Low-cost 800G 2XFR4 silicon light engine

Abstract

The invention relates to a low-cost 800G 2XFR4 silicon light engine which comprises four collimating lenses distributed side by side, the light incident side of each collimating lens is coupled with a laser chip, the light emergent sides of the four collimating lenses are jointly coupled with a prism used for reducing the distance between four paths of parallel collimated light, and the light emergent side of each collimating lens is coupled with a laser chip. The light emitting side of the prism is sequentially coupled with an array converging lens, a polarization-independent optical isolator and a silicon optical chip in the light propagation direction, or the light emitting side of the prism is sequentially coupled with a polarization-independent optical isolator, an array converging lens and a silicon optical chip in the light propagation direction. The polarization-independent optical isolator has the advantages that the number of the lenses is reduced, the number of coupling times can be reduced, coupling time consumption can be shortened, only one large polarization-independent optical isolator can be adopted, compared with four independent polarization-independent optical isolators adopted in the prior art, the size of the polarization-independent optical isolator can be integrally reduced, and the size of the polarization-independent optical isolator can be reduced. And the cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of optical engines, and in particular to a low-cost 800G 2XFR4 silicon photonics optical engine. Background Art

[0002] The structure of the traditional 800G 2XFR4 silicon photonic engine is as follows: Figure 1 As shown, it includes: a silicon photonic chip and four parallel distributed laser chips, the silicon photonic chip has four input light waveguides and two output light waveguides, two of the four input light waveguides are coupled with one of the two output light waveguides, and the other two input light waveguides are coupled with the other of the two output light waveguides, the two output light waveguides of the silicon photonic chip are coupled with a dual-channel optical fiber array, and the light beam emitted by each laser chip is coupled into one of the input light waveguides of the silicon photonic chip through a collimating lens, a polarization-independent optical isolator and a converging lens in sequence, that is, it has four collimating lenses, four polarization-independent optical isolators and four converging lenses. In order to improve the coupling tolerance, a double-lens solution is adopted, that is, the collimating lens first collimates the emitted light of the laser chip, and then the converging lens converges the collimated light to the silicon photonic chip In the optical waveguide of the chip, since there are four collimating lenses and four converging lenses in this solution, it needs to be coupled eight times, which is time-consuming. In addition, the dual-channel optical fiber array also needs to be coupled once. Since the minimum size of the collimating lens is generally 0.6mm, a space for overflow glue must be reserved between two adjacent collimating lenses. The gap is usually 0.4mm, so the center distance between the optical axes of the laser chips of two adjacent channels is 1mm. There are four polarization-independent optical isolators, which are relatively expensive, and the chip needs to be mounted four times. Since two adjacent polarization-independent optical isolators have the problem of magnetic force repelling each other, it affects the efficiency of mounting. In addition, considering the overflow glue problem of the collimating lens, polarization-independent optical isolator and converging lens, the three materials must have an appropriate gap in the direction of light propagation, resulting in a relatively large overall space, which causes tight space for PCB board layout. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a low-cost 800G 2XFR4 silicon photonics engine to overcome the deficiencies in the above-mentioned prior art.

[0004] The technical solution of the present invention to solve the above technical problems is as follows: a low-cost 800G 2XFR4 silicon photonics engine, comprising: four collimating lenses distributed side by side, each collimating lens is coupled to a laser chip on the light incident side, and the light output sides of the four collimating lenses are commonly coupled to a prism for reducing the spacing between four parallel collimated lights; the light output side of the prism is sequentially coupled to an array converging lens, a polarization-independent optical isolator and a silicon photonics chip along the light propagation direction, or the light output side of the prism is sequentially coupled to a polarization-independent optical isolator, an array converging lens and a silicon photonics chip along the light propagation direction.

[0005] The beneficial effects of the present invention are:

[0006] The present invention is provided with four collimating lenses and one array converging lens, that is, a total of five lenses. Under the same coupling tolerance requirement, the number of lenses is reduced, thereby reducing the number of coupling times, shortening the coupling time, and improving production efficiency. Since the spacing of the four parallel collimated lights is reduced, only one large polarization-independent optical isolator can be used. Compared with the prior art using four separate polarization-independent optical isolators, the size of the polarization-independent optical isolator can be reduced as a whole, thereby reducing costs. In addition, the number of polarization-independent optical isolators is reduced from four to one, so there is no problem of magnetic repulsion between the fourth patch and the adjacent channels, and the patch efficiency is not affected. In addition, the problem of glue overflow of the polarization-independent optical isolator and the array converging lens does not need to be considered, so that the space occupied by the polarization-independent optical isolator, the collimating lens and the array converging lens as a whole is reduced, effectively alleviating the problem of tight space in the PCB board layout. When the spacing of the four parallel collimated lights is reduced, the spacing of the four parallel converging lights will also be reduced, so the spacing of the four light input waveguides of the silicon photonic chip will also be reduced. Since the spacing of the four light input waveguides of the silicon photonic chip is reduced, the size of the silicon photonic chip can be reduced, thereby reducing costs.

[0007] Based on the above technical solution, the present invention can also be improved as follows.

[0008] Furthermore, the center distance between the optical axes of two adjacent laser chips is 1 mm. The prism is used to reduce the spacing of four parallel collimated lights from 1 mm to 0.4 mm to 0.55 mm. The spacing between the four light input waveguides of the silicon photonic chip is 0.4 mm to 0.55 mm.

[0009] The further beneficial effect of adopting the above method is as follows: since the spacing is reduced to 0.4mm~0.55mm, only one large polarization-independent optical isolator can be used. Compared with the prior art that uses four separate polarization-independent optical isolators, the size of the polarization-independent optical isolator can be reduced as a whole, thereby reducing costs. In addition, the number of polarization-independent optical isolators is reduced from four to one, so there is no problem of magnetic repulsion between four patches and adjacent channels. Since the spacing between the four optical input waveguides of the silicon photonic chip is reduced from 1mm to 0.4mm~0.55mm, the size of the silicon photonic chip can be reduced, thereby reducing costs.

[0010] Going further: the prism is used to reduce the spacing of four parallel collimated lights from 1mm to 0.5mm, and the spacing between the four light input waveguides of the silicon photonic chip is 0.5mm.

[0011] Furthermore, the prism has an incident surface and an exit surface which are parallel to each other, and the prism has a first reflection surface, a second reflection surface, a third reflection surface and a fourth reflection surface in sequence, the first reflection surface and the second reflection surface are parallel to each other, the third reflection surface and the fourth reflection surface are parallel to each other, the second reflection surface and the third reflection surface are distributed in an eight-shaped shape with the beam opening end facing the exit surface, and the four laser chips are a first laser chip, a second laser chip, a third laser chip and a fourth laser chip in sequence;

[0012] The light beam emitted by the first laser chip is incident on the incident surface between the first reflection surface and the second reflection surface through the collimating lens, and is transmitted from the incident surface to the first reflection surface, first turned 90° by the first reflection surface and then reflected to the second reflection surface, and then turned 90° by the second reflection surface and then reflected to the exit surface;

[0013] The light beam emitted by the second laser chip is incident on the incident surface between the second reflection surface and the third reflection surface through the collimating lens, and is transmitted from the incident surface to the exit surface;

[0014] The light beam emitted by the third laser chip is incident on the incident surface between the third reflection surface and the fourth reflection surface through the collimating lens, and is transmitted from the incident surface to the exit surface;

[0015] The light beam emitted by the fourth laser chip is incident on the incident surface between the third reflection surface and the fourth reflection surface through the collimating lens, and is transmitted from the incident surface to the fourth reflection surface, first turned 90° by the fourth reflection surface and then reflected to the third reflection surface, and then turned 90° by the third reflection surface and reflected to the exit surface.

[0016] A further beneficial effect of the above method is that the spacing between the four parallel collimated lights can be effectively reduced from 1 mm to 0.5 mm.

[0017] Furthermore, the light-emitting side of the prism is sequentially coupled with an array convergence lens, a polarization-independent optical isolator and a silicon photonic chip along the light propagation direction, and the polarization-independent optical isolator is fixed on the side of the silicon photonic chip.

[0018] Furthermore, the light-emitting side of the prism is coupled with a polarization-independent optical isolator, an array converging lens and a silicon photonic chip in sequence along the light propagation direction, and the polarization-independent optical isolator is fixed on the side of the light-emitting side of the prism.

[0019] Furthermore, the two light-emitting waveguides of the silicon photonic chip are coupled to a dual-channel optical fiber array.

[0020] Furthermore, each laser chip is fixed on a ceramic heat sink. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a structural diagram of an 800G 2XFR4 silicon photonics engine in the prior art;

[0022] Figure 2 This is a first structural diagram of the low-cost 800G 2XFR4 silicon photonics engine in the present invention;

[0023] Figure 3 This is a second structural diagram of the low-cost 800G 2XFR4 silicon photonics engine of the present invention;

[0024] Figure 4 Schematic diagram of the structure of the prism in the present invention.

[0025] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0026] 1. Collimating lens, 2. Laser chip, 3. Prism, 310. Incident surface, 320. Exit surface, 330. First reflection surface, 340. Second reflection surface, 350. Third reflection surface, 360. Fourth reflection surface, 4. Array converging lens, 5. Polarization-independent optical isolator, 6. Silicon photonic chip, 610. Input light waveguide, 620. Output light waveguide, 7. Dual-channel optical fiber array, 8. Ceramic heat sink. DETAILED DESCRIPTION

[0027] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0028] Example 1

[0029] like Figure 2 , Figure 3As shown, a low-cost 800G 2XFR4 silicon photonics engine includes: four collimating lenses 1 arranged side by side, and each collimating lens 1 is coupled to a laser chip 2 on the light-incoming side, that is, it has four laser chips 2, and the light-outgoing sides of the four collimating lenses 1 are coupled to a prism 3 for reducing the spacing between four parallel collimated lights;

[0030] like Figure 2 As shown, the light-emitting side of the prism 3 is sequentially coupled with an array convergence lens 4, a polarization-independent optical isolator 5, and a silicon photonic chip 6 along the light propagation direction, which can be specifically understood as follows:

[0031] The four parallel collimated lights emitted by the prism 3 are coupled into the same array converging lens 4, which converts the four parallel collimated lights into four parallel converging lights. Then, the four parallel converging lights are respectively coupled into four light input waveguides 610 of the silicon photonic chip 6 through the same polarization-independent optical isolator 5.

[0032] or, as Figure 3 As shown, the light-emitting side of the prism 3 is sequentially coupled with a polarization-independent optical isolator 5, an array converging lens 4, and a silicon photonic chip 6 along the light propagation direction, which can be specifically understood as follows:

[0033] The four parallel collimated lights emitted by the prism 3 are coupled into the same polarization-independent optical isolator 5, and then coupled into the same array converging lens 4 by the polarization-independent optical isolator 5, and the four parallel collimated lights are converted into four parallel converging lights by the array converging lens 4, and finally coupled into four light input waveguides 610 of the silicon photonic chip 6 respectively;

[0034] The present invention is provided with four collimating lenses 1 and one array converging lens 4, that is, a total of five lenses. Under the same coupling tolerance requirement, the number of lenses is reduced, thereby reducing the number of coupling times, shortening the coupling time, and improving production efficiency. Since the spacing between the four parallel collimated lights is reduced, only one large polarization-independent optical isolator 5 can be used. Compared with the prior art using four separate polarization-independent optical isolators, the size of the polarization-independent optical isolator 5 can be reduced as a whole, thereby reducing the cost. In addition, the number of polarization-independent optical isolators 5 is reduced from four to one, so there is no quadratic patch and adjacent channel. The magnetic repulsion problem does not affect the patch efficiency. In addition, there is no need to consider the overflow problem of the polarization-independent optical isolator 5 and the array converging lens 4, so that the space occupied by the polarization-independent optical isolator 5, the collimating lens 1 and the array converging lens 4 as a whole is reduced, and the problem of tight space in the PCB board layout is effectively alleviated. When the spacing between the four parallel collimated lights is reduced, the spacing between the four parallel converging lights will also be reduced, and then the spacing between the four light input waveguides 610 of the silicon photonic chip 6 can also be reduced. Since the spacing between the four light input waveguides 610 of the silicon photonic chip 6 is reduced, the size of the silicon photonic chip 6 can be reduced, thereby reducing the cost.

[0035] Example 2

[0036] like Figure 2 As shown, this embodiment is a further improvement on the basis of embodiment 1, and the details are as follows:

[0037] The optical axis center spacing between two adjacent laser chips 2 is 1mm, and the prism 3 is used to reduce the spacing of the four-way parallel collimated light from 1mm to 0.4mm-0.55mm. Since the spot diameter is generally 0.4mm or more, the spacing of the four-way parallel collimated light after reduction cannot be too small, so it is selected to be 0.4mm-0.55mm. In the present invention, the spacing of the four-way parallel collimated light always satisfies that it is greater than or equal to the spot diameter. If the reduced size is not large, the reduction in the size of the polarization-independent optical isolator 5 is not obvious, and thus the effect of reducing the cost is not obvious. Since the spacing is reduced to 0.4mm-0.55mm Therefore, only one large polarization-independent optical isolator 5 can be used. Compared with the prior art that uses four separate polarization-independent optical isolators, the size of the polarization-independent optical isolator 5 can be reduced as a whole, thereby reducing the cost. In addition, the number of polarization-independent optical isolators 5 is reduced from four to one, so there is no problem of magnetic repulsion between four patches and adjacent channels. The four light input waveguides 610 of the silicon photonic chip 6 have a spacing of 0.4mm to 0.55mm. Since the spacing of the four light input waveguides 610 of the silicon photonic chip 6 is reduced from 1mm to 0.4mm to 0.55mm, the size of the silicon photonic chip 6 can be reduced, thereby reducing the cost.

[0038] Furthermore, the prism 3 is used to reduce the spacing of the four parallel collimated lights from 1 mm to 0.5 mm, that is, the spacing is reduced by 1 time, and the spacing of the four light input waveguides 610 of the silicon photonic chip 6 is 0.5 mm, that is, the spacing is reduced by 1 time.

[0039] like Figure 2 , Figure 3 , Figure 4 As shown, this embodiment is a further improvement on the basis of Embodiment 1 or 2, and the details are as follows:

[0040] The prism 3 has an incident surface 310 and an exit surface 320 which are parallel to each other. The prism 3 has a first reflecting surface 330, a second reflecting surface 340, a third reflecting surface 350 and a fourth reflecting surface 360 ​​in sequence. The first reflecting surface 330 and the second reflecting surface 340 are parallel to each other. The third reflecting surface 350 and the fourth reflecting surface 360 ​​are parallel to each other. The second reflecting surface 340 and the third reflecting surface 350 are distributed in an eight-shaped shape with the beam end facing the exit surface 320.

[0041] The four laser chips 2 are the first laser chip, the second laser chip, the third laser chip and the fourth laser chip, respectively. Figure 2 , Figure 3 The viewing angle shown, from bottom to top, is the first laser chip, the second laser chip, the third laser chip and the fourth laser chip;

[0042] The light beam emitted by the first laser chip is incident on the incident surface 310 between the first reflection surface 330 and the second reflection surface 340 through the collimating lens 1, and is transmitted from the incident surface 310 to the first reflection surface 330, and then firstly turns 90° from the first reflection surface 330 and reflects toward the second reflection surface 340, and then turns 90° from the second reflection surface 340 and reflects toward the exit surface 320, and finally exits through the exit surface 320;

[0043] The light beam emitted by the second laser chip is incident on the incident surface 310 located between the second reflection surface 340 and the third reflection surface 350 through the collimating lens 1, and is transmitted from the incident surface 310 to the exit surface 320, and finally exits through the exit surface 320;

[0044] The light beam emitted by the third laser chip is incident on the incident surface 310 located between the third reflection surface 350 and the fourth reflection surface 360 ​​through the collimating lens 1, and is transmitted from the incident surface 310 to the exit surface 320, and finally exits through the exit surface 320;

[0045] The light beam emitted by the fourth laser chip is incident on the incident surface 310 between the third reflection surface 350 and the fourth reflection surface 360 ​​through the collimating lens 1, and is transmitted from the incident surface 310 to the fourth reflection surface 360, and then firstly turns 90° from the fourth reflection surface 360 ​​and reflects toward the third reflection surface 350, and then turns 90° from the third reflection surface 350 and reflects toward the exit surface 320, and finally exits through the exit surface 320;

[0046] The above description can be understood as follows: the four parallel collimated lights emitted by the first laser chip, the second laser chip, the third laser chip and the fourth laser chip after passing through the four collimating lenses 1 are respectively recorded as the first channel light, the second channel light, the third channel light and the fourth channel light. Figure 2 , Figure 3 The viewing angles shown are, from bottom to top, channel 1, channel 2, channel 3 and channel 4. The light from channel 1 is close to the light from channel 2 after two 90° turns, and is 0.5 mm away from the light from channel 2. The light from channel 4 enters between the light from channel 2 and channel 3 after two 90° turns, and is 0.5 mm away from the light from channel 2 and channel 3.

[0047] In this embodiment, the prism 3 is formed by gluing two parallelogram prisms and a trapezoidal prism, wherein the trapezoidal prism is located between the two parallelogram prisms. According to the viewing angle of the figure, from bottom to top, it can be understood as: a first parallelogram prism, a trapezoidal prism and a second parallelogram prism.

[0048] Example 4

[0049] like Figure 2 As shown, this embodiment is a further improvement on any one of Embodiments 1 to 3, and the details are as follows:

[0050] The light-emitting side of the prism 3 is coupled with an array convergence lens 4 , a polarization-independent optical isolator 5 and a silicon photonic chip 6 in sequence along the light propagation direction. The polarization-independent optical isolator 5 is fixed on the side of the silicon photonic chip 6 .

[0051] Example 5

[0052] like Figure 3 As shown, this embodiment is a further improvement on any one of Embodiments 1 to 3, and the details are as follows:

[0053] The light-emitting side of the prism 3 is coupled with a polarization-independent optical isolator 5 , an array converging lens 4 and a silicon photonic chip 6 in sequence along the light propagation direction. The polarization-independent optical isolator 5 is fixed on the side of the light-emitting side of the prism 3 .

[0054] Example 6

[0055] like Figure 2 , Figure 3 As shown, this embodiment is a further improvement on any one of Embodiments 1 to 5, and the details are as follows:

[0056] The two light-emitting waveguides 620 of the silicon photonic chip 6 are coupled to a dual-channel optical fiber array 7 . In addition, each laser chip 2 is fixed on a ceramic heat sink 8 , that is, four ceramic heat sinks 8 are provided.

[0057] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A low-cost 800G 2XFR4 silicon photonics engine, characterized in that: include: Four collimating lenses (1) are arranged side by side, each collimating lens (1) is coupled to a laser chip (2) on its light-incoming side, and the light-outgoing sides of the four collimating lenses (1) are coupled to a prism (3) for reducing the spacing between four parallel collimated lights; the light-outgoing side of the prism (3) is sequentially coupled to an array convergence lens (4), a polarization-independent optical isolator (5), and a silicon photonic chip (6) along the light propagation direction, or the light-outgoing side of the prism (3) is sequentially coupled to a polarization-independent optical isolator (5), an array convergence lens (4), and a silicon photonic chip (6) along the light propagation direction.

2. A low-cost 800G 2XFR4 silicon photonics engine according to claim 1, characterized in that: The optical axis center spacing between two adjacent laser chips (2) is 1 mm, the prism (3) is used to reduce the spacing of four parallel collimated lights from 1 mm to 0.4 mm to 0.55 mm, and the spacing of four light input waveguides (610) of the silicon photonic chip (6) is 0.4 mm to 0.55 mm.

3. A low-cost 800G 2XFR4 silicon photonics engine according to claim 1 or 2, characterized in that: The prism (3) is used to reduce the spacing of four parallel collimated lights from 1 mm to 0.5 mm, and the spacing of four light input waveguides (610) of the silicon photonic chip (6) is 0.5 mm.

4. A low-cost 800G 2XFR4 silicon photonics engine according to claim 1, 2 or 3, characterized in that: The prism (3) has an incident surface (310) and an exit surface (320) which are parallel to each other. The prism (3) has a first reflection surface (330), a second reflection surface (340), a third reflection surface (350) and a fourth reflection surface (360) in sequence. The first reflection surface (330) and the second reflection surface (340) are parallel to each other. The third reflection surface (350) and the fourth reflection surface (360) are parallel to each other. The second reflection surface (340) and the third reflection surface (350) are distributed in an eight-shaped shape with the beam opening end facing the exit surface (320). The four laser chips (2) are a first laser chip, a second laser chip, a third laser chip and a fourth laser chip in sequence. The light beam emitted by the first laser chip is incident on an incident surface (310) between a first reflection surface (330) and a second reflection surface (340) through a collimating lens (1), and is transmitted from the incident surface (310) to the first reflection surface (330), firstly turned 90 degrees by the first reflection surface (330) and then reflected to the second reflection surface (340), and then turned 90 degrees by the second reflection surface (340) and then reflected to the exit surface (320); The light beam emitted by the second laser chip is incident on an incident surface (310) located between the second reflection surface (340) and the third reflection surface (350) through a collimating lens (1), and is transmitted from the incident surface (310) to the exit surface (320); The light beam emitted by the third laser chip is incident on an incident surface (310) located between a third reflection surface (350) and a fourth reflection surface (360) through a collimating lens (1), and is transmitted from the incident surface (310) to an exit surface (320); The light beam emitted by the fourth laser chip is incident on the incident surface (310) between the third reflection surface (350) and the fourth reflection surface (360) through the collimating lens (1), and is transmitted from the incident surface (310) to the fourth reflection surface (360), firstly turned 90 degrees by the fourth reflection surface (360) and then reflected to the third reflection surface (350), and then turned 90 degrees by the third reflection surface (350) and then reflected to the exit surface (320).

5. The low-cost 800G 2XFR4 silicon photonics engine according to claim 1, characterized in that: The light-emitting side of the prism (3) is sequentially coupled to an array convergence lens (4), a polarization-independent optical isolator (5) and a silicon photonic chip (6) along the light propagation direction, and the polarization-independent optical isolator (5) is fixed on the side of the silicon photonic chip (6).

6. A low-cost 800G 2XFR4 silicon photonics engine according to claim 1, characterized in that: The light-emitting side of the prism (3) is coupled in sequence along the light propagation direction to a polarization-independent optical isolator (5), an array convergence lens (4) and a silicon photonic chip (6); the polarization-independent optical isolator (5) is fixed on the light-emitting side of the prism (3).

7. The low-cost 800G 2XFR4 silicon photonics engine according to claim 1, characterized in that: The two light-emitting waveguides (620) of the silicon photonic chip (6) are coupled to a dual-channel optical fiber array (7).

8. The low-cost 800G 2XFR4 silicon photonics engine according to claim 1, characterized in that: Each laser chip (2) is respectively fixed on a ceramic heat sink (8).

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