Optical film laminating device for Mini LED backlight module and laminating process of optical film laminating device

Abstract

The optical film laminating device comprises a laminating device shell, a sealing cavity, a vacuum pump, an extrusion plate, a hydraulic telescopic rod, a pretreatment box and the like, and the pretreatment box is provided with a plasma generator, a power controller, a time controller and the like. A motor, a guide rod, a gradient curing lamp and related regulators and controllers are further included. The process comprises the steps of pretreatment, glue coating, vacuum laminating and gradient curing. The plasma generator pretreats the membrane material, the surface activity and the microstructure are improved, and dependence on high-temperature heating is reduced. The pressure control unit accurately controls the laminating pressure, and the gradient curing lamp adopts gradient curing. And various process parameters are accurately controlled through a power controller, a time controller, a light intensity controller, a curing energy controller and the like. The problems of glue volatilization bubbles and film material warping caused by high temperature are avoided, the flatness and the laminating yield of the film material are improved, tight laminating is performed in a vacuum environment by adopting mechanical staged pressure control, and the equipment cost is saved.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to an optical film bonding device and bonding process for MiniLED backlight modules. Background Technology

[0002] The optical film bonding device for MiniLED backlight modules adopts an integrated design of a high-precision alignment mechanism and a vacuum adsorption platform. It achieves micron-level precise alignment between the optical film and the MiniLED substrate through a vision positioning system. Equipped with a multi-temperature zone pressure control module and a closed-loop feedback system, it dynamically adjusts the bonding process parameters. Combined with a flexible pressing head and a multi-axis linkage robotic arm, it can efficiently and seamlessly bond curved or irregularly shaped backlight modules. It integrates an anti-static dust removal device and an automatic defect detection module to ensure no bubbles, wrinkles, or scratches, thereby improving the optical uniformity and mass production yield of MiniLED backlight modules.

[0003] In existing MiniLED optical film bonding processes, traditional hot pressing methods are prone to causing adhesive evaporation and air bubbles due to high temperatures. Vacuum bonding, on the other hand, has high equipment costs and stringent requirements for film flatness. Generally, the adhesive layer is cured by heating and pressurizing, but high temperatures can easily cause adhesive evaporation and air bubbles. Furthermore, the difference in the thermal expansion coefficient of the film materials can lead to warping. In addition, the removal of air in a vacuum environment increases equipment costs and has stringent requirements for film flatness, resulting in a low yield rate. Summary of the Invention

[0004] This invention provides the following technical solution: an optical film bonding device for a MiniLED backlight module, comprising: a bonding device housing; a sealed cavity mounted on the upper surface of the bottom plate of the bonding device housing; a vacuum pump disposed on the left side of the sealed cavity; the outlet end of the vacuum pump communicating with the inner cavity of the sealed cavity; the vacuum pump mounted on the upper surface of the bottom plate of the bonding device housing; an extrusion plate disposed above the sealed cavity; a hydraulic telescopic rod mounted on the lower surface of the top plate of the bonding device housing; the output end of the hydraulic telescopic rod connected to the upper surface of the extrusion plate; and a pressure control unit mounted on the surface of the hydraulic telescopic rod. A pretreatment box is installed on the right side of the inner cavity of the bonding device housing. A plasma generator is installed inside the pretreatment box. A power controller and a time controller are installed on the surface of the pretreatment box. A motor is installed on the inner wall of the bonding device housing. A guide rod is installed at the rotor output end of the motor. An adjustment block is screwed onto the surface of the guide rod. A gradient curing lamp is installed on the surface of the adjustment block. A light intensity adjuster is installed on the left side of the front of the gradient curing lamp. A timer is installed on the right side of the front of the gradient curing lamp. A curing energy controller is installed on the upper surface of the gradient curing lamp.

[0005] Preferably, an air pump is installed at the air outlet of the pretreatment box, and an air inlet pipe is installed at the air outlet of the air pump. The air outlet of the air inlet pipe is connected to the inner cavity of the sealed cavity. The plasma generator processes a mixture of argon and oxygen, which can react with oil stains, impurities, etc. on the surface of the membrane material, thereby removing these pollutants and improving the cleanliness and activity of the membrane material surface. After starting, the air pump draws the treated gas from the pretreatment box through the air outlet, and the gas enters the air inlet pipe through the air outlet of the air pump. The gas is then injected into the sealed cavity from the air outlet of the air inlet pipe.

[0006] Preferably, the air outlet end of the sealed cavity is equipped with an air outlet pipe, the air outlet end of the air outlet pipe is connected to the air inlet end of the pretreatment box, and a valve is installed on the surface of the air outlet pipe. Opening the valve can discharge the air in the sealed cavity. After the mixed gas fills the sealed cavity, the air outlet pipe is closed, so that the mixed gas can react with oil stains, impurities and other contaminants on the surface of the membrane material, thereby removing these contaminants.

[0007] Preferably, a slider is installed at the bottom of the adjusting block, and a slide rail is installed in the inner cavity of the fitting device housing at a position corresponding to the slider. The slider is inserted into the interior of the slide rail, so that the adjusting block can move linearly.

[0008] Preferably, a limiting block is installed at the bottom of the gradient curing lamp, and a limiting track is installed on the back of the housing of the bonding device. The limiting block is embedded in the inner cavity of the limiting track, so that the gradient curing lamp is not easily deviated when it moves.

[0009] Preferably, the pressure control unit includes a pressure sensor and a pressure controller, both installed inside the pressure control unit. When the pressure sensor is activated, it senses the pressure within the pressure control unit or in associated systems. Through its internal sensing mechanism, it converts pressure information into an electrical signal or other recognizable signal form, transmitting the detected pressure signal to the pressure controller. Upon receiving the signal, the pressure controller compares and analyzes it against preset pressure parameters. If the detected pressure value is within the preset range, the pressure controller performs no additional operation, and the system maintains its current state. If the detected pressure value exceeds the preset range, the pressure controller activates corresponding control strategies. For example, if the pressure is too high, the pressure controller may take measures to reduce the pressure, such as adjusting the opening of relevant valves to release some gas or liquid; if the pressure is too low, it may activate booster equipment or adjust other related equipment to increase the pressure.

[0010] An optical film bonding process for a MiniLED backlight module, based on the aforementioned optical film bonding apparatus for a MiniLED backlight module, includes the following steps:

[0011] S1: Preprocessing steps:

[0012] Place the optical film material in the pretreatment chamber, start the plasma generator, set the processing power to 180W-220W through the power controller, and set the processing time to 28-32 seconds through the time controller to perform plasma cleaning on the surface of the film material.

[0013] S2: Adhesive application steps:

[0014] The pretreated optical film is transferred to the surface of the MiniLED backlight module, and UV adhesive is applied with a thickness of 8-12μm and a viscosity of 400-600cps.

[0015] S3: Vacuum bonding step:

[0016] The sealed cavity is closed, and the extrusion plate is driven to press down by the hydraulic telescopic rod. The pressure is controlled in stages. Pre-bonding is carried out at a pressure of 0.1MPa to eliminate macroscopic air bubbles. The pressure is then increased in stages from 0.3MPa to 0.5MPa, and the vacuum pump is started simultaneously to reduce the vacuum in the cavity to 10⁻²Pa.

[0017] S4: Gradient curing step:

[0018] Start the motor to drive the guide rod and move the adjusting block, so that the gradient curing lamp moves along the slide rail to above the bonding area. First curing: Set the UV light intensity to 50%-70% using the light intensity regulator and control the irradiation time to 10-15 seconds using the timer. Second curing: Adjust the light intensity regulator to 100% intensity, set the curing energy controller to a total energy of 800-1200mJ / cm², and continue for 20-30 seconds to complete the final curing.

[0019] Preferably, the pressure of the extrusion plate is adjusted to 0.1-0.3MPa in the initial pressing stage and maintained for 10-20 seconds to remove macroscopic bubbles. Due to the application of a certain pressure, the macroscopic bubbles in the film material are squeezed out under the pressure. Under the pressure, the gas inside the macroscopic bubbles is compressed and the volume is reduced, thereby squeezing out the air between the MiniLED backlight module film materials.

[0020] Preferably, in the final pressure stage of the extrusion plate, the pressure is linearly increased to 0.5-1.0 MPa and maintained for 30-60 seconds to achieve bubble-free sealing. The pressurization equipment is activated, causing the pressure of the extrusion plate to increase linearly from the pressure value after the initial pressure stage. Here, linear pressurization means that the pressure increases uniformly over time until it reaches the final pressure range of 0.5-1.0 MPa. During the pressurization process, the pressurization equipment operates according to a preset linear pressurization program to ensure that the pressure rises stably and uniformly, avoiding sudden pressure changes that could adversely affect the MiniLED backlight module. Once the pressure reaches the range of 0.5-1.0 MPa, this pressure is maintained. Under the action of higher pressure, the MiniLED backlight module further achieves sealing, further eliminating any remaining micro-bubbles inside, thereby achieving a bubble-free sealing state.

[0021] Preferably, the pressure control unit, power controller, time controller, light intensity regulator, timer, and curing energy controller precisely control key process parameters such as bonding pressure, plasma cleaning parameters, light intensity, and curing time. The pressure control unit monitors the pressure during the bonding process in real time through its internal pressure sensor and pressure controller. The power controller is responsible for power control during the plasma cleaning process. It adjusts the power output of the plasma generator according to preset plasma cleaning power parameters. If the actual power is lower than the preset value, the power controller increases the power supply; if the actual power is higher than the preset value, it decreases the power supply to ensure that the power of the plasma cleaning process remains at a precise set value. The time controller precisely controls the time of the plasma cleaning process. It starts timing from the beginning of the plasma cleaning process and sends a signal to stop the plasma cleaning process when the preset processing time is reached. The light intensity regulator is used to control the light intensity. It changes the light intensity by adjusting the current, voltage, or other optical components of the light source. When the light intensity is lower than a preset value, the light intensity regulator increases the output power of the light source or adjusts the optical components to enhance the light intensity; conversely, when the light intensity is higher than the preset value, it reduces the output power of the light source or adjusts the optical components to weaken the light intensity, thus precisely controlling the light intensity within the set range. The timer starts counting from the beginning of the curing process and sends a signal when the preset curing time is reached. During the curing process, the curing energy controller precisely controls the energy during curing based on the preset curing energy requirements, combined with the timer signal and factors such as light intensity. For example, if the light intensity changes during curing, the curing energy controller will adjust the curing time or other relevant parameters to ensure that the total curing energy meets the preset requirements.

[0022] In summary, compared with the prior art, the present invention provides an optical film bonding device and bonding process for MiniLED backlight modules, which has the following beneficial effects:

[0023] 1. The plasma generator added in this invention pre-treats the membrane material. Plasma pre-treatment can clean the surface of the membrane material, improve the activity of the membrane material surface, and help the adhesive to adhere better. It reduces the reliance on high temperature heating to improve the adhesion of the adhesive. At the same time, a pressure control unit is installed on the surface of the hydraulic telescopic rod. During the bonding process, a good bonding effect can be achieved by precisely controlling the pressure of the hydraulic telescopic rod. This precise pressure control does not require excessive reliance on high temperature to promote the bonding of the membrane material. Moreover, the gradient curing lamp adopts a gradient curing method during the curing process, which can cure the adhesive layer more gently. This prevents the membrane material from warping due to the difference in the coefficient of thermal expansion caused by rapid temperature changes. At the same time, it avoids the problem of bubbles generated by the evaporation of adhesive due to high temperature.

[0024] 2. This invention uses a plasma generator to perform plasma cleaning on the membrane surface. The power controller is set to a processing power of 180W-220W, and the time controller is set to a processing time of 28-32 seconds. This pretreatment improves the microstructure of the membrane surface and enhances its flatness. Even in vacuum environments where membrane flatness is critical, the pretreated membrane can better adapt to the lamination process under vacuum conditions. The pretreated membrane surface is cleaner and flatter, allowing for more uniform bonding with the MiniLED backlight module in subsequent adhesive coating, vacuum lamination, and curing steps. This reduces bonding problems caused by unevenness in the membrane itself, contributing to improved yield. In the gradient curing step, precise curing control is achieved through a light intensity regulator, timer, and curing energy controller. For the initial curing, the UV light intensity is set to 50%-70%, and the irradiation time is 10-15 seconds. For the second curing, the light intensity regulator is adjusted to 100% intensity, and the curing energy controller is set to a total energy of 800-1200 mJ / cm², lasting for 20-30 seconds to complete the final curing. This precise curing control ensures the adhesive layer cures effectively while avoiding over-curing or uneven curing that could affect the film's flatness, further improving yield. Simultaneously, the use of mechanical, staged pressure control ensures a tight bond between the film and the MiniLED backlight module in a vacuum environment, allowing air to escape during pressure application, thus saving on equipment costs. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the present invention.

[0026] Figure 2 This is a schematic diagram of the installation structure of the extrusion plate of the present invention.

[0027] Figure 3 This is a schematic diagram of the pretreatment box of the present invention.

[0028] Figure 4This is a schematic diagram of the gradient curing lamp of the present invention.

[0029] Figure 5 This is a flowchart of the present invention.

[0030] In the diagram: 1. Bonding device housing; 2. Sealed cavity; 3. Vacuum pump; 4. Extrusion plate; 5. Hydraulic telescopic rod; 51. Pressure control unit; 6. Pretreatment box; 61. Plasma generator; 62. Power controller; 63. Time controller; 7. Motor; 8. Guide rod; 9. Adjusting block; 10. Gradient curing lamp; 101. Light intensity adjuster; 102. Timer; 103. Curing energy controller; 11. Air pump; 12. Air inlet pipe; 13. Air outlet pipe; 14. Valve; 15. Slider; 16. Slide rail; 17. Limiting block; 18. Limiting track. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] This invention provides the following technical solution: an optical film bonding device for a MiniLED backlight module. (See also...) Figure 1 It includes: a bonding device housing 1, and a sealing cavity 2 mounted on the upper surface of the base plate of the bonding device housing 1. Please refer to [link / reference]. Figure 3 A vacuum pump 3 is located on the left side of the sealed cavity 2. The outlet of the vacuum pump 3 communicates with the inner cavity of the sealed cavity 2. The vacuum pump 3 is mounted on the upper surface of the base plate of the bonding device housing 1. Please refer to [link / reference]. Figure 1 A compression plate 4 is provided above the sealed cavity 2. Please refer to [link / reference]. Figure 2 A hydraulic telescopic rod 5 is installed on the lower surface of the top plate of the bonding device housing 1. The output end of the hydraulic telescopic rod 5 is connected to the upper surface of the extrusion plate 4. A pressure control unit 51 is installed on the surface of the hydraulic telescopic rod 5. Please refer to [link / reference]. Figure 3 A pretreatment box 6 is installed on the right side of the inner cavity of the bonding device housing 1. A plasma generator 61 is installed inside the pretreatment box 6. A power controller 62 and a time controller 63 are also installed on the surface of the pretreatment box 6. Please refer to [link / reference]. Figure 1 A motor 7 is installed on the inner wall of the housing 1 of the bonding device. Please refer to [link / reference]. Figure 4A guide rod 8 is installed at the rotor output end of motor 7. An adjustment block 9 is screwed onto the surface of the guide rod 8. A gradient curing lamp 10 is installed on the surface of the adjustment block 9. A light intensity adjuster 101 is installed on the left side of the front of the gradient curing lamp 10. A timer 102 is installed on the right side of the front of the gradient curing lamp 10. A curing energy controller 103 is installed on the upper surface of the gradient curing lamp 10.

[0033] Plasma generator 61 is used to pre-treat the membrane material. Plasma pre-treatment can clean the surface of the membrane material, improve its activity, and help the adhesive to adhere better. This reduces the reliance on high temperature heating to improve adhesive adhesion. At the same time, a pressure control unit 51 is installed on the surface of the hydraulic telescopic rod 5. During the bonding process, a good bonding effect can be achieved by precisely controlling the pressure of the hydraulic telescopic rod 5. This precise pressure control does not require excessive reliance on high temperature to promote membrane bonding. Furthermore, the gradient curing lamp 10 adopts a gradient curing method during the curing process, which can cure the adhesive layer more gently. This prevents the membrane material from warping due to differences in the coefficient of thermal expansion caused by rapid temperature changes, and also avoids the problem of bubbles generated by adhesive evaporation due to high temperature.

[0034] The power controller 62 and time controller 63 are initialized, setting the working power and processing time of the plasma generator 61 in the pretreatment chamber 6. The plasma generator 61 is then started to perform plasma cleaning treatment on the optical film of the MiniLED backlight module. During the process, the power controller 62 monitors the power in real time. If the actual power does not match the preset power, it is adjusted in time to maintain the set power. The time controller 63 simultaneously keeps track of the time. When the preset time is reached, the operation of the plasma generator 61 is stopped, and the vacuum pump 3 is started to extract the air from the sealed cavity 2, making the interior of the sealed cavity 2 reach a certain vacuum level. The outlet of the vacuum pump 3 continuously discharges the extracted gas to ensure that the environment inside the sealed cavity 2 meets the subsequent bonding requirements. The height of the extrusion plate 4 is adjusted by the hydraulic telescopic rod 5. The pressure control unit 51 monitors and controls the output pressure of the hydraulic telescopic rod 5 to ensure that the pressure of the hydraulic telescopic rod 5 is within a safe and appropriate range during the adjustment process. According to the set pressure value, the hydraulic telescopic rod 5 slowly pushes the extrusion plate 4 downward to bond the pretreated optical film onto the MiniLED backlight module. During this process, the pressure control unit 51 continuously monitors the pressure. When the pressure deviates from the preset bonding pressure range, it promptly adjusts the extension of the hydraulic telescopic rod 5 to maintain a suitable bonding pressure. The rotor of the motor 7 is then activated, driving the guide rod 8 to rotate. The adjustment block 9, screwed onto the surface of the guide rod 8, moves up and down with the rotation of the guide rod 8, thereby adjusting the height position of the gradient curing lamp 10 to a suitable position for curing the bonded optical film and MiniLED backlight module. The light intensity regulator 101, timer 102, and curing energy controller 103 are initialized, setting parameters such as the light intensity, curing time, and curing energy of the gradient curing lamp 10. The gradient curing lamp 10 is then activated to cure the bonded optical film and MiniLED backlight module. During the curing process, the light intensity regulator 101 monitors the light intensity in real time. If the light intensity deviates from the preset value, it promptly adjusts the output power of the gradient curing lamp 10 to maintain the set light intensity. The timer 102 keeps time, and when the preset curing time is reached, the gradient curing lamp 10 stops operating. The curing energy controller 103 ensures that the total curing energy during the curing process meets the preset requirements, and may be adjusted according to the actual situation of light intensity and curing time.

[0035] Please see Figure 3An air pump 11 is installed at the air outlet of the pretreatment box 6. An air inlet pipe 12 is installed at the air outlet of the air pump 11. The air outlet of the air inlet pipe 12 is connected to the inner cavity of the sealed cavity 2. The plasma generator 61 processes a mixture of argon and oxygen gas, which can react with oil stains, impurities and other contaminants on the surface of the membrane material, thereby removing these contaminants and improving the cleanliness and activity of the membrane material surface. After starting, the air pump 11 draws the processed gas in the box through the air outlet of the pretreatment box 6 and enters the air inlet pipe 12 through the air outlet of the air pump 11. The gas will be injected into the sealed cavity 2 from the air outlet of the air inlet pipe 12.

[0036] An air outlet pipe 13 is installed at the air outlet end of the sealed cavity 2. The air outlet end of the air outlet pipe 13 is connected to the air inlet end of the pretreatment box 6. A valve 14 is installed on the surface of the air outlet pipe 13. Opening the valve 14 can discharge the air in the sealed cavity 2. After the mixed gas fills the sealed cavity 2, the air outlet pipe 13 is closed, so that the mixed gas can react with oil stains, impurities and other contaminants on the surface of the membrane material, thereby removing these contaminants.

[0037] Please see Figure 4 A slider 15 is installed at the bottom of the adjusting block 9. A slide rail 16 is installed in the inner cavity of the fitting device housing 1 at the position corresponding to the slider 15. The slider 15 is inserted into the interior of the slide rail 16, so that the adjusting block 9 can move linearly.

[0038] A limiting block 17 is installed at the bottom of the gradient curing lamp 10, and a limiting track 18 is installed on the back of the bonding device housing 1. The limiting block 17 is embedded in the inner cavity of the limiting track 18, so that the gradient curing lamp 10 is not easy to deviate when it moves.

[0039] Please see Figure 2 The pressure control unit 51 includes a pressure sensor and a pressure controller, both installed inside the pressure control unit 51. When the pressure sensor is activated, it senses the pressure within the pressure control unit 51 or in associated systems. Through its internal sensing mechanism, it converts pressure information into an electrical signal or other recognizable signal form, transmitting the detected pressure signal to the pressure controller. Upon receiving the signal, the pressure controller compares and analyzes it against preset pressure parameters. If the detected pressure value is within the preset range, the pressure controller performs no additional operation, and the system maintains its current state. If the detected pressure value exceeds the preset range, the pressure controller activates corresponding control strategies. For example, if the pressure is too high, the pressure controller may take measures to reduce the pressure, such as adjusting the opening of the relevant valve 14 to release some gas or liquid; if the pressure is too low, it may activate a booster device or adjust other related equipment to increase the pressure.

[0040] Please see Figure 5An optical film bonding process for a MiniLED backlight module, based on the aforementioned optical film bonding apparatus for a MiniLED backlight module, includes the following steps:

[0041] S1: Preprocessing steps:

[0042] Place the optical film material in the pretreatment box 6, start the plasma generator 61, set the processing power to 180W-220W through the power controller 62, and set the processing time to 28-32 seconds through the time controller 63 to perform plasma cleaning on the surface of the film material.

[0043] S2: Adhesive application steps:

[0044] The pretreated optical film is transferred to the surface of the MiniLED backlight module, and UV adhesive is applied with a thickness of 8-12μm and a viscosity of 400-600cps.

[0045] S3: Vacuum bonding step:

[0046] The sealed cavity 2 is closed, and the extrusion plate 4 is driven to press down by the hydraulic telescopic rod 5. The pressure is controlled in stages. Pre-bonding is carried out at a pressure of 0.1MPa to eliminate macroscopic air bubbles. The pressure is then increased in stages from 0.3MPa to 0.5MPa. At the same time, the vacuum pump 3 is started to reduce the vacuum degree in the cavity to 10⁻²Pa.

[0047] S4: Gradient curing step:

[0048] The start motor 7 drives the guide rod 8 to move the adjusting block 9, so that the gradient curing lamp 10 moves along the slide rail 16 to the top of the bonding area. First curing: the UV light intensity is set to 50%-70% by the light intensity regulator 101, and the irradiation time is controlled to 10-15 seconds by the timer 102. Second curing: the light intensity regulator 101 is adjusted to 100% intensity, the curing energy controller 103 is set to the total energy of 800-1200mJ / cm², and the final curing is completed in 20-30 seconds.

[0049] In the initial pressing stage of the extrusion plate 4, the pressure is adjusted to 0.1-0.3MPa and lasted for 10-20 seconds to remove macroscopic bubbles. Due to the application of a certain pressure, the macroscopic bubbles in the film material are squeezed out under the pressure. Under the pressure, the gas inside the macroscopic bubbles is compressed and the volume is reduced, thereby squeezing out the air between the MiniLED backlight module film materials.

[0050] In the final pressure stage of the extrusion plate 4, the pressure is linearly increased to 0.5-1.0 MPa and maintained for 30-60 seconds to achieve bubble-free sealing. The pressurization equipment is activated, causing the pressure of the extrusion plate 4 to increase linearly from the pressure value after the initial pressure stage. Here, linear pressurization means that the pressure increases uniformly over time until it reaches the final pressure range of 0.5-1.0 MPa. During the pressurization process, the pressurization equipment operates according to a preset linear pressurization program to ensure a stable and uniform pressure increase, avoiding sudden pressure changes that could adversely affect the MiniLED backlight module. Once the pressure reaches the 0.5-1.0 MPa range, this pressure is maintained. Under the action of higher pressure, the film material further achieves sealing, further eliminating any tiny air bubbles that may remain inside the film material, thus achieving a bubble-free sealing state.

[0051] The pressure control unit 51, power controller 62, time controller 63, light intensity regulator 101, timer 102, and curing energy controller 103 precisely control key process parameters such as bonding pressure, plasma cleaning parameters, light intensity, and curing time. The pressure control unit 51 monitors the pressure during bonding in real time through its internal pressure sensor and pressure controller. The power controller 62 controls the power during plasma cleaning; it adjusts the power output of the plasma generator 61 according to preset plasma cleaning power parameters. If the actual power is lower than the preset value, the power controller 62 increases the power supply; if the actual power is higher than the preset value, it decreases the power supply to ensure the plasma cleaning power remains at a precise set value. The time controller 63 precisely controls the plasma cleaning time. It starts timing from the beginning of the plasma cleaning process and sends a signal to stop the process when the preset processing time is reached. The light intensity regulator 101 controls the light intensity. It changes the light intensity by adjusting the current, voltage, or other optical components of the light source. When the light intensity is lower than a preset value, the light intensity regulator 101 increases the output power of the light source or adjusts the optical components to enhance the light intensity; conversely, when the light intensity is higher than the preset value, it reduces the output power of the light source or adjusts the optical components to weaken the light intensity, thereby precisely controlling the light intensity within the set range. The timer 102 starts timing from the beginning of the curing process and sends a signal when the preset curing time is reached. During the curing process, the curing energy controller 103, based on the preset curing energy requirements, combines the time signal from the timer 102 with factors such as the light intensity to precisely control the energy during the curing process. For example, if the light intensity changes during the curing process, the curing energy controller 103 will adjust the curing time or other related parameters to ensure that the total curing energy meets the preset requirements.

[0052] First, the optical film material is carefully placed inside the pretreatment chamber 6. Then, the power controller 62 is operated to set the processing power of the plasma generator 61 to within the range of 180W-220W. Next, the processing time is set to 28-32 seconds using the time controller 63, and the plasma generator 61 is started. The plasma interacts with the surface of the optical film material, removing contaminants, organic matter, and other impurities from the film surface, thereby cleaning the film surface and improving the quality of subsequent bonding. The pretreated optical film material is transferred from the pretreatment chamber 6 to the surface of the MiniLED backlight module. A UV adhesive with a specific viscosity of 400-600cps is prepared and applied to the surface of the MiniLED backlight module, ensuring that the coating thickness is uniform and within the range of 8-12μm. The sealed cavity 2 is closed to form a relatively closed space, creating conditions for subsequent vacuum bonding. The extrusion plate 4 is driven down by the hydraulic telescopic rod 5, and the pressure is controlled at 0.1MPa for pre-bonding in the initial stage. In this process, lower pressure helps to eliminate macroscopic air bubbles between the optical film materials. Then, the film materials are pressurized in stages in the order of 0.3MPa→0.5MPa to make the optical film materials adhere more tightly. At the same time, vacuum pump 3 is started to reduce the vacuum degree in the sealed cavity to 10⁻²Pa. In a vacuum environment, it helps to further eliminate air bubbles during the bonding process and improve the bonding quality. The motor 7 is started to drive the guide rod 8 to rotate. The rotation of the guide rod 8 drives the adjusting block 9 to move, so that the gradient curing lamp 10 is moved along the slide rail 16 to the top of the bonding area to prepare for the curing operation. The UV light intensity is set to 50%-70% by the light intensity regulator 101, and then the gradient curing lamp 10 is started. The timer 102 starts timing and controls the irradiation time of the gradient curing lamp 10 to be between 10-15 seconds to initially cure the optical film. The light intensity regulator 101 is adjusted to increase the UV light intensity to 100%. The curing energy controller 103 is used to set the total energy to 800-1200mJ / cm², so as to bond the optical film.

[0053] Plasma cleaning is performed on the membrane surface using a plasma generator 61. The power controller 62 is set to a processing power of 180W-220W, and the time controller 63 is set to a processing time of 28-32 seconds. This pretreatment improves the microstructure of the membrane surface and enhances its flatness. Even in vacuum environments where membrane flatness is critical, the pretreated membrane can better adapt to the lamination process under vacuum conditions. The pretreated membrane surface is cleaner and flatter, allowing for more uniform bonding with the MiniLED backlight module in subsequent adhesive coating, vacuum lamination, and curing steps. This reduces bonding problems caused by unevenness in the membrane itself, contributing to improved yield. In the gradient curing step, precise curing control is achieved through a light intensity regulator 101, a timer 102, and a curing energy controller 103. During the initial curing, the UV light intensity is set to 50%-70%, and the irradiation time is 10-15 seconds. During the second curing, the light intensity regulator 101 is adjusted to 100%, and the curing energy controller 103 is set to a total energy of 800-1200 mJ / cm², with a duration of 20-30 seconds to complete the final curing. This precise curing control ensures the effective curing of the adhesive layer while avoiding the impact of over-curing or uneven curing on the flatness of the film material, further improving the yield. Simultaneously, the use of a mechanical, staged pressure control method ensures that the film material is tightly bonded to the MiniLED backlight module in a vacuum environment, and air is expelled during pressure application, saving equipment costs.

[0054] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0055] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An optical film bonding device for a MiniLED backlight module, characterized in that, include: The bonding device housing (1) has a sealing cavity (2) installed on the upper surface of its base plate. A vacuum pump (3) is provided on the left side of the sealing cavity (2). The outlet of the vacuum pump (3) is connected to the inner cavity of the sealing cavity (2). The vacuum pump (3) is installed on the upper surface of the base plate of the bonding device housing (1). An extrusion plate (4) is provided above the sealing cavity (2). A hydraulic telescopic rod (5) is installed on the lower surface of the top plate of the bonding device housing (1). The output end of the hydraulic telescopic rod (5) is connected to the upper surface of the extrusion plate (4). A pressure control unit (51) is installed on the surface of the hydraulic telescopic rod (5). A pretreatment box (6) is installed on the right side of the inner cavity of the bonding device housing (1). A plasma generator (61) is installed inside the box (6). A power controller (62) is installed on the surface of the pretreatment box (6). A time controller (63) is also installed on the surface of the pretreatment box (6). A motor (7) is installed on the inner wall of the bonding device housing (1). A guide rod (8) is installed at the rotor output end of the motor (7). An adjustment block (9) is screwed onto the surface of the guide rod (8). A gradient curing lamp (10) is installed on the surface of the adjustment block (9). A light intensity adjuster (101) is installed on the left side of the front of the gradient curing lamp (10). A timer (102) is installed on the right side of the front of the gradient curing lamp (10). A curing energy controller (103) is installed on the upper surface of the gradient curing lamp (10).

2. The optical film bonding device for a MiniLED backlight module according to claim 1, characterized in that: An air pump (11) is installed at the air outlet of the pretreatment box (6), and an air inlet pipe (12) is installed at the air outlet end of the air pump (11). The air outlet end of the air inlet pipe (12) is connected to the inner cavity of the sealed cavity (2).

3. The optical film bonding device for a MiniLED backlight module according to claim 1, characterized in that: The air outlet end of the sealed cavity (2) is equipped with an air outlet pipe (13), the air outlet end of the air outlet pipe (13) is connected to the air inlet end of the pretreatment box (6), and a valve (14) is installed on the surface of the air outlet pipe (13).

4. The optical film bonding device for a MiniLED backlight module according to claim 1, characterized in that: The bottom of the adjusting block (9) is equipped with a slider (15), and the inner cavity of the fitting device housing (1) is equipped with a slide rail (16) corresponding to the slider (15), and the slider (15) is inserted into the slide rail (16).

5. The optical film bonding device for a MiniLED backlight module according to claim 1, characterized in that: A limiting block (17) is installed at the bottom of the gradient curing lamp (10), and a limiting track (18) is installed on the back of the bonding device housing (1). The limiting block (17) is embedded in the inner cavity of the limiting track (18).

6. The optical film bonding device for a MiniLED backlight module according to claim 1, characterized in that: The pressure control unit (51) includes a pressure sensor and a pressure controller, both of which are installed inside the pressure control unit (51).

7. An optical film bonding process for a MiniLED backlight module, based on the optical film bonding apparatus for a MiniLED backlight module according to any one of claims 1-6, characterized in that, Includes the following steps: S1: Preprocessing steps: Place the optical film material in the pretreatment box (6), start the plasma generator (61), set the processing power to 180W-220W through the power controller (62), and set the processing time to 28-32 seconds through the time controller (63) to perform plasma cleaning on the surface of the film material. S2: Adhesive application steps: The pretreated optical film is transferred to the surface of the MiniLED backlight module and coated with UV adhesive. The coating thickness is 8-12μm and the adhesive viscosity is 400-600cps. S3: Vacuum bonding step: Close the sealed cavity (2), drive the extrusion plate (4) to press down through the hydraulic telescopic rod (5), control the pressure in stages, use 0.1MPa pressure for pre-bonding to eliminate macroscopic bubbles, and pressurize in stages from 0.3MPa to 0.5MPa, while simultaneously starting the vacuum pump (3) to reduce the vacuum level in the cavity to 10⁻²Pa. S4: Gradient curing step: Start the motor (7) to drive the guide rod (8) to move the adjustment block (9) so that the gradient curing lamp (10) moves along the slide rail (16) to the top of the bonding area for the first curing: set the UV light intensity to 50%-70% by the light intensity adjuster (101) and control the irradiation time to 10-15 seconds by the timer (102); Secondary curing: Adjust the light intensity regulator (101) to 100% intensity, set the curing energy controller (103) to a total energy of 800-1200mJ / cm², and continue for 20-30 seconds to complete the final curing.

8. The optical film bonding process for a MiniLED backlight module according to claim 7, characterized in that: The initial pressure stage of the extrusion plate (4) is adjusted to 0.1-0.3 MPa and lasts for 10-20 seconds to remove macroscopic bubbles.

9. The optical film bonding process for a MiniLED backlight module according to claim 7, characterized in that: The final pressure stage of the extrusion plate (4) will linearly increase the pressure to 0.5-1.0 MPa and continue for 30-60 seconds to achieve bubble-free sealing.

10. The optical film bonding process for a MiniLED backlight module according to claim 7, characterized in that: The pressure control unit (51), power controller (62), time controller (63), light intensity regulator (101), timer (102), and curing energy controller (103) components control key process parameters such as bonding pressure, plasma cleaning parameters, light intensity, and curing time.

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