light spot or a point light spot. The line light spot can process multiple processed objects at one time, thereby improving the processing efficiency of the laser processing system. The optical shaping module can also adjust one or more parameters of the length, width and focal depth of the line light spot online as needed, so that the light spot output by the laser light source can be flexibly set according to actual processing needs. The point light spot can accurately irradiate the area to be processed. In other embodiments, the laser light source can also form a multi-point combined light spot through DOE. The embodiment of the present invention does not limit the light spot shape output by the laser light source. In one embodiment, the size of the current working area is 100mm*2mm. According to the small resolution of the temperature sensor, for example, the theoretical minimum resolution of the target surface of the temperature sensor is 25um, the current working area is divided into pixels that can be collected by the temperature sensor, for example, 85um*85um. It can be understood that in other embodiments, the current working area can be divided into pixels according to the size of the current working area of ​​the processed object and the processing accuracy requirements of the processed object. The purpose is to re-divide the current working area and reduce the single temperature collection area so that the collected temperature can fully reflect the actual temperature of the current working area, thereby correcting the laser irradiation energy of the current working area according to the actual temperature to achieve a constant temperature working mode.

[0045] S2: Control the movement of the temperature sensor and obtain the temperature values ​​of multiple pixels in the current working area;

[0046] In the embodiment of the present invention, it is understandable that the laser light source needs to move in different areas of the object to be processed according to the characteristics of the object to be processed and the processing requirements, so as to act on different areas of the object to be processed. Therefore, the current working area refers to the processing area on the object to be processed where the current laser light source irradiates. The temperature sensor is controlled to move along the current working area to obtain the temperature values ​​of multiple pixels in the current working area, so as to control the output of the laser light source current according to the actual temperature value of the current processing area of ​​the object to be processed. Specifically, the temperature acquisition rate can be determined according to the control accuracy of the laser processing system. In a specific embodiment, the temperature acquisition rate is 30 frames / s. It is understandable that when all the pixels in the current working area are acquired, step S2 is repeated until the processed object in the current working area is completely processed, and step S5 is executed.

[0047] S3: Calculate the actual difference between the temperature value of each pixel and the preset process temperature value;

[0048] Specifically, when the temperature value of one of the pixels is collected, the difference between the temperature value of the pixel and the preset process temperature value is calculated and recorded. It can be understood that step S3 and step S2 can be executed synchronously. That is, when step S2 collects the temperature of a pixel, step S3 simultaneously calculates and records the difference between the temperature value of the pixel and the preset process temperature value. This execution method allows the system to react quickly to the temperature value of the current working area, and is suitable for occasions where high system sensitivity and accuracy are required. Step S3 and step S2 can also be executed asynchronously. That is, step S2 first collects the temperature values ​​of all pixels in the current working area until the processed object in the current working area is completely processed, and then executes step S3. This execution method is suitable for occasions where low system sensitivity and accuracy are required.

[0049] S4: outputting a laser light source control signal according to the actual difference between the temperature value of each pixel point and the preset process temperature value, and adjusting the current output of the laser light source according to the laser light source control signal;

[0050] Specifically, when the actual difference between the temperature value of one of the pixel points and the preset process temperature value exceeds the preset difference, a control signal is generated according to the actual difference, the control signal is converted into a laser light source control signal, and the current output of the laser light source is adjusted according to the laser light source control signal. Usually, the control signal is a PID control signal. The working area is divided into multiple pixel points, and the laser light source control signal is output according to the difference between the temperature value of each pixel point and the preset process temperature value. Since the current working area is re-divided, the granularity of temperature acquisition becomes smaller, and the laser processing system can respond in time according to the change of the pixel point temperature value, avoiding the situation in the prior art that the temperature sensor outputs the average temperature and subjectively ignores that the temperature value of individual pixel points exceeds or fails to reach the process temperature value, and further avoids the situation that the processed object in the working area where the pixel point is located is burned or poorly welded, resulting in rework, thereby improving the yield of the processed object.

[0051] S5: When the processed object in the current working area is completely processed, the temperature sensor and the laser light source are controlled to move to form a next working area, and the next working area is used as the current working area. Jump to step S2.

[0052] Specifically, when the processed object in the current working area is completely processed, the temperature sensor is controlled to move together with the laser light source to form a next working area, and the next working area is used as the current working area, and the process jumps to step S2.

[0053] Furthermore, the constant temperature control method further comprises the following steps:

[0054] S6: When all the processed objects are processed, the power of the laser light source is controlled to be turned off, and the output of the laser light source is stopped.

[0055] See also Figure 2 , Figure 2 A schematic diagram of dividing the working area of ​​the object to be processed in an embodiment of the present application is shown.

[0056] In the embodiment of the present application, the object to be processed includes a working area 100, the area irradiated by the laser light source is the current working area 101, and the current working area 101 is divided into a plurality of pixel points 1010. In other embodiments, the working area 100 of the object to be processed can also be divided in advance as a whole to determine the pixel points.

[0057] The constant temperature control method provided in the embodiment of the present application, by re-dividing the working area into multiple pixels, the granularity of the single temperature acquisition area becomes smaller, by controlling the movement of the temperature sensor and obtaining the temperature values ​​of multiple pixels in the current working area, calculating the actual difference between the temperature value of each pixel and the preset process temperature value, outputting a laser light source control signal according to the actual difference between the temperature value of each pixel and the preset process temperature value, adjusting the current output of the laser light source according to the laser light source control signal, and the laser processing system can respond in time according to the change of the temperature value of the pixel point, avoiding the situation in the prior art that the temperature sensor outputs the average temperature subjectively ignoring that the temperature value of individual pixels exceeds or fails to reach the process temperature value, further avoiding the situation that the processed object in the working area where the pixel point is located is burned or the welding is poor, resulting in rework, and improving the yield of the processed object. When the constant temperature control method provided in the embodiment of the present application is applied to Micro LED mass processing, it can enable the laser processing system to always maintain a constant temperature mode when processing Micro LEDs in mass, thereby improving the product yield in the process of Micro LED mass processing.

[0058] On the other hand, the present application provides a constant temperature control device for Micro LED mass processing, so that the laser processing system always maintains a constant temperature mode when performing mass processing on Micro LEDs, thereby improving the product yield in the Micro LED mass processing process.

[0059] See also Figure 3 , Figure 3 A schematic diagram of the structure of a constant temperature control device provided in an embodiment of the present application is shown.

[0060] In the embodiment of the present application, the constant temperature control device 200 includes a segmentation module 210 , a collection module 220 , a calculation module 230 , an adjustment module 240 and a motion module 250 .

[0061] A segmentation module 210 is used to segment the working area into multiple pixel points according to the size of the working area and the minimum resolution of the temperature sensor; an acquisition module 220 is used to control the movement of the temperature sensor and obtain the temperature values ​​of multiple pixel points in the current working area; a calculation module 230 is used to calculate the actual difference between the temperature value of each pixel point and the preset process temperature value; an adjustment module 240 is used to output a laser light source control signal according to the actual difference between the temperature value of each pixel point and the preset process temperature value, and adjust the current output of the laser light source according to the laser light source control signal; a movement module 250 is used to control the movement of the temperature sensor and the laser light source to form the next working area when the processed object in the current working area is completely processed, and use the next working area as the current working area.

[0062] In an optional embodiment, the current working area refers to a working area formed by irradiating a preset light spot formed by an optical shaping module with a laser light source as the light source onto the object to be processed. The embodiment of the present application adopts a laser light source as the light source, and optically shapes the light beam output by the laser light source through the optical shaping module to form a preset light spot according to the actual application needs. The preset light spot can be a line light spot or a point light spot. The line light spot can process multiple objects to be processed at one time, thereby improving the processing efficiency of the laser processing system. The optical shaping module can also adjust one or more parameters of the length, width and depth of focus of the line light spot online as needed, so that the light spot output by the laser light source can be flexibly set according to the actual processing needs. The point light spot can accurately irradiate the area to be processed. In other embodiments, the laser light source can also form a multi-point combined light spot through DOE. The embodiment of the present invention does not limit the light spot shape output by the laser light source. In one embodiment, the size of the current working area is 100mm*2mm. According to the small resolution of the temperature sensor, for example, the theoretical minimum resolution of the target surface of the temperature sensor is 25um, the current working area is divided into pixels that can be collected by the temperature sensor, such as 85um*85um. It can be understood that in other embodiments, the segmentation module 210 can divide the pixels of the current working area according to the size of the current working area of ​​the processed object and the processing accuracy requirements of the processed object. The purpose is to re-divide the current working area and reduce the single temperature collection area so that the collected temperature can fully reflect the actual temperature of the current working area, thereby correcting the laser irradiation energy of the current working area according to the actual temperature to achieve a constant temperature working mode.

[0063] In an optional embodiment, since the laser light source needs to move in different areas of the processed object according to the characteristics of the processed object and the processing requirements, so as to act on different areas of the processed object. Therefore, the current working area refers to the processing area on the processed object irradiated by the current laser light source. The acquisition module 220 is used to control the temperature sensor to move along the current working area, and obtain the temperature value of each pixel point in the current working area, so as to control the output of the laser light source current according to the actual temperature value of the current processing area of ​​the processed object. Specifically, the temperature acquisition rate can be determined according to the control accuracy of the laser processing system. In a specific embodiment, the temperature acquisition rate is 30 frames / s. When the acquisition module 220 completes the acquisition of all the pixels in the current working area, the acquisition module 220 controls the temperature sensor to move along the current working area again, and obtains the temperature value of each pixel point in the current working area, until the processed object in the current working area is completely processed, and the motion module 250 controls the temperature sensor and the laser light source to move to form the next working area, and the next working area is used as the current working area.

[0064] In an optional embodiment, the calculation module 230 is specifically used to calculate and record the difference between the temperature value of one pixel and the preset process temperature value when the temperature value of one pixel is collected. It can be understood that the calculation module 230 and the acquisition module 220 can be integrated into one module. That is, when the acquisition module 220 collects the temperature of a pixel, the calculation module 230 simultaneously calculates and records the difference between the temperature value of the pixel and the preset process temperature value. This execution mode makes the system react quickly to the temperature value of the current working area, which is suitable for occasions with high requirements for system sensitivity and accuracy. The calculation module 230 and the acquisition module 220 can also be set separately. That is, the acquisition module 220 first collects the temperature values ​​of all pixels in the current working area and stores them until the processed object in the current working area is completely processed. The calculation module 230 then traverses the temperature value of each pixel one by one, and calculates the actual difference between the temperature value of each pixel and the preset process temperature value. This setting mode is suitable for occasions with low requirements for system sensitivity and accuracy.

[0065] In an optional embodiment, the adjustment module 240 is specifically used to generate a control signal according to the actual difference when the actual difference between the temperature value of one of the pixel points and the preset process temperature value exceeds the preset difference, convert the control signal into a laser light source control signal, and adjust the current output of the laser light source according to the laser light source control signal. Usually, the control signal is a PID control signal. The working area is divided into multiple pixel points, and the laser light source control signal is output according to the difference between the temperature value of each pixel point and the preset process temperature value. Since the current working area is re-divided, the granularity of temperature acquisition becomes smaller, and the laser processing system can respond in time according to the change of the pixel point temperature value, avoiding the situation in the prior art that the temperature sensor outputs the average temperature subjectively ignoring that the temperature value of individual pixel points exceeds or does not reach the process temperature value, and further avoiding the situation that the processed object in the working area where the pixel point is located is burned or poorly welded, resulting in rework, thereby improving the yield of the processed object.

[0066] In an optional embodiment, the motion module 250 is specifically used to control the temperature sensor to move together with the laser light source to form a next working area after the processed object in the current working area is completely processed, and use the next working area as the current working area.

[0067] Furthermore, the constant temperature control device 200 further includes a closing module 260, and the closing module 260 is used to control the power supply of the laser light source to be turned off and stop the output of the laser light source after all the processed objects have been processed.

[0068] The constant temperature control device provided in the embodiment of the present application re-divides the current working area into multiple pixels through the segmentation module 210, thereby reducing the single temperature acquisition area. The acquisition module 220 controls the movement of the temperature sensor and obtains the temperature values ​​of multiple pixels in the current working area. The calculation module 230 calculates the actual difference between the temperature value of each pixel and the preset process temperature value. The adjustment module 240 outputs a laser light source control signal according to the actual difference between the temperature value of each pixel and the preset process temperature value, and adjusts the current output of the laser light source according to the laser light source control signal. The laser processing system can respond in time according to the change of the temperature value of the pixel point, thereby avoiding the situation in the prior art that the temperature sensor outputs the average temperature subjectively ignoring that the temperature value of individual pixels exceeds or fails to reach the process temperature value, further avoiding the situation that the processed object in the working area where the pixel point is located is burned or poorly welded, resulting in rework, thereby improving the yield rate of the processed object. When the constant temperature control device provided in the embodiment of the present application is applied to Micro LED mass processing, it can enable the laser processing system to always maintain a constant temperature mode when processing Micro LEDs in mass, thereby improving the product yield rate in the Micro LED mass processing process.

[0069] See also Figure 4 , Figure 4 A schematic diagram of the structure of a constant temperature control device provided in an embodiment of the present application is shown. The specific embodiment of the present application does not limit the specific implementation of the constant temperature control device.

[0070] like Figure 4 As shown, the constant temperature control device 300 may include: a processor (processor) 302 , a communication interface (Communications Interface) 304 , a memory (memory) 306 , and a communication bus 308 .

[0071] The processor 302, the communication interface 304, and the memory 306 communicate with each other via the communication bus 308. The communication interface 304 is used to communicate with other devices such as a client or other server network elements. The processor 302 is used to execute the program 310, which can specifically execute the relevant steps in the above-mentioned constant temperature control method embodiment.

[0072] Specifically, the program 310 may include program code including computer executable instructions.

[0073] The processor 302 may be a central processing unit (CPU), or an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application. The one or more processors included in the constant temperature control device 300 may be processors of the same type, such as one or more CPUs; or processors of different types, such as one or more CPUs and one or more ASICs.

[0074] The memory 306 is used to store the program 310. The memory 306 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0075] The program 310 can be specifically called by the processor 302 to enable the constant temperature control device 300 to perform the following operations:

[0076] The working area is divided into a plurality of pixels according to the size of the working area and the minimum resolution of the temperature sensor; the temperature sensor is controlled to move and obtain the temperature values ​​of the plurality of pixels in the current working area; the actual difference between the temperature value of each pixel and the preset process temperature value is calculated; a laser light source control signal is output according to the actual difference between the temperature value of each pixel and the preset process temperature value, and the current output of the laser light source is adjusted according to the laser light source control signal; the temperature sensor and the laser light source are controlled to move to form the next working area, and the next working area is used as the current working area; when all the processed objects are processed, the laser light source power is controlled to be turned off to stop the output of the laser light source.

[0077] The processor 302 of the constant temperature control device 300 performs the above operations by calling the program 310. The working area can be re-divided into multiple pixels to reduce the granularity of the single temperature acquisition area. The temperature sensor is controlled to move and the temperature values ​​of multiple pixels in the current working area are obtained. The actual difference between the temperature value of each pixel and the preset process temperature value is calculated. The laser light source control signal is output according to the actual difference between the temperature value of each pixel and the preset process temperature value. The current output of the laser light source is adjusted according to the laser light source control signal. The laser processing system can respond in time according to the change of the temperature value of the pixel point, avoiding the situation in the prior art that the temperature sensor outputs the average temperature subjectively ignoring that the temperature value of individual pixels exceeds or fails to reach the process temperature value, further avoiding the situation that the processed object in the working area where the pixel point is located is burned or the welding is poor, resulting in rework, thereby improving the yield of the processed object. When applied to Micro LED mass processing, the laser processing system can always maintain a constant temperature mode when processing Micro LEDs in mass, thereby improving the product yield in the process of Micro LED mass processing.

[0078] See also Figure 5 , Figure 5 A schematic diagram of the structure of the laser processing system provided in an embodiment of the present application is shown. The specific embodiment of the present application does not limit the specific implementation of the laser processing system.

[0079] The laser processing system 400 includes a temperature acquisition module 410, a constant temperature control device 300, a laser light source 420, and a processed object 430. The temperature acquisition module 410 includes a temperature sensor, which is arranged in the working area of ​​the processed object 430, and is used to collect the temperature value of the working area of ​​the processed object 430 and transmit it to the constant temperature control device 300; at the same time, the temperature acquisition module 410 is mechanically and electrically connected to the constant temperature control device 300, and is used to move to each pixel point of the current working area under the control of the constant temperature control device 300. The laser light source 420 is electrically connected to the constant temperature control device 300, and is used to receive the laser light source 420 control signal output by the constant temperature control device 300; at the same time, the laser light source 420 is used to output a laser beam and irradiate the current working area of ​​the processed object 430, and is mechanically and electrically connected to the constant temperature control device 300, and is used to move to the next working area together with the temperature acquisition module 410 after the constant temperature control device 300 outputs an instruction. The laser light source 420 is further configured to output a laser signal to a working area of ​​the object to be processed 430 , so as to process the object to be processed 430 in the working area of ​​the object to be processed 430 .

[0080] Micro LED displays are made up of millions of three-color RGB chips. Generally speaking, due to the limitations of epitaxial growth technology, it is extremely difficult to simultaneously grow high-quality three-color RGB chips on a large-area epitaxial substrate. Therefore, it is necessary to transfer millions or even tens of millions of micron-sized three-color RGB chips grown on the epitaxial substrate to the drive circuit substrate in sequence to achieve RGB arrangement.

[0081] In a specific embodiment, in combination Figure 1 and Figure 2 As shown, the control process of the laser processing system is as follows: This embodiment takes the process of transferring the three-color RGB chip grown on the epitaxial substrate to the driving circuit substrate as an example.

[0082] The constant temperature control device 300 determines the current working area 101 of the object to be processed 430 according to the instruction of the laser processing system;

[0083] The constant temperature control device 300 controls the laser light source 420 to move to a corresponding position of the current working area 101, so that the laser light beam output by the laser light source 420 just irradiates the current working area 101;

[0084] The constant temperature control device 300 divides the current working area 101 into a plurality of pixel points according to the size of the current working area and the minimum resolution of the temperature sensor of the temperature acquisition module 410;

[0085] The constant temperature control device 300 controls the movement of the temperature sensor and obtains the temperature values ​​of multiple pixel points in the current working area 101; specifically, the constant temperature control device 300 controls the temperature sensor in the temperature acquisition module 410 to move to the first pixel point in the current working area 101 and obtains the temperature value of the first pixel point, and then calculates the actual difference between the temperature value of the first pixel point and the preset process temperature value. When the actual difference between the temperature value of the first pixel point and the preset process temperature value exceeds the preset difference, a control signal is generated according to the actual difference, and the control signal is converted into a control signal of the laser light source 420. The light source 420 controls the signal to adjust the current output of the laser light source 420; and similarly, the constant temperature control device 300 controls the temperature sensor in the temperature acquisition module 410 to move along the X-axis direction to the second pixel point of the current working area 101 and obtains the temperature value of the second pixel point, ... When all the pixel points of the current working area 101 are collected and processed, the constant temperature control device 300 controls the temperature sensor in the temperature acquisition module 410 to move again to the first pixel point of the current working area 101 and obtains the temperature value of the first pixel point, until the processed object of the current working area 101 is completely processed.

[0086] The constant temperature control device 300 controls the temperature sensor and the laser light source 420 to move along the Y-axis direction to form the next working area, and the next working area is used as the current working area. The above process is repeated to achieve the processing of the current working area.

[0087] When the processed objects 430 are all processed, the constant temperature control device 300 controls the power of the laser light source 420 to be turned off, and stops the output of the laser light source 420 .

[0088] The above is only one embodiment of the present application, and this embodiment does not limit the implementation method of the constant temperature control method, device, equipment and laser processing system of the present application.

[0089] An embodiment of the present application provides a computer-readable storage medium, which stores executable instructions. When the executable instructions are executed on a constant temperature control device, the constant temperature control device executes the constant temperature control method in any of the above method embodiments.

Claims

1. A constant temperature control method, It is characterized in that The constant temperature control method comprises the following steps: Dividing the working area into a plurality of pixel points according to the size of the working area and the minimum resolution of the temperature sensor; Controlling the movement of the temperature sensor and acquiring temperature values ​​of a plurality of pixel points in the current working area; Calculate the actual difference between the temperature value of each pixel and the preset process temperature value; A laser light source control signal is output according to the actual difference between the temperature value of each pixel point and the preset process temperature value, and the current output of the laser light source is adjusted according to the laser light source control signal.

2. The constant temperature control method according to claim 1, It is characterized in that The constant temperature control method further comprises the following steps: when the processed object in the current working area is completely processed, controlling the temperature sensor and the laser light source to move to form a next working area, and using the next working area as the current working area.

3. The constant temperature control method according to claim 1, It is characterized in that The constant temperature control method further comprises the following steps: when all the processed objects are processed, the power of the laser light source is controlled to be turned off to stop the output of the laser light source.

4. The constant temperature control method according to claim 1, It is characterized in that The current working area refers to a working area formed by irradiating a preset light spot formed by an optical shaping module with a laser light source as the light source onto the processed object.

5. The constant temperature control method according to claim 1, It is characterized in that The step of outputting a laser light source control signal according to the actual difference between the temperature value of each pixel point and the preset process temperature value, and adjusting the current output of the laser light source according to the laser light source control signal specifically includes: When the actual difference between the temperature value of one of the pixel points and the preset process temperature value exceeds the preset difference, a control signal is generated according to the actual difference, the control signal is converted into a laser light source control signal, and the current output of the laser light source is adjusted according to the laser light source control signal.

6. A constant temperature control device, It is characterized in that The constant temperature control device comprises: A segmentation module, used to segment the working area into a plurality of pixel points according to the size of the working area and the minimum resolution of the temperature sensor; An acquisition module is used to control the movement of the temperature sensor and obtain the temperature values ​​of multiple pixels in the current working area; A calculation module, used to calculate the actual difference between the temperature value of each pixel and the preset process temperature value; An adjustment module, configured to output a laser light source control signal according to an actual difference between the temperature value of each pixel point and a preset process temperature value, and adjust the current output of the laser light source according to the laser light source control signal; The motion module is used to control the temperature sensor and the laser light source to move after the processed object in the current working area is completely processed, so as to form the next working area and use the next working area as the current working area.

7. The constant temperature control device according to claim 6, It is characterized in that The constant temperature control device also includes: The closing module is used to control the power supply of the laser light source to be turned off and stop the output of the laser light source when all the processed objects have been processed.

8. A constant temperature control device, It is characterized in that The constant temperature control device comprises: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other through the communication bus; The memory is used to store executable instructions, and the executable instructions enable the processor to perform the operations of the constant temperature control method as described in any one of claims 1-5.

9. A laser processing system, It is characterized in that The laser processing system includes a temperature acquisition module, the constant temperature control device as claimed in claim 8, a laser light source and a processed object.

10. A computer-readable storage medium, It is characterized in that The storage medium stores executable instructions, and when the executable instructions are executed on the constant temperature control device according to claim 8, the constant temperature control device performs the operation of the constant temperature control method according to any one of claims 1 to 5.

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