DR4 silicon optical chip convenient for patch coupling and 400G optical module
By designing a reversible optical path structure for the input waveguide and test waveguide on the DR4 silicon photonic chip and using a small-sized fiber array for testing, the problems of low testing efficiency and inconvenient patching in the prior art are solved, realizing efficient optical chip testing and convenient patch coupling.
Patent Information
- Application Number
- CN202520714379.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-15
- Publication Date
- 2026-03-03
- Estimated Expiration
- 2035-04-15
AI Technical Summary
The existing DR4 silicon photonics chip requires coupling two fiber arrays during testing, resulting in low testing efficiency. Furthermore, when applied to 400G optical modules, patching and coupling are inconvenient.
Design a DR4 silicon photonics chip with one input waveguide, one test waveguide, and four output waveguides on the same side. The input waveguides are distributed at 0 degrees, while the test and output waveguides are tilted and parallel. The optical path is reversible through a 2×2 coupler. A small-sized test fiber array is used to couple with the test and output waveguides. The reversible test optical path is used to test the insertion loss of the input waveguide, and the light is distributed equally to the four output waveguides.
It achieves efficient optical chip testing, reduces coupling angle error requirements, facilitates chip mounting and coupling, and allows laser chips and lenses to be mounted and coupled at 0 degrees, improving testing efficiency and convenience.
Smart Images
Figure CN223966719U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of optical module technology, specifically to a DR4 silicon photonics chip and a 400G optical module that are easy to surface mount and couple. Background Technology
[0002] The DR4 silicon photonics chips used in traditional 400G optical modules are divided into two categories, as follows:
[0003] 1) The DR4 silicon photonics chip has one input waveguide and four output waveguides on the same side. The input waveguides are distributed at 0 degrees, and the four output waveguides are tilted and parallel to each other. The tilted distribution of the output waveguides can solve the light reflection problem. Typically, the tilt angle of the output waveguides is 8°±0.1°. The input waveguide is coupled to the input of a first 1×2 coupler. The two outputs of the first 1×2 coupler are each coupled to the input of a second 1×2 coupler. Each output of each second 1×2 coupler is coupled to an output waveguide via an MZM modulator. The first and second 1×2 couplers split the light proportionally. When testing this type of DR4 silicon photonics chip, it is required to couple two fiber arrays, i.e., one optical... One fiber array is coupled to the input waveguide of the DR4 silicon photonics chip, and another fiber array is coupled to the four output waveguides of the DR4 silicon photonics chip. The polarization-maintaining fiber in the fiber array coupled to the input waveguide of the DR4 silicon photonics chip is connected to an external test light source, while the polarization-maintaining fibers in the fiber arrays coupled to the four output waveguides of the DR4 silicon photonics chip are each connected to an external optical power meter. Because two fiber arrays need to be coupled during testing, the testing efficiency is low. However, the advantage of this type of DR4 silicon photonics chip is that the input waveguide is distributed at 0 degrees (due to the optical isolator in the optical transmitter, the input waveguide can be distributed at 0 degrees), allowing the laser chip to be mounted at 0 degrees and the lens to be coupled at 0 degrees when coupled to the optical transmitter, making mounting and coupling more convenient. Figure 1 For 400G optical modules with this type of DR4 silicon photonics chip, Figure 2 This is a test image of this type of DR4 silicon photonics chip;
[0004] 2) The DR4 silicon photonics chip has one input waveguide and four output waveguides on the same side. The input waveguide and the four output waveguides are tilted and parallel to each other. This tilted distribution helps solve the light reflection problem. Typically, the tilt angle of the input and output waveguides is 8° ± 0.1°. The input waveguide is coupled to the input of a first 1×2 coupler. Each of the two outputs of the first 1×2 coupler is coupled to the input of a second 1×2 coupler. Each output of each second 1×2 coupler is coupled to an output waveguide via an MZM modulator. The first and second 1×2 couplers split the light proportionally. During testing, this type of DR4 silicon photonics chip exhibits light reflection due to the tilted input and four output waveguides. Because the fibers are obliquely distributed and parallel to each other, only one large-size fiber array needs to be coupled. This large-size fiber array is coupled to both the input waveguide and the four output waveguides of the DR4 silicon photonics chip. The polarization-maintaining fibers coupled to the input waveguide of the DR4 chip are connected to an external test light source, while the polarization-maintaining fibers coupled to the four output waveguides are connected to external optical power meters. The advantage of this type of DR4 chip is that only one large-size fiber array needs to be coupled, making chip testing convenient. The disadvantage is that due to the oblique distribution of the input waveguide, the laser chip must be tilted at the same angle for mounting when coupled to the optical transmitter, which places high demands on the mounting process. Simultaneously, the lenses must also be rotated and tilted at the same angle for coupling, making coupling inconvenient. Figure 3 For 400G optical modules with this type of DR4 silicon photonics chip, Figure 4 This is a test image of this type of DR4 silicon photonics chip. Utility Model Content
[0005] The technical problem to be solved by this utility model is to provide a DR4 silicon photonics chip and a 400G optical module that are easy to be surface-mounted and coupled, so as to overcome the shortcomings of the prior art.
[0006] The technical solution of this utility model to solve the above-mentioned technical problems is as follows:
[0007] A DR4 silicon photonics chip has an input waveguide, a test waveguide, and four output waveguides arranged sequentially on the same side. The input waveguides are arranged at 0 degrees, while the test and output waveguides are inclined and parallel to each other. The input and test waveguides are coupled and their optical paths are reversible. The input and test waveguides are each coupled to two inputs of a 2×2 coupler. One output of the 2×2 coupler is split into two paths in a proportional manner and coupled to two of the four output waveguides respectively. The other output is also split into two paths in a proportional manner and coupled to the other two output waveguides respectively.
[0008] The beneficial effects of this invention are as follows: When testing the DR4 silicon photonics chip, the testing method is as follows: a test fiber array with at least five channels is coupled to the test waveguide and four output waveguides of the DR4 silicon photonics chip. A test light source is externally connected to the polarization-maintaining fiber coupled to the test waveguide in the test fiber array. An optical power meter is externally connected to the four polarization-maintaining fibers coupled to the four output waveguides in the test fiber array. A fixed large-area photodiode (PD) is arranged on the input side of the DR4 silicon photonics chip, and the PD is coupled to the input waveguide of the DR4 silicon photonics chip. Once the test light source and optical power meter are turned on, the DR4 silicon photonics chip can be tested. The test light is coupled into the input waveguide of the DR4 silicon photonics chip. Then, part of the light is split into the input waveguide and coupled into the PD, so that the insertion loss of the input waveguide can be tested. The other light is split into four equal paths, and the four equal paths are coupled into the four output waveguides respectively. Then, the four output waveguides are coupled into the polarization-maintaining fibers of the four external optical power meters respectively. Finally, the optical power meter measures the optical power value of each path to complete the test of the DR4 silicon photonics chip.
[0009] When testing the DR4 silicon photonics chip, only a small-sized test fiber array needs to be coupled. Compared with a large-sized fiber array, the closer channel spacing makes coupling easier and the requirements for coupling angle error are lower. Furthermore, since the optical path between the input waveguide and the test waveguide is reversible, the insertion loss of the input waveguide can be tested. The input waveguide of the DR4 silicon photonics chip is distributed at 0 degrees. Therefore, when the DR4 silicon photonics chip is applied to a 400G optical module, the laser chip can be mounted at 0 degrees and the lens can be coupled at 0 degrees, which is more convenient for subsequent patch laser chips and coupling lenses.
[0010] Based on the above technical solution, the present invention can be further improved as follows.
[0011] Furthermore, the tilt angle of the test waveguide and the output waveguide is 8°±0.1°.
[0012] The further beneficial effect of adopting the above is that the tilted distribution can solve the problem of light reflection.
[0013] Furthermore, the test waveguide and the four output waveguides were evenly spaced.
[0014] The further beneficial effect of adopting the above is that it facilitates the use of a standard fiber array to couple with the test waveguide and the four output waveguides respectively for testing.
[0015] Furthermore, when light is coupled into the input waveguide, 1% to 3% of the light is directed to the test waveguide, while the remaining 97% to 99% of the light is directed equally to one input of the optical device.
[0016] Furthermore, when light is coupled into the waveguide, 88% to 92% of the light is directed to the input waveguide, while the remaining 8% to 12% is directed to the other input of the optical device.
[0017] Furthermore, each of the two outputs of the 2×2 coupler is coupled to the input of a 1×2 coupler, and each output of the 1×2 coupler is coupled to an output waveguide via an MZM modulator.
[0018] Based on the above technical solution, this utility model also provides a 400G optical module, including the above-mentioned DR4 silicon photonics chip.
[0019] The further beneficial effects of adopting the above are as follows: the input waveguide of the DR4 silicon photonics chip is distributed at 0 degrees, which makes it more convenient for subsequent surface-mount laser chips and coupling lenses to be surface-mounted at 0 degrees and coupled at 0 degrees.
[0020] Furthermore, the input waveguide of the DR4 silicon photonics chip is coupled to the optical transmitter.
[0021] Furthermore, the optical emitting end includes: a laser chip, a collimating lens, an optical isolator, and a converging lens, which are sequentially coupled along the direction of light propagation, with the laser chip fixed on a ceramic heat sink.
[0022] Furthermore, the four output waveguides of the DR4 silicon photonics chip are coupled to a multi-channel fiber array. Attached Figure Description
[0023] Figure 1 This is a structural diagram of a 400G optical module with a first-type DR4 silicon photonic chip in the prior art;
[0024] Figure 2 This is a test diagram of the edge coupling of the first type of DR4 silicon photonic chip in the prior art;
[0025] Figure 3 This is a structural diagram of a 400G optical module with a second-type DR4 silicon photonic chip in the prior art;
[0026] Figure 4 This is a test diagram of the edge coupling of a second type of DR4 silicon photonic chip in the prior art;
[0027] Figure 5 This is a structural diagram of the DR4 silicon photonics chip in this utility model;
[0028] Figure 6 This is a test diagram of the edge coupling of the DR4 silicon photonics chip in this invention;
[0029] Figure 7 This is a structural diagram of the 400G optical module in this utility model.
[0030] The attached diagram lists the components represented by each number as follows:
[0031] 1. DR4 silicon photonics chip; 110. Input waveguide; 120. Test waveguide; 130. Output waveguide; 140. 2×2 coupler; 150. 1×2 coupler; 160. MZM modulator; 2. Optical transmitter; 210. Laser chip; 220. Collimating lens; 230. Optical isolator; 240. Converging lens; 250. Ceramic heat sink; 3. Multi-channel fiber array; 4. Test light source; 5. Optical power meter; 6. PD; 7. Test fiber array. Detailed Implementation
[0032] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.
[0033] Example 1
[0034] like Figure 5 As shown, a DR4 silicon photonics chip that is easy to be coupled to the surface has an input waveguide 110, a test waveguide 120 and four output waveguides 130 arranged sequentially on the same side. That is, the test waveguide 120 is located between the input waveguide 110 and the output waveguides 130. The input waveguide 110 is arranged at 0 degrees, while the test waveguide 120 is arranged at an angle and the output waveguides 130 are arranged at an angle. The test waveguide 120 and the output waveguide 130 are parallel to each other.
[0035] The input waveguide 110 is coupled to the test waveguide 120 and the optical path is reversible. That is, when light is coupled into the input waveguide 110, the input waveguide 110 can split the light to the test waveguide 120, and when light is coupled into the test waveguide 120, the test waveguide 120 can split the light to the input waveguide 110. The input waveguide 110 and the test waveguide 120 are coupled to the two inputs of a 2×2 coupler 140, respectively. The light output of one of the two outputs of the 2×2 coupler 140 is split into two paths in a proportional manner and coupled to two of the four output waveguides 130, respectively. The light output of the other output of the 2×2 coupler 140 is split into two paths in a proportional manner and coupled to the other two output waveguides 130, respectively.
[0036] When testing this DR4 silicon photonics chip, such as Figure 7 As shown, the testing method is as follows:
[0037] A test fiber array 7 with at least five channels is coupled to the test waveguide 120 and four output waveguides 130 of the DR4 silicon photonics chip 1. A test light source 4 is externally connected to the polarization-maintaining fiber coupled to the test waveguide 120 in the test fiber array 7. An optical power meter 5 is externally connected to the four polarization-maintaining fibers coupled to the four output waveguides 130 in the test fiber array 7. A fixed large-area PD6 is arranged on the input side of the DR4 silicon photonics chip 1, and the PD6 is coupled to the input waveguide 110 of the DR4 silicon photonics chip 1. Turning on the test light source 4 and the optical power meter 5 respectively will activate the test light source. The test begins with the DR4 silicon photonics chip 1. Test light is coupled into the input waveguide 110 of the DR4 silicon photonics chip 1. Then, a portion of the light is split into the input waveguide 110 and coupled into the PD6 (optical chip) to test the insertion loss of the input waveguide 110. The remaining light is split into four equal paths, and each of the four equal paths is coupled into one of the four output waveguides 130. The four output waveguides 130 are then coupled into the polarization-maintaining fibers of four external optical power meters 5. Finally, the optical power meters measure the power value of each path to complete the test of the DR4 silicon photonics chip 1.
[0038] When testing the DR4 silicon photonics chip, only a small-sized test fiber array 7 needs to be coupled. Compared with a large-sized fiber array, the closer channel spacing makes coupling easier and the requirements for coupling angle error are lower. Furthermore, since the optical path between the input waveguide 110 and the test waveguide 120 is reversible, the insertion loss of the input waveguide 110 can be tested. The input waveguide 110 of the DR4 silicon photonics chip 1 is distributed at 0 degrees. Therefore, when the DR4 silicon photonics chip is applied to a 400G optical module, for subsequent surface-mount laser chips and coupling lenses, the laser chip 210 can be surface-mounted at 0 degrees and the lens can be coupled at 0 degrees, which is more convenient for surface-mounting and coupling.
[0039] Example 2
[0040] like Figure 5 As shown, this embodiment is a further improvement on embodiment 1, as detailed below:
[0041] The tilt angle of waveguide 120 is 8°±0.1°, and the tilt angle of output waveguide 130 is 8°±0.1°. The tilt distribution can solve the problem of light reflection.
[0042] Furthermore, the test waveguide 120 and the four output waveguides 130 are equally spaced, which facilitates the use of a standard fiber optic array to couple with the test waveguide 120 and the four output waveguides 130 respectively for testing.
[0043] Example 3
[0044] like Figure 5As shown, this embodiment is a further improvement on embodiment 1 or 2, as detailed below:
[0045] When light is coupled into the input waveguide 110, 1% to 3% of the light is directed to the test waveguide 120, and the remaining 97% to 99% of the light is equally directed to one input of the optical fiber device. For example, when light is coupled into the input waveguide 110, 2% of the light is directed to the test waveguide 120, and the remaining 98% of the light is equally directed to one input of the optical fiber device. Of course, this ratio is only an exemplary description, and fluctuations around this value are not excluded in actual applications.
[0046] Furthermore, when light is coupled into waveguide 120, 88% to 92% of the light is directed into waveguide 110, and the remaining 8% to 12% is directed equally into the other input of the optical fiber device. For example, when light is coupled into waveguide 120, 90% of the light is directed into waveguide 110, and the remaining 10% is directed equally into the other input of the optical fiber device. Of course, this ratio is only an exemplary description, and fluctuations around this value are not excluded in actual applications.
[0047] Example 4
[0048] like Figure 5 As shown, this embodiment is a further improvement on embodiment 1, 2, or 3, as detailed below:
[0049] The two outputs of the 2×2 coupler 140 are each coupled to the input of a 1×2 coupler 150, thus having two 1×2 couplers 150. Each output of the 1×2 coupler 150 is coupled to an output waveguide 130 via an MZM modulator 160, thus having four MZM modulators 160. The 2×2 coupler 140 and the 1×2 coupler 150 split the light proportionally, thereby splitting the light coupled into the 2×2 coupler 140 into four paths in a proportional manner and then coupling them into the four output waveguides 130 respectively.
[0050] Example 5
[0051] like Figure 6 As shown, a 400G optical module includes: a DR4 silicon photonic chip 1 as described in any of embodiments 1 to 4.
[0052] Example 6
[0053] like Figure 6 As shown, this embodiment is a further improvement on embodiment 5, as detailed below:
[0054] The input waveguide 110 of the DR4 silicon photonics chip is coupled to the optical transmitter 2, meaning that the light emitted by the optical transmitter 2 can be coupled into the input waveguide 110 of the DR4 silicon photonics chip.
[0055] Furthermore, the optical emitting end includes a laser chip 210, a collimating lens 220, an optical isolator 230, and a converging lens 240, which are coupled sequentially along the light propagation direction. The laser chip 210 is fixed on a ceramic heat sink 250. The light emitted by the laser chip 210 passes sequentially through the laser chip 210, the collimating lens 220, the optical isolator 230, and the converging lens 240 before being coupled into the input waveguide 110 of the DR4 silicon photonics chip.
[0056] The four output waveguides 130 of the DR4 silicon photonic chip 1 are coupled to the multi-channel fiber array 3.
[0057] 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 DR4 silicon photonics chip that is easy to surface mount and couple, characterized in that, It has an input waveguide (110), a test waveguide (120) and four output waveguides (130) arranged sequentially on the same side. The input waveguide (110) is arranged at 0 degrees. The test waveguide (120) and the output waveguides (130) are both inclined and parallel to each other. The input waveguide (110) is coupled to the test waveguide (120) and the optical path is reversible. The input waveguide (110) and the test waveguide (120) are coupled to the two inputs of a 2×2 coupler (140) respectively. The output light of one of the 2×2 couplers (140) is split into two paths in a proportional manner and coupled to two of the four output waveguides (130) respectively. The output light of the other output is split into two paths in a proportional manner and coupled to the other two output waveguides (130) respectively.
2. The DR4 silicon photonics chip according to claim 1, characterized in that, The tilt angle of the test waveguide (120) and the output waveguide (130) is 8°±0.1°.
3. A DR4 silicon photonics chip according to claim 1, characterized in that, The test waveguide (120) and the four output waveguides (130) are equally spaced.
4. A DR4 silicon photonics chip according to claim 1, characterized in that, When light is coupled into the input waveguide (110), 1% to 3% of the light is directed to the test waveguide (120), and the remaining 97% to 99% of the light is directed equally to one input of the optical device.
5. A DR4 silicon photonics chip according to claim 1, characterized in that, When light is coupled into the test waveguide (120), 88% to 92% of the light is directed to the input waveguide (110), and the remaining 8% to 12% of the light is directed to the other input of the optical device.
6. A DR4 silicon photonics chip according to any one of claims 1 to 5, characterized in that, The two outputs of the 2×2 coupler (140) are each coupled to the input of a 1×2 coupler (150), and each output of the 1×2 coupler (150) is coupled to an output waveguide (130) via an MZM modulator (160).
7. A 400G optical module, characterized in that, include: The DR4 silicon photonics chip (1) as described in any one of claims 1 to 6.
8. A 400G optical module according to claim 7, characterized in that, The input waveguide (110) of the DR4 silicon photonic chip is coupled to the optical transmitter (2).
9. A 400G optical module according to claim 8, characterized in that, The light emitting end includes a laser chip (210), a collimating lens (220), an optical isolator (230), and a converging lens (240) coupled sequentially along the light propagation direction. The laser chip (210) is fixed on a ceramic heat sink (250).
10. A 400G optical module according to claim 7, characterized in that, The four output waveguides (130) of the DR4 silicon photonic chip (1) are coupled to the multi-channel fiber array (3).