CN111367017B

CN111367017B - Waveguide-optical fiber vertical coupling structure on board

Info

Publication number: CN111367017B
Application number: CN202010201936.6A
Authority: CN
Inventors: 韩道森; 王莹; 朱国宜
Original assignee: China Aviation Optical Electrical Technology Co Ltd
Current assignee: China Aviation Optical Electrical Technology Co Ltd
Priority date: 2020-03-20
Filing date: 2020-03-20
Publication date: 2022-05-20
Anticipated expiration: 2040-03-20
Also published as: CN111367017A

Abstract

The invention relates to a waveguide-optical fiber vertical coupling structure on a board, which comprises a daughter board I, a waveguide back board, a plug fixed on the daughter board I, a socket fixed on the waveguide back board, a coupling part packaged in a waveguide port and a waveguide passage arranged on the waveguide back board, wherein the daughter board I is provided with a plurality of through holes; an MT contact piece is assembled in the plug, and a concave mirror or a spherical mirror for realizing vertical light turning is correspondingly arranged on the waveguide end face at one end of each waveguide channel; the socket is fixed on the waveguide back plate and just covers the waveguide port and wraps the coupling part in the socket shell, the head seat is plugged oppositely to enable the MT contact piece and the coupling part to be plugged in and combined, and the optical signal is vertically turned under the action of the concave mirror or the spherical mirror to realize waveguide-optical fiber vertical coupling. The invention can realize the vertical coupling of the waveguide-optical fiber on the board and the no fibrillation on the surface of the waveguide back board, the packaging of the coupling parts is adjusted by means of an MT vertical debugging tool, the operation is easy, and the assembly efficiency is high; the vertical waveguide connector on the board has small installation space and is convenient to maintain.

Description

Waveguide-optical fiber vertical coupling structure on board

Technical Field

The invention relates to a waveguide-optical fiber vertical coupling structure on a board.

Background

Currently, optical signal connection between a back plate and a daughter board inside a case mostly adopts an optical fiber-optical fiber mode. One side of the optical fiber ribbon cable is coupled into the chip or optical module on the backboard, the tail end of the other side of the optical fiber ribbon cable is connected with an optical fiber connector socket, and correspondingly, the daughter board is provided with an adaptive connector plug. The transmission of optical signals between the back plate and the daughter board is realized through the plug-in of the connector head seat. This kind of application form, optical fiber ribbon cable are located the backplate surface more, in case transmission density grade promotes, have that optic fibre distributes in a jumble, density is low, the crooked transmission performance and the reliability that influence of optic fibre, occupy installation space, be unfavorable for shortcoming such as later stage maintenance.

The defects can be overcome by adopting a waveguide-optical fiber coupling mode, the surface of the optical back plate is not fibrillated, and the waveguide-optical fiber low-coupling loss connection is ensured. At present, methods for realizing vertical coupling of waveguide and optical fiber mainly include a coupling element embedding method, a soft waveguide method, a bent optical fiber method, a waveguide grating method and the like. However, these methods are still in the laboratory research stage, and have not yet reached the commercial purpose, and generally have the disadvantages of complex preparation process, high processing precision, low assembly efficiency, poor transmission consistency, low reliability and the like. The on-board waveguide-optical fiber vertical coupling has important significance for realizing on-board optical signal vertical transmission and no fiber on the surface of the optical back plate, and meanwhile, the on-board waveguide-optical fiber vertical coupling has wide application prospect in the field of optical signal transmission.

Disclosure of Invention

The invention provides a waveguide-optical fiber vertical coupling structure on a board, which uses a concave mirror or a spherical mirror to realize vertical steering of optical signals, and in order to realize low-loss transmission of the optical signals and guarantee accurate coupling of the waveguide-optical fiber, the invention simultaneously develops a coupling part with a guide pin, and designs an MT vertical debugging tool for adjusting the packaging position of the coupling part in a waveguide port, and the guide pin of the coupling part is matched with a guide pin hole of an MT contact piece to ensure that the MT contact piece and the coupling part are aligned and inserted, thereby realizing the vertical coupling of the waveguide-optical fiber on the board.

The purpose of the invention and the technical problem to be solved are realized by adopting the following technical scheme. The invention provides a waveguide-optical fiber vertical coupling structure on a board, which comprises a daughter board I, a waveguide backboard, a plug connector fixed on the daughter board I, a socket connector fixed on the waveguide backboard, a coupling part packaged in a waveguide port on the waveguide backboard and a waveguide passage arranged on the waveguide backboard; the plug connector is internally provided with MT contacts, the number of the waveguide paths is equal to the number of cores of the MT contacts, and a concave mirror or a spherical mirror for realizing vertical light steering is correspondingly arranged on the waveguide end face at one end of each waveguide path; the socket connector is fixed on the waveguide backboard and just covers the waveguide port, the coupling part is wrapped in the socket shell, and a guide pin is fixed on the coupling part and is matched with a guide pin hole on the MT contact piece to play a role in guiding the MT contact piece and the coupling part to be inserted and combined; after the plug connector and the socket connector are plugged, the MT contact and the coupling part are aligned and plugged under the guide of the guide pin, and the optical signal is vertically turned under the action of the concave mirror or the spherical mirror, so that the waveguide-optical fiber vertical coupling is realized.

Further, a waveguide core layer in the waveguide backboard is coated on a lower cladding layer on the surface of the PCB board in a spinning mode, and an upper cladding layer is coated on the upper surface of the waveguide core layer and used for protecting the waveguide core layer.

Furthermore, a guide post is arranged on the socket connector, a guide hole matched with the guide post is arranged on the waveguide backboard, and the socket connector is assembled and fixed on the waveguide backboard under the guiding of the matching of the guide post and the guide hole to just cover the waveguide port and wrap the coupling part in the socket shell.

Furthermore, a first glue injection hole and a second glue injection hole are formed in the coupling part, the lower end face of the guide pin is flush with the lower end face of the coupling part, and the guide pin is fixed on the coupling part and is tightly matched with the coupling part by injecting epoxy glue into the first glue injection hole and curing; and UV glue is injected into the second glue injection hole for curing to fix the coupling part in the waveguide port, and epoxy glue is injected into a gap between the coupling part and the waveguide port for secondary reinforcement to ensure the packaging reliability of the coupling part.

Further, the accurate packaging position of the coupling part in the waveguide port is determined through an MT vertical debugging tool, and the MT vertical debugging tool comprises a support fixed on the six-dimensional adjusting frame through a third screw, an MT fixing clamp fixed on a support beam through a fourth screw, a baffle fixed on the MT fixing clamp through a pin, and a spring clamped between the baffle and the MT fixing clamp.

Furthermore, a screw mounting hole II is formed in the support cross beam and used for fixing a fourth screw, one end of the spring is arranged in a round hole in the MT fixing clamp to prevent the spring from shifting, and the other end of the spring is tightly propped against the inner wall of the baffle; the spring action allows the MT contact to be tightly clamped in the MT fixing clip, thereby facilitating the debugging of the packaging position of the coupling part.

Furthermore, two waveguide ports are arranged on the waveguide back plate, the coupling part is packaged in each waveguide port, and each waveguide port is provided with a socket connector to wrap the coupling part in a corresponding socket shell; the waveguide passage is arranged between the two waveguide ports, and the waveguide end surfaces at the two ends of the waveguide passage are respectively provided with a concave mirror or a spherical mirror for realizing the vertical turning of light; the daughter board I and the daughter board II are perpendicular to the waveguide backboard, the plug connectors are fixed on the daughter board I and the daughter board II, the same MT contact is assembled on each plug connector, after the two plug connectors are plugged with the corresponding socket connectors respectively, the MT contact in each plug connector and the coupling part in the corresponding socket are plugged in an aligned mode under the guide of the guide pin, and therefore waveguide-optical fiber vertical coupling on the board is achieved, and optical signals are transmitted from the daughter board I to the daughter board II or from the daughter board II to the daughter board I.

The invention has the beneficial effects that:

the invention provides a coupling part with a guide pin on the basis of realizing waveguide-optical fiber vertical coupling by using a concave mirror or a spherical mirror, designs an MT vertical debugging tool to adjust the position of the coupling part in a waveguide port, and determines the optimal packaging position of the coupling part by adopting power feedback. After the coupling part is debugged and packaged, the guide pin on the coupling part is matched with the guide pin hole of the MT contact element to realize the alignment and insertion of the MT contact element and the coupling part, so that the vertical coupling of the waveguide and the optical fiber on the board is realized. The packaging mode of the coupling part adopts the mode of actively aligning the coupling part and the waveguide port and is matched with an automatic coupling packaging platform, and the MT vertical debugging tool is used for adjustment, so that the operation is easy and the assembly efficiency is high; the packaged coupling parts are lower than the surface of the printed board, the thickness of the original printed board is not increased, the compatibility is high, and the photoelectric composite board is easily formed by pressing the coupling parts with an electric printed board. The invention can realize the non-fibrillation of the surface of the waveguide back plate, has small installation space of the vertical waveguide connector on the plate, is convenient to maintain, greatly reduces the operation difficulty and has wide application prospect.

Drawings

FIG. 1 is a diagram of an example of an application of the structure of the present invention.

Fig. 2 is a structural diagram of a waveguide backplane.

Fig. 3 is a schematic view of a spherical mirror corresponding to the end face of the waveguide.

Fig. 4 is an enlarged view of the waveguide port and the concave mirror cut away.

FIG. 5 is a schematic view of the coupling parts and waveguide port positions.

Fig. 6 is an enlarged view of a portion a in fig. 5.

FIG. 7 is a schematic diagram of debugging the packaging position of a coupled component using an MT vertical debugging tool.

Fig. 8 is an exploded view of fig. 7.

[ reference numerals ]:

1-daughter board I, 2-waveguide backplane, 3-plug connector, 4-receptacle connector, 5-waveguide port, 6-coupling part, 7-waveguide via, 8-MT contact, 9-first screw, 10-second screw, 11-upper cladding, 12-waveguide core layer, 13-lower cladding, 14-PCB printed board, 15-waveguide end face, 16-concave mirror, 17-spherical mirror, 18-screw mounting hole I, 19-guide post, 20-guide hole, 21-first glue injection hole, 22-second glue injection hole, 23-guide pin, 24-daughter board II, 25-third screw, 26-bracket, 27-fourth screw, 28-bracket beam, 29-MT fixing clip, 30-pin, 31-baffle, 32-spring, 33-screw mounting holes II, 34-round hole, 35-six-dimensional adjusting bracket mounting position.

Detailed Description

To further illustrate the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description of the waveguide-fiber vertical coupling structure on board according to the present invention, its specific implementation, features and effects will be made with reference to the accompanying drawings and preferred embodiments.

As shown in fig. 1, the present invention includes a daughter board i 1, a waveguide backplane 2, a plug connector 3 fixed to the daughter board i, a receptacle connector 4 fixed to the waveguide backplane, a coupling component 6 enclosed in a waveguide port 5 on the waveguide backplane, and a waveguide path 7 disposed on the waveguide backplane. The plug connector comprises an MT contact 8 and the like, and is fixed on the daughter board I through a first screw 9. The receptacle connector is fixed to the waveguide backplane by second screws 10.

The waveguide back plate comprises an upper cladding 11, a waveguide core layer 12, a lower cladding 13 and a PCB printed board 14 from top to bottom in sequence, the waveguide back plate adopts a photoetching method to prepare a waveguide layer, as shown in FIG. 2, the waveguide core layer is coated on the lower cladding on the surface of the PCB printed board in a spinning mode, then the waveguide core layer is coated with the upper cladding for protecting the waveguide core layer, and finally a square groove for containing a coupling part, namely a waveguide port, is milled on the waveguide back plate. The waveguide core layer, the upper cladding layer and the lower cladding layer form waveguide channels, the number of the waveguide channels is equal to the number of cores in the MT contact pieces matched with the waveguide core layer, and the center distance of the adjacent waveguide channels is equal to the hole distance of the optical fiber channels of the MT contact pieces. The number of the single-row MT contact cores is 12 or 16, correspondingly, the number of the single-layer waveguide channels of each waveguide port is 12 or 16, and 12 are shown in FIG. 1. The waveguide end face 15 at one end of each waveguide path corresponds to a concave mirror 16 or a spherical mirror 17, preferably a spherical mirror, for achieving vertical turning of the light. When a concave mirror is used, all waveguide end faces of the same waveguide port may also correspond to an integral concave mirror, as shown in fig. 1. The waveguide back plate is further provided with screw mounting holes I18 matched with the second screws 10 and guide holes 20 matched with guide posts 19 on the socket connector for guiding the socket to be assembled on the waveguide back plate. The receptacle connector is assembled and fixed on the waveguide backboard under the guiding of the matching of the guide posts 19 and the guide holes 20 to just cover the waveguide port 5 and wrap the coupling part 6 in the receptacle housing.

The shape and the size of the coupling part are matched with the waveguide port, the packaged coupling part is lower than the surface of the printed board, the thickness of the original printed board is not increased, and the compatibility is high. The coupling part is provided with a first glue injection hole 21 and a second

glue injection hole

22, 4 first glue injection holes and 2 second glue injection holes are arranged in the coupling part, the lower end face of the guide pin 23 is flush with the lower end face of the coupling part, and then the guide pin is fixed on the coupling part and is tightly matched with the coupling part by injecting epoxy glue into the first glue injection holes and placing the guide pin on a drying table for accelerating curing. The guide pins are adapted to cooperate with guide pin holes in the MT contacts to guide the MT contacts and the coupling features into alignment.

The packaging position of the coupling part at the waveguide port is determined through an MT vertical debugging tool, an MT contact part and the coupling part are firstly inserted and combined through guide pins, the MT contact part and the coupling part are assembled and fixed on the MT vertical debugging tool after being inserted and combined, a support on the tool is installed and fixed on a six-dimensional adjusting frame (the six-dimensional adjusting frame is not shown on figures 7-8), the displacement and the angle of the six-dimensional adjusting frame in 6 directions are controlled through an automatic coupling packaging platform, so that the position of the coupling part in the waveguide port is indirectly controlled, at least 2 waveguide channels are monitored simultaneously in a power feedback mode, and the optimal packaging position is determined when the loss power values of all the waveguide channels are minimum. After the coupling part is debugged at the packaging position of the waveguide port, injecting UV glue into second glue injection holes at two sides of the coupling part, curing by using an ultraviolet lamp, fixing the coupling part in the waveguide port on the waveguide back plate preliminarily, then separating the MT contact from the coupling part, withdrawing from a debugging tool, injecting epoxy glue into a gap between the coupling part and the waveguide port for secondary reinforcement, and ensuring the packaging reliability of the coupling part. After the coupling parts are packaged in the waveguide ports, the socket connector is assembled and fixed on the waveguide backboard through a second screw under the guide of the guide pillar of the socket connector and the guide hole on the waveguide backboard, the waveguide ports are just covered, and the coupling parts in the waveguide ports are wrapped in the inner cavity of the socket shell to protect the waveguide end faces to be clean and not influenced by dirt. The MT contact is fitted into the plug housing, which is then fixed to the daughter board i by means of first screws. When the plug is plugged with the socket, the MT contact in the plug and the coupling part packaged in the waveguide port are plugged and combined under the guidance of the guide pin, and the waveguide end face corresponding to the corresponding coupling part is correspondingly provided with a concave mirror or a spherical mirror which can realize the vertical turning of light. Of course, the optical signal of the optical fiber in the MT contact may be vertically steered by the concave mirror or the spherical mirror and then coupled with the waveguide, and then transmitted through the waveguide channel, so as to realize the waveguide-optical fiber vertical coupling on the board. The following examples are given.

As shown in fig. 1, two waveguide ports are disposed on the waveguide backplane, each waveguide port is packaged with the same coupling component, and each coupling component is assembled with a receptacle connector to wrap the coupling component in a corresponding receptacle housing. The waveguide path is arranged between the two waveguide ports, the daughter board I and the daughter board II 24 are perpendicular to the waveguide backboard, plug connectors are fixed on the daughter board I and the daughter board II, and MT contacts with the same number of inserting cores are assembled on each plug connector. After the two plug connectors are mated with the corresponding receptacle connectors, the MT contacts in the plug connectors are mated with the coupling features in the corresponding receptacles as guided by the guide pins 23. Taking the example that the optical signal is transmitted from the daughter board I to the daughter board II, the optical signal in the MT contact fixed on the daughter board I is vertically steered through the concave mirror or the spherical mirror at one end corresponding to the daughter board I and then coupled with the waveguide end face at the end, then the optical signal is transmitted to the concave mirror or the spherical mirror at one end corresponding to the daughter board II through the waveguide passage and is vertically steered through the concave mirror or the spherical mirror and then coupled with the optical fiber in the MT contact on the daughter board II, so that the optical signal is transmitted from the daughter board I to the daughter board II. In other embodiments, the optical signal may be transmitted from daughter board ii to daughter board i via an on-board waveguide-fiber vertical coupling structure.

In the invention, only one MT contact is assembled as an example in the attached figure 1, according to series development conditions, a plurality of MT contacts can be assembled in parallel in a plug connector, a waveguide passage consistent with the total number of cores of the MT contacts is arranged on a waveguide back plate, a concave mirror or a spherical mirror for realizing vertical light turning is arranged on the waveguide end surface at two ends of each waveguide passage, the sizes of a coupling part, a waveguide port, a plug shell and a socket shell are correspondingly increased to adapt to the plurality of parallel waveguide passages and MT contacts, and the optical signal can be transmitted between a daughter board I and a daughter board II by assembling and packaging according to the structure. For example, according to the situation, 2 12-core MT contacts can be assembled in parallel in the plug connector, 24 waveguide channels should be arranged on the waveguide backplane, the sizes of the coupling parts, the waveguide ports, the plug housing and the socket housing are correspondingly increased, and the waveguide-optical fiber vertical coupling and the transmission of optical signals between the daughter board i and the daughter board ii on the series of boards can be completely adapted.

The invention realizes the vertical coupling of waveguide-optical fiber by correspondingly arranging a concave mirror or a spherical mirror on the end surface of the waveguide, designs a coupling part for realizing the low-loss transmission of light and ensuring the accurate coupling of the waveguide-optical fiber, and simultaneously provides an MT vertical debugging tool for realizing the accurate packaging of the coupling part so as to realize the accurate coupling of the waveguide-optical fiber, wherein the MT vertical debugging tool comprises a bracket 26 fixed on a six-dimensional adjusting frame through a third screw 25, an MT fixing clamp 29 fixed on a bracket cross beam 28 through a fourth screw 27, a baffle 31 fixed on the MT fixing clamp through a pin 30 and a spring 32 clamped between the baffle and the MT fixing clamp. The mounting position 35 of the six-dimensional adjusting bracket is shown in fig. 8, a screw mounting hole ii 33 is formed in the bracket beam for fixing a fourth screw, one end of the spring is arranged in a round hole 34 on the MT fixing clamp to prevent the spring from shifting, and the other end of the spring abuts against the inner wall of the baffle. After the baffle is installed, the baffle can rotate around the pin properly under the action of the elastic force of the spring, and when the spring is compressed, the baffle rotates in opposite phases to enable the clamping distance of the MT fixing clamp for clamping the MT contact element to be increased. The MT contact can be tightly clamped in the MT fixing clamp through the spring, so that debugging of the packaging position of the coupling part is facilitated.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention in any way, and any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention by those skilled in the art can be made within the technical scope of the present invention without departing from the technical scope of the present invention.

Claims

1. A waveguide-optical fiber vertical coupling structure on a board is characterized by comprising a daughter board I, a waveguide backboard, a plug connector, a socket connector, a coupling part and a waveguide passage arranged on the waveguide backboard; the plug connector is fixed on the daughter board I, the coupling parts are packaged in the waveguide ports of the waveguide back board, the socket connector is fixed on the waveguide back board and covers the waveguide ports and wraps the coupling parts in the socket shell, MT contact pieces are assembled in the plug connector, the number of waveguide paths is equal to the number of cores of the MT contact pieces, and the waveguide end face of one end of each waveguide path corresponds to a concave mirror or a spherical mirror for realizing vertical light steering; the coupling part is fixed with a guide pin which is matched with a guide pin hole on the MT contact piece to play a role in guiding the MT contact piece and the coupling part to be inserted and combined; after the plug connector and the socket connector are oppositely plugged, the MT contact and the coupling part are aligned and plugged under the guide of the guide pin, and the optical signal realizes vertical steering under the action of the concave mirror or the spherical mirror, so that the waveguide-optical fiber vertical coupling is realized;

the accurate packaging position of the coupling part in the waveguide port is determined through an MT vertical debugging tool, an MT contact element is firstly inserted and combined with the coupling part through guide pins, the MT contact element and the coupling part are assembled and fixed on the MT vertical debugging tool after being inserted and combined, at least 2 waveguide paths are monitored in a power feedback mode, and the optimal packaging position is determined when the loss power values of all the waveguide paths are minimum;

the MT vertical debugging tool comprises a support fixed on a six-dimensional adjusting frame, an MT fixing clamp fixed on a support beam, a baffle fixed on the MT fixing clamp through a pin and a spring clamped between the baffle and the MT fixing clamp; one end of the spring is arranged in a round hole on the MT fixing clamp to prevent the spring from deviating, and the other end of the spring is tightly propped against the inner wall of the baffle; the spring action allows the MT contact to be tightly clamped in the MT fixing clip, thereby facilitating the debugging of the packaging position of the coupling part.

2. The waveguide-fiber vertical coupling structure on board of claim 1, wherein the waveguide core layer in the waveguide backplane is spin coated on the lower cladding layer on the surface of the PCB printed board, the upper cladding layer is coated on the upper surface of the waveguide core layer for protecting the waveguide core layer, the packaged coupling component is lower than the surface of the printed board, and the thickness of the original printed board is not increased.

3. The on-board waveguide-fiber vertical coupling structure according to claim 1, wherein the receptacle connector is provided with a guide post, the waveguide back plate is provided with a guide hole for engaging with the guide post, and the receptacle connector is assembled and fixed on the waveguide back plate under the guiding of the engagement between the guide post and the guide hole to just cover the waveguide port and wrap the coupling component in the receptacle housing.

4. The on-board waveguide-optical fiber vertical coupling structure of claim 1, wherein the coupling component is provided with a first glue injection hole and a second glue injection hole, the lower end surface of the guide pin is flush with the lower end surface of the coupling component, and the guide pin is fixed on the coupling component and tightly fitted with the coupling component by injecting epoxy glue into the first glue injection hole and curing; and UV glue is injected into the second glue injection hole for curing to fix the coupling part in the waveguide port, and epoxy glue is injected into a gap between the coupling part and the waveguide port for secondary reinforcement to ensure the packaging reliability of the coupling part.

5. The on-board waveguide-fiber vertical coupling structure according to claim 1, wherein the waveguide backplane is provided with two waveguide ports, each waveguide port is internally packaged with the coupling component, and each waveguide port is assembled with a socket connector to wrap the coupling component in a corresponding socket housing; the waveguide passage is arranged between the two waveguide ports, and the waveguide end surfaces at the two ends of the waveguide passage are respectively provided with a concave mirror or a spherical mirror for realizing the vertical turning of light; the daughter board I and the daughter board II are perpendicular to the waveguide backboard, the plug connectors are fixed on the daughter board I and the daughter board II, the same MT contact is assembled on each plug connector, after the two plug connectors are plugged with the corresponding socket connectors respectively, the MT contact in each plug connector and the coupling part in the corresponding socket are plugged in an aligned mode under the guide of the guide pin, and therefore waveguide-optical fiber vertical coupling on the board is achieved, and optical signals are transmitted from the daughter board I to the daughter board II or from the daughter board II to the daughter board I.