A co-packaged optical interconnect chip and applications thereof

Abstract

This invention discloses a three-dimensional waveguide glass chip based on CPO (Continuous Photonic Optical Array) with an integrated weak-reflection grating sensor array, relating to the field of integrated photonic sensors. The three-dimensional waveguide glass chip of this invention has a multi-core single-mode fiber array connection unit on the left end and a single-mode multi-core fiber optic connection unit on the right end, connected in the middle by a femtosecond laser direct-write multi-channel three-dimensional waveguide. The end directly connected to the optical chip also integrates a weak-reflection fiber grating for temperature measurement. Simultaneously, multiple three-dimensional waveguide glass chips connect to the optical chip, forming a grating temperature sensing array. The signal processing end uses host computer software to perform real-time online monitoring of optical loss and the periphery of the optoelectronic chip interface. This three-dimensional waveguide high-density optical connector with an integrated weak-reflection grating sensor array for CPO applications features low loss, low power consumption, high capacity, and multifunctionality, and can monitor chip temperature and interface quality using non-primary communication bands.

Description

Technical Field

[0001] This invention belongs to the field of integrated photonic sensors, and specifically relates to a three-dimensional waveguide glass chip based on CPO using an integrated weak reflection grating sensing array, which is mainly used for real-time monitoring of the temperature and docking quality of optical chips. Background Technology

[0002] Co-packaged optics (CPO) is a cutting-edge technology that co-packages optical engines and switching chips onto the same substrate. It breaks through the traditional pluggable optical module architecture, drastically shortening optical interconnect distances to the chip level, representing a fundamental revolution in data center interconnect technology. CPO relies on silicon photonics technology, high-density optical connectors (such as optical bridges and multi-core optical fibers), and advanced packaging processes to achieve a high degree of integration between the chip and the optoelectronic transceiver, ultimately forming an ultra-high-density, low-loss, mass-producible optoelectronic co-packaging solution.

[0003] A glass optical bridge fabricated using femtosecond laser 3D waveguide writing technology enables three-dimensional, ultra-high-density, high-performance, low-loss, and low-latency optical interconnection between chips in high-density optical connectors. Combined with fiber arrays (FA), fiber optic flexible circuits (FOFC), and multi-core fiber fan-in / fan-out (FI / FO) technology, it is a key component for overcoming the bottleneck of planar cabling. Although applicants such as Huawei (CN 114442221 A), Aidetech (CN116774350A), Jilin University (CN 118068481 A), and Meisu Optoelectronics (CN119805690A) have applied for related invention patents, these inventions primarily emphasize optical transmission applications, resulting in relatively simple functions that cannot meet the temperature monitoring requirements of lower-energy-consumption CPO chips.

[0004] Therefore, we propose a temperature sensing and monitoring system based on a three-dimensional waveguide glass chip and a weak reflection grating (WFBG) using CPO. Without affecting the communication bandwidth and optical power, the system utilizes a weak reflection fiber grating (WFBG) array in a non-primary communication band to meet the requirements for high-quality optical signal communication and exchange, while also obtaining key information such as chip temperature and docking quality in real time. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing a three-dimensional waveguide glass chip based on CPO and employing an integrated weak-reflection fiber Bragg grating sensor array, primarily for real-time monitoring of optical chip temperature and docking quality. This three-dimensional waveguide glass chip integrates a weak-reflection fiber Bragg grating array, satisfying the requirements of high-density connections, low power consumption, low loss, and low latency, while also possessing multifunctionality for online temperature monitoring and interface quality analysis.

[0006] This invention provides a three-dimensional waveguide glass chip based on CPO and employing an integrated weak reflection grating sensing array. The chip comprises: a glass substrate with a fan-in single-mode multi-core fiber structure and a fan-out multi-core fiber array structure on both sides; a three-dimensional waveguide structure with a three-dimensional waveguide structure inside the glass substrate for connecting the fan-in single-mode multi-core fiber structure and the fan-out multi-core fiber array structure; a weak reflection fiber grating integrated on the fan-in surface of the three-dimensional waveguide glass chip, multiple weak reflection fiber gratings forming a temperature sensing grating array when in use, the temperature sensing grating array being connected to a host computer, the host computer integrating a temperature demodulation scheme and a docking quality detection scheme.

[0007] Optionally, the three-dimensional waveguide glass chip adopts space division multiplexing technology; in the data exchange between the optical chip and the optical fiber communication, the three-dimensional waveguide glass chip is used as an optical bridge, with the fan-in side of the three-dimensional waveguide glass chip connected to the optical chip and the fan-out side connected to the optical fiber array or optical fiber flexible board; the three-dimensional waveguide glass chip is directly or indirectly connected to the optical chip and optical fiber in an integrated or pluggable manner.

[0008] Optionally, the fan-in single-mode multi-core fiber structure includes multiple communication input channels. The mode field diameter of each communication input channel is the same as the core mode field diameter of the standard single-mode fiber. The multiple communication input channels are distributed together in a circle with an end face diameter of less than 125 μm. The fan-in surface includes two polishing surfaces: 0° and 8°.

[0009] Optionally, the fan-out multi-core fiber array structure includes multiple communication output channels, each communication output channel having the same mode field diameter as the core mode field diameter of a standard single-mode fiber, and all communication output channels being at the same horizontal plane height. The spacing between adjacent communication output channels is the same, either 127 μm or 250 μm; the fan-out surface includes two grinding surfaces: 0° and 8°.

[0010] Optionally, the three-dimensional waveguide structure is fabricated using femtosecond laser direct writing technology. Each communication input channel and communication output channel consists of two straight waveguides and a three-dimensional spatial S-shaped curve waveguide in the middle. The key parameters such as the mode field diameter, transmission loss, and crosstalk of each channel are similar to the transmission parameters of standard single-mode optical fiber.

[0011] Optionally, the weak reflection fiber grating is etched into the three-dimensional waveguide structure using femtosecond laser writing technology. The center wavelength of the weak reflection fiber grating is located in a non-primary communication band, with a 3 dB bandwidth of less than 0.1 nm, a transmission notch depth of 0.5 dB, and a peak reflectivity of less than -30 dB. Each communication output channel is equipped with a weak reflection fiber grating, which is located near the fan-in surface of each communication output channel. The weak reflection fiber grating is used to measure the temperature of the connected optical chip and analyze the docking quality.

[0012] Optionally, the temperature sensing array forms a quasi-distributed sensing monitoring system to monitor the operating temperature of the optical chip and transmits the operating temperature of the optical chip to the host computer in real time. The host computer then plots the operating temperature as a temperature visualization color scale.

[0013] Optionally, the docking quality inspection scheme includes determining the docking status between the three-dimensional waveguide glass chip and the optical chip by analyzing the wavelength and power information of the weak reflection fiber Bragg grating; the docking status includes normal docking, long-distance docking, positive angle docking, and negative angle docking; when there are enough weak reflection fiber Bragg gratings, the docking quality inspection scheme can also determine the docking tilt angle.

[0014] Optionally, the single-mode multi-core structure of the signal input channel contains four, seven, or nineteen cores, which are connected to the fiber optic array.

[0015] Optionally, the single-mode multi-core structure of the signal output channel contains four, seven, or nineteen cores, which are connected to an optical fiber array.

[0016] This technical solution has the following advantages compared to traditional three-dimensional waveguide glass chips. 1. This invention uses space division multiplexing technology, which not only ensures high-density transmission of optical signals, but also integrates a temperature sensor array and a docking quality analysis module, and has the advantages of low loss, low power consumption, low latency, large capacity and multiple functions.

[0017] 2. This invention can monitor temperature changes around the chip, effectively reducing the energy consumption of traditional electrical sensors, and can be used to build a low-energy online chip temperature monitoring system.

[0018] 3. This invention adopts a weak reflection fiber grating array design, which can detect the temperature and docking quality at each interface with low loss and more flexibility by utilizing non-primary communication bands.

[0019] 4. This invention provides a demodulation scheme between optical power, docking deflection angle, and docking offset distance, which has dual-parameter demodulation capability.

[0020] 5. While traditional optical power measurements can monitor docking status, this significantly hinders the utilization of communication signals. This invention uses edge signals or low-power, non-primary communication band signals to analyze temperature and docking status, greatly reducing the bandwidth usage of communication channels.

[0021] This three-dimensional waveguide glass chip integrates a weakly reflective fiber Bragg grating array, which not only meets the requirements of high-density connection, low power consumption, low loss, and low latency, but also has the multi-functional advantages of online temperature monitoring and interface quality analysis. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a three-dimensional waveguide glass chip based on CPO and employing an integrated low-reflection grating sensing array. Figure 2a Left view of a three-dimensional waveguide glass chip; Figure 2b A top view of a three-dimensional waveguide glass chip; Figure 2c A schematic diagram of the overall dimensions of a three-dimensional waveguide glass chip in one possible embodiment; Figure 3 This is a schematic diagram illustrating the application of a three-dimensional waveguide glass chip in a CPO. Figure 4 This is a schematic diagram of the docking of a three-dimensional waveguide glass chip; Figure 5 This is a schematic diagram of the docking and demodulation scheme for a three-dimensional waveguide glass chip. Figure 6 A schematic diagram of a demodulation scheme for a weakly reflective fiber Bragg grating temperature sensing array. Figure 7 The diagram shows the structure of a single-mode multi-core structure containing four, seven, and nineteen cores for signal output and signal input channels. Figure 8a The simulation diagram shows the relationship between transmission loss and docking distance. Figure 8b The simulation diagram shows the relationship between transmission loss and docking angle. Figure 9 This is a sensitivity linear fit plot showing the relationship between transmission loss and docking distance and docking angle.

[0023] In the diagram: 1. Fan-out surface; 2. Four-channel fan-out; 3. Three-dimensional waveguide structure; 4. Weakly reflective fiber optic grating; 5. Fan-in surface; 6. Four-channel fan-in; 7. Single-mode multi-core structure; 8. Glass substrate; 9. Straight waveguide region; 10. S-shaped waveguide; 11. Optical chip; 12. Three-dimensional waveguide glass chip; 13. Fiber optic array or fiber optic flexible board; 14. Sensing point of weakly reflective grating array; 15. Temperature sensing area of ​​weakly reflective grating array; 16. Computer signal processing; 17. Temperature monitoring window of host computer software; 18. Temperature visualization. 19. Color scale diagram; 20. Temperature color contrast bar; 21. Side view of glass chip channel 1 and channel 2; 22. Weak reflection sensing grating; 23. Side view of optoelectronic chip channel 1 and 2; 24. Normal distance docking; 25. Long distance docking; 26. Positive angle docking; 27. Negative angle docking; 28. Four-core fan inlet; 29. ​​Four-core fan outlet; 30. Seven-core fan inlet; 31. Seven-core fan outlet; 32. Nineteen-core fan inlet; 33. Nineteen-core fan outlet; 34. Channel 1; 35. Channel 2; 36. Channel 3; 37. Channel 4. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this is not intended to limit the scope of the invention.

[0025] Example: In this embodiment, the three-dimensional waveguide glass chip 12 based on CPO and employing an integrated weak reflection grating sensing array includes a glass substrate 8. A fan-out single-mode multi-core fiber structure 2 and a fan-out multi-core fiber array structure 6 are disposed on both sides of the glass substrate 8. A three-dimensional waveguide structure 3 is disposed inside the glass substrate 8 to connect the fan-out single-mode multi-core fiber structure 2 and the fan-in multi-core fiber array structure 6. A weak reflection fiber grating 4 is integrated on the fan-in surface 5 of the three-dimensional waveguide glass chip 12. Multiple weak reflection fiber gratings 4 form a temperature sensing grating array when in use. The temperature sensing grating array is connected to a host computer, which integrates a temperature demodulation scheme and a docking quality detection scheme.

[0026] The glass substrate 8 is primarily made of high-purity fused silica glass or borosilicate glass, employing a space-division multiplexing (SDM) technology. The three-dimensional waveguide glass chip 12 includes a three-dimensional waveguide structure 3 integrating a weakly reflective fiber Bragg grating 4, serving as an optical bridge in high-capacity data exchange between the optical chip 11 and the optical fiber 13. The fan-in surface 5 of the three-dimensional waveguide glass chip 12 connects to the optical chip 11, and the fan-out surface 1 connects to the fiber array or flexible fiber optic plate 13. The three-dimensional waveguide glass chip 12 utilizes both integrated and pluggable designs, directly or indirectly connecting the optical chip 11 and the fiber array or flexible fiber optic plate 13.

[0027] The three-dimensional waveguide structure 3 on the glass substrate 8 is fabricated using femtosecond laser direct writing technology. The main core process parameters include the multi-scan strategy, the scanning path function, and the beam modulation scheme. Each channel consists of two straight waveguide regions 9 and an S-shaped waveguide 10 with a three-dimensional spatial S-shaped (Sigmoid function) curve in the middle. The key parameters of each channel, such as the mode field diameter, transmission loss, and crosstalk, are similar to the transmission parameters of standard single-mode optical fiber.

[0028] The weakly reflective fiber grating 4 integrated in the three-dimensional waveguide structure 3 is also etched point-by-point using a femtosecond laser. Its center wavelength is located in a non-primary communication band, with a 3 dB bandwidth of less than 0.1 nm, a transmission notch depth of 0.5 dB, and a corresponding peak reflectivity of less than -30 dB. Each channel is equipped with a weakly reflective fiber grating 4, located near the fan-in face 5 of each channel, for measuring the temperature and docking quality of the optical chip 11.

[0029] Temperature measurement process of optical chip 11: Because the weakly reflective fiber Bragg grating 4 is located close to the optical chip 11, it can obtain the reflection or transmission spectrum of the signal light during communication, which can be used for the analysis of temperature sensing signals. Specifically, the relationship between the wavelength of the weakly reflective fiber Bragg grating 4 and temperature is as follows: (1); in The center wavelength of the fiber grating. This is the offset of the center wavelength. The change in ambient temperature, thermo-optical coefficient coefficient of thermal expansion When the temperature changes, the heat from the optical chip 11 is rapidly transferred to the interface, and the center wavelength of the weakly reflective fiber grating 4 will change accordingly. The mapping between wavelength and temperature can be completed using the above formula.

[0030] Since the present invention has WFBG in each channel, the temperature data of multiple interfaces of the optical chip 11 are averaged and calibrated to obtain the temperature change value around the optical chip 11.

[0031] Docking quality measurement process: By simulating the relationship between transmission loss and docking angle and docking distance using waveguide simulation software, a linear relationship between the two can be observed. Therefore, the core expression of the docking quality testing scheme can be written as follows: (2); in The optical power for perfect alignment. This represents the change in optical power. This represents the change in the angle between the two mating surfaces. This represents the change in the straight-line distance between the mating surfaces. and The docking angle deflection coefficient and docking distance offset coefficient need to be measured according to the actual docking process.

[0032] The cross-sensitive decoupling equation for the docking is: (3); in and The optical power variation values ​​of weakly reflective fiber gratings 1 and 2 and The docking angle sensitivity coefficients for WFBG1 and WFBG2 are given. and This refers to the docking distance sensitivity coefficients of WFBG1 and WFBG2. By calibrating the docking angle sensitivity coefficients and docking distance sensitivity coefficients of WFBG1 and WFBG2 respectively, and then obtaining the power change values ​​of WFBG1 and WFBG2, the values ​​of deflection angle and offset distance can be obtained.

[0033] Based on the actual optical chip 11 docking end face size requirements, products with more channels can be designed, extending to multi-core fiber arrays, including four-core, seven-core, nineteen-core or more core fan-in fan-out end face structures, to obtain greater capacity, more accurate end face temperature sensing data and docking status analysis solutions.

[0034] Reference Figure 1 The three-dimensional waveguide glass chip based on CPO with integrated weak reflection grating sensing array has a basic structure including a fan-out surface 1, a fan-out four-channel 2, a three-dimensional waveguide structure 3, a weak reflection fiber grating 4, a fan-in surface 5, a fan-in four-channel 6, a single-mode multi-core structure 7, and a glass substrate 8.

[0035] In this embodiment, the fan-out four-channel 2 consists of four standard single-core single-mode optical fibers spaced 127 μm or 250 μm apart, with the rear end mainly connected to an optical fiber array or a flexible optical board. The fan-in single-mode multi-core fiber structure 6 is a single-mode multi-core fiber structure. Within a circumference of 62.5 μm radius on the fan-in surface 5, there are four standard single-mode fiber core interfaces arranged in a rectangular pattern with a mode field diameter of 9-10 μm and spaced 40 μm apart. In the three-dimensional waveguide structure 3 connecting the two, there are four weakly reflective fiber Bragg gratings 4 at the connection end between the fan-in surface 5 and the optical chip 11, used for measuring the temperature at the interface and analyzing the connection quality.

[0036] Figure 1The three-dimensional waveguide glass chip 12 is fabricated using femtosecond laser direct writing technology. The writing sequence is as follows: first, the left-end straight waveguide is written, then the S-shaped waveguide 10 is written, followed by the right-end straight waveguide, and finally, the process returns to the left end to fabricate the weak reflection fiber grating 4. After completing the above process, the remaining three-dimensional waveguide structures 3 and weak reflection fiber gratings 4 are processed in a cyclical manner. Since the S-shaped function expressions of the four waveguides are all different, appropriate adjustments need to be made based on their size, position, length, bending radius, and maximum tolerance for loss.

[0037] Reference Figures 2a-2c The overall dimensional design scheme of the three-dimensional glass waveguide chip 12 is presented. All annotations and dimensions are in millimeters. Figure 2a and Figure 2b The left and top views of the three-dimensional waveguide glass chip 12 are shown. Figure 2c The overall size of the exemplary three-dimensional waveguide glass chip 12 is shown. The example is a regular cuboid of 12mm*4mm*1mm, with straight waveguides at both ends of 0.5mm in length and S-shaped waveguides of 11mm in length. Smaller structures can also be designed.

[0038] In the waveguide path design, the fan-in and fan-out interfaces at both ends are straight waveguides, and the middle is connected by an S-shaped waveguide 10 with an S-shaped function bend. The specific expression in this case is: (4); in For the Sigmoid function, This is the difference parameter between the upper and lower smooth edges of the S-curve. is the steepness parameter of the curve. The parameter is the center-symmetric position of the curve. The starting position parameter of the lower edge of the curve.

[0039] Reference Figure 3 The specific application scheme of the present invention is as follows: the fan-in end of the three-dimensional waveguide glass chip 12 is connected to the optical chip 11, and the fan-out end is connected to the fiber array or fiber flexible plate 13. There are weak reflection grating array sensing points 14 near the interface between the three-dimensional waveguide glass chip 12 and the optical chip 11. In this embodiment, the four WFBGs are arranged in a regular rectangular pattern, with different center wavelengths, and are located in non-main communication bands. The 3 dB bandwidth is less than 0.1 nm, the transmission notch depth is 0.5 dB, and the peak reflectivity is less than -30 dB.

[0040] Because multiple three-dimensional waveguide glass chips 12 are connected to the optical chip 11, a weakly reflective grating array temperature sensing region 15 is formed around the optoelectronic chip 11. During the exchange of optoelectronic signals, the sensing signal outside the communication bandwidth is transmitted to the host computer through a computer signal processing process, and then mapped and converted into a temperature visualization color scale map 18. Through the temperature color contrast bar 19, the software engineer can obtain the intuitive temperature parameters of the optical chip 11 in real time.

[0041] The linear relationship between temperature change and wavelength shift can be obtained by formula (1). The demodulation scheme of fiber optic grating is a basic technology in the industry, and the specific process will not be described in detail.

[0042] Reference Figure 6 The transmission power spectra of four cascaded weakly reflective fiber Bragg gratings are presented. We can see that when the temperature rises, the center wavelength of the fiber Bragg grating (FBG) shifts towards longer wavelengths, and when the temperature falls, the center wavelength of the FBG shifts towards shorter wavelengths.

[0043] Reference Figure 4 In addition to temperature sensing, this invention can also monitor two key parameters of multi-core coupling: docking distance and docking angle. Figure 4 The docking side view of the three-dimensional waveguide glass chip channel and the optical chip channel is given, showing four common docking situations, from left to right: normal distance docking 23, relatively far distance docking 24, positive angle docking 25, and negative angle docking 26.

[0044] Reference Figure 5 In the diagram, fiber Bragg gratings FBG1 and FBG2 correspond to the weak reflection fiber Bragg grating 4 (WFBG1) in channel 1 (33) and the weak reflection fiber Bragg grating 4 (WFBG2) in channel 2 (34), respectively. If the connection is at a normal distance (23), the minimum power points at the transmission troughs of WFBG1 and WFBG2 should be roughly the same; for a longer distance (24), the minimum power points at the transmission troughs of WFBG1 and WFBG2 will decrease simultaneously; for a positive angle connection (25), the minimum power points at the transmission troughs of WFBG1 and WFBG2 will decrease simultaneously, with WFBG2 decreasing more; for a negative angle connection (26), the minimum power points at the transmission troughs of WFBG1 and WFBG2 will decrease simultaneously, with WFBG1 decreasing more. By observing the power changes in the transmission spectra of FBG1 and FBG2, the four connection scenarios can be distinguished.

[0045] To verify the linear fitting relationship between the transmission power, docking distance, and docking angle in formula (2), we simulated the power variation for docking distances of 15-45 μm, interval steps of 5 μm, docking angles of 0.4-0.7 degrees, and interval steps of 0.1 degrees.

[0046] Referring to Figure 8, a simulation diagram of the transmission power of a two-dimensional waveguide splicing of dual-core optical fibers using the wavenumber envelope method and Rsoft software is presented. The key global parameters of the simulation model are: background refractive index 1.45, core refractive index 1.452, core diameter 9 μm, transmission wavelength 1550 nm, lower splicing fiber length 100 μm, and upper splicing fiber length 500 μm.

[0047] Reference Figure 8a Simulation graphs of fiber optic cable transmission power are presented for a docking angle of 0° and docking distances of 15 μm, 25 μm, 35 μm, and 45 μm. When the distance is less than 10 μm, the transmission power is greater than 99%, which can be considered a perfect docking. (Refer to...) Figure 8b Simulation diagrams of fiber optic cable transmission power at docking distances of 10 μm and docking angles of 0.4°, 0.5°, 0.6°, and 0.7° are presented. (Refer to...) Figure 8a and Figure 8b The simulation results show that the transmitted power decreases as the docking distance increases, and similarly, it also decreases as the docking angle increases.

[0048] Reference Figure 9 The linear fitting results for two cases are presented, with both having a goodness of fit greater than 0.99. When the transmitted power is less than 93%, i.e., greater than 0.3 dB loss, according to the People's Republic of China Communications Industry Standard YDT+926.2-2023, the loss of 2-4 core multi-core fiber optic connectors should be less than 0.3-0.35 dB. The simulation results for lower power are not elaborated here.

[0049] Reference Figure 9 Since the two have different sensitivities, a docking cross-sensitivity decoupling equation can be used: (3); in and These are the optical power changes for WFBG1 and WFBG2, respectively. and The docking angle sensitivity coefficients for WFBG1 and WFBG2 are given. and This refers to the docking distance sensitivity coefficients of WFBG1 and WFBG2. By calibrating the docking angle sensitivity coefficients and docking distance sensitivity coefficients of WFBG1 and WFBG2 respectively, and then obtaining the power change values ​​of WFBG1 and WFBG2, the values ​​of deflection angle and offset distance can be obtained.

[0050] Reference Figure 7The fan-in face 5 and fan-out face 1 of this invention can have multiple cores, as illustrated in the figures: four-core fan-in face 27 and four-core fan-out face 28; seven-core fan-in face 29 and seven-core fan-out face 30; nineteen-core fan-in face 31 and nineteen-core fan-out face 32. Based on this, more cores and lower crosstalk multi-core fiber can be developed by combining channel fiber technology.

[0051] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A three-dimensional waveguide glass chip based on CPO and employing an integrated low-reflection grating sensing array, characterized in that, include: A glass substrate, wherein a fan-in single-mode multi-core fiber structure and a fan-out multi-core fiber array structure are provided on both sides of the glass substrate; A three-dimensional waveguide structure is provided inside the glass substrate for connecting the fan-in single-mode multi-core fiber structure and the fan-out multi-core fiber array structure. The fan-in surface of the three-dimensional waveguide glass chip is integrated with a weak reflection fiber grating. When multiple weak reflection fiber gratings are used, they form a temperature sensing grating array. The temperature sensing grating array is connected to a host computer, which integrates a temperature demodulation scheme and a docking quality detection scheme.

2. The three-dimensional waveguide glass chip according to claim 1, characterized in that, The three-dimensional waveguide glass chip adopts space division multiplexing technology; The three-dimensional waveguide glass chip is used as an optical bridge in the data exchange between the optical chip and optical fiber communication. The fan-in face of the three-dimensional waveguide glass chip is connected to the optical chip, and the fan-out face is connected to the optical fiber array or optical fiber flexible plate. The three-dimensional waveguide glass chip is directly or indirectly connected to the optical chip and optical fiber using an integrated connection structure or a pluggable connection structure.

3. The three-dimensional waveguide glass chip according to claim 1, characterized in that, The fan-in single-mode multi-core fiber structure includes multiple communication input channels. The mode field diameter of each communication input channel is the same as the core mode field diameter of a standard single-mode fiber. The multiple communication input channels are distributed in a circle with an end face diameter of less than 125 μm. The fan-in surface includes two polished surfaces: 0° and 8°.

4. The three-dimensional waveguide glass chip according to claim 3, characterized in that, The fan-out multi-core fiber array structure includes multiple communication output channels. The mode field diameter of each communication output channel is the same as the core mode field diameter of a standard single-mode fiber. All communication output channels are at the same horizontal plane height. The spacing between adjacent communication output channels is the same, which is 127 μm or 250 μm. The fan-out surface includes two polishing surfaces: 0° and 8°.

5. The three-dimensional waveguide glass chip according to claim 4, characterized in that, The three-dimensional waveguide structure is fabricated using femtosecond laser direct writing technology. Each of the communication input channels and the communication output channels consists of two straight waveguides and a three-dimensional S-shaped curve waveguide in the middle. The key parameters of each channel, such as mode field diameter, transmission loss, and crosstalk, are similar to the transmission parameters of standard single-mode optical fiber.

6. The three-dimensional waveguide glass chip according to claim 5, characterized in that, The weakly reflective fiber Bragg grating is inscribed in the three-dimensional waveguide structure using femtosecond laser writing technology. The center wavelength of the weakly reflective fiber Bragg grating is located in a non-primary communication band, with a 3 dB bandwidth of less than 0.1 nm, a transmission notch depth of 0.5 dB, and a peak reflectivity of less than -30 dB. Each of the communication output channels is equipped with one of the weakly reflective fiber Bragg gratings, which is located near the fan-in surface of each communication output channel. The weakly reflective fiber Bragg grating is used to measure the temperature of the connected optical chip and analyze the docking quality.

7. The three-dimensional waveguide glass chip according to claim 1, characterized in that, The temperature sensing array forms a quasi-distributed sensing system to monitor the operating temperature of the optical chip and transmits the operating temperature of the optical chip to the host computer in real time. The host computer then plots the operating temperature as a temperature visualization color scale.

8. The three-dimensional waveguide glass chip according to claim 1, characterized in that, The docking quality detection scheme includes determining the docking status between the three-dimensional waveguide glass chip and the optical chip by analyzing the wavelength and power information of the weak reflection fiber grating. The docking states include normal docking, long-distance docking, positive angle docking, and negative angle docking; when the number of weak reflection fiber Bragg gratings is sufficient, the docking quality detection scheme can also determine the docking tilt angle.

9. The three-dimensional waveguide glass chip according to claim 3, characterized in that, The single-mode multi-core structure of the signal input channel contains four, seven, or nineteen cores, which are connected to a single-mode multi-core optical fiber.

10. The three-dimensional waveguide glass chip according to claim 4, characterized in that, The single-mode multi-core structure of the signal output channel contains four, seven, or nineteen cores and is connected to an optical fiber array.

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