800G DR8 silicon optical engine
By adjusting the distribution mode of the input waveguide in the 800G DR8 silicon optical engine and coupling with the roof prism, the problems of optical power consistency and coupling efficiency in traditional designs are solved, and performance improvements under high temperature conditions are achieved.
Patent Information
- Application Number
- CN202510470557.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-15
- Publication Date
- 2025-06-10
AI Technical Summary
The traditional 800G DR8 silicon optical engine has problems with optical power consistency and coupling efficiency in structural design, especially under high temperature conditions, which leads to an expansion of optical power differences.
An 800G DR8 silicon light engine is designed. By adjusting the first input waveguide and the second input waveguide of the DR8 silicon light chip into a symmetrical distribution of eight characters and coupled with the roof prism with eight characters and symmetrical distribution of eight characters, we ensure that the thickness of the two converging lenses is the same, so that the focal length and spherical aberration of the two converging lenses are the same, avoiding affecting the layout space and coupling efficiency of the PCB board.
Through this design, the consistency and coupling efficiency of optical power under high temperature conditions are achieved, avoiding the expansion of optical power differences and improving overall performance.
Smart Images
Figure CN120122288A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of optical engines, and particularly to an 800G DR8 silicon optical engine. Background Art
[0002] The structure of a traditional 800G DR8 silicon optical engine is specifically as Figure 1 shown. It includes: a DR8 silicon optical chip, two laser chips, two collimating lenses, a dual optical isolator, a prism, and a multi-channel fiber array. The DR8 silicon optical chip has two input waveguides and eight output waveguides. The two input waveguides are both inclined and parallel to each other. The eight output waveguides are both inclined and parallel to each other. The inclination angle is usually 8°±0.1°. Each of the two input waveguides is coupled to the input of a first 1×2 optical splitter. The two outputs of each first 1×2 optical splitter are respectively coupled to the inputs of two second 1×2 optical splitters. The eight outputs of the four second 1×2 optical splitters are each coupled to one of the eight output waveguides through an MZM modulator;
[0003] The prism is coupled to the two input waveguides of the DR8 silicon optical chip. A dual optical isolator is horizontally arranged on the light incident side of the prism. The dual optical isolator is coupled to the light incident surface of the roof prism through two horizontally distributed converging lenses. The two converging lenses are not arranged side by side, that is, one of the two converging lenses is closer to the dual optical isolator, and the other converging lens is farther from the dual optical isolator. Two horizontally distributed laser chips are arranged on the light incident side of the dual optical isolator. A horizontally distributed collimating lens is coupled between each laser chip and the dual optical isolator. The eight output waveguides of the DR8 silicon optical chip are coupled to the multi-channel fiber array. To expand the mode spot for easy coupling, the two input waveguides of the DR8 silicon optical chip are coupled to the same prism. The prism has an inclined light incident surface. Two horizontal lights are incident on the same light incident surface of the prism. The prism can turn the two horizontal lights through one light incident surface and couple the two lights into the two input waveguides of the DR8 silicon optical chip respectively, that is, refract the 0-degree light into 8°±0.1°, which is the same as the inclination angle of the two input waveguides. Since the two horizontal lights are incident on the same light incident surface of the prism, the distances from the two light incident points of the prism to the two input waveguides are different, that is, the thicknesses at two places of the roof prism are different. Assuming that the converging lens closer to the dual optical isolator is B and the other converging lens is A, it will lengthen the focal length of lens B, resulting in a longer focal length of lens B, affecting the layout space of the PCB board. In addition, the thickness of the area of the prism corresponding to lens B is thicker, resulting in a larger spherical aberration of lens B, a lower coupling efficiency, and a worse optical power consistency. At high temperatures, the thermal expansion of the area of the prism corresponding to lens B is greater, and its high-temperature optical power drops more, further expanding the optical power difference. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide an 800G DR8 silicon optical engine to overcome the deficiencies in the above-mentioned prior art.
[0005] The technical solution of the present invention to solve the above technical problem is as follows:
[0006] A DR8 800G silicon optical engine includes: a DR8 silicon optical chip and a roof prism edge-coupled to the DR8 silicon optical chip. The DR8 silicon optical chip has a first input waveguide and a second input waveguide symmetrically distributed in an eight-character shape on the same side with the beam port ends facing inwards. The light incident side of the roof prism has a first light incident surface and a second light incident surface symmetrically distributed in an eight-character shape. The light output side of the roof prism is a plane. The first light incident surface of the roof prism is used to turn the horizontal light incident on it by an angle so that the light is coupled into the first input waveguide, and the second light incident surface of the roof prism is used to turn the horizontal light incident on it by an angle so that the light is coupled into the second input waveguide.
[0007] On the basis of the above technical solution, the present invention can also be improved as follows.
[0008] Further, the first input waveguide is negatively inclined at 8° ± 0.1°, and the second input waveguide is positively inclined at 8° ± 0.1°.
[0009] Further, the first light incident surface of the roof prism is used to turn the horizontal light incident on it by 8° ± 0.1° so that the light is coupled into the first input waveguide; the second light incident surface of the roof prism is used to turn the horizontal light incident on it by 8° ± 0.1° so that the light is coupled into the second input waveguide.
[0010] Further, a dual optical isolator is horizontally arranged on the light incident side of the roof prism. The dual optical isolator is coupled to the first light incident surface of the roof prism through a horizontally distributed converging lens, and the dual optical isolator is coupled to the second light incident surface of the roof prism through a horizontally distributed converging lens. The distances of the two converging lenses from the dual optical isolator are the same. Two horizontally distributed laser chips are arranged on the light incident side of the dual optical isolator, and a horizontally distributed collimating lens is coupled between each laser chip and the dual optical isolator.
[0011] Further, the DR8 silicon optical chip has eight output waveguides on the same side. The light output from the first input waveguide is divided into four paths in a geometric progression and is respectively coupled to four of the eight output waveguides, and the light output from the second input waveguide is divided into four paths in a geometric progression and is respectively coupled to the other four output waveguides.
[0012] Further, the first input waveguide and the second input waveguide are each coupled to the input of a first 1×2 optical splitter. The two outputs of each first 1×2 optical splitter are respectively coupled to the inputs of two second 1×2 optical splitters. Each of the eight outputs of the four second 1×2 optical splitters is coupled to one of the eight output waveguides through an MZM modulator.
[0013] Further, the eight output waveguides are all inclined and parallel to each other.
[0014] Further, the inclination angle of the output waveguide is 8° ± 0.1°.
[0015] Further, the first input waveguide, the second input waveguide, and the output waveguide are on the same side.
[0016] Further, the eight output waveguides of the DR8 silicon photonics chip are coupled to a multi-channel fiber array.
[0017] The beneficial effects of the present invention are as follows: The first input waveguide and the second input waveguide of the DR8 silicon photonics chip are adjusted from a parallel inclined distribution to a symmetric figure-eight distribution with the beam inlet ends facing inwards. Then, a roof prism with a first light incident surface and a second light incident surface and with the first light incident surface and the second light incident surface distributed symmetrically in a figure-eight shape is designed, and the DR8 silicon photonics chip is coupled with the roof prism. When two horizontal lights are respectively incident on the first light incident surface and the second light incident surface of the DR8 silicon photonics chip, the distance between the first input waveguide and one light incident point of the roof prism is the same as the distance between the second input waveguide and the other light incident point of the roof prism, that is, the thicknesses at the two places of the roof prism are the same, so that the focal lengths of the two converging lenses are the same, without affecting the PCB board layout space, the spherical aberrations of the two converging lenses are the same, the coupling efficiency is not affected, and there is no difference in optical power at high temperatures. Description of the Drawings
[0018] Figure 1 is a structural diagram of a DR8 800G silicon photonics engine in the prior art;
[0019] Figure 2 is a structural diagram of the DR8 silicon photonics chip in the present invention;
[0020] Figure 3 is a structural diagram of the DR8 800G silicon photonics engine in the present invention.
[0021] In the drawings, the list of components represented by each reference numeral is as follows:
[0022] 1. DR8 silicon photonics chip, 110. First input waveguide, 120. Second input waveguide, 130. Output waveguide, 140. First 1×2 optical splitter, 150. Second 1×2 optical splitter, 160. MZM modulator, 2. Roof prism, 210. First light incident surface, 220. Second light incident surface, 3. Dual optical isolator, 4. Converging lens, 5. Laser chip, 6. Collimating lens, 7. Multi-channel fiber array. Detailed implementation manners
[0023] The principles and features of the present invention will be described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not intended to limit the scope of the present invention.
[0024] Example 1
[0025] As Figure 2 、 Figure 3 shown, a DR8 800G silicon photonics engine includes: a DR8 silicon photonics chip 1 and a roof prism 2. The DR8 silicon photonics chip 1 has a first input waveguide 110 and a second input waveguide 120 on the same side. The first input waveguide 110 and the second input waveguide 120 are symmetrically distributed in a figure-eight shape with the tapered ends facing inward, that is, the first input waveguide 110 and the second input waveguide 120 have the same inclination angle but only different directions.
[0026] The light incident side of the roof prism 2 has a first light incident surface 210 and a second light incident surface 220. The first light incident surface 210 and the second light incident surface 220 are symmetrically distributed in a figure-eight shape, that is, the first light incident surface 210 and the second light incident surface 220 have the same inclination angle but only different directions. The light output side of the roof prism 2 is a plane. The roof prism 2 is edge-coupled with the DR8 silicon photonics chip 1. The first light incident surface 210 of the roof prism 2 is used to turn the horizontal light incident on it (the first light incident surface 210) by an angle so that the light is coupled into the first input waveguide 110. The second light incident surface 220 of the roof prism 2 is used to turn the horizontal light incident on it (the second light incident surface 220) by an angle so that the light is coupled into the second input waveguide 120. That is, after two horizontal light beams are incident on the first light incident surface 210 and the second light incident surface 220 of the roof prism 2, the propagation directions of the two horizontal light beams will change from horizontal parallel to symmetrically distributed in a figure-eight shape.
[0027] Example 2
[0028] As Figure 2 、 Figure 3 shown, this example is a further improvement on the basis of Example 1, specifically as follows:
[0029] The first input waveguide 110 is negatively inclined at 8° ± 0.1°, and the second input waveguide 120 is positively inclined at 8° ± 0.1°. The inclined distribution of the first input waveguide 110 and the second input waveguide 120 can solve the optical reflection problem.
[0030] Embodiment 3
[0031] As Figure 2 、 Figure 3 shown, this embodiment is a further improvement based on Embodiment 2, and the specific details are as follows:
[0032] The first light incident surface 210 of the roof prism 2 is used to turn the incident horizontal light by 8° ± 0.1° so that the light is coupled into the first input waveguide 110, that is, the light is refracted from horizontal to be collinear with the first input waveguide 110; the second light incident surface 220 of the roof prism 2 is used to turn the incident horizontal light by 8° ± 0.1° so that the light is coupled into the second input waveguide 120, that is, the light is refracted from horizontal to be collinear with the second input waveguide 120.
[0033] Taking the first input waveguide 110 negatively inclined at 8° ± 0.1° as an example, the first light incident surface 210 turns the horizontal light negatively by 8° ± 0.1°. Taking the second input waveguide 120 positively inclined at 8° ± 0.1° as an example, the second light incident surface 220 turns the horizontal light positively by 8° ± 0.1°.
[0034] The inclination angles of the first light incident surface 210 and the second light incident surface 220 are determined according to: the material of the roof prism 2, the material of the first input waveguide 110, the material of the second input waveguide 120, and the angle by which the roof prism 2 turns the horizontal light. The specific calculation method of the inclination angle is as follows: Sin(a) × refractive index of air = sin(b) × refractive index of the prism, where b is the inclination angle of the first light incident surface 210 or the second light incident surface 220. Taking the above as an example, that is, b = 8° ± 0.1°. Finally, the inclination angle a of the first light incident surface 210 or the second light incident surface 220 can be determined. For example, if the material of the roof prism 2, the material of the first input waveguide 110, and the material of the second input waveguide 120 are silica, and based on the refractive index of silica, the inclination angle a can be determined. This is only an exemplary expression and is not limited to this material.
[0035] Embodiment 4
[0036] As Figure 2 、 Figure 3 shown, this embodiment is a further improvement based on any one of Embodiments 1 to 3, and the specific details are as follows:
[0037] A dual optical isolator 3 is horizontally arranged on the light incident side of the roof prism 2. The dual optical isolator 3 is coupled to the first light incident surface 210 of the roof prism 2 through a horizontally distributed converging lens 4, and the dual optical isolator 3 is coupled to the second light incident surface 220 of the roof prism 2 through a horizontally distributed converging lens 4. That is, there are two converging lenses 4, and the distances of the two converging lenses 4 from the dual optical isolator 3 are the same. Two horizontally distributed laser chips 5 are arranged on the light incident side of the dual optical isolator 3. A horizontally distributed collimating lens 6 is coupled between each laser chip 5 and the dual optical isolator 3. That is, there are two collimating lenses 6. The emitted light of one of the two laser chips 5 is incident on the first light incident surface 210 of the roof prism 2 after passing through the collimating lens 6, the dual optical isolator 3, and the converging lens 4 in sequence. The emitted light of the other laser chip 5 among the two laser chips 5 is incident on the second light incident surface 220 of the roof prism 2 after passing through the collimating lens 6, the dual optical isolator 3, and the converging lens 4 in sequence. The laser chips 5 are horizontally distributed, that is, distributed at 0 degrees, which is convenient for chip mounting and can also improve the optical power and yield of the 800G silicon optical engine. The collimating lenses 6 and the converging lenses 4 are horizontally distributed, that is, distributed at 0 degrees, which is convenient for coupling.
[0038] Embodiment 5
[0039] As Figure 2 、 Figure 3 shown, this embodiment is a further improvement based on any one of Embodiments 1 to 4, and the specific content is as follows:
[0040] The DR8 silicon optical chip 1 has eight output waveguides 130 on the same side. The light output from the first input waveguide 110 is divided into four equal parts in a geometric ratio and is respectively coupled to four of the eight output waveguides 130. The light output from the second input waveguide 120 is divided into four equal parts in a geometric ratio and is respectively coupled to the other four of the eight output waveguides 130.
[0041] The specific implementation method is as follows: The first input waveguide 110 is coupled to the input of a first 1×2 optical splitter 140, and the second input waveguide 120 is coupled to the input of a first 1×2 optical splitter 140. That is, there are two first 1×2 optical splitters 140. The two outputs of each first 1×2 optical splitter 140 are respectively coupled to the inputs of two second 1×2 optical splitters 150. That is, there are four second 1×2 optical splitters 150. The first 1×2 optical splitter 140 and the second 1×2 optical splitter 150 both split light in equal proportion. The eight outputs of the four second 1×2 optical splitters 150 are each coupled to one of the eight output waveguides 130 through an MZM modulator 160. Taking the first input waveguide 110 as an example, when the emitted light is coupled into the first input waveguide 110, the emitted light enters the first 1×2 optical splitter 140, and the first 1×2 optical splitter 140 splits the emitted light into two beams with a splitting ratio of 50:50 and propagates them respectively to the two second 1×2 optical splitters 150. Each second 1×2 optical splitter 150 further splits the light accounting for 50% of the emitted light into two beams with a splitting ratio of 50:50, and finally each propagates through an MZM modulator 160 into the two output waveguides 130 to which they are coupled respectively.
[0042] The eight output waveguides 130 are all inclined and parallel to each other. The inclined distribution of the output waveguides 130 can solve the problem of light reflection. The output waveguides 130 are preferably inclined forward by 8°±0.1°. The first input waveguide 110, the second input waveguide 120, and the output waveguides 130 are on the same side.
[0043] The eight output waveguides 130 of the DR8 silicon photonics chip 1 are coupled to the multi-channel fiber array 7, and the number of channels of the multi-channel fiber array 7 is at least eight.
[0044] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.
Claims
1. A DR8 800G silicon photonic engine, characterized in that: include: A DR8 silicon photonic chip (1) and a roof prism (2) coupled to the edge of the DR8 silicon photonic chip (1); the DR8 silicon photonic chip (1) has a first input waveguide (110) and a second input waveguide (120) on the same side, which are symmetrically distributed in an eight-shaped pattern and have their beam ends facing inward; the light-incident side of the roof prism (2) has a first light-incident surface (210) and a second light-incident surface (220) which are symmetrically distributed in an eight-shaped pattern; the light-emitting side of the roof prism (2) is a plane; the first light-incident surface (210) of the roof prism (2) is used to turn the angle of horizontal light incident thereon so that the light is coupled into the first input waveguide (110); the second light-incident surface (220) of the roof prism (2) is used to turn the angle of horizontal light incident thereon so that the light is coupled into the second input waveguide (120).
2. The DR8 800G silicon photonic engine according to claim 1, characterized in that: The first input waveguide (110) is negatively inclined at 8°±0.1°, and the second input waveguide (120) is positively inclined at 8°±0.1°.
3. The DR8 800G silicon photonic engine according to claim 2, characterized in that: The first light incident surface (210) of the roof prism (2) is used to bend the horizontal light incident thereon by 8°±0.1° so as to couple the light into the first input waveguide (110); and the second light incident surface (220) of the roof prism (2) is used to bend the horizontal light incident thereon by 8°±0.1° so as to couple the light into the second input waveguide (120).
4. A DR8 800G silicon photonic engine according to any one of claims 1 to 3, characterized in that: A double optical isolator (3) is horizontally arranged on the light incident side of the roof prism (2); the double optical isolator (3) is coupled to a first light incident surface (210) of the roof prism (2) via a horizontally distributed converging lens (4); the double optical isolator (3) is coupled to a second light incident surface (220) of the roof prism (2) via a horizontally distributed converging lens (4); the two converging lenses (4) are at the same distance from the double optical isolator (3); two horizontally distributed laser chips (5) are arranged on the light incident side of the double optical isolator (3); and a horizontally distributed collimating lens (6) is coupled between each laser chip (5) and the double optical isolator (3).
5. A DR8 800G silicon photonic engine according to any one of claims 1 to 4, characterized in that: The DR8 silicon photonic chip (1) has eight output waveguides (130) on the same side, the light output from the first input waveguide (110) is divided into four paths in equal proportion and respectively coupled with four of the eight output waveguides (130), and the light output from the second input waveguide (120) is divided into four paths in equal proportion and respectively coupled with the other four output waveguides (130).
6. The DR8 800G silicon photonic engine according to claim 5, characterized in that: The first input waveguide (110) and the second input waveguide (120) are each coupled to the input of a first 1×2 optical splitter (140), the two outputs of each first 1×2 optical splitter (140) are respectively coupled to the inputs of two second 1×2 optical splitters (150), and the eight outputs of the four second 1×2 optical splitters (150) are each coupled one by one to the eight output waveguides (130) via an MZM modulator (160).
7. The DR8 800G silicon photonic engine according to claim 5, characterized in that: The eight output waveguides (130) are all tilted and parallel to each other.
8. The DR8 800G silicon photonic engine according to claim 7, characterized in that: The output waveguide (130) has an inclination angle of 8°±0.1°.
9. The DR8 800G silicon photonic engine according to claim 5, characterized in that: The first input waveguide (110), the second input waveguide (120) and the output waveguide (130) are located on the same side.
10. The DR8 800G silicon photonic engine according to claim 5, characterized in that: The eight output waveguides (130) of the DR8 silicon photonic chip (1) are coupled to a multi-channel optical fiber array (7).