Welding methods and apparatus using multiple lasers

Abstract

This invention discloses a multi-laser combination welding method for welding light-emitting units. The light-emitting units have a plurality of units and each emits a single color. The units are welded to pads on a circuit board via electrodes. The emitted colors include a first color and a second color. The method includes: irradiating the pads corresponding to all colors of light-emitting units with a first laser for a first duration to melt the solder on the pads corresponding to the first-color light-emitting units and complete the welding of the first-color light-emitting units; and irradiating the pads corresponding to the second-color light-emitting units with a second laser for a second duration to assist the first laser in melting the solder on the pads corresponding to the second-color light-emitting units, thereby completing the welding of the second-color light-emitting units. The wavelength of the first color light is longer than the wavelength of the second color light. Compared with existing technologies, this invention ensures that each color of light-emitting unit is effectively welded without damage.

Description

Technical Field

[0001] This invention relates to laser welding of light-emitting modules, and more particularly to a welding method and apparatus for welding light-emitting units on a circuit board using multiple lasers in synergy. Background Technology

[0002] The manufacturing process of Mini / Micro LED display modules requires soldering a large number of red, green, and blue LED chips onto a PCB substrate, followed by sealing the LED chips with an encapsulation layer. Traditionally, the three colors of LED chips are transferred to the PCB substrate and then soldered using reflow soldering. However, during the reflow soldering process, it's difficult to accurately apply heat to the connection points between the LED chips and the PCB substrate. The entire heating process also heats both the LED chips and the PCB substrate itself, causing varying degrees of deformation on the PCB substrate. Ultimately, this results in poor display quality when the Mini / Micro LED display modules are assembled into a display screen.

[0003] To address the aforementioned issues, laser welding can be used to heat and weld the connection points between the LED chip and the PCB substrate using laser energy. However, different LED colors require different laser powers for welding; for example, red LED chips require less power than green and blue LED chips. If a uniform low-power welding is used, green and blue LED chips may not be effectively welded, while if a uniform high-power welding is used, red LED chips are easily damaged.

[0004] The applicant previously filed a patent (welding apparatus and welding method using the same apparatus, CN113399829B, application date 2021 / 7 / 9), which disclosed the use of a light source for batch welding. It also utilized a light guide plate with sub-light guides of different transmittance, each sub-light guide corresponding to one of three LED colors. This technology enables batch welding while avoiding heating the PCB substrate itself during welding, effectively reducing PCB substrate deformation. However, in current light guide plate manufacturing, controlling the transmittance of sub-light guides corresponding to the same LED color is difficult, and differences in the actual transmittance of identical sub-light guides result in inconsistent welding quality. Therefore, an alternative welding solution needs to be found. Summary of the Invention

[0005] The purpose of this invention is to provide a welding method and apparatus using multiple lasers. The main laser is set according to the power required by the light-emitting unit of the color with the longest wavelength to perform the main welding of light-emitting units of all colors. Other auxiliary lasers are used to perform supplementary welding of light-emitting units of other colors, so that each color of light-emitting unit can be effectively welded without being damaged.

[0006] To achieve the above objectives, this invention discloses a multi-laser combination welding method for welding electrodes of light-emitting units to pads on a circuit board. The light-emitting units are multiple and each has a single emission color. The light-emitting units are welded to pads on the circuit board via electrodes. The emission color includes a first color and a second color. The method includes: irradiating the pads corresponding to all light-emitting units of all colors with a first laser for a first duration to melt the solder on the pads corresponding to the first-color light-emitting units and complete the welding of the first-color light-emitting units; and irradiating the pads corresponding to the second-color light-emitting units with a second laser for a second duration to assist the first laser in melting the solder on the pads corresponding to the second-color light-emitting units, thereby completing the welding of the second-color light-emitting units. The wavelength of the first color light is greater than the wavelength of the second color light.

[0007] Compared with the prior art, the present invention can set the main laser (first laser) according to the power required by the light-emitting unit of the color with the longest wavelength (first color) to perform the main welding of light-emitting units of all colors, and use another auxiliary laser (second laser) to perform supplementary welding of light-emitting units of other colors, so that each color of light-emitting unit can be effectively welded without being damaged.

[0008] Preferably, while irradiating the pads corresponding to all color light-emitting units with a first laser for a fourth duration, irradiating the pads corresponding to the second color light-emitting units with a second laser for a second duration, the fourth duration is shorter than the first duration, and the time difference between the first duration and the fourth duration is less than or equal to a preset value and greater than 0, so that the fourth duration is close to the first duration. This scheme ensures that the heating of the second color light-emitting units by the first laser and the heating of the second color light-emitting units by the second laser are continuous, effectively improving the working efficiency of the laser source, reducing working time, preventing the pads from cooling down due to the heating interval between the first and second lasers, affecting the melting speed of the solder on the pads, and allowing the invention to first perform main heating with the first laser, and then use the second laser for auxiliary heating after heating for a period of time. Furthermore, while ensuring the continuous operation of the first and second lasers, interference of the second laser on the first laser is minimized.

[0009] Specifically, a laser source is used to irradiate the light-emitting unit with a first laser and a second laser. The laser source includes a first laser source that emits the first laser and a second laser source that emits the second laser. The second laser source can move along the arrangement direction of the light-emitting units on the circuit board to heat and solder the pads corresponding to the second color light-emitting units on the circuit board. When the first laser source emits the first laser and irradiates the pads corresponding to all colors of light-emitting units for a fourth duration, the second laser source is moved to the position corresponding to the second color light-emitting unit and emits the second laser, so that the second laser irradiates the pads corresponding to the second color light-emitting unit for a second duration.

[0010] Preferably, the second laser acts simultaneously with the first laser on the pads corresponding to the light-emitting units of the second color for at least a portion or all of the second duration, effectively improving the welding efficiency of the light-emitting units of the second color.

[0011] Specifically, a laser coupling element is disposed on the circuit board at the position corresponding to the electrode of the second-color light-emitting unit. The laser coupling element can transmit the second laser and reflect the first laser onto the pad corresponding to the second-color light-emitting unit, so that the first laser and the second laser act together on the pad corresponding to the second-color light-emitting unit, and so that the second laser acts on the pad corresponding to the second-color light-emitting unit simultaneously with the first laser for at least part of the duration or for all of the second duration. This scheme allows the laser sources of the first laser and the second laser to be set independently, and the laser sources of the first laser and the second laser are superimposed by the laser coupling element fixed above the circuit board.

[0012] Preferably, the light emission color further includes a third color, and the welding method further includes: irradiating the pads corresponding to the light emission units of the third color with a third laser for a third duration to assist the first laser in melting the solder on the pads corresponding to the light emission units of the third color, thereby completing the welding of the light emission units of the third color, wherein the wavelength of the second color light is greater than the wavelength of the third color light.

[0013] Preferably, when the first laser is irradiated onto the pads corresponding to all color light-emitting units for a fifth duration, the third laser is irradiated onto the pads corresponding to the third color light-emitting units for a third duration. The fifth duration is shorter than the first duration, and the time difference between the first duration and the fifth duration is less than or equal to a preset value and greater than 0, so that the fifth duration is close to the first duration. This scheme ensures that the heating of the third color light-emitting units by the first laser and the heating of the third color light-emitting units by the third laser are continuous, effectively improving the working efficiency of the laser source, reducing working time, preventing the pads from cooling down due to the heating interval between the first and third lasers, which would affect the melting speed of the solder on the pads, and also allows the invention to first perform main heating with the first laser, and then use the third laser for auxiliary heating after heating for a period of time.

[0014] Specifically, a laser source is used to irradiate the light-emitting unit with a first laser, a second laser, and a third laser. The laser source includes a first laser source emitting the first laser, a second laser source emitting the second laser, and a third laser source emitting the third laser. The third laser source can move along the arrangement direction of the light-emitting units on the circuit board to heat and solder the pads corresponding to the third color light-emitting units on the circuit board. When the first laser source emits the first laser and irradiates the pads corresponding to all colors of light-emitting units for a fifth duration, the third laser source is moved to the position corresponding to the third color light-emitting unit and emits the third laser, so that the third laser irradiates the pads corresponding to the third color light-emitting unit for a third duration.

[0015] Preferably, the third laser acts on the pads corresponding to the third color light-emitting unit simultaneously with the first laser for at least part or all of its duration, effectively improving the welding efficiency of the third color light-emitting unit.

[0016] Specifically, a laser coupling element is provided on the circuit board at the position corresponding to the electrode of the third color light-emitting unit. The laser coupling element can transmit the third laser and reflect the first laser to the pad corresponding to the third color light-emitting unit, so that the first laser and the third laser act together on the pad corresponding to the third color light-emitting unit, so that the third laser acts on the pad corresponding to the third color light-emitting unit simultaneously with the first laser for at least part of the duration or for all of the third duration.

[0017] Specifically, the output power of the third laser is greater than the output power of the second laser, the first duration is longer than the third duration, and the first duration is longer than the second duration.

[0018] Preferably, the laser source includes a first laser source that emits a first laser and a second laser source that emits a second laser. The first laser source and the second laser source are respectively controlled to move along the arrangement direction of the light-emitting units of the corresponding color on the circuit board to emit corresponding lasers to the pads of the light-emitting units of the corresponding color on the circuit board.

[0019] Specifically, the laser source includes a first laser source emitting a first laser, a second laser source emitting a second laser, and a third laser source emitting a third laser. The first, second, and third laser sources can each move along the arrangement direction of the corresponding color light-emitting units on the circuit board to irradiate the pads of the corresponding color light-emitting units on the circuit board with the corresponding laser. This invention uses three independent laser sources to adjust the soldering status of the three colors of light-emitting units respectively.

[0020] Preferably, the laser source includes a first laser source emitting a first laser and a second laser source emitting a second laser, wherein the first laser source is a surface laser and the second laser source is a line light source or a point light source; or, the first laser source is a line laser and the second laser source is a point laser. The welding of the two color-emitting units is controlled by two independent laser sources.

[0021] Specifically, the laser source includes a first laser source emitting a first laser, a second laser source emitting a second laser, and a third laser source emitting a third laser. The first laser source is a surface laser, and the second and third laser sources are line light sources or point light sources; or, the first laser source is a line laser, and the second and third laser sources are point lasers. The welding of the three color light-emitting units is controlled by three independent laser sources.

[0022] Specifically, the first color is red light, the second color is green light, and the third color is blue light.

[0023] Preferably, a light guide plate is disposed on the circuit board, and the light guide plate has a light guide portion corresponding to the pads on the circuit board. A laser source is used to deliver the corresponding laser to the corresponding pad through the light guide portion.

[0024] Preferably, for the pads corresponding to the light-emitting units of the first color, the duration of the first laser's action and the duration of the second laser's action are continuous or overlapped. For the pads corresponding to the light-emitting units of the second color, the duration of the first laser's action and the duration of the third laser's action are continuous or overlapped.

[0025] The present invention also discloses a multi-laser combination welding apparatus, comprising: a laser source for irradiating a pad on a circuit board with a laser to heat the solder on the pad; a memory for storing at least one executable instruction; and a processor for causing the processor to perform the operation of the multi-laser combination welding method as described above. Attached Figure Description

[0026] Figure 1 This is a structural diagram of the circuit board of the present invention, which is subjected to multi-laser welding.

[0027] Figure 2 yes Figure 1 A magnified view of a portion of the image.

[0028] Figure 3 This is a structural diagram of the substrate.

[0029] Figure 4 This is a structural diagram of a circuit board.

[0030] Figures 5a to 5d This is a flowchart of a welding method using multiple laser combinations in the first embodiment of the present invention.

[0031] Figure 6 yes Figure 5b A magnified view of a portion of the image.

[0032] Figure 7 This is a timing diagram of the welding of multiple color light-emitting units under corresponding laser irradiation in the first embodiment of the present invention.

[0033] Figure 8 This is a schematic diagram illustrating the working principle of the welding method using multiple laser combinations in the second embodiment of the present invention.

[0034] Figure 9 This is a timing diagram of the welding of multiple color light-emitting units under corresponding laser irradiation in the second embodiment of the present invention. Detailed Implementation

[0035] To illustrate the technical content, structural features, objectives, and effects of the present invention in detail, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0036] This invention discloses a multi-laser combination welding method for welding electrodes of a light-emitting unit to corresponding pads on a circuit board. (Refer to...) Figure 3 and Figure 4 The circuit board 10 includes a substrate 11, pads 12 formed on the substrate 11, and light-emitting units 13 mounted on the substrate 11. The light-emitting units 13 are multiple and have a single light-emitting color. The light-emitting units 13 are soldered to the pads 12 through electrodes. The light-emitting color includes a first color and a second color.

[0037] The light-emitting unit 13 can be an LED chip, an LED single-chip package, a single-color light-emitting chip in a multi-color LED package, or a color unit in a multi-color light-emitting chip. The LED single-chip package includes a BT substrate, an LED chip, and a packaging layer. The LED chip is soldered onto the BT substrate, and the packaging layer seals and encapsulates the LED chip. The LED chip can be connected to the PCB substrate through the BT substrate. When soldering the light-emitting unit 13, solder (which can be tin) is first applied to the solder pads 12 on the substrate 11. The light-emitting unit 13 is then placed on the substrate 11, with the electrodes of the light-emitting unit 13 aligned with the solder pads 12. The solder pads 12 are then heated by a laser to melt the solder, and the light-emitting unit 13 is soldered onto the solder pads 12 on the substrate 11.

[0038] refer to Figure 4 In this embodiment, the light-emitting unit 13 has three colors, namely red light-emitting unit 131, green light-emitting unit 132 and blue light-emitting unit 133. Of course, the color of the light-emitting unit 13 is not limited to these, and can also be four colors or other three colors or two colors, etc.

[0039] refer to Figure 1 , Figure 2 and Figure 7 The multi-laser combination welding method of the present invention includes: using a first laser source 31 to irradiate the pads 12 corresponding to all color light-emitting units 131 and 132 with a first laser L1 for a first duration T1, so that the solder on the pads 12 corresponding to the first color light-emitting units melts and the welding of the red light-emitting unit 131 is completed; using a second laser source 32 to irradiate the pads 12 corresponding to the green light-emitting unit 132 with a second laser L2 for a second duration T2, so as to assist the first laser L1 in melting the solder on the pads 12 corresponding to the second color light-emitting units, thereby completing the welding of the green light-emitting unit 132, wherein the wavelength of the first color light is greater than the wavelength of the second color light.

[0040] In this invention, a light guide plate 20 is disposed on the circuit board 10. The light guide plate 20 has light guide portions 21 corresponding to the pads 12 on the circuit board 10. A laser source is used to deliver the corresponding laser to the corresponding pad 12 through the light guide portions 21. In this embodiment, all light-emitting units 13 are flip-chip. When the light-emitting unit 13 is transferred to the corresponding pad 12, the two electrodes of each light-emitting unit 13 contact the two pads 12 respectively. In other cases, such as when the red light-emitting unit 131 uses a vertical chip structure, one electrode of the red light-emitting unit 131 contacts one corresponding pad 12, and the other electrode needs to be connected to another pad through wire bonding process in a subsequent process. In this case, the number of light guide portions 21 on the light guide plate 20 will be reduced accordingly, that is, the light guide portions 21 on the light guide plate 20 correspond one-to-one with the pads 12 that need to be soldered.

[0041] refer to Figure 7 In this embodiment, when the first laser source 31 irradiates the pads 12 corresponding to the light-emitting units 131, 132, and 133 of all colors with the first laser L1 for a fourth duration t4, the second laser L2 is irradiated on the pad 12 corresponding to the green light-emitting unit 132 for a second duration T2. ​​The fourth duration t4 is less than the first duration T1, and the time difference between the first duration T1 and the fourth duration t4 is less than or equal to a preset value and greater than 0, so that the fourth duration t4 is close to the first duration T1.

[0042] refer to Figures 5a to 5d This invention uses a laser source to irradiate a first laser L1 and a second laser L2 onto the light-emitting units. The laser source includes a first laser source 31 that emits the first laser L1 and a second laser source 32 that emits the second laser L2. In a first embodiment of this invention, the second laser source 32 can move along the arrangement direction of the light-emitting units on the circuit board 10 to heat and solder the pads 12 corresponding to the green light-emitting units 132 on the circuit board 10. The first laser source 31 can move along the arrangement direction of the light-emitting units on the circuit board 10 to heat and solder the pads 12 corresponding to all the light-emitting units 131, 132, and 133 on the circuit board 10.

[0043] Specifically, when the first laser source 31 emits a first laser L1 and the first laser L1 illuminates the pads 12 corresponding to all the light-emitting units 131 and 132 of all colors for a fourth duration t4, the second laser source 32 is moved to the position corresponding to the green light-emitting unit 132 and emits a second laser L2, so that the second laser L2 illuminates the pads 12 corresponding to the green light-emitting unit 132 for a second duration T2.

[0044] For the better option, refer to Figure 7The welding method further includes: using a third laser source 33 to irradiate the pad 12 corresponding to the blue light-emitting unit 133 with a third laser L3 for a third duration T3, so as to assist the first laser L1 in melting the solder on the pad 12 corresponding to the blue light-emitting unit 133, thereby completing the welding of the blue light-emitting unit 133, wherein the wavelength of the second color light wave is greater than the wavelength of the third color light wave.

[0045] Continue to refer to Figure 7 When the first laser L1 is irradiated onto the pads 12 corresponding to the light-emitting units 131, 132, and 133 of all colors for a fifth duration t5, the third laser L3 is irradiated onto the pad 12 corresponding to the blue light-emitting unit 133 for a third duration T3. The fifth duration t5 is less than the first duration T1, and the time difference between the first duration T1 and the fifth duration t5 is less than or equal to a preset value and greater than 0, so that the fifth duration t5 is close to the first duration T1.

[0046] refer to Figures 5a to 5d The laser source also includes a third laser source 33 that emits a third laser L3. The third laser source 33 can move along the arrangement direction of the light-emitting units on the circuit board 10 to heat and solder the pads 12 corresponding to the blue light-emitting units 133 on the circuit board 10.

[0047] Specifically, when the first laser source 31 emits a first laser L1 and the first laser L1 illuminates the pads 12 corresponding to all the light-emitting units 131, 132, and 133 of all colors for a fifth duration t5, the third laser source 33 is moved to the position corresponding to the blue light-emitting unit 133 and emits a third laser L3, so that the third laser L3 illuminates the pads 12 corresponding to the blue light-emitting unit 133 for a third duration T3.

[0048] In this embodiment, the third laser source 33 and the second laser source 32 are mounted on corresponding movable supports and moved. In this embodiment, the fifth duration t5 is less than the fourth duration t4. When the first laser L1 illuminates the pads 12 corresponding to all the light-emitting units 131, 132, and 133 of all colors and continues for the fifth duration t5, the second laser source 32 and the third laser source 33 are moved along... Figure 5b The laser source moves in the direction of the middle arrow so that the second laser L2 of the second laser source 32 illuminates the green light-emitting unit 132, and the third laser L3 of the third laser source 33 illuminates the blue light-emitting unit. Of course, the second laser source 32 and the third laser source 33 can also move independently through independent moving mechanisms, and their moving directions can be the same or opposite.

[0049] In this embodiment, the output power of the third laser L3 is greater than the output power of the second laser L2, and the output power of the third laser L3 is less than the output power of the first laser L1. Of course, the output power of the second laser L2 and the output power of the third laser L3 can also be greater than the output power of the first laser L1.

[0050] In this embodiment, the first duration T1 is longer than the third duration T3, and the first duration T1 is longer than the second duration T2. ​​Of course, the first duration T1 may also be shorter than the second duration T2, and the first duration T1 may also be shorter than the third duration T3.

[0051] In this embodiment, the third duration T3 is greater than the second duration T2. ​​Of course, the third duration T3 may also be equal to or less than the second duration T2.

[0052] The output power and duration T1 of the first laser L1 are determined by the welding requirements of the light-emitting unit 131 with the largest wavelength among the light-emitting units 13, ensuring that the welding of the light-emitting unit 131 is sufficient without damaging it. The output power and duration T2 of the second laser L2 are determined by the difference between the welding energy required for the green light-emitting unit 132 and the welding energy required for the red light-emitting unit 131, ensuring that the welding of the green light-emitting unit 132 is sufficient without damaging it. The output power and duration T3 of the third laser L3 are determined by the difference between the welding energy required for the blue light-emitting unit 133 and the welding energy required for the red light-emitting unit 131, ensuring that the welding of the blue light-emitting unit 133 is sufficient without damaging it. The specific output power and duration of the laser source are set according to the above criteria and are not limited to the specific values ​​given in the examples above. The present invention enables the welding status of the red light-emitting unit 131 to be independently adjusted and determined by the first laser source 31, the welding status of the green light-emitting unit 132 to be independently adjusted and determined by the second laser source 32, and the welding status of the blue light-emitting unit 133 to be independently adjusted and determined by the third laser source 33.

[0053] In this embodiment, the first laser source 31 is a surface laser, and the second laser source 32 and the third laser source 33 are line light sources. Of course, in another embodiment, the first laser source 31 is a surface laser, and the second laser source 32 and the third laser source 33 are point light sources. In yet another embodiment, the first laser source 31 is a line laser, and the second laser source 32 and the third laser source 33 are point light sources. This invention controls the welding of the three color light-emitting units separately using three independent laser sources. In yet another embodiment, the first laser source 31 is a line laser, and the second laser source 32 and the third laser source 33 are line lasers.

[0054] refer to Figure 1 and Figure 2In this invention, during soldering, the entire circuit board 10 is divided into one or more working areas. A first laser source 31 is movably positioned above the circuit board 10, allowing the first laser source 31 to move movably within the current working area. The effective area of ​​the first laser source 31 is 'a'. The first laser source 31 moves along the current working area at a preset speed. Figure 5a The second laser source 32 is movably positioned above the circuit board 10, allowing it to move within the current working area. The effective area of ​​the second laser source 32 is b. The second laser source 32 moves along the current working area at a preset speed. Figure 5b The laser source moves in the direction of the middle arrow and stays at the green light-emitting unit 132 for a preset time to heat the corresponding pad 12 at the green light-emitting unit 132. The third laser source 33 is movably disposed above the circuit board 10, allowing it to move movably within the current working area. The effective area of ​​the third laser source 33 is c. The second laser source 32 moves along the current working area at a preset speed. Figure 5b The device moves in the direction of the middle arrow and stays at the blue light-emitting unit 133 for a preset time, heating the pad 12 corresponding to the blue light-emitting unit 133.

[0055] refer to Figures 5a to 7 The specific working process of the present invention is described as follows: A light guide plate 20 is placed above a circuit board 10 on which the light-emitting unit 13 is mounted, such that the light guide portion 21 corresponds to the position of the pad 12 on the circuit board 10. The first laser source 31 is moved to the working area, and the first laser source 31 is controlled to move along... Figure 5a Move to the first active area a in the current workspace (reference) in the direction of the middle arrow. Figure 5b At this time, the first laser L1 emitted by the first laser source 31 illuminates the red light-emitting unit 131, the green light-emitting unit 132, and the blue light-emitting unit 133. When the illumination time reaches the fifth duration t5, the third laser source 33 is controlled to move to the corresponding position in the direction of the arrow (see reference). Figure 5b At this time, the third laser L3 emitted by the third laser source 33 illuminates the blue light-emitting unit 133; when the illumination time of the first laser L1 reaches the fourth duration t4, the second laser source 32 is controlled to move to the corresponding position in the direction of the arrow, at which time the second laser L2 emitted by the second laser source 33 illuminates the green light-emitting unit 132 (see reference). Figure 5b When the irradiation duration of the first laser L1 reaches the first duration T1, the first laser source 31 is controlled to move along the arrow direction to the next working area (e.g., ...) of the current working area. Figure 5c As shown), when the first laser irradiates the second action area for a fifth time duration t5, the third laser source 33 is controlled to move along the arrow direction to the corresponding position (see reference). Figure 5dAt this time, the third laser L3 emitted by the third laser source 33 illuminates the blue light-emitting unit 133; when the illumination time of the first laser L1 reaches the fourth duration t4, the second laser source 32 is controlled to move to the corresponding position in the direction of the arrow, at which time the second laser L2 emitted by the second laser source 33 illuminates the green light-emitting unit 132 (see reference). Figure 5d In sequence, complete the welding of all light-emitting units 13 in the current working area.

[0056] refer to Figure 8 and Figure 9 This is a second embodiment of the present invention, distinct from the first embodiment. In this second embodiment, the second laser L2 acts simultaneously with the first laser L1 on the pad 12 corresponding to the green light-emitting unit 132 for at least a portion or all of the second duration T2, effectively improving the welding efficiency of the green light-emitting unit 132. The third laser L3 acts simultaneously with the first laser L1 on the pad 12 corresponding to the blue light-emitting unit 133 for at least a portion or all of the duration, effectively improving the welding efficiency of the blue light-emitting unit 133.

[0057] refer to Figure 8 A laser coupling element 40 is provided on the circuit board 10 at the position corresponding to the electrode of the green light-emitting unit 132. The laser coupling element 40 can transmit the second laser L2 and reflect the first laser L1 to the pad 12 corresponding to the green light-emitting unit 132, so that the first laser L1 and the second laser L2 act together on the pad 12 corresponding to the green light-emitting unit 132, so that the second laser L2 acts on the pad 12 corresponding to the green light-emitting unit 132 simultaneously with the first laser L1 for at least part of the duration or all of the second duration T2.

[0058] refer to Figure 8 A laser coupling element 40 is provided on the circuit board 10 at the position corresponding to the electrode of the blue light-emitting unit 133. The laser coupling element 40 can transmit the third laser L3 and reflect the first laser L1 to the pad 12 corresponding to the blue light-emitting unit 133, so that the first laser L1 and the third laser L3 act together on the pad 12 corresponding to the blue light-emitting unit 133, so that the third laser L3 acts on the pad 12 corresponding to the blue light-emitting unit 133 simultaneously with the first laser L1 for at least part of the duration or all of the third duration T3.

[0059] In this embodiment, the first laser source 31 is movably mounted on the bracket and moves along the arrangement of the light-emitting units 13 on the circuit board 10. The laser coupling component 40 is movably mounted on the frame and moves synchronously with the first laser source 31. The laser coupling component 40 and the first laser source 31 are mounted on the same bracket or driven synchronously by the same moving mechanism. Of course, the laser coupling component 40 and the first laser source 31 can also be controlled by different moving mechanisms to move asynchronously. The second laser source 32 and the third laser source 33 can be fixed on the frame or movably mounted on the frame and move along the lateral arrangement of the working area on the circuit board. When welding in a working area, the second laser source 32 and the third laser source 33 do not need to move. Only the movement of the laser coupling component 40 causes the second laser L2 and the third laser L3 to move and irradiate the corresponding positions respectively.

[0060] Specifically, this scheme allows the laser sources of the first laser L1 and the second laser L2 to be set independently, and the laser sources of the first laser L1 and the second laser L2 are superimposed by the laser coupler 40 fixed above the circuit board 10.

[0061] refer to Figure 9 When starting work, the first laser source 31 is moved to the corresponding position of the light-emitting units 131, 132, and 133 that need to be welded. The laser couplings 40 of the second laser source 32 and the third laser source 33 are moved to the corresponding positions of the green light-emitting unit 132 and the blue light-emitting unit 133 that need to be welded. The first laser source 31, the second laser source 32, and the third laser source 33 are turned on. The first laser source 31 is used to irradiate all the light-emitting units 131, 132, and 133 for a first duration T1. The second laser source 32 is used to irradiate the green light-emitting unit 132 for a second duration T2. ​​The third laser source 33 is used to irradiate the blue light-emitting unit 133 for a third duration T3. T2 and T3 are both less than T1. When the irradiation time is reached, the second laser source 32 and the third laser source 33 are turned off accordingly. Of course, the irradiation time of the second laser source 31 and the third laser source 33 can also start after the first laser source T1 has irradiated for x time, as long as the sum of x time and T2 or T3 time is less than or equal to the first time T1.

[0062] The above embodiment is based on the synchronous movement of the laser coupler 40 and the first laser source 31. The red light-emitting unit 131, the green light-emitting unit 132 and the blue light-emitting unit 133 form a light-emitting module. When the first laser source 31 illuminates n light-emitting modules in the horizontal direction, there are n second laser sources 32 and third laser sources 33. The laser coupler 40 corresponds to the second laser sources 32 and the third laser sources 33, and n is greater than or equal to 1.

[0063] Of course, the laser coupler 40 and the first laser source 31 can also be moved separately. In this case, if the first laser source 31 corresponds to n light-emitting modules and n is greater than or equal to 1, it is preferable that n times the second duration T2 is less than or equal to the first duration T1. When the irradiation duration of the second laser source 32 reaches the second duration T2, the laser coupler 40 corresponding to the second laser source 32 is moved to the corresponding green light-emitting unit 132 in the next light-emitting module. Thus, within the first duration T1, the second laser source 32 emits a second laser L2 of duration T2 to all green light-emitting units 133 within the coverage area of ​​the current first laser source 31. When the irradiation duration of the third laser source 33 reaches the third duration T3, the laser coupler 40 corresponding to the third laser source 33 is moved to the corresponding blue light-emitting unit 133 in the next light-emitting module. Thus, within the first duration T1, the third laser source 32 emits a third laser L3 of duration T3 to all blue light-emitting units 133 within the coverage area of ​​the current first laser source 31.

[0064] The present invention discloses a welding apparatus for multiple laser combinations, comprising: a laser source for emitting laser light onto a circuit board 10 to be welded to heat solder on pads on the circuit board 10; a memory for storing at least one executable instruction; and a processor for causing the operation of a welding method for multiple laser combinations.

[0065] In this invention, the laser source includes a first laser source 31, a second laser source 32, and a third laser source 33.

[0066] The welding device with multiple laser combinations also includes a light guide plate 20, which has a light guide portion 21 corresponding to the pad 12 on the circuit board 10. The light guide portion 21 can deliver the laser emitted by the laser source to the corresponding pad 12.

[0067] In this invention, the laser irradiation time for each light-emitting unit 131, 132, and 133 is continuous. For the pad 12 corresponding to the green light-emitting unit 132, the action time of the first laser L1 and the action time of the second laser L2 are continuous or overlapped. For the pad 12 corresponding to the blue light-emitting unit 132, the action time of the first laser L1 and the action time of the third laser L3 are continuous or overlapped.

[0068] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A multi-laser combined soldering method for corresponding soldering of electrodes of a light emitting unit with pads on a circuit board, the light emitting unit having several and having a single light emitting color, the light emitting unit being corresponding soldered with the electrodes with the pads on the circuit board, the light emitting color comprising a first color and a second color, characterized in that: The method comprises: irradiating the pads corresponding to the light-emitting units of all colors with first laser light for a first duration to melt the solder on the pads corresponding to the light-emitting units of the first color and complete the soldering of the light-emitting units of the first color; irradiating the pads corresponding to the light-emitting units of the second color with second laser light for a second duration to assist the first laser light in melting the solder on the pads corresponding to the light-emitting units of the second color, thereby completing the soldering of the light-emitting units of the second color, the wavelength of light of the first color being greater than the wavelength of light of the second color.

2. The method of welding of claim 1, wherein: When irradiating the pads corresponding to the light-emitting units of all colors with first laser light for a fourth duration, irradiate the pads corresponding to the light-emitting units of the second color with second laser light for a second duration, the fourth duration being less than the first duration, the time difference between the first duration and the fourth duration being less than or equal to a preset value and greater than 0, so that the fourth duration is adjacent to the first duration.

3. The method of welding of claim 2, wherein: Using a laser source to irradiate the light-emitting units with first laser light and second laser light, the laser source comprising a first laser source emitting first laser light and a second laser source emitting second laser light, the second laser source being movable along the arrangement direction of the light-emitting units on the circuit board to heat and solder the pads corresponding to the light-emitting units of the second color on the circuit board; When the first laser source emits first laser light and the first laser light irradiates the pads corresponding to the light-emitting units of all colors for a fourth duration, the second laser source is moved to the position corresponding to the light-emitting units of the second color and emits second laser light, so that the second laser light irradiates the pads corresponding to the light-emitting units of the second color for a second duration.

4. The method of welding of claim 1, wherein: The second laser light acts on the pads corresponding to the light-emitting units of the second color at least partially simultaneously with the first laser light during the second duration.

5. The method of claim 1, wherein: A laser coupling member is arranged at a position corresponding to the electrode corresponding to the light-emitting units of the second color on the circuit board, the laser coupling member being capable of transmitting the second laser light and reflecting the first laser light to the pads corresponding to the light-emitting units of the second color, so that the first laser light and the second laser light act on the pads corresponding to the light-emitting units of the second color together, and the second laser light acts on the pads corresponding to the light-emitting units of the second color at least partially simultaneously with the first laser light during the second duration.

6. The method of welding of claim 1, wherein: The light-emitting colors further comprise a third color, and the soldering method further comprises: irradiating the pads corresponding to the light-emitting units of the third color with third laser light for a third duration to assist the first laser light in melting the solder on the pads corresponding to the light-emitting units of the third color, thereby completing the soldering of the light-emitting units of the third color, the wavelength of light of the second color being greater than the wavelength of light of the third color.

7. The method of welding of claim 6, wherein: When the first laser is irradiated to the pads corresponding to the light emitting units of all colors for a fifth time length, the third laser is irradiated to the pads corresponding to the light emitting units of the third color for a third time length, the fifth time length is less than the first time length, and a time difference between the first time length and the fifth time length is less than or equal to a preset value and greater than 0, so that the fifth time length is adjacent to the first time length.

8. The method of welding of claim 7, wherein: The first laser, the second laser and the third laser are irradiated to the light emitting units by using a laser source, the laser source includes a first laser source for emitting the first laser, a second laser source for emitting the second laser and a third laser source for emitting the third laser, and the third laser source is movable along the arrangement direction of the light emitting units on the circuit board to heat the pads corresponding to the light emitting units of the third color on the circuit board; When the first laser is emitted by using the first laser source and irradiated to the pads corresponding to the light emitting units of all colors for a fifth time length, the third laser source is moved to a position corresponding to the light emitting units of the third color and emits the third laser, so that the third laser is irradiated to the pads corresponding to the light emitting units of the third color for a third time length.

9. The method of claim 6, wherein: The third laser acts on the pads corresponding to the light emitting units of the third color at least partially or entirely simultaneously with the first laser.

10. The method of claim 9, wherein: A laser coupling member is arranged at a position corresponding to the electrode corresponding to the light emitting units of the third color on the circuit board, the laser coupling member can transmit the third laser and reflect the first laser to the pads corresponding to the light emitting units of the third color, so that the first laser and the third laser act on the pads corresponding to the light emitting units of the third color together, and the third laser acts on the pads corresponding to the light emitting units of the third color at least partially or entirely simultaneously with the first laser.

11. The method of claim 6, wherein: The output power of the third laser is greater than the output power of the second laser, the first time length is longer than the third time length, and the first time length is longer than the second time length.

12. The method of welding of claim 6, wherein: The laser source includes a first laser source for emitting the first laser, a second laser source for emitting the second laser and a third laser source for emitting the third laser, the first laser source is a surface laser, and the second laser source and the third laser source are linear light sources or point light sources; or the first laser source is a linear laser, and the second laser source and the third laser source are point lasers.

13. The method of welding of claim 6, wherein: The first color is red light, the second color is green light, and the third color is blue light.

14. The method of welding of claim 1, wherein: A light guide plate is arranged on the circuit board, the light guide plate has a light guide part corresponding to the pads on the circuit board, and a laser source is used to transmit corresponding laser to the pads through the light guide part.

15. A multi-laser assembly welding device, characterized by: The laser source irradiates laser to the pads on the circuit board to heat the solder on the pads; The memory stores at least one executable instruction; The processor executes the operations of the multi-laser combined welding method according to any one of claims 1-14 by executing the executable instruction. ​

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