An ultra-miniature modular silicon photonic gyroscope and its automated and efficient assembly method

Abstract

This invention provides an ultra-miniature modular silicon photonic gyroscope and an automated, efficient assembly method. The gyroscope includes a housing and, within the housing, a sensor module, an integrated optical path module, and an integrated circuit module arranged sequentially from bottom to top. The housing comprises a lower housing, a middle housing, an upper housing, and a cover plate connected sequentially from bottom to top. A first connecting plate and a second connecting plate are respectively disposed inside the middle and upper housings. The sensor module includes a Y-waveguide phase modulator and an optical fiber loop, mounted on the upper and lower surfaces of the first connecting plate. The integrated optical path module and the integrated circuit module are respectively mounted on the lower and upper surfaces of the second connecting plate of the upper housing. The cover plate includes an insulator connector and a debugging interface. This invention, through integrated modular design, significantly reduces the overall size of the silicon photonic gyroscope and simplifies the subsequent assembly method.

Description

Technical Field

[0001] This invention belongs to the field of optical sensing technology, specifically relating to an ultra-miniature modular silicon photonic gyroscope and an automated and efficient assembly method. Background Technology

[0002] The essence of integrated fiber optic gyroscopes is to use advanced integrated optoelectronic technology and processes to integrate the light source, detector, coupler, phase modulator and sensitive ring onto a single optical chip, thereby enabling mass production of fiber optic gyroscopes and reducing gyroscope size and production costs.

[0003] Silicon photonic gyroscopes are a prominent example of integrated fiber optic gyroscopes. They use silicon as a medium and achieve partial or complete on-chip integration of optical devices through silicon-based multi-material integration. Due to the versatility of silicon, silicon photonic gyroscopes possess the characteristics of traditional optical gyroscopes, such as all-solid-state operation, fast startup, and high dynamic range. This significantly reduces the size, weight, power consumption, and cost of the gyroscope (SWaP-C). Moreover, since silicon material processing is similar to CMOS processes, silicon-based integration technology holds promise for achieving the fusion of the gyroscope's optical and electrical paths, making it an important future development direction.

[0004] Silicon photonic gyroscopes have a simpler optical path. The optical path splicing, fiber coiling, and pigtail curing processes in traditional fiber optic gyroscope manufacturing are largely replaced by the design and fabrication of silicon photonic chips. This simplified optical path structure greatly simplifies the assembly process compared to traditional fiber optic gyroscopes. Therefore, convenient and automated assembly procedures and processes can be adopted in the overall gyroscope design, significantly reducing material and manufacturing costs. This meets the urgent need for low-cost fiber optic gyroscopes in rapidly developing fields such as autonomous driving, drones, and industrial robots. Furthermore, besides cost considerations, expanding application areas also require fiber optic gyroscopes to have a small size while maintaining a certain level of accuracy. However, size reduction brings three prominent problems: large temperature rise, full-temperature drift, and enhanced electromagnetic radiation, which severely restrict the application of silicon photonic gyroscopes in these fields. In summary, there is an urgent need for a modular silicon photonic gyroscope structure based on silicon photonic chips and its assembly process to reduce the gyroscope size to about 30mm, while ensuring assembly efficiency and first-pass yield at such a small size. In terms of performance design, it is necessary to reduce the power consumption and temperature rise of the gyroscope, suppress electromagnetic radiation noise through good structural design, improve the accuracy of silicon photonic gyroscope to within 0.1° / h, and improve the environmental adaptability in engineering applications. Summary of the Invention

[0005] The present invention aims to solve one of the above-mentioned technical problems by providing an ultra-small modular silicon photonic gyroscope and an automatic and efficient assembly method. Through integrated modular design, the overall size of the silicon photonic gyroscope is greatly reduced and the subsequent assembly method is simplified.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0007] This invention provides an ultra-miniature modular silicon photonic gyroscope, comprising a housing and a sensing meter module, an integrated optical path module, and an integrated circuit module arranged sequentially from bottom to top within the housing;

[0008] The housing includes a lower housing, a middle housing, an upper housing, and a cover plate connected sequentially from bottom to top. The middle housing and the upper housing are respectively provided with a first connecting plate and a second connecting plate inside.

[0009] The sensitive meter module includes a Y-waveguide phase modulator and an optical fiber loop. The optical fiber loop is installed on the lower surface of the first connecting plate of the middle housing, and the Y-waveguide phase modulator is installed on the upper surface of the first connecting plate of the middle housing.

[0010] The integrated optical path module is installed on the lower surface of the second connecting plate of the upper housing and includes a silicon photonic integrated device and a drive control circuit. The silicon photonic integrated device integrates a light source, a detector, and a coupler for gyroscope emission, beam splitting, beam combining, and signal detection. The drive control circuit is used to perform constant temperature and current control on the silicon photonic integrated device. The silicon photonic integrated device and the Y-waveguide phase modulator are connected by a single fiber fusion point.

[0011] The integrated circuit module is mounted on the upper surface of the second connecting plate of the upper housing and is used for data modulation and demodulation and gyroscope communication; the integrated optical path module is connected to the integrated circuit module through a pair of plugs.

[0012] The cover plate includes an insulator connector and a debugging interface. The sealed insulator connector is used for external power supply and data communication, and the debugging interface is used for FPGA program debugging of the silicon photonic gyroscope.

[0013] Furthermore, the two output ports of the Y-waveguide phase modulator are directly coupled to the two pigtails of the fiber loop.

[0014] Furthermore, the optical fiber between the silicon photonic integrated device and the Y-waveguide phase modulator comprises two segments: the output segment L1 of the silicon photonic integrated device and the input segment L2 of the Y-waveguide phase modulator. The length of L2 is 2L1, and the length of L1 is between 0.8 and 1.2 m. L1 and L2 are fused together at 45° on-axis.

[0015] Furthermore, the silicon photonic integrated device is soldered to the drive control circuit via a 14-pin butterfly package.

[0016] Furthermore, the integrated circuit module includes two male connectors, the drive control circuit includes two female connectors that match the size of the male connectors, and the second connecting plate of the upper housing includes two arc-shaped grooves for the connectors to pass through.

[0017] Furthermore, the lower and upper surfaces of the first connecting plate of the middle housing are respectively provided with concave grooves for assembling the optical fiber loop and the Y waveguide phase modulator, and the first connecting plate of the middle housing includes side holes through which the pigtail of the optical fiber loop passes.

[0018] Furthermore, the insulator connector uses glass insulator pins, and the pins are made of iron-nickel-cobalt glass-sealed alloy. The glass insulator has 7 pins, of which pins 1 to 3 are power supply and ground pins, respectively, and pins 4 to 7 are data differential output pins DO+ and DO-, and expandable command transmission pins DI+ and DI-, respectively. The spacing between pins 1 to 3 is different from the spacing between pins 1 to 4, which is used for anti-reverse insertion function.

[0019] This invention also provides an automated and efficient assembly method for an ultra-miniature modular silicon photonic gyroscope, comprising the following steps:

[0020] Control the robotic arm to grasp the optical fiber ring, apply adhesive to the optical fiber ring, and attach it to the lower surface of the first connecting plate of the middle shell;

[0021] The two pigtails of the optical fiber loop are passed through the first connecting plate, and the robotic arm is controlled to grasp the middle shell and the lower shell for alignment and welding.

[0022] Control the robotic arm to grasp the Y-waveguide phase modulator, apply adhesive to the Y-waveguide phase modulator, and adhere it to the upper surface of the first connecting plate of the middle shell;

[0023] Axial alignment of fiber optic loop pigtails;

[0024] Grind the end face of the fiber optic loop pigtail;

[0025] The two output ends of the Y-waveguide phase modulator are directly coupled to the fiber loop pigtail.

[0026] The robotic arm is controlled to grasp the silicon photonic integrated device, which is then soldered to the drive control circuit and installed on the lower surface of the second connecting plate of the upper housing.

[0027] The robotic arm is controlled to grasp the upper housing and approach the sensitive meter module, and to fuse the output pigtail of the silicon photonic integrated device with the input single fiber of the Y waveguide phase modulator.

[0028] Fiber optic winding and dispensing;

[0029] The robotic arm is controlled to grasp and align the upper and middle shells. After connecting the modulation line, the upper and middle shells are welded together.

[0030] The control robot grips the integrated circuit module, which is mounted on the upper surface of the second connecting plate of the upper housing, and the cover plate is welded to the upper housing.

[0031] Debugging the integrated circuit module program functions;

[0032] A circular encapsulation plate is placed at the debugging interface and then welded and sealed.

[0033] Furthermore, in the polishing process of the optical fiber ring, the polishing disc follows an 8-shaped path.

[0034] The beneficial effects of this invention compared to the prior art are as follows:

[0035] This invention proposes an ultra-miniature modular silicon photonic gyroscope and an automated and efficient assembly method. The gyroscope consists of only three parts: a silicon photonic integrated module, a signal detection module, and a sensitive meter module. The maximum external size of each module does not exceed 30mm, reducing the overall size of the gyroscope to less than 50% of that of traditional fiber optic gyroscopes, and has the characteristics of an ultra-miniature structure.

[0036] This invention proposes an ultra-miniature modular silicon photonic gyroscope. Regarding gyroscope performance: a polarization noise suppression optical path structure is designed, and the direct coupling process with a band ring effectively suppresses polarization coupling noise under small bending radii. In terms of structural design, a gyroscope structure with separate optoelectronic modules is designed. The optoelectronic modules are assembled and manufactured in parallel, ultimately connected via flexible circuit traces or a single optical fiber. This saves at least half the assembly time compared to traditional fiber optic gyroscopes. Furthermore, metal laser welding is used to achieve complete sealing of the gyroscope, ensuring its airtightness and thus improving its environmental adaptability.

[0037] The ultra-miniature silicon photonic gyroscope proposed in this invention has the technical advantages of high precision, ultra-miniature size, and modular assembly. Attached Figure Description

[0038] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0039] Figure 1 A cross-sectional view of an ultra-miniature modular silicon photonic gyroscope provided for a specific embodiment of the present invention;

[0040] Figure 2 Exploded view of an ultra-miniature modular silicon photonic gyroscope provided for a specific embodiment of the present invention;

[0041] Figure 3 A schematic diagram of the connection relationship of the ultra-small modular silicon photonic gyroscope provided for a specific embodiment of the present invention;

[0042] Figure 4 A schematic diagram of the fiber optic melting point of the integrated optical path module and the sensitive meter module provided for a specific embodiment of the present invention;

[0043] Figure 5 A schematic diagram of the grinding and polishing process of the end face of the direct coupling point of the optical fiber loop pigtail provided in a specific embodiment of the present invention;

[0044] Figure 6 A schematic diagram of the connection of an ultra-small modular silicon photonic gyroscope structure provided in a specific embodiment of the present invention;

[0045] Figure 7 This is a schematic diagram of the structure of an ultra-miniature sealed insulator connector provided for a specific embodiment of the present invention.

[0046] The above figures include the following reference numerals:

[0047] 1. Sensitive meter module; 11. Y-waveguide phase modulator; 12. Fiber optic loop; 2. Integrated optical path module; 21. Drive control circuit; 22. Silicon photonic integrated device; 3. Integrated circuit module; 4. Housing; 41. Insulator connector; 42. Debugging interface; 43. Cover plate; 44. Upper housing; 45. Middle housing; 46. Lower housing; 47. Connecting part. Detailed Implementation

[0048] Specific embodiments of the present invention will now be described in detail. In the following description, specific details are set forth for purposes of explanation and not limitation, in order to aid in a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced in other embodiments departing from these specific details.

[0049] It should be noted that, in order to avoid obscuring the invention with unnecessary details, only the device structure and / or processing steps closely related to the solution of the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0050] As one aspect of the present invention, an ultra-miniature modular silicon photonic gyroscope is provided, such as Figures 1-7 As shown, it comprises three parts: an integrated optical path module 2, an integrated circuit module 3, a sensitive meter module 1, and a housing 4, wherein:

[0051] The housing 4 includes a lower housing 46, a middle housing 45, an upper housing 44, and a cover plate 43 connected sequentially from bottom to top. The middle housing 45 and the upper housing 44 are respectively provided with a first connecting plate and a second connecting plate.

[0052] The integrated optical path module 2 consists of a silicon photonic integrated device 22 (a packaged silicon photonic chip that integrates a light source, detector, and coupler for gyroscope emission, beam splitting, beam combining, and signal detection) and a drive control circuit 21. The silicon photonic integrated device is soldered onto the drive control circuit, which enables constant temperature and current control of the silicon photonic integrated device. The integrated optical path module 2 is installed on the lower surface of the second connecting plate of the upper housing 44.

[0053] The sensitive meter module 1 consists of a Y-waveguide phase modulator 11 and an optical fiber loop 12. The optical fiber loop 12 is installed on the lower surface of the first connecting plate of the middle housing 45, and the Y-waveguide phase modulator 11 is installed on the upper surface of the first connecting plate of the middle housing 45.

[0054] Integrated circuit module 3 uses application-specific integrated circuits (ASICs) as its core to build signal processing circuits, which are installed on the upper surface of the second connecting board of the upper housing to realize silicon photonic gyroscope data modulation and demodulation and gyroscope communication output.

[0055] The integrated optical path module 2 and the sensitive meter module 1 are connected by a single optical fiber fusion point, and the integrated optical path module 2 and the integrated circuit module 3 are connected by a pair of plugs. The assembly of the entire optical path and circuit is extremely simple.

[0056] The integrated optical path module 2 has only circuit soldering points for silicon photonic integrated devices and drive control circuits, with a total of 14 silicon photonic integrated device pins connected to circuit pads.

[0057] The sensitive meter module has only two fiber direct coupling points, which connect the two fibers of the fiber loop to the two output ports of the Y-waveguide phase modulator.

[0058] Furthermore, the upper and lower surfaces of the first connecting plate of the middle housing 45 are respectively provided with concave grooves for assembling the fiber optic loop and the Y-waveguide phase modulator, and the first connecting plate of the middle housing includes a side hole through which the fiber optic loop pigtail passes. The second connecting plate of the upper housing 44 includes an arc-shaped hole through which the connector passes.

[0059] Furthermore, the fiber optic melting point of the integrated optical path module and the sensitive meter module is as follows: Figure 4As shown, the connecting fiber between the two consists of two segments with a fiber fusion point in the middle. One segment is the output segment of the silicon photonic integrated device, with a pigtail length designed as L1, and L1 is set between 0.8-1.2m. The other segment is the input segment of the Y-waveguide phase modulator, with a single fiber length designed as L2, and L2 is 2L1. For fiber fusion splicing, the two fiber segments are fused at a 45° angle with an axial splice error of ±0.2°. The main advantages of this optical path fusion splicing scheme are twofold: first, by constructing a fiber depolarizer structure through a 1:2 length and 45° axial splicing method, the polarization noise problem caused by excessive pigtail stress under small bending radii is effectively suppressed; second, the effective control of the pigtail length avoids the pigtail accumulation problem caused by excessive length, which makes gyroscope assembly difficult.

[0060] Furthermore, the end face polishing process of the two direct coupling points of the sensitive meter module (i.e., pigtail 1 and pigtail 2 of the fiber optic loop) is as follows: Figure 5 As shown, in traditional manufacturing processes, because there are no loops at the rear of the pigtail, the pigtail is rotated together with the polishing fixture. However, with the addition of loops, especially as the number of loops increases, the polishing fixture itself does not have enough space to support the storage of the loops, so the polishing process needs to be improved.

[0061] To improve the efficiency of mass production, this invention proposes an end-face polishing process based on figure-eight grinding control. One of the pigtails output from the fiber loop is clamped by a fiber clamp, and then the grinding disk is controlled to move along a figure-eight path to complete the end-face grinding and polishing. By adopting this grinding and polishing process, the fiber clamp, which originally needs to rotate, does not rotate, thus ensuring that the pigtail of the fiber loop does not suffer from excessive torque due to rotation, or even breakage. Moreover, fiber loops can be stacked around the polishing equipment according to actual needs, which greatly improves the grinding and polishing efficiency.

[0062] Furthermore, the overall structure of the ultra-miniature silicon photonic gyroscope includes one specially designed ultra-miniature sealed insulator connector for external power supply and data communication, two debugging interfaces for FPGA program debugging before overall sealing, and four mounting holes for a stable connection and heat dissipation with the external structural platform. The gyroscope's internal structure is compact, consisting of three parts from bottom to top: a sensor module (including an optical fiber loop and a Y-waveguide phase modulator), an integrated optical path module (including silicon photonic integrated devices and drive control circuitry), and an integrated circuit module.

[0063] Furthermore, the internal interconnections of the ultra-miniature modular silicon photonic gyroscope are as follows: Figure 6 As shown, the three modules are connected together. The silicon photonic integrated devices on the integrated optical path module are soldered to the drive control circuit through 14-pin butterfly packages. The integrated optical path module and the integrated circuit module are connected through plug-in connectors, which has the advantages of reliability and convenience.

[0064] The fiber optic design for the ultra-miniature modular silicon photonic gyroscope is on the same side, meaning that the single fiber of the silicon photonic integrated device, the input single fiber of the Y-waveguide phase modulator, and the fiber loop pigtail are all on the same side of the sensing head module (side A of the sensing head module or side B of the integrated optical path module). This same-side design can effectively avoid fiber threading problems inside the fiber structure, which not only simplifies the optical path assembly process but also avoids reliability problems caused by imperfect assembly processes of multiple modules.

[0065] Furthermore, the integrated optical path module and integrated circuit module of the ultra-miniature modular silicon photonic gyroscope adopt a plug-in design. Two 15mm*2mm*8mm male connectors are designed on the integrated circuit module, and two female connectors of the same size are designed on the drive control circuit. Two 18mm*3mm arc-shaped grooves are cut on the second connecting plate of the upper housing to facilitate connector passage. The connector interface is defined as power supply, detector output, modulation signal, and temperature sensor pins, facilitating signal transmission between the drive control circuit and the integrated circuit module. The plug-in design avoids the use of flexible ribbon cables between two circuit boards, reducing board manufacturing costs. Moreover, compared with the traditional on-board soldering method for signal lines, it has superior signal transmission characteristics and avoids electromagnetic interference to the power supply and signal lines.

[0066] Furthermore, the ultra-miniature modular silicon photonic gyroscope achieves external connection through a specially designed ultra-miniature sealed insulator connector, the insulator connector structure being as follows: Figure 7 As shown, it has 7 glass insulator pins. Due to the amorphous structure of the insulator, it has ideal insulation performance. The pins are made of iron-nickel-cobalt glass-sealed alloy, which has good electrical performance and impact resistance. Its airtightness is also superior to that of insulator connectors made of other materials (such as PTFE). The design leakage rate is less than 1*10. -8 Pa·m 3 / S, insulation resistance ≥1000M ohms, dielectric withstand voltage higher than 200V, and can operate stably in the range of -55℃~125℃. The inductor connector has 7 pins, of which pins 1-3 are designed as power supply and ground pins (±VCC, GND), and pins 4-7 are designed as data differential output pins DO+ and DO- (expandable to include command transmission pins DI+ and DI-). By adopting a differential design to match the differential output level of 422, and adopting an anti-reverse insertion design, that is, using a layout of 3 or 4 pins, with different spacing between each group of pins, it effectively avoids gyroscope damage caused by reverse insertion of the connector.

[0067] As another aspect of the present invention, an automated and efficient assembly method for an ultra-miniature modular silicon photonic gyroscope is provided, the specific process steps of which are as follows:

[0068] (1) Ring bonding:

[0069] A robotic arm is used to grasp the fiber optic loop, reducing the difficulty of robotic arm operation and protecting the flexible and fragile optical fiber. A layer of loop bonding adhesive is applied to the bottom side of the fiber optic loop using an adhesive applicator, and the fiber optic loop is bonded and fixed to the lower surface of the first connecting plate of the middle shell. The concave groove at the commutation point of the fiber optic loop on the lower surface of the first connecting plate needs to be precisely located with a positioning accuracy of ±1mm.

[0070] (2) Passing the looped pigtail through:

[0071] Manually thread the twin pigtails of the optical fiber loop through the side hole of the first connecting plate of the middle housing to the lower surface of the first connecting plate of the middle housing, and control the robot arm to grasp the middle housing and the lower housing for alignment and welding;

[0072] (3) Bonding of Y-waveguide phase modulator:

[0073] The robotic arm grasps the Y-waveguide phase modulator and places it on the upper surface of the first connecting plate of the middle shell. The Y-waveguide phase modulator concave groove located on the upper surface of the first connecting plate of the middle shell needs to be precisely located with a positioning accuracy of ±1mm. Glue is applied to the bottom side of the Y-waveguide phase modulator using a glue applicator to bond and fix it to the concave groove position on the upper surface of the first connecting plate of the middle shell.

[0074] (4) Optical fiber loop pigtail axis fixation:

[0075] The pigtail alignment process includes the following four steps:

[0076] ① Preparation of fixed-axis optical fiber:

[0077] Determine the reserved pigtail length (0.5-1m), remove the coating layer using a thermal stripping process, clean the pigtail cladding bonding surface after removal, and then cut the end face for subsequent end face observation.

[0078] ② Preparation of the auxiliary plates to be used: Clean the fixed-axis auxiliary plates, and pre-groove the auxiliary plates. Cleaning ensures that the bonding surfaces are clean and dry.

[0079] ③Fiber optic axis fixing: The stress axis of the fiber optic cable is determined by end face image recognition orientation technology. After recognition, UV glue is used to bond and fix the fiber optic cable to the liner.

[0080] ④ Fiber optic aging: High-temperature baking is used to further cure the adhesive, improve the bonding strength of the product and release the stress caused during the bonding process.

[0081] (5) Grinding the end face of the fiber optic loop pigtail:

[0082] Grinding the end face of the pigtail includes the following 5 steps:

[0083] ① Fiber optic bonding and fixing: Fix the fixed-axis fiber optic strips on the fixture and measure the height difference to ensure the accuracy of the grinding angle;

[0084] ② Assemble the grinding fixture: Assemble the pigtail patch onto the fixed base. At this time, the fiber loop is located inside the lower housing to ensure no damage during the grinding and polishing process;

[0085] ③ Grinding: The grinding fixture tests the grinding pressure, and grinding liquid is dripped on to remove a certain amount of thinning material;

[0086] ④ Polishing: The polishing pressure is tested using a grinding fixture, and polishing liquid is dripped on to perform optical nano-level polishing on the end face;

[0087] ⑤ End face inspection: Use a microscope to inspect the end face.

[0088] (6) The two output ends of the Y-waveguide phase modulator are directly coupled to the fiber loop pigtail:

[0089] Direct coupling of pigtails includes the following 5 steps:

[0090] ① Material cleaning: This process mainly involves wiping and cleaning the surfaces to be bonded to ensure the reliability of subsequent bonding, including the two output surfaces of the Y-waveguide phase modulator and the two substrate surfaces of the fiber loop pigtail.

[0091] ② Coarse coupling of the two pads of the fiber loop pigtail: The two pads of the fiber loop pigtail are used to receive light by multimode fiber or detector. The two pads of the fiber loop pigtail are automatically adjusted to maximize the output optical power. In this process, auxiliary detection measures are used to ensure that the surfaces of the two pads of the fiber loop pigtail are horizontal with the two output end faces of the Y waveguide phase modulator.

[0092] ③ Dispensing and curing: After the parameters meet the standards, dispensing and curing are performed on both ends.

[0093] (7) Fixing of silicon photonic integrated devices:

[0094] The silicon photonic integrated device is held by a robotic arm and soldered to the drive control circuit. The four screws of the silicon photonic integrated device and the four screws of the drive control circuit are tightened to the lower surface of the second connecting plate of the upper housing with an electric screwdriver. Before tightening with the electric screwdriver, a layer of thread-locking adhesive is applied to the threaded holes of the screws.

[0095] (8) Fixed-length fusion splicing of single fiber in silicon photonic integrated devices and single fiber in Y-waveguide phase modulators:

[0096] The upper housing is held by a robotic arm, so that the integrated optical path module structure is close to the sensitive meter module. The two modules are 5-10mm apart. A fusion splicer is used to achieve single-fiber fusion splicing between the silicon photonic integrated device pigtail and the Y waveguide phase modulator. Note that the lengths of the two are cut as L1 and L2 respectively.

[0097] (9) Automated winding of pigtails:

[0098] Two optical loop pigtails, a silicon photonic integrated device output single fiber, and a Y-waveguide phase modulator input single fiber are automatically coiled on the upper surface of the first connecting plate of the middle shell.

[0099] The dispensing machine dispenses adhesive onto the multiple turns of optical fiber coiled on the upper surface of the first connecting plate of the central housing, and performs high-temperature aging treatment to stabilize the pigtail and reduce the impact of internal stress on the gyroscope performance.

[0100] (10) Welding and integration of the upper shell and the middle shell

[0101] The robotic arm is controlled to grasp and align the upper and middle housings, with a certain gap maintained between the sensitive meter module and the integrated optical path module. One end of the modulation line of the Y-waveguide phase modulator is soldered to the Y-waveguide modulation electrode, and the other end is slightly pulled and soldered to the modulation signal pin of the drive control circuit. The sensitive meter module and the integrated optical path module gradually approach each other until they are in contact (i.e., the silicon photonic integrated device contacts the Y-waveguide phase modulator), and then the upper and middle housings are sealed by laser welding.

[0102] (11) The upper shell and cover plate are welded together.

[0103] The integrated circuit module is picked up and directly connected to the integrated optical circuit module through a plug-in port. The integrated circuit module is installed on the upper surface of the second connecting plate of the upper housing; the upper housing and the cover plate are sealed by laser welding.

[0104] (12) Debugging the program function of integrated circuit module

[0105] Insert the FPGA download connector into the debugging interface of the integrated circuit module, and debug the gyroscope function of the FPGA in the integrated circuit module through program download on the host computer. During this process, monitor the detector output pin with an oscilloscope until a stable closed loop of the gyroscope signal is achieved.

[0106] (13) Debugging interface sealing

[0107] A circular encapsulation plate is placed at the debugging interface, and the circular encapsulation plate and the top of the structure are laser welded to achieve an integrated seal for the entire gyroscope.

[0108] The features described and / or illustrated above with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, and / or in combination with or in lieu of features in other embodiments.

[0109] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, components, or combinations thereof.

[0110] Many features and advantages of these embodiments are apparent from this detailed description, and therefore the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since many modifications and alterations will readily occur to those skilled in the art, the embodiments of the invention are not intended to be limited to the precise structures and operations illustrated and described, but rather to encompass all suitable modifications and equivalents falling within their scope.

[0111] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0112] The parts of this invention not described in detail are techniques known to those skilled in the art.

Claims

1. A miniature modular silicon photonic gyroscope, characterized by, The application relates to a super-small modular silicon photon gyroscope, which comprises a shell and a sensitive head module, an integrated optical path module and an integrated circuit module arranged in the shell from bottom to top. The shell comprises a lower shell, a middle shell, an upper shell and a cover plate which are connected in sequence from bottom to top, and the middle shell and the upper shell are respectively provided with a first connecting plate and a second connecting plate. The sensitive head module comprises a Y waveguide phase modulator and a fiber coil, the fiber coil is mounted on the lower surface of the first connecting plate of the middle shell, and the Y waveguide phase modulator is mounted on the upper surface of the first connecting plate of the middle shell. The integrated optical path module is mounted on the lower surface of the second connecting plate of the upper shell and comprises a silicon photon integrated device and a driving control circuit, the silicon photon integrated device is integrated with a light source, a detector and a coupler and is used for gyro light emission, light splitting, light combination and signal detection, and the driving control circuit is used for constant temperature control and current control of the silicon photon integrated device; single fiber fusion point connection is adopted between the silicon photon integrated device and the Y waveguide phase modulator. The integrated circuit module is mounted on the upper surface of the second connecting plate of the upper shell and is used for data modulation and demodulation and gyro communication; the integrated optical path module and the integrated circuit module are connected through a pair of plug-in connectors. The cover plate comprises an insulator connector and a debugging interface, the insulator connector is used for external power supply and data communication, and the debugging interface is used for FPGA program debugging of the silicon photon gyroscope. The optical fiber between the silicon photonics integrated device and the Y waveguide phase modulator includes two sections, a silicon photonics integrated device output section L 1. A Y waveguide phase modulator input section L 2, L 2. A length of 2 L 1, L 1. A length between 0.8-1.2m, the L 1, L 2. 45° axis fusion splicing; Two male connectors are arranged on the integrated circuit module, two female connectors matched with the male connectors in size are arranged on the driving control circuit, and two arc-shaped grooves are arranged on the second connecting plate of the upper shell for the connectors to pass through. Recessed grooves are arranged on the lower and upper surfaces of the first connecting plate of the middle shell for assembling the fiber coil and the Y waveguide phase modulator, and the first connecting plate of the middle shell comprises side holes through which tail fibers of the fiber coil pass.

2. The silicon photonics gyro as claimed in claim 1, wherein, Two output ports of the Y waveguide phase modulator are directly connected with two tail fibers of the fiber coil through optical fibers.

3. The silicon photonics gyro as claimed in claim 1, wherein, The silicon photon integrated device is welded to the driving control circuit through a 14-pin butterfly-shaped package.

4. The silicon photonics gyro as claimed in claim 1, wherein, The insulator connector adopts glass insulator pins, the pins adopt iron-nickel-cobalt glass sealing alloy, the glass insulator pins have seven pins, pins 1-3 are respectively power supply pins and ground pins, pins 4-7 are respectively data differential output pins DO+ and DO- and extendable sending command pins DI+ and DI-, the interval of the pins 1-3 is different from the interval of the pins 1-4, and the interval is used for anti-insertion function.

5. An automated and efficient assembly method of a miniature modular silicon photonic gyroscope, characterized in that, The super-small modular silicon photon gyroscope adopts the silicon photon gyroscope in any one of claims 1-4, and the method comprises the following steps: A mechanical hand is controlled to grab the fiber coil, brush adhesive on the fiber coil and bond the fiber coil to the lower surface of the first connecting plate of the middle shell; Two tail fibers of the fiber coil pass through the first connecting plate, a mechanical hand is controlled to grab the middle shell and align and weld the middle shell with the lower shell; A mechanical hand is controlled to grab the Y waveguide phase modulator, brush adhesive on the Y waveguide phase modulator and bond the Y waveguide phase modulator to the upper surface of the first connecting plate of the middle shell; Tail fibers of the fiber coil are fixed on an axis; Tail fiber auxiliary piece end faces of the fiber coil are ground. The two output end faces of the Y waveguide phase modulator are directly coupled with the fiber coil tail fiber; The mechanical hand is controlled to grab the silicon photon integrated device, and the silicon photon integrated device is welded with the driving control circuit and then installed on the lower surface of the second connecting plate of the upper shell; The mechanical hand is controlled to grab the upper shell close to the sensitive surface head module, and the tail fiber of the silicon photon integrated device output end is fusion spliced with the single fiber of the Y waveguide phase modulator input end; The fiber is coiled and glued; The mechanical hand is controlled to grab the upper shell and the middle shell, and then the upper shell and the middle shell are welded after being connected with the modulation line; The mechanical hand is controlled to grab the integrated circuit module and install the integrated circuit module on the upper surface of the second connecting plate of the upper shell, and then the cover plate is welded with the upper shell; The program function of the integrated circuit module is debugged. A round packaging piece is placed at the debugging interface, and welding and sealing are performed.

6. The method of claim 5, wherein, In the polishing process of the fiber coil, the grinding disc adopts an 8-shaped route follow-up.

7. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the computer program to realize the method of claim 5 or 6.

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