High-density microwire light source array structure, control method and application

Abstract

This invention belongs to the field of semiconductor optoelectronic device technology, specifically relating to a high-density micron-level line light source array structure, control method, and application. The line light source array includes a micro-light-emitting unit array and an integrated driving system. The control method includes data input and analysis, pixel-level light control, beam collimation, dynamic temperature control, and synchronous scanning, and also includes a galvanometer system. This invention integrates customizable 1-micron-level light-emitting units, on-chip integrated metasurface beam collimation technology, and a CMOS integrated driving and heat dissipation scheme optimized for high density. This line light source array successfully solves key challenges such as micron-level resolution light source manufacturing, efficient beam collimation with a large divergence angle, flexible wavelength adaptation, high-density heat dissipation, and ultra-fine independent control. It features micron-level resolution, a near-parallel high-quality beam, customizable wavelength output, stable thermal performance, and high-speed programmability, providing a core light source for high-precision, high-efficiency, and high-flexibility direct-write lithography and 3D printing.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor optoelectronic device technology, specifically relating to a high-density micron-line light source array structure with beam collimation, control method and application. Background Technology

[0002] Currently, precision lithography and 3D printing technologies are developing towards higher resolution, higher speed, and more flexible multi-material, multi-wavelength processing. However, as a core light source component, existing technologies face significant bottlenecks: 1. Resolution and light source size limitations: Achieving micrometer-level linewidths requires the light source itself to have addressable units on the micrometer or submicrometer scale. Traditional laser diodes or LED arrays typically have light-emitting units on the order of tens of micrometers, making it difficult to meet the requirements of ultra-high resolution. While existing microlight sources can be miniaturized, they face bottlenecks in high-density integration (especially at the 1-micrometer scale) and beam control.

[0003] 2. The beam divergence angle is too large: The emitted light from micro-LEDs and other micro-light-emitting units follows a Lambertian distribution and has a large divergence angle (typical half-angle width > 60°). This leads to: Low light energy utilization: Most of the light cannot be effectively coupled into the subsequent optical system.

[0004] Severe crosstalk: The light rays from adjacent cells are very likely to overlap and interfere with each other, reducing imaging contrast.

[0005] The optical system becomes more complex: additional complex collimating optical elements (such as microlens arrays and collimating lens groups) are required to focus the beam, which increases the system size, cost and assembly difficulty, and requires stringent alignment accuracy.

[0006] 3. Insufficient wavelength flexibility: Specific applications (such as photoresist sensitization and multi-material 3D printing) require light sources with specific wavelengths. Existing light sources often have fixed wavelengths, and changing the wavelength requires replacing the entire light source module, which lacks flexibility and economy.

[0007] 4. High-density integrated heat dissipation challenge: When the size of the light-emitting unit shrinks to the micrometer level and is integrated at high density, the heat power density increases dramatically. Traditional heat dissipation solutions struggle to effectively control chip temperature rise, leading to decreased luminous efficiency, wavelength drift, and shortened device lifespan.

[0008] 5. Driving and control complexity: High-speed, independent, and precise addressing and illumination of tens of thousands of micrometer-sized light-emitting units requires highly integrated and low-power driving circuits. Existing solutions either lack sufficient integration or are difficult to match the physical size and electrical requirements of micrometer-sized units.

[0009] Therefore, it is necessary to develop a new type of line light source that combines micron-level addressable cell size, customizable output wavelength, extremely low beam divergence angle, high heat dissipation capability, and highly integrated CMOS driver.

[0010] In addition, existing line scanning systems still face the following key technical challenges in the beam scanning stage of the galvanometer system: Redundant Dual-Axis Scanning: Many existing line scanning schemes still use the traditional point scanning X and Y dual-axis galvanometer system. This fails to fully utilize the illumination already achieved by the line light source in the X direction, resulting in functional redundancy in the X-axis. This not only increases unnecessary system complexity, size, weight, and cost, but also introduces additional potential error sources (such as multi-axis coupling errors) and thermal management burdens, limiting the potential for increasing scan speed.

[0011] The challenge of pixel-level synchronization: The core of line scanning lies in precise pixel-level synchronization. Each or each group of micro-light-emitting units (corresponding to a "pixel") on the line light source must be lit at a precise moment, while the galvanometer must move precisely to the target position corresponding to that pixel in the Y direction.

[0012] Any timing delay (control delay, communication delay, mechanical response delay) or positional error (insufficient galvanometer positioning accuracy, vibration) will cause the pixel to be misaligned on the workpiece (smear or blur), which will seriously affect the imaging resolution and edge sharpness.

[0013] Achieving high-precision, low-latency, real-time synchronous control across systems (light source drive and galvanometer drive) is a significant challenge in existing technologies. This is especially true when micrometer / submicrometer resolution is required, necessitating synchronization accuracy at the microsecond or even nanosecond level.

[0014] Stability and accuracy under high-speed scanning: High throughput requires the galvanometer to perform high-speed reciprocating scanning in the Y-axis direction. This places extremely high demands on the galvanometer's dynamic performance (response speed, bandwidth), mechanical stability (vibration resistance), thermal stability (low thermal deformation), and position feedback accuracy.

[0015] In this scenario, the galvanometer used for X-axis scanning in a traditional dual-axis system becomes a performance bottleneck and a source of error.

[0016] Misfits of focusing field lenses: Traditional field lenses (f-theta lenses) are designed for point light sources and square / circular fields of view. Circular / square fields of view cannot effectively cover the long, narrow beams (high aspect ratio, such as 100mm × 2mm) of a line light source, resulting in wasted aperture or a sharp decline in edge performance.

[0017] Insufficient X-direction performance: Excessive distortion in the long axis X direction causes non-linear positional shift of pixels at different X positions of the line light source on the workpiece, compromising graphic accuracy; uneven resolution (MTF) and degraded image quality in edge areas; uneven light intensity distribution.

[0018] Insufficient performance in the Y direction: Significant field curvature and astigmatism occur in the Y-direction of the scan, causing variations in the short-side height (Z) of the line beam at different Y positions, resulting in blurred edges, inconsistent linewidth, and image distortion. f-theta linearity may also deteriorate at the edges of elongated fields of view.

[0019] Consequences: Even if the light source and galvanometer are perfectly synchronized, an unsuitable field lens will severely degrade the final exposure resolution, positional accuracy, linewidth uniformity, and edge quality.

[0020] System integration complexity: Efficiently and compactly integrating light sources, especially complex multi-wavelength line light sources, color combining systems, scanning systems, focusing systems, field lenses, and the control systems that coordinate them, while ensuring overall accuracy and stability, is a major challenge in engineering implementation.

[0021] In summary, the existing technology suffers from three main defects: unnecessary redundancy in the dual-axis galvanometer structure, a lack of reliable pixel-level spatiotemporal synchronization mechanisms (particularly affecting beam combining and positioning accuracy), and a severe mismatch between the characteristics of the field lens and the line beam. These defects collectively limit the performance and reliability of line scanning technology in high-precision, high-efficiency exposure applications at the micron and submicron levels. Summary of the Invention

[0022] In view of the shortcomings of the prior art, one object of the present invention is to provide an ultra-high density, multi-wavelength integrated micro-light-emitting unit array structure with excellent optical performance, which is particularly suitable for fields requiring precise spatial light intensity control, such as high-resolution direct-write lithography and high-speed 3D printing. Another object of the present invention is to provide an application of a high-density micron-line light source array structure with beam collimation.

[0023] To achieve the above objectives, the present invention adopts the following technical solution: A high-density micron-line light source array structure includes a micro-light-emitting unit array and an integrated driving system; The micro-light-emitting unit array is a long strip array, employing m×n independently controllable Micro-LED units. The center-to-center spacing of the units is 1μm, and the effective size of a single micro-light-emitting unit is submicron and <1μm. It supports R / G / B / UV multi-wavelength configuration and wavelengths can be customized according to application requirements. The surface of the micro-light-emitting unit array is directly wafer-bonded to the optical metasurface layer. The integrated driving system includes a CMOS driving backplane, which is a silicon-based integrated circuit containing m×n independent driving units. Each independent driving unit corresponds one-to-one with a micro-light-emitting unit array. The CMOS driving backplane is copper-copper hybrid bonded to the lower layer of the micro-light-emitting unit array. The CMOS driving backplane is connected to the FPGA main control module via an LVDS interface. The FPGA main control module is connected to the galvanometer system via a DB9 interface. The CMOS driving backplane is bonded to the integrated heat dissipation substrate with thermally conductive silver paste.

[0024] The values ​​are m≥200, n≥2, and m:n≥50; preferably, m=16384 and n=4.

[0025] Explanation of the principles behind setting the values ​​and ratios of m and n: First, the working mode of a line light source is line scanning: an extremely thin light with high pixel density, in conjunction with a galvanometer, scans at high speed in the Y-axis direction to cover the entire working surface. Therefore, the physical form of the light source must be a "line" with a very large aspect ratio. m represents the long side direction: corresponding to the scanning direction. A large m value (≥200) ensures that there are enough independently addressable pixels in the scanning direction, which is the physical basis for achieving micron-level high resolution.

[0026] n represents the short side direction: defining the width of the "line". A very small value of n (≥2, usually 2-4) ensures that the physical size of the light source is extremely narrow in the non-scanning direction, thus projecting a clear "line" directly onto the workpiece, rather than a blurry "rectangular surface".

[0027] Second, setting m:n ≥ 50 is a quantitative representation of the above design concept and a lower limit of the preferred embodiment.

[0028] When the aspect ratio is less than 50 (e.g., 100×3, the ratio is approximately 33), it means that with the same total number of pixels, the width of the shorter side, n, is relatively large. This results in a weakening of the "line" feature, making it closer to a "narrow rectangle," which is detrimental to high-quality line scanning.

[0029] Therefore, "50" is the critical ratio that ensures all the core advantages of a line light source can still be clearly demonstrated at the lowest pixel scale (m=200).

[0030] The optical metasurface layer is a silicon dioxide film or silicon nitride film with a thickness of 0.55µm, an etched diameter of 100-300nm, a height of 200-800nm, and a spacing less than the emission wavelength.

[0031] The integrated heat dissipation substrate is a 2mm thick pure copper plate. The integrated heat dissipation substrate has an external heat dissipation device, which includes a water-cooled or high-speed centrifugal fan. The high-speed centrifugal fan has a wind speed >8m / s and a power <10W. A temperature sensor is embedded near the light-emitting unit array on the CMOS driving backplane. One temperature sensor is arranged for every 1024 units. The thermal conductivity of the thermally conductive silver paste on the CMOS driving backplane is ≥10W / m·K.

[0032] The main control FPGA module is a Xilinx Artix7 series, which includes a high-speed LVDS interface; the galvanometer system is a Y-axis scanning galvanometer with a scanning frequency ≥1kHz.

[0033] A method for controlling a high-density micron-line light source array structure includes the following steps: Step 1: Data Input and Parsing The host computer sends image data streams to the FPGA main control module via the GigE gigabit network port; The FPGA main control module splits the image data into 65,536 independent pixel signals and transmits them to the CMOS driver backplane through the LVDS interface; Step 2, Pixel-level light control: After receiving the signal, the CMOS driver backplane latches the data into the SRAM cache for each driver unit. Based on preset PWM parameters, a customized current is output to the corresponding MicroLED within <100ns; 65,536 micro-light-emitting units are lit up point by point according to the image; Step 3, beam collimation: The outgoing light from the Lambert-distributed MicroLED enters the optical metasurface layer; the nanopillar array converts light with a divergence angle > 60° into a collimated beam through spatial phase modulation based on gradient refractive index design. Step 4, Dynamic Temperature Control: A temperature sensor monitors the chip temperature in real time; the temperature signal is transmitted to the FPGA main control module via the IC bus; the FPGA main control module executes the PID algorithm: if the temperature is >40℃, the fan PWM duty cycle is increased; if the temperature is >60℃, the MicroLED drive current is reduced. Step 5, Synchronous Scan: The FPGA main control module generates galvanometer control signals: it outputs sawtooth wave analog voltage to the galvanometer driver according to the image line frequency; when the galvanometer reaches the start position of each line, it sends a TTL synchronization pulse to trigger CMOS backplane exposure.

[0034] In step 2, the preset PWM parameter resolution is 8 bits, and the output current is 0.10mA within <100ns.

[0035] In step 3, the divergence angle of the collimated beam after conversion is <10°.

[0036] In step 4, the sampling rate of the temperature sensor when monitoring the chip temperature in real time is 1kHz; the adjustment range of the fan PWM duty cycle is 0~100%.

[0037] In step 5, the image line frequency is 10kHz.

[0038] A galvanometer system comprising the aforementioned high-density micron-level line light source array structure, using the aforementioned line light source array structure as the light source, further includes a host computer, a central control unit, a high-density line light source module, a color combining system, a galvanometer body, a galvanometer drive controller, and a dedicated focusing field lens. The galvanometer body includes a reflecting mirror, a support bearing, a drive motor, and a high-precision position sensor. The galvanometer drive controller receives position commands, drives the motor to move, and reads feedback from the position sensor for closed-loop control. The galvanometer body is fixed on the system's optical platform, and its reflecting mirror surface is located in the optical path of the emitted beam from the color combining system or the monochromatic line light source. The galvanometer drive controller receives Y-axis position and velocity commands sent from the output terminal B of the central control unit. The galvanometer drive controller feeds back the real-time high-precision Y-axis position signal read by the high-precision position sensor to the central control unit through an analog output or a digital interface as an input for optional compensation.

[0039] The galvanometer body is a high-dynamic-performance galvanometer-type galvanometer, the reflecting mirror has a fused silica protective film, the drive motor is a moving coil or moving magnet type, and the high-precision position sensor is a photoelectric encoder or a capacitive displacement sensor.

[0040] The main components and their functions in the high-precision line scan exposure system are as follows: Host computer: Provides the image data stream to be exposed, containing two-dimensional pixel information, and system control commands including scanning speed, stroke, power, etc.

[0041] Central Control Unit: The core processing and coordination center, typically containing a high-performance microprocessor, such as a multi-core ARM Cortex-A series, FPGA, or DSP, along with supporting memory and communication interfaces. Input Terminal: Connects to a host computer via a high-speed data interface to receive image data streams and commands. Input Terminal: Connects to temperature sensors located at key positions such as the core of the line light source and near the galvanometer via analog / digital input ports to monitor system temperature. Output Terminal A: Connects to the CMOS driver backplane of the line light source via a high-speed, low-latency digital interface. Output Terminal B: Connects to the galvanometer driver controller via analog ±10V differential output and / or a digital communication interface.

[0042] High-density line light source module: Composition: Includes the aforementioned line light source array structure (such as 16384×4 independently controllable Micro-LED or similar light-emitting units, with a physical spacing of approximately 1µm), a CMOS driving backplane with integrated row and column driving circuits, an LED driver chip providing constant current driving, and a thermal management subsystem, such as a TEC semiconductor cooler and a microchannel cooling plate.

[0043] Signal terminal: The CMOS driver backplane receives the pixel illumination control signal sent by the output terminal A of the central control unit, including: row and column address, grayscale, and timing.

[0044] Driving end: The CMOS driving backplane controls the LED driving chip, and the driving chip outputs current to the corresponding micro light-emitting unit.

[0045] Thermal management end: The thermal management subsystem receives temperature adjustment commands from the central control unit based on feedback from temperature sensors.

[0046] Color mixing system: Composition: For multi-wavelength line light sources, such as R, G, and B, it includes corresponding nanopillar array homogenizing elements, high-NA cylindrical lens groups, and color combining prisms. It is an optical component with no direct electrical signal connection. Its light input end is optically coupled to the light output port of each line light source module, and its light output end is optically coupled to the incident light path of the galvanometer system.

[0047] The present invention can achieve the following significant and quantifiable technical effects: 1. Superior beam quality and ultra-high spatial resolution: Provides a light source based on 1-micron addressable cells, laying the physical foundation for generating patterns with micron-level linewidths / features.

[0048] 2. Minimal divergence angle: Metasurfaces compress the half-angle width of the outgoing beam from the typical >60° to <10°, approaching parallel light.

[0049] 3. High light energy utilization: The collimated beam is more easily coupled into the subsequent optical system, and the system light efficiency is improved by more than 30%.

[0050] 4. Low crosstalk: Optical crosstalk between adjacent units is reduced to <3%, significantly improving imaging contrast and edge sharpness.

[0051] 5. Flexible wavelength adaptation: It can provide specific customized wavelengths in the ultraviolet to infrared range according to application requirements, adapting to diverse materials and processes.

[0052] 6. Effective thermal control: Under typical operating conditions, the heat dissipation scheme described above can control the chip junction temperature rise to <30°C (relative to ambient temperature), ensuring stable and reliable light source performance.

[0053] 7. High-speed and precise control: The CMOS backplane supports independent addressing and modulation of each micron unit at the level of <100ns, meeting the requirements of high-speed scanning.

[0054] 8. System Simplification and Cost-Effectiveness: Eliminating the large and complex external collimating optical system significantly reduces the size and cost of the optical engine. Customizable wavelengths reduce reliance on multiple or tunable light sources. The simplified heat dissipation scheme facilitates implementation and maintenance.

[0055] 9. The galvanometer system offers the following advantages: It eliminates redundant X-axis scanning, focusing on optimizing the performance and synchronization control of the Y-axis galvanometer, achieving pixel-level matching with the emission timing of the line source; Single-axis scanning architecture: Using only a single Y-axis galvanometer simplifies the structure, reduces cost, size, and weight, minimizes potential error sources, and unlocks the potential for higher scanning speeds; Dedicated adaptive field lenses: Designed or selected focusing field lenses optimized for scanning long, narrow line beams, possessing key characteristics such as a rectangular field of view, ultra-low X-direction distortion and high MTF, strict Y-direction f-theta linearity, and ultra-low field curvature / astigmatism (maintaining constant line height sharpness), providing optical assurance for final image quality; Precise synchronization mechanism: Unified control source: The central control unit uniformly generates pixel illumination control signals for the line light sources (LEDs) (via a CMOS driver backplane) and scanning position / speed commands for the galvanometer. Timing coordination: Based on the image data stream from the host computer and preset scanning parameters (speed, travel), the control unit accurately calculates the illumination time for each line light source unit column (or area) and the target Y position the galvanometer needs to reach at the corresponding time, generating strictly synchronized control signals. Low-latency design: Employing high-speed communication interfaces (such as LVDS, EtherCAT) and real-time processing algorithms minimizes signal transmission and processing delays. Closed-loop feedback and compensation: Utilizing high-precision position sensors (such as photoelectric encoders) on the galvanometer to provide real-time feedback on the actual position, the control unit can perform dynamic compensation (such as fine-tuning the illumination timing or galvanometer commands) to counteract mechanical response delays, vibrations, and other disturbances. High-performance single-axis galvanometer design: Optimizing the galvanometer structure (such as lightweight lenses, high-rigidity flexible supports or bearings, high-performance voice coil / piezoelectric actuators) to meet the high-speed Y-axis scanning requirements, and integrating high-resolution position sensors to ensure high dynamic performance, positioning accuracy, and stability at high speeds. System-level integration: The interfaces and collaborative working relationships between the galvanometer system, the line light source (including the LED drive control system), the color combining system, the focusing field lens, and the central control unit are clearly defined, forming a highly efficient, compact, and high-precision line scan exposure execution core. Achieving beam-combining pixel alignment: Through the aforementioned synchronization mechanism, it is ensured that each "pixel" on the colored light synthesized by the color combining prism is reflected at a precise moment by the galvanometer precisely positioned at its corresponding Y-axis position, and ultimately precisely imaged onto the designated location on the workpiece by the field lens. For example, when the RGB micro-units in the Nth column of the line light source are synchronously triggered to emit light and combine into a specific color, the galvanometer must ensure that at the instant the beam reaches its mirror surface, its Y-axis position is precisely such that the reflected beam hits the Nth row of the workpiece at the current Y-coordinate position via the field lens. This spatiotemporal consistency across the light source, color combining, scanning, and focusing is key to achieving perfect pixel alignment. Attached Figure Description

[0056] Figure 1 This is a schematic diagram of the micro-luminescent unit array arrangement of the present invention.

[0057] Figure 2 This is a schematic diagram of the single-layer optical metasurface structure integrated on the light-emitting side of the micro-light-emitting unit of the present invention.

[0058] Figure 3 This is a phase comparison diagram before and after metasurface phase modulation.

[0059] Figure 4 This is a micro-light-emitting unit array supported by a silicon-based CMOS driving backplane.

[0060] Figure 5 This is a schematic diagram of the overall structure of the high-density micron-line light source array of the present invention.

[0061] Figure 6 A flowchart illustrating a control method for beam collimation using a high-density micron-line light source array structure.

[0062] Figure 7 This is a schematic diagram of the overall structure of a high-precision line scan exposure system - galvanometer system.

[0063] In the diagram: 1. Outer shell, 2. Back cover, 3. Front panel, 4. Heat sink, 5. Protective mesh, 6. Fan, 7. Copper studs, 8. Dustproof mesh, 9. Control board, 10. Micro-light-emitting unit array supported by silicon-based CMOS driver backplane. Detailed Implementation

[0064] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0065] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0066] Example 1 A high-density micron-line light source array structure includes a micro-light-emitting unit array and an integrated driving system; The micro-light-emitting unit array employs 16384 × 4 independently controllable Micro-LED units, with a center-to-center spacing of 1 μm. The effective size of each micro-light-emitting unit is sub-micron and <1 μm, supporting R / G / B / UV multi-wavelength configurations, and wavelengths can be customized according to application requirements. A schematic diagram of the arrangement is shown below. Figure 1 As shown; the surface of the micro-light-emitting unit array is directly wafer-bonded to the optical metasurface layer, and a schematic diagram of the single-layer optical metasurface structure is shown below. Figure 2 ; The integrated driving system includes a CMOS driving backplane, which is a silicon-based integrated circuit containing 65,536 independent driving units, each corresponding one-to-one with a micro-light-emitting unit array (MSI) unit. The CMOS driving backplane is copper-copper hybrid-bonded to the lower layer of the MSI array. A temperature sensor is embedded near the MSI array on the CMOS driving backplane. The CMOS driving backplane is connected to an FPGA main control module via an LVDS interface, and the FPGA main control module is connected to a galvanometer system via a DB9 interface. The integrated MSI array, supported by the silicon-based CMOS driving backplane, is as follows: Figure 4 As shown; The CMOS driver backplane is bonded to the integrated heat dissipation substrate by thermally conductive silver paste, and the integrated heat dissipation substrate has an external high-speed centrifugal fan. Figure 5 This is a schematic diagram of the overall structure of the high-density micron-line light source array of the present invention.

[0067] The optical metasurface layer is a silicon dioxide or silicon nitride film with a thickness of 0.55µm, an etched surface diameter of 200nm, a height of 500nm, and a subwavelength nanopillar array with a spacing less than the emission wavelength.

[0068] The integrated heat dissipation substrate is a 2mm thick pure copper plate, the high-speed centrifugal fan has a wind speed >8m / s and a power <10W, one temperature sensor is arranged for every 1024 units, and the thermal conductivity of the thermally conductive silver paste is ≥10W / m·K.

[0069] The main control FPGA module is a Xilinx Artix7 series, which includes a high-speed LVDS interface; the galvanometer system is a Y-axis scanning galvanometer with a scanning frequency ≥1kHz.

[0070] The calculation basis for the 50% increase in luminous efficacy: The total luminous efficacy of the system is determined by the product of the following three efficiencies: Total luminous efficacy = Collimation efficiency × Transmission efficiency × Coupling efficiency Comparison of the micro / nano structure scheme of this invention with the traditional microlens group scheme: Table 1. Comparison of the micro / nano structure scheme of this invention with the traditional microlens group scheme. .

[0071] Example 2 A method for controlling the high-density micron-line light source array structure described in Example 1, such as... Figure 6 As shown, it includes the following steps: Step 1: Data Input and Parsing The host computer sends image data streams to the FPGA via the GigE gigabit Ethernet port; The FPGA splits the image data into 65,536 independent pixel signals and transmits them to the CMOS backplane via the LVDS interface; Step 2, Pixel-level light control: After receiving the signal, the CMOS backplane latches the data into the SRAM cache for each drive unit; According to the preset PWM parameters, a customized current is output to the corresponding MicroLED within <100ns; 65536 1-micron light-emitting units are lit up point by point according to the image; in this embodiment, the preset PWM parameters have a resolution of 8 bits and output a customized current of 0.10mA within <100ns; Step 3, beam collimation: The outgoing light from the Lambertian-distributed MicroLED enters the metasurface layer; the nanopillar array converts light with a divergence angle >60° into a collimated beam through spatial phase modulation based on gradient refractive index design; the converted collimated beam has a divergence angle <10°; such as Figure 3 The image shows a phase comparison before and after metasurface phase modulation. Step 4, Dynamic Temperature Control: A temperature sensor monitors the chip temperature in real time; the temperature signal is transmitted to the FPGA via the IC bus; the FPGA executes a PID algorithm: if the temperature > 40℃, the fan PWM duty cycle is increased; if the temperature > 60℃, the MicroLED drive current is reduced; in this embodiment, the sampling rate of the temperature sensor when monitoring the chip temperature in real time is 1kHz; the adjustment range of the fan PWM duty cycle is 0~100%. Step 5, Synchronous Scan: The FPGA generates mirror control signals: it outputs a sawtooth wave analog voltage to the mirror driver based on the image line frequency; when the mirror reaches the start position of each line, it sends a TTL synchronization pulse to trigger CMOS backplane exposure. In this embodiment, the image line frequency is 10kHz.

[0072] Example 3 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1. The differences are as follows: the micro-light-emitting unit array adopts 200×4 independently controllable Micro-LED units, the CMOS driving backplane contains 800 independent driving units, and the surface etching diameter of the optical metasurface layer is 100nm and the height is 200nm.

[0073] Example 4 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1. The difference is that the micro-light-emitting unit array uses 200×2 independently controllable Micro-LED units, the CMOS driving backplane contains 400 independent driving units, and the surface etching diameter of the optical metasurface layer is 300nm and the height is 800nm.

[0074] Example 5 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1, except that the micro-light-emitting unit array uses 16384×2 independently controllable Micro-LED units, and the CMOS driving backplane contains 32768 independent driving units.

[0075] Example 6 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1. The difference is that the micro-light-emitting unit array uses 8192×4 independently controllable Micro-LED units, and the CMOS driving backplane contains 32768 independent driving units.

[0076] Example 7 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1, except that the micro-light-emitting unit array uses 8192×2 independently controllable Micro-LED units, and the CMOS driving backplane contains 16384 independent driving units.

[0077] Example 8 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1. The difference is that the micro-light-emitting unit array uses 4096×4 independently controllable Micro-LED units, and the CMOS driving backplane contains 16384 independent driving units.

[0078] Example 9 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1, except that the micro-light-emitting unit array uses 4096×2 independently controllable Micro-LED units, and the CMOS driving backplane contains 8192 independent driving units.

[0079] Example 10 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1, except that the micro-light-emitting unit array uses 2048×4 independently controllable Micro-LED units, and the CMOS driving backplane contains 8192 independent driving units.

[0080] Example 11 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1, except that the micro-light-emitting unit array uses 2048×2 independently controllable Micro-LED units, and the CMOS driving backplane contains 4096 independent driving units.

[0081] Example 12 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1. The difference is that the micro-light-emitting unit array uses 1024×4 independently controllable Micro-LED units, and the CMOS driving backplane contains 4096 independent driving units.

[0082] Example 13 In this embodiment, the high-density micron-line light source array structure with beam collimation is the same as that in Embodiment 1, except that the micro-light-emitting unit array uses 1024×2 independently controllable Micro-LED units, and the CMOS driving backplane contains 2048 independent driving units.

[0083] Example 14 like Figure 7 As shown, a galvanometer system including the high-density micron-level line light source array structure described above uses the line light source array structure described in Example 1 as the light source. It also includes a host computer, a central control unit, a high-density line light source module, a color combining system, a galvanometer body, a galvanometer drive controller, and a dedicated focusing field lens. The galvanometer body includes a reflecting mirror, a support bearing, a drive motor, and a high-precision position sensor. The galvanometer drive controller receives position commands, drives the motor, and reads feedback from the position sensor for closed-loop control. The galvanometer body is fixed to the system's optical platform by mechanical mounting components, and its reflecting mirror surface is located in the optical path of the emitted beam from the color combining system or the monochromatic line light source. The galvanometer drive controller receives Y-axis position and velocity commands sent from the output terminal B of the central control unit. The galvanometer drive controller feeds back the real-time high-precision Y-axis position signal read by the high-precision position sensor to the central control unit via analog output or digital interface as an input for optional compensation.

[0084] The galvanometer body is a high-dynamic-performance galvanometer-type galvanometer, the reflector is coated with a fused silica protective film, the drive motor is a moving coil or moving magnet type, and the high-precision position sensor is a photoelectric encoder or a capacitive displacement sensor.

[0085] The core working principle of the system lies in the central control unit's precise spatiotemporal synchronization of the illumination timing of the line light source micro-emitting units with the Y-axis position of the single-axis galvanometer, and the use of a dedicated field lens to ensure high-quality imaging. The operation procedure is as follows: Data reception and preprocessing: The host computer sends the two-dimensional image data to be exposed (organized by row / column) and scanning parameters (scanning speed V_scan, start position Y_start, end position Y_end, scanning direction, etc.) to the central control unit.

[0086] The central control unit parses the image data and converts it into a pixel grayscale / on / off data stream organized in columns (corresponding to the X-direction position). At the same time, it calculates the Y-axis target motion trajectory Y(t) of the galvanometer (a function of position, velocity, and acceleration as a function of time) based on the scanning parameters.

[0087] Synchronous timing computation (core): The central control unit calculates the lighting time of each column (or specific area) of micro-light-emitting units on the line light source in real time based on the following key factors: The trajectory of the preset target of the galvanometer.

[0088] The actual position feedback signal of the galvanometer (if closed-loop compensation is enabled).

[0089] Preset system delay parameters include: processing delay of control signals within the central control unit, delay of signal transmission to the line light source drive backplane, delay of the drive backplane responding to the lighting command, delay of signal transmission to the galvanometer driver, delay of the galvanometer driver responding and mechanical movement reaching the target position, and the time for the beam to travel in the optical path (usually very small and negligible).

[0090] Position mapping relationship: For a column on the line light source with a certain X-coordinate position, the corresponding target exposure position is the target Y-coordinate value on the workpiece. This target Y-value is directly related to the position and Y-value of the galvanometer at the moment of reflection (the field lens is responsible for linearly converting the angle change of the galvanometer into the Y displacement on the workpiece; usually, the target Y-value ≈ the galvanometer Y-value).

[0091] Example of calculating the lighting time: Core objective: When the actual position of the galvanometer reaches the target Y value (a certain X column), the beam emitted from that column should reach the corresponding position of the workpiece exactly.

[0092] Considering the main delays: Total galvanometer delay: The time required from the central control unit issuing the galvanometer movement command to the galvanometer actually moving to the target position (including signal processing, transmission, driver response, and mechanical movement time).

[0093] Light source illumination delay: The time required from the central control unit issuing a light-up command for a certain column to the actual emission of light from that column (including signal processing, transmission, drive backplane response, and light-emitting unit response time).

[0094] Ideal computational logic: The central control unit knows that the galvanometer needs to be moved to the target Y value (a certain X column) position.

[0095] Based on the preset motion trajectory of the galvanometer, the estimated time point when the galvanometer is expected to reach the target Y value (a certain X column) is calculated (referred to as the "galvanometer arrival time").

[0096] In order for the beam of this column to arrive at the workpiece exactly at the "expected time of galvanometer positioning", the beam must be emitted a long time in advance, such as the "light source lighting delay".

[0097] Therefore, the central control unit needs to send a command to the drive backplane to light up the column at the moment when the estimated time of the galvanometer's arrival is minus the light source illumination delay.

[0098] Advanced Functions (Closed-Loop Compensation): If the system enables real-time position feedback of the galvanometer, the central control unit can utilize this actual position information (not just the preset trajectory) and combine it with prediction algorithms (such as Kalman filtering) to more accurately estimate the actual time when the galvanometer reaches the target Y value (a certain X column). It can also dynamically adjust the timing of the illumination command for that column (advancing or delaying slightly) based on minute deviations between the actual and target positions, performing real-time compensation to further improve synchronization accuracy.

[0099] Linear light source emission: After receiving the control signal, the CMOS driver backplane drives the corresponding LED driver chip.

[0100] The LED driver chip drives the corresponding column of micro-light-emitting units to emit light at a specified grayscale at a precisely designated time by the central control unit.

[0101] The emitted light undergoes initial homogenization and collimation through the optical shaping layer inside the line light source.

[0102] The thermal management system dynamically adjusts the cooling power based on the instructions from the central control unit and the feedback from the temperature sensors to maintain a stable core temperature for the linear light source.

[0103] Beam color combining (color system): Light emitted from line sources of various wavelengths enters the color combining system.

[0104] The light beam first passes through a nanopillar array and other components for homogenization and diffusion (to improve uniformity).

[0105] Then, it is collimated or pre-focused by a high-NA cylindrical lens (to control the beam divergence angle).

[0106] Finally, at the color-combining prism, beams of different wavelengths at the same X position, illuminated strictly according to the synchronization command of the central control unit, are precisely combined and output as a linear beam with the desired color.

[0107] Galvanometer deflection: The galvanometer drive controller receives the Y-axis position command sent by the central control unit.

[0108] The drive controller drives the motor to move, causing the reflective lens to deflect precisely at the correct angle.

[0109] A high-precision position sensor monitors the deflection angle of the lens in real time (corresponding to the Y-direction position of the reflected beam).

[0110] The drive controller performs closed-loop control (such as PID control) and feeds back the real-time detected actual position signal of the galvanometer to the central control unit (for optional status monitoring and the aforementioned dynamic compensation calculation).

[0111] Key action: The galvanometer moves precisely to the target position required by the command at the "expected arrival time of the galvanometer" calculated by the central control unit (with an accuracy in microradians or micrometers).

[0112] Beam scanning and focusing imaging: A linear beam of light emitted from a color mixing system (or a monochromatic line light source) is incident on the reflecting surface of a galvanometer at a specific Y-axis deflection angle (position).

[0113] After the beam is reflected by the galvanometer, its propagation direction changes, and its deflection angle corresponds exactly to the Y position of the galvanometer.

[0114] The reflected beam enters a dedicated focusing field lens.

[0115] The field lens linearly converts the change in the incident angle into a Y-direction displacement on the workpiece plane.

[0116] at the same time: In the X direction (the length direction of the line light source), the field lens ensures that the light emitted by each micro-light-emitting unit (at different X positions) on the line light source is imaged onto the corresponding X coordinate of the workpiece plane with almost no distortion (minimal distortion) and high definition (high modulation transfer function value).

[0117] In the Y direction (scanning motion direction), the field lens ensures that the height (short side dimension) of the line beam remains constant throughout the entire scan path, the edges are very sharp (field curvature and astigmatism are minimal), and the light intensity distribution is very uniform.

[0118] Ultimately, at the current Y-coordinate position on the workpiece plane, a high-quality exposure line is formed that strictly corresponds to the X-direction of the line light source, has high-precision positioning, and high uniform light intensity.

[0119] Y-axis scan coverage: Under the command of the central control unit, the galvanometer continuously scans along the Y direction (from the starting position to the ending position) at a preset speed and trajectory.

[0120] The central control unit continuously and in real time calculates the line light source array (X position) that should be lit at this moment and its corresponding gray value based on the current motion state (position or predicted position) of the galvanometer, and sends the lighting command on time.

[0121] As the galvanometer moves continuously in the Y direction, the beams of light from different columns (different X positions) of the line light source, which are precisely illuminated, are continuously and accurately imaged onto different Y coordinate positions on the workpiece plane.

[0122] Final Result: Through continuous single-axis scanning in the Y direction by a galvanometer, combined with precise column-by-column illumination and rigorous timing control of a line light source in the X direction, the 2D image data provided by the host computer is completely "drawn" onto the workpiece surface with pixel-level precision, completing the exposure of the entire target area. For large workpieces, after each single Y scan, the workpiece platform can be controlled to move stepwise in the X direction for multiple scans and stitching.

Claims

1. A high-density micron-line light source array structure, characterized in that, Includes micro-light-emitting unit arrays and integrated driving systems; The micro-light-emitting unit array is a long strip array, using m×n independently controllable Micro-LED units. The center-to-center spacing of the units is 1μm, and the effective size of a single micro-light-emitting unit is submicron and <1μm. It supports R / G / B / UV multi-wavelength configuration and can customize wavelengths according to application requirements. The surface of the micro-light-emitting unit array is directly wafer-bonded to the optical metasurface layer; The integrated driving system includes a CMOS driving backplane, which is a silicon-based integrated circuit containing m×n independent driving units. Each independent driving unit corresponds one-to-one with a micro-light-emitting unit array light-emitting unit. The CMOS driving backplane is copper-copper hybrid bonded to the lower layer of the micro-light-emitting unit array. The CMOS driving backplane is connected to the FPGA main control module through an LVDS interface.

2. The high-density micron-line light source array structure according to claim 1, characterized in that, The values ​​are m≥200, n≥2, and m:n≥50.

3. The high-density micron-line light source array structure according to claim 1, characterized in that, The optical metasurface layer is a silicon dioxide film or silicon nitride film with a thickness of 0.55µm, an etched diameter of 100-300nm, a height of 200-800nm, and a spacing less than the emission wavelength.

4. The high-density micron-line light source array structure according to claim 1, characterized in that, The integrated heat dissipation substrate is a 2mm thick pure copper plate. The integrated heat dissipation substrate has an external heat dissipation device, which includes a water-cooled or high-speed centrifugal fan. The high-speed centrifugal fan has a wind speed >8m / s and a power <10W. A temperature sensor is embedded near the light-emitting unit array on the CMOS driving backplane. One temperature sensor is arranged for every 1024 units. The thermal conductivity of the thermally conductive silver paste on the CMOS driving backplane is ≥10W / m·K.

5. The high-density micron-line light source array structure according to claim 1, characterized in that, The FPGA main control module is connected to the galvanometer system via a DB9 interface; the CMOS driver backplane is bonded to the integrated heat dissipation substrate with thermally conductive silver paste; the FPGA main control module is a Xilinx Artix7 series, which includes a high-speed LVDS interface; the galvanometer system is a Y-axis scanning galvanometer with a scanning frequency ≥1kHz.

6. A method for controlling the high-density micron-line light source array structure according to any one of claims 1-5, characterized in that, Includes the following steps: Step 1: Data Input and Parsing The host computer sends image data streams to the FPGA main control module via the GigE gigabit network port; The FPGA main control module splits the image data into 65,536 independent pixel signals and transmits them to the CMOS driver backplane through the LVDS interface; Step 2, Pixel-level light control: After receiving the signal, the CMOS driver backplane latches the data into the SRAM cache for each driver unit. Based on preset PWM parameters, a customized current is output to the corresponding MicroLED within <100ns; 65,536 micro-luminescent units are illuminated point by point according to the image; Step 3, beam collimation: The outgoing light from the Lambert-distributed MicroLED enters the optical metasurface layer; the nanopillar array converts light with a divergence angle > 60° into a collimated beam through spatial phase modulation based on gradient refractive index design. Step 4, Dynamic Temperature Control: A temperature sensor monitors the chip temperature in real time; the temperature signal is transmitted to the FPGA main control module via the IC bus; the FPGA main control module executes the PID algorithm: if the temperature is >40℃, the fan PWM duty cycle is increased; if the temperature is >60℃, the MicroLED drive current is reduced. Step 5, Synchronous Scan: The FPGA main control module generates galvanometer control signals: it outputs sawtooth wave analog voltage to the galvanometer driver according to the image line frequency; when the galvanometer reaches the start position of each line, it sends a TTL synchronization pulse to trigger CMOS backplane exposure.

7. The method for controlling a high-density micron-line light source array structure according to claim 6, characterized in that, In step 2, the preset PWM parameter resolution is 8 bits, and the output current is 0.10mA within <100ns.

8. The method for controlling a high-density micron-line light source array structure according to claim 6, characterized in that, In step 3, the divergence angle of the collimated beam after conversion is <10°.

9. A method for controlling a high-density micron-line light source array structure according to claim 6, characterized in that, In step 4, the sampling rate of the temperature sensor when monitoring the chip temperature in real time is 1kHz; the adjustment range of the fan PWM duty cycle is 0~100%.

10. A method for controlling a high-density micron-line light source array structure according to claim 6, characterized in that, In step 5, the image line frequency is 10kHz.

11. A galvanometer system comprising the high-density micron-line light source array structure according to any one of claims 1-5, characterized in that, Using the line light source array structure described in any one of claims 1-5 as the light source, the system further includes a host computer, a central control unit, a high-density line light source module, a color combining system, a galvanometer body, a galvanometer drive controller, and a dedicated focusing field lens. The galvanometer body includes a reflecting mirror, a support bearing, a drive motor, and a high-precision position sensor. The galvanometer drive controller receives position commands, drives the motor to move, and reads feedback from the position sensor for closed-loop control. The galvanometer body is fixed on the system's optical platform, and its reflecting mirror is located in the optical path of the beam emitted by the color combining system or the monochromatic line light source. The galvanometer drive controller receives Y-axis position and velocity commands sent by the output terminal B of the central control unit. The galvanometer drive controller feeds back the real-time high-precision Y-axis position signal read by the high-precision position sensor to the central control unit through an analog output or a digital interface as an input for optional compensation.

12. A galvanometer system according to claim 11, characterized in that, The galvanometer body is a high-dynamic-performance galvanometer-type galvanometer, the reflecting mirror has a fused silica protective film, the drive motor is a moving coil or moving magnet type, and the high-precision position sensor is a photoelectric encoder or a capacitive displacement sensor.

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