Dual lens optical coupling to multicore fiber

Patent metadata

Field	Value
Publication number	US-12442991-B2
Application number	US-202318163806-A
Country	US
Kind code	B2
Filing date	Feb 2, 2023
Priority date	Feb 2, 2023
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

The optical devices described herein include a lens arrangement for coupling light between light sources and optical fibers with a reduced size compared to the use of optical waveguides, while also allowing for the use of power sensitive optical components, such as components with lower power density configurations. The lens arrangements include a collimating lens, a focusing lens, and at least one optical component positioned between the collimating lens and the focusing lens.

First claim

We claim:

1. An optical device comprising:
a first multi-channel laser die comprising a first plurality of laser channels at a first front facet of the first multi-channel laser die;
a lens arrangement comprising:
a first collimating lens aligned to the first front facet;
a focusing lens; and
at least one optical component positioned between the first collimating lens and the focusing lens; and

a multicore optical fiber aligned to the first multi-channel laser die through the lens arrangement and comprising a first plurality of optical cores, wherein the at least one optical component comprises:
a polarization controller device positioned between the first collimating lens and the focusing lens, wherein a plurality of optical signals passing between the first collimating lens and the focusing lens also pass through the polarization controller device, and wherein a plurality of optical signals coupled into the multicore optical fiber from the lens arrangement comprise controlled polarizations.

2. The optical device of claim 1 , wherein the at least one optical component comprises an optical isolator wherein the plurality of optical signals passing between the first collimating lens and the focusing lens also pass through the optical isolator.

3. The optical device of claim 1 , wherein the at least one optical component comprises a power sensitive optical component.

4. The optical device of claim 1 , wherein the multicore optical fiber comprises a polarization-maintaining optical fiber (PMF).

5. An optical device comprising:
a first multi-channel laser die comprising a first plurality of laser channels at a first front facet of the first multi-channel laser die;
a second multi-channel laser die comprising a second plurality of laser channels at a second front facet of the second multi-channel laser die;
a lens arrangement comprising:
a first collimating lens aligned to the first front facet;
a second collimating lens aligned to the second front facet;
a focusing lens; and
at least one optical component positioned between the first collimating lens and the focusing lens; and

a multicore optical fiber aligned to the first multi-channel laser die through the lens arrangement and comprising a first plurality of optical cores.

6. The optical device of claim 5 ,
wherein the first plurality of optical cores are arranged in a first plane, and
wherein the multicore optical fiber comprises:
a second plurality of optical cores arranged in a second plane.

7. The optical device of claim 6 , wherein
a first optical signal comprising a first wavelength and transmitting from the first plurality of laser channels is coupled to a first optical core of the first plurality of optical cores via the lens arrangement, and
a second optical signal comprising a second wavelength and transmitting from the second plurality of laser channels is coupled to the first optical core of the first plurality of optical cores via the lens arrangement.

8. The optical device of claim 5 , wherein the at least one optical component comprises:
a wavelength multiplexing (WM) device wherein a plurality of optical signals passing between the first collimating lens and the focusing lens passes through the WM device, and wherein a plurality of optical signals passing between the second collimating lens and the focusing lens passes through the WM device.

9. The optical device of claim 5 , wherein the at least one optical component comprises:
a polarization multiplexing (PM) device wherein a plurality of optical signals passing between the first collimating lens and the focusing lens passes through the PM device, and wherein a plurality of optical signals passing between the second collimating lens and the focusing lens passes through the PM device.

10. A method comprising:
positioning a first multi-channel laser die on a base structure for an optical device, where the first multi-channel laser die comprises a first plurality of laser channels at a first front facet of the first multi-channel laser die;
aligning a first collimating lens to the first front facet, where a first side of the first collimating lens faces the first front facet;
positioning at least one optical component on a second side of the first collimating lens opposite the first side of the first collimating lens;
positioning a focusing lens on the base structure to place the at least one optical component between the first collimating lens and the focusing lens; and
aligning a multicore optical fiber to the first multi-channel laser die through the first multi-channel laser die and through the focusing lens, the at least one optical component, and the first collimating lens, wherein the at least one optical component comprises:
a polarization controller device positioned between the first collimating lens and the focusing lens, wherein a plurality of optical signals passing between the first collimating lens and the focusing lens passes through the polarization controller device,

wherein positioning the at least one optical component further comprises:
determining a state of polarization for a plurality of optical signals passing into the multicore optical fiber; and
aligning the polarization controller device to control a polarization of the plurality of optical signals passing into the multicore optical fiber from the focusing lens.

11. The method of claim 10 , wherein the at least one optical component comprises an optical isolator wherein a plurality of optical signals passing between the first collimating lens and the focusing lens passes through the optical isolator and wherein positioning the at least one optical component further comprises:
aligning a tilt of the optical isolator within a tilt tolerance for coupling efficiency of the optical device.

12. The method of claim 10 ,
wherein the multicore optical fiber is attached to an optical connector, and
wherein aligning the multicore optical fiber to the first multi-channel laser die comprises attaching the optical connector to the base structure.

13. The method of claim 10 , wherein aligning the first side of the first collimating lens to the first front facet comprises an active alignment process.

14. The method of claim 10 , further comprising:
positioning a second multi-channel laser die on the base structure, where the second multi-channel laser die comprises a second plurality of laser channels at a second front facet of the first multi-channel laser die; and
aligning a second collimating lens to the second front facet, where a first side of the second collimating lens faces the second front facet and a second side of the second collimating lens faces the at least one optical component;
wherein positioning the at least one optical component further comprises:
aligning the at least one optical component to receive collimated beams emitting from the first collimating lens and the second collimating lens; and

wherein the method further comprises:
aligning the multicore optical fiber to the second multi-channel laser die laser die through the focusing lens, the at least one optical component, and the second collimating lens.

15. The method of claim 14 , wherein the multicore optical fiber comprises:
a first plurality of optical cores in a first plane, and
a second plurality of optical cores in a second plane.

16. The method of claim 15 , wherein
aligning the at least one optical component to receive the collimated beams emitting from the first collimating lens and the second collimating lens further comprises:
aligning the at least one optical comp

Assignees

• Cisco Tech Inc

Inventors

• Li Weizhuo
• Schlepple Norbert
• Bovington Jock T

Classifications

• G02B6/4216

  incorporating polarisation-maintaining fibres (polarisation-maintaining fibres per se G02B6/105) · CPC title

• G02B6/4227

  Active alignment methods, e.g. procedures and algorithms · CPC title

• G02B6/29367

  Zigzag path within a transparent optical block, e.g. filter deposited on an etalon, glass plate, wedge acting as a stable spacer · CPC title

• G02B6/4213

  the intermediate optical elements being polarisation selective optical elements (G02B6/27 takes precedence) · CPC title

• G02B6/4215

  the intermediate optical elements being wavelength selective optical elements, e.g. variable wavelength optical modules or wavelength lockers (G02B6/4246 takes precedence) · CPC title