Optical printed circuit board and its fabrication method

Patent metadata

Field	Value
Publication number	US-2020113045-A1
Application number	US-201816154933-A
Country	US
Kind code	A1
Filing date	Oct 9, 2018
Priority date	Oct 9, 2018
Publication date	Apr 9, 2020
Grant date	—

Abstract

An optical printed circuit board and its fabrication method. The optical printed circuit board includes an electrical conductor arranged for conducting electric signal, an optical waveguide arranged for transmitting optical signal, and an optical waveguide coupling interface arranged at an end of the optical waveguide. The optical waveguide coupling interface is arranged for engagement with an external optical device to optically couple the external optical device with the optical waveguide. The optical waveguide coupling interface includes a first engagement mechanism with a socket defining a space for receiving with a corresponding plug on the external optical device or a plug arranged to be received in a corresponding socket on the external optical device.

First claim

1 . An optical printed circuit board, comprising:
an electrical conductor arranged for conducting electric signal; an optical waveguide arranged for transmitting optical signal; and an optical waveguide coupling interface arranged at an end of the optical waveguide, the optical waveguide coupling interface being arranged for engagement with an external optical device to optically couple the external optical device with the optical waveguide; wherein the optical waveguide coupling interface comprises a first engagement mechanism with:
a socket defining a space for receiving with a corresponding plug on the external optical device; or
a plug arranged to be received in a corresponding socket on the external optical device.

2 . The optical printed circuit board of claim 1 , wherein the space or the plug is generally cylindrical.

3 . The optical printed circuit board of claim 1 , wherein the space or the plug extends in parallel with a corresponding end portion of the optical waveguide.

4 . The optical printed circuit board of claim 1 , wherein the optical waveguide coupling interface comprises a guide member for defining the socket or the plug.

5 . The optical printed circuit board of claim 4 , wherein the guide member has a tubular body that defines the socket.

6 . The optical printed circuit board of claim 5 , wherein the tubular body extends in the optical printed circuit board.

7 . The optical printed circuit board of claim 5 , wherein the tubular body is metallic.

8 . The optical printed circuit board of claim 4 , wherein the guide member has a cylindrical body that defines the plug.

9 . The optical printed circuit board of claim 8 , wherein the cylindrical body extends in and projects from the optical printed circuit board

10 . The optical printed circuit board of claim 8 , wherein the cylindrical body is metallic.

11 . The optical printed circuit board of claim 1 , wherein the optical waveguide coupling interface further comprises a second engagement mechanism with:
a further socket defining a space for receiving with a corresponding plug on the external optical device; or a further plug arranged to be received in a corresponding socket on the external optical device.

12 . The optical printed circuit board of claim ii, wherein the first engagement mechanism and the second engagement mechanism are arranged on opposite sides of the optical waveguide.

13 . The optical printed circuit board of claim 1 , wherein the optical printed circuit board includes a body; the electrical conductor is arranged on or in the body; and the optical waveguide is embedded in the body.

14 . The optical printed circuit board of claim 13 , wherein the body includes a hole and the optical waveguide coupling interface is arranged in the hole.

15 . The optical printed circuit board of claim 1 , wherein the optical waveguide comprises a core and a cladding, wherein the core is made of a material with a first refractive index and the cladding is made of a material with a second refractive index lower than the first refractive index.

16 . The optical printed circuit board of claim 1 , further comprising a further optical waveguide coupling interface arranged at another end of the optical waveguide for engagement with an external optical device to optically couple the external optical device with the optical waveguide.

17 . The optical printed circuit board of claim 1 , further comprising one or more optical waveguides arranged to form an optical waveguide array with the optical waveguide.

18 . The optical printed circuit board of claim 1 , wherein the optical printed circuit board is a single-layer printed circuit board.

19 . The optical printed circuit board of claim 1 , wherein the optical printed circuit board is a multi-layer printed circuit board.

20 . A method for fabricating an optical printed circuit board, comprising:
arranging a first engagement mechanism on a first printed circuit board portion; attaching one or more second printed circuit board portions to the first printed circuit board portion to form an optical printed circuit board with an optical waveguide coupling interface having the first engagement mechanism; wherein the formed optical printed circuit board further includes:
an electrical conductor arranged for conducting electric signal;
an optical waveguide arranged for transmitting optical signal; and
wherein the optical waveguide coupling interface is arranged at an end of the optical waveguide, the optical waveguide coupling interface being arranged for engagement with an external optical device to optically couple the external optical device with the optical waveguide; and wherein the first engagement mechanism includes:
a socket defining a space for receiving with a corresponding plug on the external optical device; or
a plug arranged to be received in a corresponding socket on the external optical device.

21 . The method of claim 20 , wherein arranging the first engagement mechanism on the first printed circuit board portion comprises arranging a guide member on the first printed circuit board portion, wherein the guide member defines the socket or the plug.

22 . The method of claim 21 , further comprising forming a recess on a surface of the first printed circuit board portion prior to arranging a guide member on the first printed circuit board portion; the recess being arranged to at least partly receive the guide member;
and arranging the guide member on the first printed circuit board portion comprises arranging the guide member in the recess on the surface of the first printed circuit board portion.

23 . The method of claim 21 , further comprising forming an optical waveguide on the first printed circuit board portion prior to arranging a guide member on the first printed circuit board portion.

24 . The method of claim 23 , wherein forming the optical waveguide on the first printed circuit board portion comprises:
attaching a cladding portion of the optical waveguide to the surface of the first printed circuit board portion; attaching a core portion of the optical waveguide onto the cladding portion; and attaching a further cladding portion of the optical waveguide onto the core portion.

25 . The method of claim 24 , wherein the core portion is made of a material with a first refractive index; the cladding portion and the further cladding portion are made of a material with a second refractive index lower than the first refractive index.

26 . The method of claim 24 , wherein attaching the cladding portion to the surface of the first printed circuit board portion comprises:
arranging a mold with a surface pattern on the first printed circuit board portion; filling a gap between the mold and the first printed circuit board portion with a material with a first refractive index; heat pressing the mold against the first printed circuit board portion; and curing the material with the first refractive index to form the cladding portion.

27 . The method of claim 26 , further comprising releasing the mold from the first printed circuit board portion after curing.

28 . The method of claim 24 , wherein the cladding portion and the further cladding portion define one or more grooves; and the core portion are arranged in the grooves.

29 . The method of claim 20 , wherein t

Assignees

• Univ City Hong Kong

Inventors

• Chiang Kin Seng
• Lor Kar Pong
• Jin Wei
• Chan Hau Ping

Classifications

• G02B6/3885

  Multicore or multichannel optical connectors, i.e. one single ferrule containing more than one fibre, e.g. ribbon type (optical ribbon cable G02B6/4403, G02B6/448) · CPC title

• G02B6/36

  Mechanical coupling means (G02B6/255, G02B6/42 take precedence) · CPC title

• G02B6/43

  Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections · CPC title

• G02B6/122

  Basic optical elements, e.g. light-guiding paths · CPC title

• H05K1/0274 Primary

  Optical details, e.g. printed circuits comprising integral optical means (H05K1/0269 takes precedence; coupling light guides with opto-electronic components G02B6/42) · CPC title