Optical Coupling Adaptor for Optical Signal Coupling Between Photonic Integrated Circuit and Optical Fiber

• US 20170097470A1
• Filed: 10/02/2015
• Published: 04/06/2017
• Est. Priority Date: 10/02/2015
• Status: Abandoned Application

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Jiang, Jia
• Application Number:
  US14/873,733
• Publication Number:
  US 20170097470A1
• Time in Patent Office: Days
• CPC Class Codes: B29D 11/00663 Production of light guides
• CPC Class Codes: B29D 11/0073 Optical laminates
• CPC Class Codes: G02B 2006/12097 Ridge, rib or the like
• CPC Class Codes: G02B 6/00 Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
• CPC Class Codes: G02B 6/1221 made from organic materials
• CPC Class Codes: G02B 6/1228 Tapered waveguides, e.g. integrated spot-size transformers for coupling with fibres G02B6/305
• CPC Class Codes: G02B 6/138 by using polymerisation
• CPC Class Codes: G02B 6/14 Mode converters
• CPC Class Codes: G02B 6/30 for use between fibre and thin-film device
• CPC Class Codes: G02B 6/305 and having an integrated mode-size expanding section, e.g. tapered waveguide
• CPC Class Codes: G02B 6/3636 the mechanical coupling means being grooves G02B6/3652 takes precedence

Abstract

An optical coupling adaptor couples an optical fiber to a photonic integrated circuit (PIC) chip. The adaptor once connected to the PIC chip forms a chip-adaptor assembly. The photonic integrated circuit (PIC) chip has a plurality of inverted taper waveguides having an enlarged optical mode. The optical coupling adaptor has a first section having a plurality of ridge waveguides between layers of cladding and also separated laterally by cladding and a second section abutting the first section, the second section having a plurality of trenches each filled with an optical polymer that Once cured has a refractive index that matches that of the ridge waveguides. The optical coupling adaptor is adhered to the PIC chip using the optical polymer as an adhesive such that the optical polymer in the trenches once cured form polymer waveguides that confine the enlarged mode of the inverted taper waveguides.

Claims

1. An optical coupling adaptor for coupling a photonic integrated circuit (PIC) chip with an optical fiber, the optical coupling adaptor comprising:

a first section having a base layer of cladding, a plurality of ridge waveguides formed on the base layer and separated by cladding, and a top layer of cladding over the ridge waveguides; and

a second section having a base layer of cladding and a plurality of trenches, wherein the trenches abut the ridge waveguides to form continuous waveguides that transmit and confine an enlarged optical mode of inverted taper waveguides of the PIC chip;

wherein the second section connects to the first section and wherein a height of the second section is smaller than a height of the first section.

2. The optical coupling adaptor of claim 1 wherein the trenches are each fillable with an optical polymer that once cured inside the trenches has a refractive index that matches a refractive index of the ridge waveguides.

3. The optical coupling adaptor of claim 1 wherein a cross-sectional area of each trench is equal to a cross-sectional area of each ridge waveguide.

4. The optical coupling adaptor of claim 1 wherein the trenches and ridge waveguides are parallel and equally spaced apart.

5. The optical coupling adaptor of claim 1 wherein the ridge waveguides fan outwardly to match a pitch of an array of optical fibers.

6. The optical coupling adaptor of claim 1 wherein the inverted taper waveguides are silicon waveguides.

7. The optical coupling adaptor of claim 1 wherein the optical polymer is one of polyimide, perfluorinated polymer or polyacrylate.

8. A chip-adaptor assembly comprising:

a photonic integrated circuit (PIC) chip having a plurality of inverted taper waveguides having an enlarged optical mode;

an optical coupling adaptor having;

a first section having a plurality of ridge waveguides between layers of cladding and also separated laterally by cladding; and

a second section abutting the first section, the second section having a plurality of trenches each filled with an optical polymer that once cured has a refractive index that matches that of the ridge waveguides;

wherein the optical coupling adaptor is adhered to the PIC chip using the optical polymer as an adhesive such that the optical polymer in the trenches once cured form polymer waveguides that confine the enlarged mode of the inverted taper waveguides.

9. The chip-adaptor assembly of claim 8 wherein the trenches have a cross-sectional area equal to that of the ridge waveguides.

10. The chip-adaptor assembly of claim 8 wherein the trenches and ridge waveguides are parallel and equally spaced apart.

11. The chip-adaptor assembly of claim 8 wherein the ridge waveguides fan outwardly to match a pitch of an array of optical fibers.

12. The chip-adaptor assembly of claim 8 wherein the inverted taper waveguides are silicon waveguides.

13. The chip-adaptor assembly of claim 8 wherein the optical polymer is one of polyimide, perfluorinated polymer or polyacrylate.

14. A method of making a chip-adaptor assembly for use in coupling a photonic integrated. circuit (PIC) chip to an optical fiber, the method comprising:

providing a photonic integrated circuit (PIC) chip having a plurality of inverted taper waveguides having an enlarged optical mode;

providing an optical coupling adaptor having a first section having a plurality of ridge waveguides between layers of cladding and also separated laterally by cladding and having a second section abutting the first section, the second section having a plurality of trenches;

filling the plurality of trenches with an optical polymer;

mating the optical coupling adaptor with the PIC chip; and

curing the optical polymer to adhere the optical coupling adaptor to the ;

PIC chip to furthermore cause the optical polymer once cured to exhibit a refractive index that matches that of the ridge waveguides to form polymer waveguides that confine the enlarged mode of the inverted taper waveguides.

15. The method of claim 14 wherein the trenches have a cross-sectional area equal to that of the ridge waveguides.

16. The method of claim 14 wherein the trenches and ridge waveguides are parallel and equally spaced apart.

17. The method of claim 14 wherein the ridge waveguides fan outwardly to match a pitch of an array of optical fibers.

18. The method of claim 14 wherein the inverted taper waveguides are silicon waveguides.

19. The method of claim 14 wherein curing the optical polymer comprises curing any one of polyimide, perfluorinated polymer or polyacrylate as the optical polymer.