Hyperparallel optical system and alignment method thereof

Abstract

The invention provides a hyper-parallel optical system and an alignment method thereof, the hyper-parallel optical system comprises at least two hyper-parallel optical modules, each hyper-parallel optical module comprises a packaging substrate, and an array device and a driving circuit integrated on the packaging substrate; the optical fiber array is connected between the two groups of super-parallel optical modules and is used for realizing optical signal transmission between the light source arrays and the detector arrays on the two groups of super-parallel optical modules; and the coupler is arranged between the end part of the optical fiber array and the array device, is used for realizing optical signal coupling between the optical fiber array and the array device, and comprises two coupling structures. A three-dimensional waveguide structure connected with the inlet end face and the outlet end face is arranged in the first coupling structure; the second coupling structure is a micro lens array directly formed on the end face of the optical fiber array. Through the innovative coupler design, the optical path is simplified, the coupling efficiency and the alignment precision are improved, the manufacturing cost is reduced, and the reliability and the expandability of the system are enhanced.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to a superparallel optical system and its alignment method. Background Technology

[0002] With the rapid development of data centers and artificial intelligence (AI) infrastructure, the demand for data transmission between chips and devices has surged, and traditional electrical interconnects are facing bottlenecks in terms of bandwidth, power consumption, and transmission distance. While technologies such as silicon photonics have partially alleviated these problems, their cost, reliability, and integration complexity remain challenges.

[0003] In the field of ultra-parallel optical communication, the "wide but slow" architecture employing Micro-LED or Micro-RC-LED transmitting arrays and Micro-PD receiving arrays has attracted considerable attention. However, the performance of such systems is highly dependent on beam coupling efficiency. Traditional coupling schemes generally employ a combination structure of "microlens array + mirror" to achieve optical path connection between the array devices and fiber arrays (such as multimode fiber arrays, imaging fiber arrays, or multi-core plastic fibers). This traditional approach has the following inherent drawbacks:

[0004] 1) High structural complexity and manufacturing difficulty: The traditional microlens + mirror combination involves multiple layers of optical elements, which increases the system size and manufacturing complexity, leading to increased costs and limiting large-scale production.

[0005] 2) Alignment accuracy issues and environmental sensitivity: Manual or semi-automatic alignment is easily affected by vibration and temperature, making it difficult to guarantee accuracy and resulting in low coupling efficiency. In dynamic environments or under high-temperature conditions, traditional solutions lack adaptive mechanisms and have insufficient vibration resistance.

[0006] 3) Efficiency and loss issues: The reflector introduces additional losses, and the spherical aberration of the microlens causes beam scattering, resulting in low overall coupling efficiency. The light source has low coupling efficiency and a short lifespan, failing to fully utilize the low-power advantages of optical connections.

[0007] 4) Compatibility and scalability limitations: It is difficult to adapt to various fiber arrays (such as multimode, imaging, or plastic fibers), has poor scalability, and is difficult to support ultra-high parallel channel requirements. Silicon photonics is sensitive to environmental conditions, and its interoperability is limited.

[0008] 5) Low assembly efficiency and insufficient reliability: The lack of an automatic feedback mechanism means assembly relies on manual labor, resulting in long production cycles and a high risk of errors. Traditional solutions have low reliability and a high failure rate, making it difficult to meet mass production requirements.

[0009] Therefore, there is an urgent need for a coupling and alignment solution that is simpler in structure, more accurate in alignment, more efficient, and easier to mass-produce. Summary of the Invention

[0010] Based on this, the present invention provides an ultra-parallel optical system and its alignment method. Through innovative coupler design and automatic alignment method, the optical path is simplified, coupling efficiency and alignment accuracy are improved, manufacturing costs are reduced, and the reliability and scalability of the system are enhanced.

[0011] In a first aspect, embodiments of this application provide an ultra-parallel optical system, comprising:

[0012] At least two ultra-parallel optical modules, each of which includes a packaging substrate and an array device and a driving circuit integrated on the packaging substrate; the array device includes a light source array and a detector array, and the driving circuit is electrically connected to the array device.

[0013] An optical fiber array is connected between two sets of the ultra-parallel optical modules to realize optical signal transmission between the light source array on one set of the ultra-parallel optical modules and the detector array on the other set of the ultra-parallel optical modules.

[0014] A coupler is disposed between the end of the fiber array and the array device to realize optical signal coupling between the fiber array and the array device;

[0015] The coupler includes:

[0016] The first type of coupling structure includes an inlet end face and an outlet end face, and its interior contains a three-dimensional waveguide structure connecting the inlet end face and the outlet end face; and / or;

[0017] The second type of coupling structure is a microlens array formed directly on the end face of the optical fiber array.

[0018] Optionally, when the coupler is the first type of coupling structure, the three-dimensional waveguide includes a helical segment, a straight segment, and a curved segment connected in sequence.

[0019] Optionally, the inlet end face and / or outlet end face of the first type of coupling structure are provided with a V-groove or a conical structure for assisting mechanical positioning.

[0020] Optionally, the waveguide core region of the three-dimensional waveguide structure has a gradually changing refractive index distribution along the waveguide propagation direction.

[0021] Optionally, the coupler may be made of silicon-based materials or polymer waveguides with a refractive index ranging from 1.45 to 1.55.

[0022] Optionally, the type of microlens in the second type of coupling structure includes at least one of spherical, conical, and wedge-shaped.

[0023] Optionally, when the microlens is a spherical lens, the end face of the spherical lens is coated with a reflective film.

[0024] Optionally, it also includes an actuator and a feedback control unit;

[0025] The actuator is connected to the coupler and is used to drive the coupler to perform micro-displacement;

[0026] The feedback control unit is integrated in the drive circuit and is electrically connected to the light source array, the detector array and the actuator respectively.

[0027] The driving circuit is used to control the actuator to adjust the position of the coupler according to the emission state of the light source array and the light signal received by the detector array through the feedback control unit, so as to realize automatic optical alignment between the fiber array and the ultra-parallel optical module.

[0028] Optionally, the light source array includes a miniature light-emitting diode array and / or a miniature resonant cavity light-emitting diode array; the detector array includes a silicon-based photodetector array;

[0029] The fiber array includes at least one of a multimode fiber array, an imaging fiber array, and a multi-core plastic fiber cable array.

[0030] Based on the same inventive concept, this application also provides an alignment method for an ultra-parallel optical system, used for aligning the ultra-parallel optical system provided in the first aspect, characterized in that the alignment method includes:

[0031] Step S1: Initial optical links are established by firstly optically coupling the light source array of the first ultra-parallel optical module to the first end of the fiber array and the detector array of the second ultra-parallel optical module to the second end of the fiber array through at least one first coupler and at least one second coupler, respectively.

[0032] Step S2: Detect the photoelectric signal generated after transmission through the initial optical link using the detector array of the second ultra-parallel optical module; generate a feedback control signal characterizing the current alignment deviation based on the preset mapping relationship between the photoelectric signal and the optical path alignment.

[0033] Step S3: According to the feedback control signal, the feedback control unit drives at least one actuator to adjust the spatial pose of the first coupler and / or the second coupler to optimize the optical coupling efficiency between the light source array and the fiber array, and between the detector array and the fiber array.

[0034] Step S4: Iterate through steps S2 to S3 until the photoelectric signal reaches or exceeds the preset target threshold, and determine that the alignment is complete; then, lock the state of the actuator so that the corresponding coupler remains in the final alignment position, and complete the optical path alignment of the ultra-parallel optical system.

[0035] This invention provides an ultra-parallel optical system comprising at least two ultra-parallel optical modules. Each ultra-parallel optical module includes a packaging substrate and an array device and a driving circuit integrated on the packaging substrate. The array device includes a light source array and a detector array, and the driving circuit is electrically connected to the array device. An optical fiber array is connected between the two sets of ultra-parallel optical modules to realize optical signal transmission between the light source array on one set of ultra-parallel optical modules and the detector array on the other set of ultra-parallel optical modules. A coupler is disposed between the end of the optical fiber array and the array device to realize optical signal coupling between the optical fiber array and the array device. The coupler innovatively proposed in this application includes a first type of coupling structure and / or a second type of coupling structure. The first type of coupling structure includes an inlet end face and an outlet end face, and its interior contains a three-dimensional waveguide structure connecting the inlet end face and the outlet end face. The second type of coupling structure is a microlens array formed directly on the end face of the optical fiber array. This application simplifies the optical path, improves coupling efficiency and alignment accuracy, reduces manufacturing costs, and enhances the reliability and scalability of the system through innovative coupler design.

[0036] Two novel coupling structures and an alignment method during testing and assembly are proposed for large-scale ultra-parallel communication applications using blue-green Micro-LEDs (micro-light-emitting diodes) or red Micro-RC-LEDs (micro-resonant cavity light-emitting diodes) in the form of Si-based Micro-PD (micro-photodetector) arrays, avoiding the limitations of traditional microlens + mirror combinations.

[0037] This system is designed for scenarios with large-scale transceiver arrays, such as inter-rack communication in data centers or between GPUs and HBMs in AI multi-chip modules, to achieve efficient alignment and coupling.

[0038] Through innovative design, the system significantly improves coupling efficiency (>90%), alignment accuracy (<0.5μm), and assembly efficiency (reducing manual labor time), while also lowering manufacturing costs and environmental sensitivity (vibration resistance). Attached Figure Description

[0039] Figure 1 This is a schematic diagram of a superparallel optical system using a first-type coupling structure provided in this application;

[0040] Figure 2 This is a schematic diagram of another type of coupling structure used in the superparallel optical system provided in this application;

[0041] Figure 3 yes Figure 1 A schematic cross-sectional view of a first-type coupling structure for an ultraparallel optical system is provided.

[0042] Figure 4 yes Figure 2 A cross-sectional schematic diagram of a second type of coupling structure for an ultraparallel optical system is provided.

[0043] Figure 5 yes Figure 2 A cross-sectional schematic diagram of a second type of coupling structure for an ultraparallel optical system is provided.

[0044] Figure 6 This is a schematic diagram of an alignment method for a superparallel optical system provided in this application;

[0045] Figure 7 This is a flowchart of an alignment method for a superparallel optical system using a first-type coupling structure, as provided in this application;

[0046] Figure 8 This is a flowchart of another alignment method for a superparallel optical system using a second-type coupling structure, as provided in this application.

[0047] Explanation of reference numerals in the attached figures:

[0048] 10. Ultra-parallel optical module; 20. Array device; 30. Coupler; 40. Fiber array;

[0049] 11. Packaging substrate; 12. Light source array; 13. Detector array; 14. Driving circuit; 15. Fiber optic cable fixing bracket;

[0050] 30a, First coupler; 30b, Second coupler;

[0051] 31. First type of coupling structure; 32. Second type of coupling structure;

[0052] 10a, First ultra-parallel optical module; 10b, Second ultra-parallel optical module. Detailed Implementation

[0053] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the present application and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present application are shown in the drawings, not the entire structure. Various modifications and variations can be made to the present application without departing from its spirit or scope, which will be apparent to those skilled in the art. Therefore, the present application is intended to cover modifications and variations of the present application that fall within the scope of the technical solutions claimed in the corresponding claims and their equivalents. It should be noted that the implementation methods provided in the embodiments of the present application can be combined with each other without contradiction.

[0054] Light-emitting diodes (LEDs) are a type of semiconductor diode that converts electrical energy into light energy. Like ordinary diodes, LEDs consist of a PN junction and exhibit unidirectional conductivity.

[0055] Pulse-width modulation (PWM) controls the on / off state of switching devices to produce a series of pulses of equal amplitude at the output, which are used to replace a sine wave or the desired waveform.

[0056] Micro-LED (Micro Light-Emitting Diode): An array of LEDs with dimensions in the micrometer range, used for high-density optical communication and displays.

[0057] Micro-Resonant Cavity Light-Emitting Diode (Micro-RC-LED) combines resonant cavity light-emitting diodes with AlAs lateral oxidation technology to improve external quantum efficiency, reduce operating current, and stabilize spectral wavelength.

[0058] Micro Photodetector (Micro-PD): A micrometer-scale photodetector array used to receive optical signals and convert them into electrical signals.

[0059] Silicon-based photodetector (Si-PD): An array-type photodetector based on silicon material, used to receive and convert optical signals into electrical signals.

[0060] CMOS integrated circuit (Complementary Metal-Oxide-Semiconductor Integrated Circuit, CMOS IC) is a low-power integrated circuit used to drive and control Micro-RC-LED arrays.

[0061] 3D Waveguide Coupler: A three-dimensional waveguide used for the alignment of array devices with fiber optic arrays and for coupling optical signals.

[0062] Fiber End-Face Lens Array: A lens array integrated on the end face of an optical fiber for direct coupling to an array device.

[0063] Multimode Fiber Array: A fiber optic array that supports multimode optical transmission and is used for short-distance, high-bandwidth communication.

[0064] Imaging Fiber Array: A fiber optic array used for image transmission, often used in parallel optical interconnects.

[0065] Multicore Plastic Optical Fiber Cable (Multicore POFCable) is a composite optical cable containing multiple plastic optical fiber cores. It uses polymethyl methacrylate (PMMA) core material and is covered with a fluoride cladding to support high-density optical signal transmission.

[0066] Photocurrent feedback: Closed-loop control that enables automatic alignment by monitoring the current of a photodetector.

[0067] Closed-Loop Automatic Control System: A feedback-based mechanical aid system used for precise alignment during assembly.

[0068] Figure 1 This is a schematic diagram of a superparallel optical system using a first-type coupling structure provided in this application. Figure 2 This is a schematic diagram of another type of coupling structure used in the superparallel optical system provided in this application. Figure 3 yes Figure 1 A cross-sectional schematic diagram of a first-type coupling structure for an ultra-parallel optical system is provided. Figure 4 yes Figure 2 A cross-sectional schematic diagram of a second type of coupling structure for an ultra-parallel optical system is provided, wherein, Figure 3 (1) is Figure 1 A cross-sectional view of the first type of coupling structure along the AA′ direction. Figure 3 (2) is Figure 3 (1) is a cross-sectional view along the BB′ direction; Figure 4 (1) is Figure 2 Schematic diagram of the second type of coupling structure in the middle. Figure 4 (2) is Figure 2 and Figure 4 The cross-sectional view along the CC′ direction in (1) of the diagram. Figure 4 (3) is Figure 2 and Figure 4 (1) End view along the DD′ direction in the middle.

[0069] refer to Figures 1-4 This application provides an ultra-parallel optical system 100, comprising two ultra-parallel optical modules 10, an optical fiber array 40 connecting the two sets of ultra-parallel optical modules 10, and a coupler 30 disposed at the end of the optical fiber array 40 and the ultra-parallel optical module 10. Each ultra-parallel optical module 10 includes a packaging substrate 11 and an array device 20 and a driving circuit 14 integrated on the packaging substrate 11; the array device 20 includes a light source array 12 and a detector array 13. The driving circuit 14 is electrically connected to the light source array 12 and the detector array 13. In this application embodiment, the ultra-parallel optical module 10 is integrated on a compact packaging substrate 11, the size of which is approximately 10mm × 10mm × 5mm, and the specific size can be reasonably adjusted according to actual needs.

[0070] An array of devices 20, such as a light source array 12 and a detector array 13, is integrated on the packaging substrate 11. The driving circuit 14 is a driving chip for the light source array 12 and the detector array 13, used to drive the light source array 12 to emit light and drive the detector array 13 to receive the optical signal transmitted through the fiber optic array 40. Among them, the light source array 12 serves as the light-emitting end and the detector array 13 serves as the light-receiving end.

[0071] The light source array 12 can also be called a light emitting array, and the detector array 13 can also be called a light receiving array. The light source array 12 can be a micro-light-emitting diode (Micro-LED) array and / or a micro-resonant cavity light-emitting diode (Micro-RC-LED) array, and the detector array 13 can be a silicon-based photodetector array.

[0072] The light source array 12 and the fiber optic array 40, as well as the detector array 13 and the fiber optic array 40, are directly coupled and connected via the fiber optic array 40. The fiber optic array 40 is used to realize optical signal transmission between the light source array 12 on one set of ultra-parallel optical modules 10 and the detector array 13 on another set of ultra-parallel optical modules 10. The fiber optic array 40 can be at least one of multiple multimode fiber arrays, imaging fiber arrays, or multi-core plastic fiber optic cable arrays. For example, the multimode fiber array 40 has a core diameter of 50 μm, enabling multimode transmission and helping to reduce dispersion. The imaging fiber array has a pixel resolution greater than 1000, used for high-resolution signal transmission. The multi-core plastic fiber optic cable array can use a polymethyl methacrylate (PMMA) core with a numerical aperture (NA) of 0.5, offering the advantage of low-cost, flexible transmission.

[0073] Coupler 30 is used to couple optical signals between fiber array 40 and ultra-parallel optical module 10. The material of coupler 30 includes, but is not limited to, silicon-based materials or polymer waveguides, with a refractive index ranging from 1.45 to 1.55. For example, the waveguide cross-sectional area ranges from 1 mm. 2 ~5mm 2 .

[0074] The coupler 30 includes a first type of coupling structure 31 and / or a second type of coupling structure 32. (See reference) Figure 1 and Figure 3 The first type of coupling structure 31 includes an inlet end face and an outlet end face, and internally contains a three-dimensional waveguide structure connecting the inlet end face and the outlet end face. This type of coupling structure can realize coupling from the light source to the optical fiber, and from the optical fiber to the detector. (Reference) Figure 2 and Figure 4 The second type of coupling structure 32 is a microlens array formed directly on the end face of the fiber array 40. This type of coupling structure can be directly processed on the end face of the optical fiber cable using a microlens array with end face focusing function to achieve direct coupling from the light source to the optical fiber.

[0075] Compared to traditional ultra-parallel optical systems, the two coupling structures provided in this application eliminate the need for traditional microlens and mirror combinations, reducing optical components, minimizing optical loss, and improving transmission efficiency. This system can improve computational efficiency and reliability, achieving efficient alignment and coupling, for communication scenarios with large-scale transceiver arrays, such as inter-rack communication in data centers or between Graphics Processing Units (GPUs) and High Bandwidth Memory (HBM) in AI multi-chip modules. For example, in data center networks, it can be used for ultra-parallel optical interconnects within or between server racks, providing high-density array communication and supporting cloud and AI workloads. In cloud computing environments, it enables protocol-independent network integration, supporting optical coupling of massively parallel channels. In industrial automation systems, it can be used for multi-point interconnection of PLCs, servo drives, and industrial robots, supporting array-style signal transmission. In fiber optic sensor networks, it can provide high-precision alignment coupling solutions for multi-point sensing systems such as temperature and pressure sensors.

[0076] This application significantly improves the coupling efficiency (>90%), alignment accuracy (<0.5μm), and assembly efficiency (reducing manual time) of ultra-parallel optical systems through innovative coupler design, while reducing manufacturing costs and environmental sensitivity (vibration resistance).

[0077] The specific structure of this invention is described in detail below, including product components, their positions, structures, and functional relationships, as well as the product's operation process (sequence and relationships of mechanical actions). The design principle is based on optical waveguide theory and automated control principles, aiming to simplify the optical path, reduce the number of components, and introduce closed-loop feedback during testing and assembly to achieve adaptive alignment.

[0078] refer to Figure 1 and Figure 3 The first type of coupling structure 31, also known as a 3D waveguide coupler, is a single device that can realize the alignment of devices in the form of light source array 12 (Micro-LED array or Micro-RC-LED array, transmitter) to fiber array 40, and from fiber array 40 to detector array 13 (Micro-PD array, receiver). It supports transmission of multimode fiber array, imaging fiber array, and multi-core plastic fiber cable array.

[0079] Specifically, when the coupler 30 is a first-type coupling structure 31, the three-dimensional waveguide path includes a helical segment, a straight segment, and a curved segment connected in sequence. In fabricating the parallel waveguide inside the first-type coupling structure 31, this application can use femtosecond laser direct writing technology to form a three-dimensional waveguide path within the glass substrate. Alternatively, a femtosecond laser (e.g., pulse width <100 fs, power 1mW~10mW) can be used to directly write the waveguide path, controlling the laser focus depth to form a three-dimensional route. For example, a helical segment or curved path can be formed by laser etching within the glass substrate, with a bending radius greater than 25 mm.

[0080] It should be noted that the core component of the first type of coupling structure 31 is a three-dimensional silicon-based, polymer waveguide, or other related material as the substrate, with waveguide design performed on the substrate using laser engraving or other techniques. The refractive index within the waveguide substrate can also be designed with a gradient, such as fabrication within a transparent substrate using femtosecond laser direct writing technology. The waveguide core region of the three-dimensional waveguide structure has a gradient refractive index distribution along the waveguide propagation direction. This design can match the array pixel size and improve optical coupling efficiency. The entrance end face of the first type of coupling structure 31 is adjacent to the array device 20 pixels, and the exit end face is connected to the fiber core of the fiber array 40, with a three-dimensional routing inside the waveguide connecting the two. (Continue to refer to...) Figure 1 When the first type of coupling structure 31 is working, the waveguide port captures the diverging beam emitted by the light source array 12 on the left first ultra-parallel optical module 10a. The light signal emitted by the light source array 12 is guided and focused by a gradient refractive index, and a parallel beam matching the fiber mode field is output at the exit end. Optionally, a V-groove or conical structure for auxiliary mechanical positioning can be provided on the inlet and / or outlet end faces of the first type of coupling structure 31 to provide mechanical positioning or other methods for fixing the position. At the optical signal output end, the optical signal enters the waveguide port from the light source array 12, is focused by the gradient structure and transmitted along a three-dimensional path, and is then emitted from the outlet end face and injected into the fiber core of the fiber array 40. At the optical signal receiving end, the optical signal enters the waveguide port end face of the right first type of coupling structure 31 from the fiber core of the fiber array 40, is focused by the gradient structure and transmitted along a three-dimensional path, and is then emitted from the outlet end face and transmitted to the detector array 13 on the right second ultra-parallel optical module 10b, thus realizing optical signal transmission. Compared to the traditional method, the first type of coupling structure 31 provided in this application simplifies the optical elements (i.e., there are no microlenses / mirrors). Tests have shown that the beam collimation is not offset at vibration frequencies >500Hz, thus indicating that the first type of coupling structure 31 provided in this application improves the vibration resistance performance.

[0081] As an example, the waveguide design of the first type of coupling structure 31 provided in this application uses femtosecond laser direct writing technology to form a three-dimensional optical waveguide circuit in a glass substrate, achieving high-precision alignment and optical signal transmission between the array device 20 and the fiber array 20. The design principle is based on the multiphoton absorption effect, increasing the refractive index of the substrate through local modification at the laser focal point to form the waveguide core region. A three-dimensional routing design (such as a spiral or curved path) is used inside the waveguide to minimize bending loss and match the array pixel size. The specific fabrication steps are as follows:

[0082] Step S11, Substrate preparation: Select borosilicate glass substrate. The reference parameters for the substrate are: refractive index of about 1.5, size ≤100×100 mm, and surface polishing to a roughness of <1nm to ensure no scattering during laser transmission.

[0083] Step S12, Laser Parameter Settings: A femtosecond laser is used, with the following laser energy parameters: pulse width < 100 fs, wavelength 1030 nm, repetition frequency 1 MHz, single pulse energy 100 nJ ~ 500 nJ, and scanning speed 10 mm / s ~ 100 mm / s. The energy density is controlled above the threshold, i.e., 10 W / cm² ~ 13 W / cm², to induce a local refractive index change Δn = +0.005 - 0.015. The range of laser parameters can be adjusted within an appropriate range depending on the actual situation. This embodiment is merely an example and is not intended to be limiting.

[0084] Step S13, 3D Route Planning: Use 3D design software to design the 3D route, placing the inlet end face close to the array device pixels (spacing <1μm) and the outlet end face aligned with the fiber core of the fiber array 20 (spacing <0.5μm). The internal route includes spiral segments (radius 50μm~200μm, used for fan-in compression of high-density pixels), straight segments (length 5mm~10mm, used for low-loss transmission), and curved segments (bending radius >25mm, achieving loss <0.01dB / 90°). Optionally, the curved path is optimized using Bezier curves to avoid mode leakage caused by sharp corners.

[0085] Step S14, End Face Treatment: Fabricate the edge coupling structure. One possible treatment method is to embed a V-groove (reference parameters: depth 2μm~5μm, angle 60°) into the inlet end face for mechanical positioning, and a conical structure can be used on the outlet end face to compensate for the difference in the mode field diameter. After laser writing, chemical polishing is performed to remove surface defects.

[0086] Step S15, Testing and Iteration: After writing the parameters, use an optical microscope to inspect the waveguide integrity of the first type of coupling structure, and adjust the laser energy parameters for iterative optimization. Determine the core spacing, bending radius, and spacing between Micro-LEDs, Micro-RC-LEDs, or Micro-PDs in the array device 20, with the operating wavelength being blue-green light.

[0087] The purpose of graded-index (GRIN) design is to gradually change the refractive index of the core region of the first-type coupling structure along the waveguide propagation direction (z-axis) to achieve mode field matching and low-loss transmission. The design principle is based on a parabolic distribution, aiming to reduce the mismatch between the diverging beam of the array device and the fiber mode field.

[0088] Figure 5 yes Figure 2 A cross-sectional schematic diagram of a second type of coupling structure for an ultra-parallel optical system is provided, wherein, Figure 5 (1) is Figure 2 and Figure 4 (1) End view of the second type of coupling structure along the DD′ direction. Figure 5 (2) is Figure 5 (1) is a schematic diagram of a single pixel using a spherical fiber optic lens. Figure 5 (3) is Figure 5 (1) A schematic diagram of a single pixel end using a tapered fiber optic lens.

[0089] Based on the above embodiments, continue to refer to Figure 2 , Figure 4 and Figure 5 The second type of coupling structure 32 is an optical fiber end-face lens array. By directly integrating the lens array on the optical fiber end face, direct coupling from the optical fiber array 40 to the array device 20 can be achieved, avoiding the need for additional optical components. Optionally, the microlenses 32a in the second type of coupling structure 32 include at least four types, such as spherical, spherical end-face coated with a reflective film, conical, and wedge-shaped lens arrays. The end-face shape of each microlens 32a can be rationally designed according to the application scenario.

[0090] It should be noted that the second type of coupling structure 32 is a lens array 32a directly fabricated on the end face of the arrayed optical fiber. The size of this lens array 32a matches the pixels of the device array 20. For example, the radius of curvature of the spherical lens ranges from 50μm to 1000μm, the distance H between the tip of the conical or wedge-shaped lens and the fiber core of the optical fiber array 40 ranges from 1μm to 100μm, and the cone angle is 30° to 130°. The distance H between the tip of the microlens 32a and the fiber core of the optical fiber array 40 can be reasonably designed, such as... Figure 5As shown in (2) in the figure. The deflection path angle of the wedge lens is 35°~130°. Optionally, the end face of the spherical lens, conical lens or wedge lens may be coated with an anti-reflective coating (reflectivity <1%) or a metallized (Al / Ag / Au, reflectivity >95%) reflective coating.

[0091] refer to Figure 2 When using an optical fiber end-face lens array for optical signal coupling, the positions of the components in the optical fiber end-face lens array are as follows: the end face of the lens array 32a is directly aligned with the pixel of the array device 20 (pixel spacing <1μm), the fiber core of the optical fiber array 40 is located at the rear end of the lens array 32a (spacing H value), and the entire array is embedded in the optical fiber cable fixing bracket 15 for fixing and maintaining collimation stability.

[0092] The fiber optic end-face lens array provided in this embodiment functions as follows: the fiber optic end-face lens array can focus and deflect the optical beam. Specifically, the spherical lens acts as a standard focusing lens (mode field matching >99%), the conical lens compresses the beam and reduces scattering, and the wedge-shaped lens, with a deflection path angle of 35°~130°, can deflect the optical path angle. The spherical lens, with the addition of a reflective coating, enhances the reflected light (metal layer reflection >95%).

[0093] The design principle of the fiber optic end-face lens array provided in this application embodiment is based on laser micromachining or mold forming. A lens array is directly formed by micromachining on the end face of the fiber optic array 40. This coupling structure can directly change the optical path, and testing shows a coupling efficiency ≥90%. It can support multimode fiber and also plastic fiber. As an example, the fabrication steps of the fiber optic end-face lens array are as follows:

[0094] Step S21: Select the fiber type of fiber array 40, such as using multimode fiber with a core diameter of 50μm.

[0095] Step S22: The end face shape of the multimode fiber is processed using a CO2 laser or mechanical grinding to form an fiber end face lens array. For example, a spherical lens is fabricated on the end face of the multimode fiber. The focal length of this spherical lens is 2mm~5mm. The surface of this spherical lens can also be an aspherical design, i.e., the curvature of the lens surface varies with the radius (asymmetric structure), usually defined by a polynomial equation. This application does not impose limitations on this. Aspherical surfaces can further optimize the light field distribution. Spherical aberration can measure the size of the focused spot; aspherical surfaces can focus the spot smaller, reducing spherical aberration.

[0096] Step S23: Deposit an antireflection coating on the surface of the fiber end-face lens array to complete the fabrication of the second type of coupling structure 32 on the end face of the fiber array 40. If vacuum evaporation is used, deposit an antireflection coating with a thickness of λ / 4 on the surface of the fiber end-face lens array, where λ is the laser wavelength.

[0097] Step S24: Optically couple the fabricated fiber array 40 to the array device 20. For example, it can be fixed using a fiber optic cable fixing bracket 15, such as FC / LC / SC / SMA, PC / APC, etc.

[0098] At the signal transmitting end, the optical signal diverges from the array device 20 into the lens end face of the fiber end face lens array, is focused / deflected and injected into the fiber core of the fiber array 40; at the signal receiving end, the optical fiber signal is directly transmitted to the detector array 13 through the lens of the fiber end face lens array.

[0099] The lens array provided in this application is directly integrated into the fiber end face, including various shapes, enabling direct coupling between the fiber and the array device. This application, through fiber end face processing technology, avoids additional optical components. This coupling structure eliminates the need for additional microlenses and / or mirror structures, reducing volume by at least 50% and cost by at least 30%. This enhances coupling efficiency and flexibility. Compared to traditional devices, eliminating the traditional combination of microlenses and mirrors simplifies optical path design, reduces manufacturing complexity, and improves system anti-interference capabilities, making it a highly efficient and economical hyperparallel communication solution.

[0100] Based on the above embodiments, the ultra-parallel optical system provided in this application further includes an actuator and a feedback control unit. The actuator is connected to the coupler 30 and is used to drive the coupler 30 to perform micro-displacement. The feedback control unit is integrated in the drive circuit 14, and its internal feedback circuit is electrically connected to the light source array 12, the detector array 13, and the actuator, respectively. For example, pulse width modulation (PWM) can be used to control the on / off state of the switching devices to realize the opening and closing of the light source array 12, the detector array 13, and the actuator. The drive circuit 14 is used to control the actuator to adjust the position of the coupler 30 through the feedback control unit according to the emission state of the light source array 12 and the optical signal received by the detector array 13, so as to realize automatic optical alignment between the fiber array 40 and the ultra-parallel optical module 10.

[0101] The feedback control unit provided in this application embodiment can optimize the alignment of the coupling structure with the array devices and fiber arrays, ensuring that the overall system achieves low coupling loss, longer transmission distance and higher received optical power in ultra-parallel communication.

[0102] Optionally, the feedback control unit uses a proportional-integral-derivative control algorithm to drive the actuator, which can be a microelectromechanical system (MEMS) actuator or a piezoelectric ceramic actuator. The actuator is a mechanical auxiliary system used to adjust the position of the coupler 30 to improve the coupling efficiency.

[0103] Based on the same inventive concept, this application also provides an alignment method for an ultra-parallel optical system, used to perform automatic alignment of the ultra-parallel optical system provided in the above embodiments. Figure 6 This is a schematic diagram of an alignment method for an ultra-parallel optical system provided in this application. Figure 7 This is a flowchart of an alignment method for a superparallel optical system using a first-type coupling structure, as provided in this application. Figure 8 This is a flowchart of another alignment method for a superparallel optical system using a second-type coupling structure, as provided in this application. (Refer to...) Figures 1-8 The alignment method for a superparallel optical system provided in this application includes:

[0104] Step S1: Initial optical coupling is performed between the light source array of the first ultra-parallel optical module and the first end of the fiber array, and between the detector array of the second ultra-parallel optical module and the second end of the fiber array, respectively, through at least one first coupler and at least one second coupler, to establish an initial optical link.

[0105] Step S2: Detect the photoelectric signal generated after transmission through the initial optical link using the detector array of the second ultra-parallel optical module; generate a feedback control signal characterizing the current alignment deviation based on the preset mapping relationship between the photoelectric signal and the optical path alignment.

[0106] The photoelectric signal includes at least photocurrent, voltage, or digital quantity converted from analog to digital, and the preset mapping relationship is obtained through pre-calibration or real-time calculation.

[0107] Step S3: According to the feedback control signal, the feedback control unit drives at least one actuator to adjust the spatial pose of the first coupler and / or the second coupler to optimize the optical coupling efficiency between the light source array and the fiber array, and between the detector array and the fiber array.

[0108] Step S4: Iterate through steps S2 to S3 until the photoelectric signal reaches or exceeds the preset target threshold, and the alignment is determined to be complete. Then, lock the state of the actuator so that the corresponding coupling structure remains in the final alignment position, and complete the optical path alignment of the ultra-parallel optical system.

[0109] Specifically, the alignment method for the ultra-parallel optical system provided in this application embodiment achieves precise alignment during the assembly process through loop automatic control of the photocurrent feedback of the detector array 13, forming a closed-loop automation in alignment. This alignment method is suitable for signal transmission and reception between ultra-parallel optical modules with relatively large array sizes, and is applicable to scenarios such as interconnection between data center chips. It supports multi-channel high-bandwidth transmission and has environmental adaptability and scalability.

[0110] As an example, continue to refer to Figure 1 and Figure 2 The light source array 12 uses a Micro-LED or Micro-RC-LED array, the detector array 13 uses a Micro-PD array, and the feedback circuit of the feedback control unit is located in the module circuit board of the drive circuit. The actuator is a MEMS actuator, fixed at the coupling interface. The Micro-PD array is used to monitor the coupled photocurrent signal (10μA~1 mA), and the feedback control signal is used to drive the actuator to adjust the position of the coupler 30. Based on the linear relationship between photocurrent and alignment, this application uses a proportional-integral-derivative (PID) control algorithm in the feedback control unit to ensure a stable control loop. The peak current corresponds to the optimal alignment position. The actuator's response time is <1ms, and its accuracy is <0.5μm.

[0111] refer to Figure 7 The specific implementation steps are as follows:

[0112] Step S31: First, perform initial assembly by coarsely aligning the light source array and detector array with the optical fiber.

[0113] Specifically, please refer to Figure 1 and Figure 2 The first coupler 30a is coarsely aligned with the pixels of the light source array 12 and the first end of the fiber array 40 on the first super-parallel optical module 10a, respectively. The second coupler 30b is coarsely aligned with the pixels of the detector array 13 and the second end of the fiber array 40 on the second super-parallel optical module 10b, respectively, forming an initial optical link. The first coupler 30a and the second coupler 30b can employ either a first-type coupling structure 31 or a second-type coupling structure 32. The first-type coupling structure 31 is a 3D waveguide coupler, and the second-type coupling structure 32 is a fiber end-face lens array.

[0114] Step S32: Transmit / receive optical signals. The Micro-LED array emits blue-green light signals or the Micro-RC-LED array emits red light signals. The Micro-PD array receives the optical signals and converts them into photocurrent signals.

[0115] Step S33: Couple the beam to the fiber array 20. The transmitted signal is coarsely aligned into the coupler 30 (3D waveguide coupler / fiber end-face lens array), focused and injected into the multi-core fiber optic cable, and received by the coarse alignment. The Micro-PD array receives the signal and prepares for reverse transmission. The fiber array 20 includes an optical cable containing multiple multimode fibers, imaging fibers, and plastic fibers.

[0116] Step S33: The Micro-PD array feeds back the photocurrent signal to control mechanical alignment. During assembly, the Micro-PD array monitors the current, the feedback circuit processes the photocurrent signal, and based on the linear relationship between photocurrent and alignment, the feedback control unit uses a proportional-integral-derivative (PID) control algorithm (PID algorithm proportional P=0.5, integral I=0.1, derivative D=0.05) to drive the actuator (step 0.1μm) to adjust the position of coupler 30 for mechanical alignment. This process is iterated until the photocurrent signal reaches its maximum (threshold > 90% peak value). The position of coupler 30 corresponding to the maximum photocurrent signal is the optimal alignment position.

[0117] Step S34: After reaching the optimal alignment position, lock the position of coupler 30 using mechanical clamps or adhesive. Optimize and lock the position to ensure stable transmission by coupler 30. Specifically, after multiple iterations, find the optimal position of coupler 30 and lock it in place. The ultra-parallel optical system provided in this application supports transmission distances from 1m to 50m, speeds from 100Gbps to 1Tbps, and a bit error rate (BER) < 10. -6 Bit Error Rate (BER) refers to the proportion of erroneous bits to the total number of transmitted bits.

[0118] In summary, the ultra-parallel optical system provided in this application, through two novel coupling structures (3D waveguide coupler and fiber end-face lens array) and a closed-loop automated alignment method utilizing photodetector feedback, forms a loop automatic control system by monitoring photocurrent and combining it with mechanical adjustments. This system optimizes the alignment accuracy of the optical link in real time during assembly, and further achieves dynamic adaptation through a PID control algorithm using a feedback control unit. This overcomes the limitations of manual alignment during assembly and testing, achieving significant technical effects.

[0119] Specifically, the advantages of the alignment method for a superparallel optical system provided in this application embodiment are as follows:

[0120] 1) Improved coupling efficiency: This application improves coupling efficiency to >90% through the design of the 3D waveguide coupler with graded refractive index and optimization of the fiber end-face lens array, which is about 20% higher than the traditional combination of microlenses and mirrors. Experimental data show that the optical transmission loss of the ultra-parallel optical system provided by the embodiments of this application is reduced to <10% (the optical transmission loss of the traditional combination of microlenses and mirrors is >20%), thereby significantly improving signal transmission quality.

[0121] 2) Improved alignment accuracy and automation: The alignment method for the ultra-parallel optical system provided in this application reduces manual intervention, shortens assembly time by about 50%, and achieves alignment accuracy of <0.5μm, overcoming the shortcomings of traditional manual alignment which is susceptible to vibration and temperature.

[0122] 3) Reduced manufacturing costs: The super-parallel optical system provided in this application eliminates redundant optical components (such as microlenses and mirrors), reducing manufacturing costs by approximately 30%, simplifying the production process, and improving economic efficiency.

[0123] 4) Enhanced compatibility and scalability: The ultra-parallel optical system provided in this application supports multimode fiber, imaging fiber and plastic fiber arrays, and expands the number of channels to hundreds or even thousands, overcoming the limitations of traditional solutions in terms of insufficient fiber type adaptability.

[0124] 5) Improved reliability and stability: The feedback mechanism of the ultra-parallel optical system provided in this application can ensure long-term alignment stability, with a mean time between failures (MTBF) of over 100,000 hours, which is significantly improved compared to traditional solutions and adapts to the needs of high dynamic environments.

[0125] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Features of various embodiments of the present invention can be partially or wholly coupled or combined with each other, and can cooperate and be technically driven in various ways. Various obvious changes, readjustments, combinations, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Many other equivalent embodiments may be included without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A superparallel optical system, characterized in that, include: At least two ultra-parallel optical modules, each of which includes a packaging substrate and an array of devices and a driving circuit integrated on the packaging substrate; The array device includes a light source array and a detector array, and the driving circuit is electrically connected to the array device; An optical fiber array is connected between two sets of the ultra-parallel optical modules to realize optical signal transmission between the light source array on one set of the ultra-parallel optical modules and the detector array on the other set of the ultra-parallel optical modules. A coupler is disposed between the end of the fiber array and the array device to realize optical signal coupling between the fiber array and the array device; The coupler includes: The first type of coupling structure includes an inlet end face and an outlet end face, and its interior contains a three-dimensional waveguide structure connecting the inlet end face and the outlet end face; and / or; The second type of coupling structure is a microlens array formed directly on the end face of the optical fiber array.

2. The ultra-parallel optical system according to claim 1, characterized in that, When the coupler is the first type of coupling structure, the three-dimensional waveguide includes a helical segment, a straight segment, and a curved segment connected in sequence.

3. The ultra-parallel optical system according to claim 2, characterized in that, The inlet and / or outlet end faces of the first type of coupling structure are provided with V-grooves or conical structures for auxiliary mechanical positioning.

4. The ultra-parallel optical system according to claim 2, characterized in that, The three-dimensional waveguide structure has a gradually changing refractive index distribution in the waveguide core region along the waveguide propagation direction.

5. The ultra-parallel optical system according to claim 2, characterized in that, The coupler can be made of silicon-based materials or polymer waveguides with a refractive index ranging from 1.45 to 1.

55.

6. The ultra-parallel optical system according to claim 1, characterized in that, The type of microlens in the second type of coupling structure includes at least one of spherical, conical, and wedge-shaped.

7. The ultra-parallel optical system according to claim 6, characterized in that, When the microlens is a spherical lens, the end face of the spherical lens is coated with a reflective film.

8. The superparallel optical system according to claim 1, characterized in that, It also includes actuators and feedback control units; The actuator is connected to the coupler and is used to drive the coupler to perform micro-displacement; The feedback control unit is integrated in the drive circuit and is electrically connected to the light source array, the detector array and the actuator respectively. The driving circuit is used to control the actuator to adjust the position of the coupler according to the emission state of the light source array and the light signal received by the detector array through the feedback control unit, so as to realize automatic optical alignment between the fiber array and the ultra-parallel optical module.

9. The ultra-parallel optical system according to claim 1, characterized in that, The light source array includes a miniature light-emitting diode array and / or a miniature resonant cavity light-emitting diode array; the detector array includes a silicon-based photodetector array. The fiber array includes at least one of a multimode fiber array, an imaging fiber array, and a multi-core plastic fiber cable array.

10. An alignment method for an ultra-parallel optical system, used for aligning the ultra-parallel optical system according to any one of claims 1-9, characterized in that, The alignment method includes: Step S1: Initial optical links are established by firstly optically coupling the light source array of the first ultra-parallel optical module to the first end of the fiber array and the detector array of the second ultra-parallel optical module to the second end of the fiber array through at least one first coupler and at least one second coupler, respectively. Step S2: Detect the photoelectric signal generated after transmission through the initial optical link using the detector array of the second ultra-parallel optical module; generate a feedback control signal characterizing the current alignment deviation based on the preset mapping relationship between the photoelectric signal and the optical path alignment. Step S3: According to the feedback control signal, the feedback control unit drives at least one actuator to adjust the spatial pose of the first coupler and / or the second coupler to optimize the optical coupling efficiency between the light source array and the fiber array, and between the detector array and the fiber array. Step S4: Iterate through steps S2 to S3 until the photoelectric signal reaches or exceeds the preset target threshold, and determine that the alignment is complete; then, lock the state of the actuator so that the corresponding coupler remains in the final alignment position, and complete the optical path alignment of the ultra-parallel optical system.

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