Optical engine receiving structure

Abstract

The invention relates to the technical field of optical communication, in particular to an optical engine receiving structure. The invention provides an optical engine receiving structure which comprises an FA optical fiber array, a lens array, a PD photoelectric detector and a TIA transimpedance amplifier, the lens array, the PD photoelectric detector and the TIA transimpedance amplifier are sequentially arranged in the X direction, the PD photoelectric detector is arranged below the lens array, the lens array is located below the light emitting side of the FA optical fiber array, and the TIA transimpedance amplifier is located below the light emitting side of the lens array. The inclination angle of the inclined plane of the FA optical fiber array is smaller than 45 degrees, and optical fibers of the FA optical fiber array horizontally deflect.

Description

Technical Field

[0001] The present invention relates to the field of optical communication technology, and more specifically, to a light engine receiving structure. Background Art

[0002] The optical engine is the core component for optical signal conversion in optical communication systems. It can also be said to be an integrated optical subsystem, which is generally composed of multiple optical devices and is used to realize the reception, transmission and processing of optical signals. The optical engine usually consists of a laser diode and a modulator, where the laser diode is responsible for generating laser light and the modulator converts electrical signals into optical signals. In optical communication systems, the performance of the optical engine has a direct impact on the transmission quality and rate of the entire system.

[0003] The invention patent with application number 202210177490.7 discloses a multi-channel optical module, in which the receiving optical component disclosed is an integrated optical engine structure, including a receiving end FA (FiberArray), an array lens, an array detector chip, and a TIA chip (Trans-impedance amplifier). The receiving end FA is used to couple the optical signal received by the MPO optical interface to the array lens, and the array lens is used to couple the optical signal to the array detector chip. The array detector chip is used to convert the optical signal into an electrical signal, and the TIA chip is used to amplify the electrical signal to the output standard of the multi-channel optical module. The structure of the above-mentioned integrated optical engine structure is shown in the attached figure. Figure 1 and Figure 2 As shown in , the receiving end FA is horizontally arranged, the array lens is horizontally arranged and located below the receiving end FA, the array detector chip is arranged below the array lens, the TIA chip is located on the side of the array detector chip away from the receiving end FA, the receiving end FA couples the optical signal it receives to the array lens, the optical signal it receives and the output optical signal are located on the same vertical plane, the output optical signal does not tilt in the width direction of the receiving end FA, only when the optical signal passes through the array lens, it tilts in the width direction of the receiving end FA, the receiving end FA tilts in a single direction, and can only perform compensation coupling in a single direction. At the same time, the tilt angle of the receiving end FA is greater than 45° (that is, the tilt angle of the end face of the receiving end FA compared to the vertical plane), the reflected light on the array detector chip will be reflected by the array lens and approach the TIA chip, which will generate optical crosstalk to the TIA chip and affect its normal operation. Summary of the invention

[0004] The object of the present invention is to provide a light engine receiving structure to solve the above problems.

[0005] In order to achieve these purposes and other advantages according to the present invention, a light engine receiving structure is provided, including an FA fiber array, a lens array, a PD photodetector and a TIA transimpedance amplifier, wherein the PD photodetector and the TIA transimpedance amplifier are arranged in sequence along the X direction, and the FA fiber array, the lens array and the PD photodetector are arranged in sequence along the Z direction, the light-emitting side of the FA fiber array faces the lens array, and the light-emitting side of the lens array faces the PD photodetector, and after the light beam of the FA fiber array passes through the lens array and converges onto the PD photodetector, the light beam reflected by the PD photodetector propagates in a direction away from the TIA transimpedance amplifier, so as to avoid the light beam reflected by the PD photodetector from propagating to the TIA transimpedance amplifier after being reflected by the lens array, thereby causing optical crosstalk.

[0006] On the basis of the above technical solution, the present invention can also be improved as follows:

[0007] Furthermore, in the above-mentioned light engine receiving structure, the outgoing light beam of the FA optical fiber array is arranged along the X direction, and the inclination angle of the inclined surface thereof is less than 45°.

[0008] Furthermore, in the optical engine receiving structure, the outgoing light beam of the FA optical fiber array is deflected on the XY plane, and the deflection angle is less than 10°.

[0009] Furthermore, in the above-mentioned light engine receiving structure, the FA optical fiber array includes a V-groove glass base plate, an optical fiber group and a glass cover, the V-groove glass base plate is bonded to the glass cover, and a plurality of V-grooves are provided at one end thereof close to the glass cover, the optical fiber group includes a plurality of optical fibers arranged at equal intervals, and the optical fibers are respectively fixed in the V-grooves.

[0010] Furthermore, in the above-mentioned light engine receiving structure, one end of the glass cover close to the end surface of the FA optical fiber array extends horizontally outward to the inclined surface of the FA optical fiber array.

[0011] Furthermore, in the optical engine receiving structure, the end face of the FA optical fiber array is coated with an anti-reflection film.

[0012] Furthermore, in the light engine receiving structure, the lens on the lens array is a silicon plano-convex lens with a negative magnification, and the spherical surface of the silicon plano-convex lens faces the PD photodetector.

[0013] Furthermore, in the light engine receiving structure, the center of the lens on the lens array and the center of the corresponding PD photosensitive surface on the PD photodetector are offset in the horizontal plane.

[0014] Furthermore, in the optical engine receiving structure, a lens pad is integrally formed at one end of the lower end of the lens array away from the TIA transimpedance amplifier.

[0015] The present invention also provides a method for manufacturing the above-mentioned light engine receiving structure, comprising the following steps:

[0016] S1, fixing the PD photodetector and the TIA transimpedance amplifier on the PCBA;

[0017] S2, performing gold wire bonding on the PD photodetector and the TIA transimpedance amplifier;

[0018] S3, using a high-precision chip mounter to align and mount the lens array and the PD photodetector group;

[0019] S4, coupling the FA optical fiber array and fixing it on the lens array.

[0020] The present invention further provides an optical module, comprising any of the above-mentioned optical engine receiving structures.

[0021] The beneficial effects of the present invention are:

[0022] 1. The tilt angle of the inclined surface of the optical engine receiving structure FA optical fiber array of the present invention is set to less than 45 degrees, so that the reflected light is away from the TIA transimpedance amplifier, reducing optical crosstalk, and compensating coupling from two directions, which can allow a larger misalignment of the lens, improve return loss, and maintain coupling efficiency.

[0023] 2. The light engine receiving structure of the present invention increases the margin of the light spot on the PD photosensitive surface of the PD photodetector, improves the coupling tolerance, makes the amplification smaller, and increases the tolerance.

[0024] 3. The silicon lens array in the optical engine receiving structure of the present invention has the function of a spacer, and the FA optical fiber array can be directly fixed on the silicon lens array. From a process point of view, the silicon lens only needs to be mounted once, avoiding the existing process of mounting spacers multiple times in the industry, thereby improving efficiency, reducing the use of equipment, reducing labor hours and costs, and thus reducing costs.

[0025] 4. In the optical engine structure of the present invention, the FA glass cover completely covers the optical fiber, thereby reducing the probability of the optical fiber being hit and reducing the material defect rate.

[0026] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1It is a side view of the light engine receiving structure described in the background technology of the present invention;

[0028] Figure 2 It is a front view of the light engine receiving structure described in the background technology of the present invention;

[0029] Figure 3 It is a structural schematic diagram of the optical engine receiving structure described in one embodiment of the present invention;

[0030] Figure 4 A side view of a light engine receiving structure according to an embodiment of the present invention;

[0031] Figure 5 A top view of a light engine receiving structure according to an embodiment of the present invention;

[0032] Figure 6 A light path propagation diagram of a light engine according to an embodiment of the present invention;

[0033] Figure 7 A light path propagation diagram of a light engine according to an embodiment of the present invention;

[0034] Figure 8 It is a structural schematic diagram of the FA optical fiber array described in one embodiment of the present invention;

[0035] Fig. 9 is a top view of the FA optical fiber array described in one embodiment of the present invention;

[0036] Fig.10 is a side view of the FA optical fiber array described in one embodiment of the present invention;

[0037] Fig.11 is a schematic structural diagram of a silicon lens array described in an embodiment of the present invention;

[0038] Fig.12 is a schematic structural diagram of a silicon lens array according to another embodiment of the present invention;

[0039] Fig.13 It is a front view of the light engine receiving structure described in another embodiment of the present invention;

[0040] Fig.14 FIG. 4 is a light path propagation diagram of a light engine according to another embodiment of the present invention.

[0041] Wherein, the reference numerals represent:

[0042] FA optical fiber array 1; glass bottom plate 11; optical fiber 12; glass cover 13; inclined surface 14; lens array 2; lens array body 21; silicon plano-convex lens 22; lens pad 23; V-groove 24; groove 25; PD photodetector 3; TIA transimpedance amplifier 4. DETAILED DESCRIPTION

[0043] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0044] It should be noted that, in the description of the present invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc. indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0045] like Figure 3-Figure 5 As shown, a light engine receiving structure includes a FA fiber array 1, a lens array 2, a PD photodetector 3 and a TIA transimpedance amplifier 4, wherein the PD photodetector 3 and the TIA transimpedance amplifier 4 are arranged in sequence along the X direction, and the FA fiber array 1, the lens array 2 and the PD photodetector 3 are arranged in sequence along the Z direction, the light-emitting side of the FA fiber array 1 faces the lens array 2, and the light-emitting side of the lens array 2 faces the PD photodetector 3. After the light beam of the FA fiber array 1 passes through the lens array 2 and converges onto the PD photodetector 3, the light beam reflected by the PD photodetector 3 propagates in a direction away from the TIA transimpedance amplifier 4, so as to avoid the light beam reflected by the PD photodetector 3 being reflected by the lens array 2 and propagating to the TIA transimpedance amplifier 4 to cause optical crosstalk.

[0046] In the above embodiment, in the optical engine receiving structure currently on the market composed of the FA fiber array 1, the lens array 2, the PD photodetector 3 and the TIA transimpedance amplifier 4, the relative positions of the lens array 2, the TIA transimpedance amplifier 4, the PD photodetector 3 and the FA fiber array 1 are fixed, and the FA fiber array 1 couples its received optical signal to the array lens, and the received optical signal and the output optical signal are located on the same vertical plane, and the output optical signal does not tilt in the width direction of the FA fiber array 1, and only the optical signal tilts in the width direction of the FA fiber array 1 when passing through the array lens. At present, the inclination angle of the inclined surface 14 of the FA fiber array 1 is greater than 45°, which causes the optical signal coupled from the FA fiber array 1 to the array lens to be inclined in the direction away from the FA fiber array 1. Similarly, the optical signal coupled from the array lens to the PD photodetector 3 is also inclined in the direction away from the FA fiber array 1. The TIA transimpedance amplifier 4 is located on the side of the PD photodetector 3 away from the FA fiber array 1. Then, part of the optical signal reflected from the PD photodetector 3 will fall on the TIA transimpedance amplifier 4 after being reflected by the lens array 2, causing optical crosstalk to the TIA transimpedance amplifier 4 and affecting its normal operation.

[0047] In order to solve the above problems, the present invention sets the inclination angle of the inclined surface 14 of the FA fiber array 1 to be less than 45°, so that the optical signal coupled from the FA fiber array 1 to the array lens is inclined toward the direction close to the FA fiber array 1, and the optical signal coupled from the array lens to the PD photodetector 3 is also inclined toward the direction close to the FA fiber array 1. Part of the optical signal reflected by the PD photodetector 3 will be reflected by the lens array 2 and will be directed away from the TIA transimpedance amplifier 4, and will not generate optical crosstalk to the TIA transimpedance amplifier 4, thereby ensuring the normal operation of the TIA transimpedance amplifier 4. At the same time, the optical fiber 12 of the FA fiber array 1 is horizontally deflected, so that the received optical signal and the output optical signal of the FA fiber array 1 are not located on the same vertical plane, and are tilted twice in the width direction of the FA fiber array 1, so that the array lens has a larger dislocation space in the width direction of the FA fiber array 1 through compensation coupling in two directions, thereby improving the return loss of the optical engine receiving structure while maintaining the coupling efficiency.

[0048] Specifically, Figure 6-Figure 7 As shown, the arrangement direction of the lens array 2, the PD photodetector 3 and the TIA transimpedance amplifier 4 is taken as the X direction, and an XY horizontal plane is established; the light path propagation path of the light engine is as follows Figure 6-Figure 7As shown, since the inclination angle of the inclined surface 14 of the FA fiber array 1 in the X direction is less than 45°, the light beam is reflected at a reflection angle less than 45° when it is emitted from the inclined surface 14 of the FA fiber array 1, and the centers of the sub-lenses of the lens pass area of ​​the lens array 2 are displaced in a direction close to the TIA transimpedance amplifier 4, as shown in FIG. Figure 6 As shown in , the light beam is inclined and emitted in a direction away from the TIA transimpedance amplifier 4, and then reaches the lens light passing area of ​​the array lens. Due to the converging effect of the lens, the light beam is converged into the photosensitive surface of the PD photodetector 3. Since the coating layer of the PD photosensitive surface of the PD photodetector 3 and the metal pin plate near the photosensitive surface have a certain reflectivity, when the light beam reaches the PD photosensitive surface, a small amount of the light beam is reflected, and the small amount of reflected light propagates in a direction away from the TIA transimpedance amplifier 4, thereby preventing the reflected light from propagating to the TIA transimpedance amplifier 4 and causing optical crosstalk.

[0049] At the same time, in the above embodiment, the inclined surface 14 of the FA optical fiber array 1 is inclined clockwise at an angle less than 10° on the XY plane. When the light beam is emitted from the inclined surface 14 of the FA optical fiber array 1, it is projected in the Y direction, such as Figure 7 As shown in the figure, the light beam is tilted to the right. Since the centers of the sub-lenses in the light-passing area of ​​the lens array 2 are misaligned in the Y direction, the light beam emitted by the FA fiber array 1 is tilted to the right and then passes through the center of the lens, and then is converged to the PD photosensitive surface.

[0050] In summary, since the light beam is tilted in the XY directions, the proportion of the light beam reflected by the PD photosensitive surface and transmitted in the reverse direction returning to the FA optical fiber array 1 is lower, thereby increasing the return loss.

[0051] Preferably, as another embodiment of the present invention, the FA optical fiber array 1 includes a V-groove glass base plate 11, an optical fiber group and a glass cover 13, the V-groove glass base plate 11 is bonded to the glass cover 13, and a plurality of V-grooves are provided at one end thereof close to the glass cover 13, the optical fiber group includes a plurality of optical fibers 12 arranged at equal intervals, and the optical fibers 12 are respectively fixed in the V-grooves.

[0052] In the above embodiment, Figure 8-Figure 10As shown, the FA fiber array 1 is composed of a V-groove glass bottom plate 11, a fiber group, and a glass cover 13. The fiber group has four optical fibers 12, which are arranged at equal intervals and are respectively arranged in the V groove of the V-groove glass bottom plate 11, and are fixed in the V groove by the glass cover 13 and structural adhesive. The glass cover 13 and the V-groove glass bottom plate 11 press the fiber group in the middle to maintain structural stability; finally, at the front end of the FA fiber array 1, an inclined surface 14 is prepared by a grinding and polishing process, and the inclined surface 14 has an inclined angle of less than 45°, that is, the inclined angle of the inclined surface 14 in the X direction is less than 45°. The FA fiber array 1 is tilted at a small angle along the Y direction, and the direction of deflection is not limited. In this embodiment, it is tilted in a clockwise direction, and the tilt angle in the Y direction is not limited. Preferably, the Y axis tilt angle is less than 10°, so that the optical signal output by the FA fiber array 1 propagates in the direction of the tilt angle in both directions; the grinding angle of the inclined surface 14 meets the total reflection angle of the optical fiber 12, and the light beam is totally reflected at the inclined surface 14. In particular, in order to improve the performance, the inclined surface 14 can be coated with a reflection enhancement film. The inclined surface 14 is preferably a plane. Since the inclined surface 14 of the FA fiber array 1 includes the front end faces of the four optical fibers 12, the light beams in the four optical fibers 12 are totally reflected through the inclined surface 14, and the propagation directions of the four reflected light beams are parallel and equidistant.

[0053] Preferably, as another embodiment of the present invention, one end of the glass cover 13 close to the end surface of the FA optical fiber array 1 extends horizontally outward to the inclined surface of the FA optical fiber array.

[0054] In the above embodiment, one end of the glass cover 13 near the end face of the FA fiber array 1 extends horizontally outward to form a small platform, and the small platform reduces the breakage rate of the sharp corner of the front end face of the glass cover 13 during the process. The glass cover 13 completely covers the optical fiber group. Except for the reflection area at the inclined surface 14, the optical fiber group is completely protected by the glass cover 13 and the V-groove glass bottom plate 11. When the sharp corner of the front end face of the glass cover 13 is damaged by collision during the process, only the glass cover 13 is damaged, and the optical fiber group is not damaged, which does not affect the light path propagation, thereby reducing the adverse loss of materials and reducing costs. However, the FA fiber array 1 in the industry, such as Figure 9-10 As shown, the glass cover 13 does not completely cover the optical fiber 12, but reserves a space. When the sharp corner of the FA optical fiber array 1 is hit during the process, the optical fiber 12 body will be damaged, resulting in material defects.

[0055] Preferably, as another embodiment of the present invention, the lens on the lens array 2 is a silicon plano-convex lens 22 with a negative magnification, and the spherical surface of the silicon plano-convex lens 22 faces the PD photodetector 3. A lens pad 23 is integrally formed at one end of the lower end of the lens array 2 away from the TIA transimpedance amplifier 4. As a preferred solution, a gold-tin solder may be provided at the lower end of the lens pad 23. Gold-tin solder is pre-set on the lower surface of the lens pad 23, an identification position is pre-set on the upper end of the lens array 2, and a glue avoidance groove is pre-set between the lower end of the lens array 2, the upper end of the lens array body 21 and the upper end of the lens pad 23.

[0056] In the above embodiment, the lens on the lens array 2 is a silicon plano-convex lens 22, and the spherical surface of the silicon plano-convex lens 22 faces the 3 groups of PD photodetectors. A lens pad 23 is connected to the end of the lens array 2 away from the TIA transimpedance amplifier 4, the lens array body 21 and the lens pad 23 are integrally formed, and the upper end of the lens array body 21 is coplanar with the upper end of the lens pad 23, and the thickness of the lens array body 21 is thinner than the thickness of the lens pad 23. The lens array 2 also includes a V-groove 24, which is located below the lens array body 21 and close to the side of the lens pad 23. The lens array body 21 includes a light-transmitting area and anti-reflection films on the upper and lower surfaces. The light-transmitting area includes the sphere of the lens. When the light engine is assembled, the 3 groups of PD photodetectors are in the V-groove 24 and below the light-transmitting area of ​​the lens array body 21. The optical parameters of the lens body are set to negative magnification, which means that the light emitted from the FA fiber array 1 is reduced after being converged by the lens, the equivalent image distance is less than the equivalent object distance, and the magnification is less than 1. Due to the negative magnification, compared with the conventional positive magnification design in the industry, when the FA fiber array 1 is at the same displacement, the displacement of the converged light with negative magnification at the PD photosensitive surface is smaller, thereby increasing the margin of the converged light spot on the PD photosensitive surface, that is, increasing the coupling tolerance. The sphere of the lens body is located below the lens, making it easier to form a negative magnification of less than 1.

[0057] Preferably, as another embodiment of the present invention, Figure 7 As shown, the center of the lens on the lens array 2 and the center of the corresponding PD photosensitive surface on the PD photodetector 3 are offset in the horizontal plane.

[0058] In the above embodiment, the PD photodetector 3 groups and the lens array 2 are aligned and mounted using a high-precision chip mounter. In order to improve the return loss of the light engine, preferably, the center of each sub-lens of the lens light-passing area of ​​the lens array 2 and the center of each PD photosensitive surface of the PD photodetector 3 group are preset with an XY direction misalignment amount, and the misalignment amount is jointly restricted by the optical parameters of the lens and the inclination angle of the output light beam of the FA fiber array 1 to meet the following conditions: the output light beam of the FA fiber array 1 passes through the center of the light-passing area of ​​the lens array 2 and is converged to the center of the PD photosensitive surface by the lens. Preferably, the center of each sub-lens of the lens light-passing area of ​​the lens array 2 in the present patent is misaligned in the positive direction of the X axis (the direction close to the TIA transimpedance amplifier 4) and the negative direction of the Y axis. Since the inclined output light beam passes through the center of the lens, the aberration caused by the off-axis light beam, such as coma, is avoided, the light spot convergence effect is better, and the energy ratio of the light spot spilling outside the PD photosensitive surface is lower, which improves the coupling efficiency, and further increases the margin of the light spot on the PD photosensitive surface, thereby improving the coupling tolerance.

[0059] The present invention also provides a method for manufacturing the above-mentioned light engine receiving structure, comprising the following steps:

[0060] S1, fixing the PD photodetector 3 and the TIA transimpedance amplifier 4 on the PCBA;

[0061] S2, performing gold wire bonding on the PD photodetector 3 and the TIA transimpedance amplifier 4;

[0062] S3, using a high-precision chip mounter to align and mount the lens array 2 and the PD photodetector 3 groups;

[0063] S4, couple the FA fiber array 1 and fix it on the lens array 2. Specifically, apply UV dual-curing glue on the upper end of the silicon lens array 2, bond and fix the FA fiber array 1 on the lens array 2, and make sure that the glue does not block the light-transmitting area of ​​the silicon lens body when applying the glue. Since the silicon lens array 2 has the function of a cushion block, the FA fiber array 1 can be directly fixed on the upper end of the silicon lens array 2. From a technological point of view, the silicon lens only needs to be mounted once, avoiding the existing multiple pad mounting processes in the industry, thereby improving efficiency, reducing the use of equipment, and reducing labor hours and costs, thereby reducing costs.

[0064] The present invention further provides an optical module, comprising any of the above-mentioned optical engine receiving structures.

[0065] Preferably, as another embodiment of the present invention, Figure 12-13As shown, the lens on the lens array 2 is a silicon plano-convex lens 22, and the spherical surface of the silicon plano-convex lens 22 faces the FA fiber array 1. The end of the lens array 2 away from the TIA transimpedance amplifier 4 is connected to a lens pad 23, the lens array body 21 and the lens pad 23 are integrally processed, and the upper end of the lens array body 21 is coplanar with the upper end of the lens pad 23, and the thickness of the lens array body 21 is thinner than the thickness of the lens pad 23. The lens array 2 also includes a V-shaped groove 24, which is located below the lens array body 21 and on one side of the lens pad 23. The lens array body 21 includes a light-transmitting area, an anti-reflection film at the upper and lower ends, and a groove 25. The light-transmitting area includes a sphere of a lens. The sphere at the upper end of the light-transmitting area is completely retracted inside the groove 25, the area of ​​the groove 25 is smaller than the upper end of the silicon lens array 2, and a certain amount of silicon is reserved around the groove 25 to protect the silicon lens sphere. When the light engine is assembled, the three groups of PD photodetectors are located in the V-groove 24 and below the light-transmitting area of ​​the lens array body 21. The optical parameters of the lens body are set to negative magnification, which means that the light emitted from the FA fiber array 1 is reduced after being converged by the lens, the equivalent image distance is less than the equivalent object distance, and the magnification is less than 1. Due to the negative magnification, compared with the conventional positive magnification design in the industry, when the FA fiber array 1 is at the same displacement, the displacement of the converged light with negative magnification at the PD photosensitive surface is smaller, thereby increasing the margin of the converged light spot on the PD photosensitive surface, that is, increasing the coupling tolerance. Gold-tin solder is pre-set on the lower surface of the lens pad 23. An identification position is pre-set at the upper end of the lens array 2. At the upper end of the lens array 2, a glue avoidance groove is pre-set between the upper end of the lens array body 21 and the upper end of the lens pad 23.

[0066] In this embodiment, the 3 groups of PD photodetectors and the lens array 2 are aligned and mounted using a high-precision chip mounter. In order to improve the return loss of the light engine, preferably, the center of each sub-lens of the lens light-passing area of ​​the lens array 2 and the center of each PD photosensitive surface of the 3 groups of PD photodetectors are preset with an XY direction misalignment amount, and the misalignment amount is jointly restricted by the optical parameters of the lens and the inclination angle of the output light beam of the FA fiber array 1 to meet the following requirements: the output light beam of the FA fiber array 1 passes through the center of the light-passing area of ​​the lens array 2 and is converged to the center of the PD photosensitive surface by the lens. Preferably, the center of each sub-lens of the lens light-passing area of ​​the lens array 2 in this patent is misaligned in the positive direction of the X-axis (the direction close to the TIA transimpedance amplifier 4) and the negative direction of the Y-axis shown in the figure. Since the inclined output light beam passes through the center of the lens, the aberration caused by the off-axis light beam, such as coma, is avoided, the light spot convergence effect is better, and the energy ratio of the light spot spilling outside the PD photosensitive surface is lower, which improves the coupling efficiency, and further increases the margin of the light spot on the PD photosensitive surface, thereby improving the coupling tolerance.

[0067] The light path propagation diagram of the light engine in this embodiment is as follows Fig.14 As shown. Since the inclination angle of the inclined surface 14 of the FA optical fiber array 1 in the X direction is less than 45°, the light beam is reflected at a reflection angle less than 45° when it is emitted from the inclined surface 14 of the FA optical fiber array 1. Fig.14 It can be observed that the light beam is inclined and emitted in a direction away from the TIA transimpedance amplifier 4, and then reaches the lens light passing area of ​​the array lens 121. Due to the converging effect of the lens, the light beam is converged into the photosensitive surface of the PD photodetector group 3. Since the coating layer of the PD photosensitive surface and the metal pin plate near the photosensitive surface have a certain reflectivity, when the light beam reaches the PD photosensitive surface, a small amount of the light beam is reflected, and the small amount of reflected light propagates in a direction away from the TIA transimpedance amplifier 4, thereby avoiding the reflected light from propagating to the TIA transimpedance amplifier 4 and causing optical crosstalk. In the Y direction, it is similar to the previous embodiment and will not be described again.

[0068] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the embodiments shown and described herein.

Claims

1. A light engine receiving structure, comprising an FA fiber array, a lens array, a PD photodetector and a TIA transimpedance amplifier, wherein the PD photodetector and the TIA transimpedance amplifier are arranged in sequence along the X direction, and the FA fiber array, the lens array and the PD photodetector are arranged in sequence along the Z direction, the light-emitting side of the FA fiber array faces the lens array, and the light-emitting side of the lens array faces the PD photodetector. After the light beam of the FA fiber array passes through the lens array and converges onto the PD photodetector, the light beam reflected by the PD photodetector propagates in a direction away from the TIA transimpedance amplifier, so as to avoid the light beam reflected by the PD photodetector being reflected by the lens array and then propagating to the TIA transimpedance amplifier to cause optical crosstalk.

2. The optical engine receiving structure according to claim 1, characterized in that: The outgoing light beam of the FA optical fiber array is arranged along the X direction, and the inclination angle of the inclined surface thereof is less than 45°.

3. The optical engine receiving structure according to claim 2, characterized in that: The outgoing light beam of the FA optical fiber array is deflected on the XY plane, and the deflection angle is less than 10°.

4. The optical engine receiving structure according to claim 1, characterized in that: The FA optical fiber array includes a V-groove glass bottom plate, an optical fiber group and a glass cover. The V-groove glass bottom plate is bonded to the glass cover, and a plurality of V-grooves are provided at one end thereof close to the glass cover. The optical fiber group includes a plurality of optical fibers arranged at equal intervals, and the optical fibers are respectively fixed in the V-grooves.

5. The optical engine receiving structure according to claim 4, characterized in that: One end of the glass cover close to the end surface of the FA optical fiber array horizontally extends outward to the inclined surface of the FA optical fiber array.

6. The optical engine receiving structure according to claim 1, characterized in that: The lenses on the lens array are silicon plano-convex lenses with negative magnification, and the spherical surfaces of the silicon plano-convex lenses face the PD photodetector.

7. The optical engine receiving structure according to claim 6, characterized in that: The center of the lens on the lens array and the center of the corresponding PD photosensitive surface on the PD photodetector are offset in the horizontal plane.

8. The optical engine receiving structure according to claim 1, characterized in that: A lens pad is integrally formed at one end of the lower end of the lens array away from the TIA transimpedance amplifier.

9. A method for manufacturing a light engine receiving structure according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1, fixing the PD photodetector and the TIA transimpedance amplifier on the PCBA; S2, performing gold wire bonding on the PD photodetector and the TIA transimpedance amplifier; S3, using a high-precision chip mounter to align and mount the lens array and the PD photodetector group; S4, coupling the FA optical fiber array and fixing it on the lens array.

10. An optical module, characterized in that: It comprises the light engine receiving structure as described in any one of claims 1 to 8.

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