800G DR8 silicon optical engine with small channel optical power difference and coupling method
By adjusting the coupling sequence and lens fixing method of the silicon photonics engine, the problem of large differences in channel optical power in traditional silicon photonics engines was solved, and the channel optical power difference was controlled within 0.5dB, meeting the application requirements.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-29
- Publication Date
- 2026-04-07
AI Technical Summary
The channel optical power difference of traditional 800G DR8 silicon photonics engines is difficult to control within 1dB, which makes it impossible to meet application requirements.
A novel coupling method is employed, which first couples the fiber array to the silicon photonic chip, then couples a collimating lens between the laser chip and the optical isolator, and finally adjusts the fixed order of the converging lens according to the optical power value during the converging lens process, thereby controlling the channel optical power difference to within 0.5dB.
The optical power difference between the eight channels was kept within 0.5dB, meeting the application requirements of the 800G DR8 silicon photonics engine.
Smart Images
Figure CN121806208A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of optical engine technology, specifically to an 800G DR8 silicon photonic engine with small channel optical power differences and a coupling method. Background Technology
[0002] The structure of a traditional 800G DR8 silicon photonics engine is as follows: Figure 1 As shown, it includes: The system comprises a silicon photonics chip, an optical fiber array, an optical isolator, two laser chips, two collimating lenses, and two converging lenses. The silicon photonics chip has two input waveguides and eight output waveguides. The two input waveguides are the input waveguides for the first and second channels, respectively. The eight output waveguides are distributed sequentially as the output waveguides for the first, second, third, fourth, fifth, sixth, seventh, and eighth channels. The input waveguide of the first channel is coupled to the output waveguides of the first, second, third, and fourth channels, respectively. The input waveguide of the second channel is coupled to the output waveguides of the fifth, sixth, seventh, and eighth channels, respectively. The input waveguide of the first channel in the silicon photonics chip is coupled to one MPD (Multi-Purpose Detector), and 1% to 3% of the light from the input waveguide of the first channel is directed to the MPD, for example, 2%. Similarly, the input waveguide of the second channel in the silicon photonics chip is coupled to one MPD, and 1% to 3% of the light from the input waveguide of the second channel in the silicon photonics chip is directed to the MPD, for example, 2%. The first laser chip is coupled to the input waveguide of the first channel in the silicon photonic chip after passing through a collimating lens, an optical isolator, and a converging lens in sequence. The second laser chip is coupled to the input waveguide of the second channel in the silicon photonic chip after passing through a collimating lens, an optical isolator, and a converging lens in sequence. The first laser chip is fixed on a ceramic heat sink, and the second laser chip is also fixed on a ceramic heat sink. The optical isolator is preferably a dual optical isolator. The fiber optic array is coupled to the output waveguide of the silicon photonic chip. Specifically, the first, second, third, fourth, fifth, sixth, seventh, and eighth channels of the fiber optic array are coupled to the output waveguides of the first, second, third, fourth, fifth, sixth, seventh, and eighth channels of the silicon photonic chip, respectively. The tilt angle of the output waveguide in the silicon photonic chip is the same as the tilt angle of the end face in the fiber optic array. For example, a common scenario is that the tilt angle of the output waveguide in the silicon photonic chip is 8°, the tilt angle of the end face in the fiber optic array is 8°, and the output wavelength of each channel in the fiber optic array is 100G. Since there are 8 channels, 8 × 100G = 800G.
[0003] The coupling method for the 800G DR8 silicon photonics engine is as follows: S10. First, attach and fix the silicon photonics chip, the first laser chip, the second laser chip, and the optical isolator. S20. A collimating lens is coupled between the laser chip and the optical isolator in the first channel, and a converging lens is coupled between the input waveguide and the optical isolator in the first channel. When the photocurrent value of the MPD coupled to the input waveguide of the first channel in the silicon photonic chip is the maximum, the collimating lens and the converging lens are fixed. Then, a collimating lens is coupled between the laser chip and the optical isolator in the second path, and a converging lens is coupled between the input waveguide and the optical isolator in the second channel. When the photocurrent value of the MPD coupled to the input waveguide of the second channel in the silicon photonic chip is the maximum, the collimating lens and the converging lens are fixed (S20 can also couple the second path first and then the first path). S30. First, connect an external optical power meter to the pigtail of each channel of the fiber optic array. Then, couple the fiber optic array to the silicon photonic chip. When the optical power value of each channel is at its maximum, fix the fiber optic array. The coupling process is as follows: Figure 2 As shown.
[0004] In this coupling scheme, due to the patching errors of the laser chip, optical isolator, and silicon photonics chip, as well as the material differences inherent in the laser chip, optical isolator, collimating lens, converging lens, and fiber array (the optical power difference between each channel of the fiber array is very small, basically less than 0.25dB, that is, the insertion loss of all 8 channels is less than 0.25dB), it is ultimately difficult to control the optical power difference between the eight channels within 1dB. It is basically greater than 1dB, or even close to 2dB. Due to the large difference in optical power between each channel of the 800G DR8 silicon photonics engine, it is impossible to meet the expected application requirements. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide an 800G DR8 silicon photonic engine and coupling method with small channel optical power differences, so as to overcome the shortcomings of the prior art.
[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences includes the following steps: S10. Fabricate a silicon photonic chip that couples the first and second channel input waveguides and the first and eighth channel output waveguides to an MPD. S20. The silicon photonics chip, the first laser chip, the second laser chip, and the optical isolator are fixed in a surface mount manner. S30. The fiber array is coupled to the silicon photonic chip using an active coupling method; S40. A collimating lens is coupled and fixed between the laser chip and the optical isolator in the first and second paths, respectively. S50. Connect the pigtails of each channel of the fiber array to an external optical power meter. Couple the converging lens in the first channel in a non-fixed manner and record the optical power values of CH1, CH2, CH3, and CH4. Assume that the minimum and maximum optical power values of CH1 to CH4 are G1 and G2, respectively. Then move the converging lens to the second channel and couple it in a non-fixed manner. Record the optical power values of CH5, CH6, CH7, and CH8. Assume that the minimum and maximum optical power values of CH5 to CH8 are G3 and G4, respectively. S60. Compare the sizes of G1, G2, G3 and G4. If the smallest value is found, first couple and fix the converging lens of that path. Then defocus and couple and fix the converging lens of the other path. Control the difference between the maximum and minimum values of G1, G2, G3 and G4 to be 0 to 0.5 dB.
[0007] The beneficial effects of this invention are: In this coupling method, since the output waveguide of the first channel in the silicon photonics chip is coupled to an MPD, and the output waveguide of the eighth channel in the silicon photonics chip is coupled to an MPD, the fiber array can be coupled first, followed by the collimating lens. When finally coupling the focusing lens, the focusing lens is not fixed initially. Instead, the focusing lens is coupled once in each of the two paths, and the optical power values are compared. The focusing lens of the path with the lowest optical power value is coupled and fixed first. Then, the focusing lens of the other path is defocused and fixed. By controlling the difference between the maximum and minimum optical power values in the eight channels to be within 0 to 0.5 dB, the optical power difference of the eight channels can be guaranteed to be within 0.5 dB, so that the 800G DR8 silicon photonics engine can meet the expected application requirements.
[0008] Based on the above technical solution, the present invention can be further improved as follows.
[0009] Furthermore, in the silicon photonics chip, the input waveguide of the first channel directs 1% to 3% of the light to one MPD, and in the silicon photonics chip, the input waveguide of the second channel directs 1% to 3% of the light to one MPD.
[0010] Furthermore, in the silicon photonics chip, the output waveguide of the first channel directs 1% to 3% of the light to one MPD, and in the silicon photonics chip, the output waveguide of the eighth channel directs 1% to 3% of the light to one MPD.
[0011] Furthermore, S30 specifically refers to: First, connect an external light source to each pigtail of the fiber array. Then, couple the fiber array to the silicon photonics chip. When the photocurrent value of the MPD coupled to the output waveguide of the first channel in the silicon photonics chip and the photocurrent value of the MPD coupled to the output waveguide of the eighth channel in the silicon photonics chip are both at their maximum, fix the fiber array.
[0012] Furthermore, the output waveguides in the silicon photonics chip are tilted, and the end face of the fiber array is inclined. The tilt angle of the output waveguides in the silicon photonics chip is the same as the tilt angle of the end face in the fiber array.
[0013] Furthermore, the tilt angle of the output waveguide in the silicon photonics chip and the tilt angle of the end face in the fiber array are both 8°.
[0014] Furthermore, S40 specifically refers to: A collimating lens is coupled and fixed between the laser chip and the optical isolator in the first channel. The collimating lens is fixed when the photocurrent value of the MPD coupled to the input waveguide of the first channel in the silicon photonic chip is the maximum. A collimating lens is coupled and fixed between the laser chip and the optical isolator in the second path. The collimating lens is fixed when the photocurrent value of the MPD coupled to the input waveguide of the second channel in the silicon photonic chip is at its maximum.
[0015] Furthermore, the laser chips for the first and second channels are respectively fixed on a ceramic heat sink, the optical isolator is a dual optical isolator, and the output wavelength of each channel of the fiber array is 100G.
[0016] Furthermore, the S60 specifically refers to: Assuming G4 is the largest, if G1 < G2 < G3 < G4, then under this condition, first couple the converging lens of the first path, then defocus couple the converging lens of the second path, and let the difference between G4 and G1 be 0 to 0.5 dB. If G1 < G3 < G2 < G4, then under this condition, first couple and fix the first path converging lens, then defocus and couple and fix the second path converging lens, and make the difference between G4 and G1 0 to 0.5 dB. If G3 < G1 < G2 < G4, then under this condition, first couple and fix the second path converging lens, then defocus and couple and fix the first path converging lens, and make the difference between G4 and G3 0 to 0.5 dB.
[0017] Based on the above technical solution, the present invention also provides an 800G DR8 silicon photonic engine with small channel optical power differences, which is obtained by coupling using the above coupling method.
[0018] The further beneficial effect of adopting the above is that the optical power difference of the eight channels in the 800G DR8 silicon photonics engine is within 0.5dB, which can meet the expected application requirements. Attached Figure Description
[0019] Figure 1 This is a structural diagram of an 800G DR8 silicon photonics engine in the prior art; Figure 2 This is a flowchart of the coupling method for an 800G DR8 silicon photonic engine in the prior art; Figure 3 This is a flowchart of the first method for coupling 800G DR8 silicon photonics engine with small channel optical power differences in this invention; Figure 4 This is a second flowchart of the coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences in this invention; Figure 5 for Figure 3 The diagram shows the structure of an 800G DR8 silicon photonic engine with small channel optical power differences, formed by the coupling process shown. Figure 6 for Figure 4 The diagram shows the structure of an 800G DR8 silicon photonic engine with small differences in channel optical power, coupled by the process shown.
[0020] The attached diagram lists the components represented by each number as follows: 1. Silicon photonics chip, 110. Input waveguide, 120. Output waveguide, 130. MPD, 2. Fiber array, 3. Laser chip, 4. Optical isolator, 5. Collimating lens, 6. Converging lens, 7. Ceramic heat sink. Detailed Implementation
[0021] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.
[0022] Example 1 like Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, a coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences includes the following steps: S10. Fabricate a silicon photonic chip 1. The silicon photonic chip 1 has two input waveguides 110 and eight output waveguides 120 on the same side. The two input waveguides 110 are the input waveguides 110 of the first channel and the input waveguides 110 of the second channel, respectively. The eight output waveguides 120 are distributed sequentially as the output waveguides 120 of the first, second, third, fourth, fifth, sixth, seventh, and eighth channels, respectively. The input waveguide 110 of the first channel is coupled to the output waveguides 120 of the first, second, third, and fourth channels, respectively. The input waveguide 120 of the second channel is coupled to the output waveguides 120 of the second channel. Waveguide 110 is coupled to the output waveguides 120 of the fifth, sixth, seventh and eighth channels respectively. The input waveguide 110 of the first channel of the silicon photonic chip 1 is coupled to one MPD 130. The input waveguide 110 of the second channel of the silicon photonic chip 1 is coupled to one MPD 130. The output waveguide 120 of the first channel of the silicon photonic chip 1 is coupled to one MPD 130. The output waveguide 120 of the eighth channel of the silicon photonic chip 1 is coupled to one MPD 130. That is, the fabricated silicon photonic chip 1 has at least four MPD 130. S20. The silicon photonics chip 1, the first laser chip 3, the second laser chip 3, and the optical isolator 4 are fixed by surface mounting. The surface mounting method remains consistent with the existing technology. S30. The fiber array 2 is coupled to the silicon photonic chip 1 using an active coupling method; S40. A collimating lens 5 is coupled and fixed between the laser chip 3 and the optical isolator 4 in the first path, and a collimating lens 5 is coupled and fixed between the laser chip 3 and the optical isolator 4 in the second path. S50. Connect the pigtails of each channel of the fiber array 2 to an external optical power meter. Since the silicon photonic chip 1 has output waveguides 120 with channels 1, 2, 3, 4, 5, 6, 7, and 8, the fiber array 2 also has eight channels. Therefore, connect the pigtails of channels 1, 2, 3, 4, 5, 6, 7, and 8 of the fiber array 2 to an external eight-channel optical power meter. In a non-fixed manner (referring to the coupling focusing lens 6, where the focusing lens 6 is not fixed), the first-path coupling focusing lens 6 is coupled between the input waveguide 110 and the optical isolator 4 of the first channel in a non-fixed manner. The optical power values of CH1, CH2, CH3, and CH4 are recorded respectively, and it is assumed that the minimum and maximum optical power values of CH1 to CH4 are G1 and G2 respectively. The first-path coupling focusing lens 6 is located between the input waveguide 110 and the optical isolator 4 of the first channel. Since the first, second, third, and fourth optical fiber arrays 2 are... The fiber optic pigtails of each channel are connected to an external optical power meter. Therefore, the emitted light emitted by the laser chip 3 in the first channel can be coupled into the input waveguide 110 of the first channel in the silicon photonic chip 1 after passing through the collimating lens 5, the optical isolator 4, and the converging lens 6 in sequence. Then, it is distributed from the input waveguide 110 of the first channel to the output waveguides 120 of the first, second, third, and fourth channels. Finally, it is coupled into the first, second, third, and fourth channels of the fiber array 2, thereby enabling the detection of the optical power values of the signal light in CH1, CH2, CH3, and CH4. The converging lens 6 is then moved to the second path and coupled in a non-fixed manner. That is, the converging lens 6 is moved between the input waveguide 110 of the second channel and the optical isolator 4, and the converging lens 6 is coupled in a non-fixed manner. The optical power values of CH5, CH6, CH7, and CH8 are recorded respectively. It is assumed that the minimum and maximum optical power values of CH5 to CH8 are G3 and G4 respectively. Since the pigtails of the fifth, sixth, seventh, and eighth channels in the fiber array 2 are connected to external optical power meters, the emitted light emitted by the laser chip 3 in the second path can be coupled into the input waveguide 110 of the second channel in the silicon photonic chip 1 after passing through the collimating lens 5, the optical isolator 4, and the converging lens 6 in sequence. Then, it is split from the input waveguide 110 of the second channel to the output waveguides 120 of the fifth, sixth, seventh, and eighth channels, and then coupled into the fifth, sixth, seventh, and eighth channels in the fiber array 2. Thus, the optical power values of the signal light in CH5, CH6, CH7, and CH8 can be detected. S60. Compare the values of G1, G2, G3, and G4. If the value is the smallest, first couple and fix the converging lens 6 of that path, and then defocus and couple and fix the converging lens 6 of the other path. For example, if G1 is the smallest, first fix the converging lens 6 of the first path, and then defocus and couple and fix the converging lens 6 of the second path. If G3 is the smallest, first fix the converging lens 6 of the second path, and then defocus and couple and fix the converging lens 6 of the first path. Control the difference between the maximum and minimum values of G1, G2, G3, and G4 to be 0 to 0.5 dB.
[0023] Since the optical power difference between each channel of the fiber array 2 is less than 0.25dB, and the first, second, third, and fourth channels of the fiber array 2 share the same laser chip 3, the optical power difference between the first, second, third, and fourth channels of the fiber array 2 will not exceed 0.25dB. That is, the optical power difference between CH1, CH2, CH3, and CH4 will not exceed 0.25dB; similarly, the optical power difference between CH5, CH6, CH7, and CH8 will not exceed 0.25dB.
[0024] In this coupling method, since the output waveguide 120 of the first channel of silicon photonic chip 1 is coupled to an MPD 130, and the output waveguide 120 of the eighth channel of silicon photonic chip 1 is coupled to an MPD 130, during coupling, the fiber array 2 can be coupled first, then the collimating lens 5, and finally the converging lens 6. Instead of fixing the converging lens 6, the converging lens 6 is first coupled once in each of the two paths, and the optical power values are compared. The one with the smallest optical power value is the converging lens 6 of that path that is coupled and fixed first. Then, the other converging lens 6 is defocused and fixed. By controlling the difference between the maximum and minimum optical power values in the eight channels to be within 0 to 0.5 dB, the optical power difference of the eight channels can be guaranteed to be within 0.5 dB, so that the 800G DR8 silicon photonic engine can meet the expected application requirements.
[0025] Example 2 like Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, this embodiment is a further improvement on embodiment 1, as detailed below: In silicon photonic chip 1, the input waveguide 110 of the first channel directs 1% to 3% of the light to an MPD 130. For example, 2% of the light from the input waveguide 110 of the first channel of silicon photonic chip 1 is directed to an MPD 130. The 2% is just an example here, and the corresponding value can be selected within this range in actual application. Similarly, in silicon photonic chip 1, the input waveguide 110 of the second channel directs 1% to 3% of the light to an MPD 130. For example, 2% of the light from the input waveguide 110 of the second channel of silicon photonic chip 1 is directed to an MPD 130. The 2% is just an example here, and the corresponding value can be selected within this range in actual application.
[0026] Furthermore, in silicon photonic chip 1, the output waveguide 120 of the first channel directs 1% to 3% of the light to an MPD 130. For example, 2% of the output waveguide 120 of the first channel of silicon photonic chip 1 is directed to an MPD 130. The 2% figure is just an example here, and it can be selected within this range in actual applications. Similarly, in silicon photonic chip 1, the output waveguide 120 of the eighth channel directs 1% to 3% of the light to an MPD 130. For example, 2% of the output waveguide 120 of the eighth channel of silicon photonic chip 1 is directed to an MPD 130. The 2% figure is just an example here, and it can be selected within this range in actual applications.
[0027] Example 3 like Figure 3 , Figure 4 As shown, this embodiment is a further improvement on embodiment 1 or 2, as detailed below: S30 specifically refers to: First, connect an external light source to each of the pigtails of fiber array 2, that is, connect an external light source to the pigtails of the first, second, third, fourth, fifth, sixth, seventh, and eighth channels of fiber array 2. Then, couple fiber array 2 with silicon photonic chip 1, that is, couple the first, second, third, fourth, fifth, sixth, seventh, and eighth channels of fiber array 2 with the output waveguides 120 of the first, second, third, fourth, fifth, sixth, seventh, and eighth channels of silicon photonic chip 1 one by one. When the photocurrent value of MPD130 coupled to the output waveguide 120 of the first channel in silicon photonic chip 1, and when the photocurrent value of MPD130 coupled to the output waveguide 120 of the eighth channel in silicon photonic chip 1 is simultaneously at its maximum, fiber array 2 can be fixed.
[0028] Example 4 like Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, this embodiment is a further improvement on embodiment 1, 2, or 3, as detailed below: The output waveguide 120 in silicon photonic chip 1 is tilted, and the end face of fiber array 2 is inclined. The tilt angle of the output waveguide 120 in silicon photonic chip 1 is the same as the tilt angle of the end face in fiber array 2. For example, a common case is that the tilt angle of the output waveguide 120 in silicon photonic chip 1 is 8°, and the tilt angle of the end face in fiber array 2 is 8°. Of course, 8° is just an example, and in actual applications, it can be selected by floating around 8°.
[0029] Example 5 like Figure 3 , Figure 4 , Figure 5 , Figure 6As shown, this embodiment is a further improvement on any one of embodiments 1 to 4, as detailed below: S40 specifically refers to: A collimating lens 5 is coupled and fixed between the laser chip 3 and the optical isolator 4 in the first channel. When the photocurrent value of the MPD130 coupled with the input waveguide 110 of the first channel in the silicon photonic chip 1 is the maximum, the collimating lens 5 is fixed. Additionally, a collimating lens 5 is coupled and fixed between the laser chip 3 and the optical isolator 4 in the second path. When the photocurrent value of the MPD130 coupled to the input waveguide 110 of the second channel in the silicon photonic chip 1 is at its maximum, the collimating lens 5 is fixed.
[0030] Example 6 like Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, this embodiment is a further improvement on any one of embodiments 1 to 5, as detailed below: The first laser chip 3 is fixed on a ceramic heat sink 7, and the second laser chip 3 is also fixed on a ceramic heat sink 7. The optical isolator 4 is a dual optical isolator. The output wavelength of each channel of the fiber array 2 is 100G, and 8 channels × 100G = 800G. This part is still consistent with the existing technology.
[0031] Example 7 like Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, this embodiment is a further improvement on any one of embodiments 1 to 6, as detailed below: Assuming G4 is the largest, if G1 < G2 < G3 < G4, then under this condition, the first channel converging lens 6 is first coupled and fixed, and then the second channel converging lens 6 is defocused and coupled and fixed. That is, firstly, a converging lens 6 is coupled and fixed between the input waveguide 110 of the first channel and the optical isolator 4, and then a converging lens 6 is defocused and coupled and fixed between the input waveguide 110 of the second channel and the optical isolator 4, and the difference between G4 and G1 is 0 to 0.5 dB. If G1 < G3 < G2 < G4, then under this condition, the first channel converging lens 6 is first coupled and fixed, and then the second channel converging lens 6 is defocused and coupled and fixed. That is, firstly, a converging lens 6 is coupled and fixed between the input waveguide 110 of the first channel and the optical isolator 4, and then a converging lens 6 is defocused and coupled and fixed between the input waveguide 110 of the second channel and the optical isolator 4, and the difference between G4 and G1 is 0 to 0.5 dB. If G3 < G1 < G2 < G4, then under this condition, the second channel converging lens 6 is first coupled and fixed, and then the first channel converging lens 6 is defocused and coupled and fixed. That is, firstly, a converging lens 6 is coupled and fixed between the input waveguide 110 of the second channel and the optical isolator 4, and then a converging lens 6 is defocused and coupled and fixed between the input waveguide 110 of the first channel and the optical isolator 4, and the difference between G4 and G3 is 0 to 0.5 dB.
[0032] Example 8 like Figure 5 , Figure 6 As shown, an 800G DR8 silicon photonic engine with small channel optical power differences is obtained by coupling using the coupling method described in any of Examples 1 to 7.
[0033] The optical power difference between the eight channels in this 800G DR8 silicon photonics engine is within 0.5dB, which can meet the expected application requirements.
[0034] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.
Claims
1. A coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences, characterized in that, Includes the following steps: S10. Fabricate a silicon photonic chip that couples the first and second channel input waveguides and the first and eighth channel output waveguides to an MPD. S20. The silicon photonics chip, the first laser chip, the second laser chip, and the optical isolator are fixed in a surface mount manner. S30. The fiber array is coupled to the silicon photonic chip using an active coupling method; S40. A collimating lens is coupled and fixed between the laser chip and the optical isolator in the first and second paths, respectively. S50. Connect the pigtails of each channel of the fiber array to an external optical power meter. Couple the converging lens in the first channel in a non-fixed manner and record the optical power values of CH1, CH2, CH3, and CH4. Assume that the minimum and maximum optical power values of CH1 to CH4 are G1 and G2, respectively. Then move the converging lens to the second channel and couple it in a non-fixed manner. Record the optical power values of CH5, CH6, CH7, and CH8. Assume that the minimum and maximum optical power values of CH5 to CH8 are G3 and G4, respectively. S60. Compare the sizes of G1, G2, G3 and G4. If the smallest value is found, first couple and fix the converging lens of that path. Then defocus and couple and fix the converging lens of the other path. Control the difference between the maximum and minimum values of G1, G2, G3 and G4 to be 0 to 0.5 dB.
2. The coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences according to claim 1, characterized in that, In the silicon photonics chip, the input waveguide of the first channel directs 1% to 3% of the light to one MPD, and the input waveguide of the second channel directs 1% to 3% of the light to one MPD.
3. A coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences according to claim 1 or 2, characterized in that, In the silicon photonics chip, the output waveguide of the first channel directs 1% to 3% of the light to one MPD, and the output waveguide of the eighth channel of the silicon photonics chip directs 1% to 3% of the light to one MPD.
4. A coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences according to claim 1, 2, or 3, characterized in that, S30 specifically refers to: First, connect an external light source to each pigtail of the fiber array. Then, couple the fiber array to the silicon photonics chip. When the photocurrent value of the MPD coupled to the output waveguide of the first channel in the silicon photonics chip and the photocurrent value of the MPD coupled to the output waveguide of the eighth channel in the silicon photonics chip are both at their maximum, fix the fiber array.
5. The coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences according to claim 1, characterized in that, The output waveguides in the silicon photonic chip are tilted, the end face of the fiber array is inclined, and the tilt angle of the output waveguides in the silicon photonic chip is the same as the tilt angle of the end face in the fiber array.
6. The coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences according to claim 5, characterized in that, The tilt angle of the output waveguide in the silicon photonic chip and the tilt angle of the end face in the fiber array are both 8°.
7. The coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences according to claim 1, characterized in that, S40 specifically refers to: A collimating lens is coupled and fixed between the laser chip and the optical isolator in the first channel. The collimating lens is fixed when the photocurrent value of the MPD coupled to the input waveguide of the first channel in the silicon photonic chip is the maximum. A collimating lens is coupled and fixed between the laser chip and the optical isolator in the second path. The collimating lens is fixed when the photocurrent value of the MPD coupled to the input waveguide of the second channel in the silicon photonic chip is at its maximum.
8. The coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences according to claim 1, characterized in that, The laser chips for the first and second channels are fixed on a ceramic heat sink, the optical isolator is a dual optical isolator, and the output wavelength of each channel of the fiber array is 100G.
9. A coupling method for an 800G DR8 silicon photonic engine with small channel optical power differences according to any one of claims 1 to 8, characterized in that, The S60 specifically refers to: Assuming G4 is the largest, if G1 < G2 < G3 < G4, then under this condition, first couple the converging lens of the first path, then defocus couple the converging lens of the second path, and let the difference between G4 and G1 be 0 to 0.5 dB. If G1 < G3 < G2 < G4, then under this condition, first couple and fix the first path converging lens, then defocus and couple and fix the second path converging lens, and make the difference between G4 and G1 0 to 0.5 dB. If G3 < G1 < G2 < G4, then under this condition, first couple and fix the second path converging lens, then defocus and couple and fix the first path converging lens, and make the difference between G4 and G3 0 to 0.5 dB.
10. An 800G DR8 silicon photonic engine with small channel optical power differences, characterized in that, The coupling method described in any one of claims 1 to 9 is used to obtain the coupling.