Multi-beam free space optical endpoint

Patent metadata

Field	Value
Publication number	US-9350448-B2
Application number	US-201314095247-A
Country	US
Kind code	B2
Filing date	Dec 3, 2013
Priority date	Dec 3, 2013
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

Free space optics (FSO) is a wireless technology that utilizes optical frequencies. Previously available FSO transceivers are restricted to point-to-point links because of the high directivity of laser light used to transmit data. By contrast, various implementations disclosed herein include a multi-beam FSO apparatus that is less reliant on point-to-point links, and includes a lens assembly and a planar array of optical communication devices. The lens assembly includes at least one surface shaped to direct ingress light received substantially within a first angular range towards a focal plane, and to direct egress light away from the focal plane into the first angular range. The planar array includes a plurality of optical communication devices arranged in association with the focal plane of the lens assembly, wherein each of the plurality of optical communication devices characterizes at least one of a plurality of optical communication link endpoints.

First claim

What is claimed is:

1. An apparatus comprising:
a lens assembly including at least one surface shaped to direct ingress light received substantially within a first angular range towards a focal plane, and to direct egress light away from the focal plane into the first angular range;
a planar array including a plurality of optical communication devices arranged in association with the focal plane of the lens assembly, wherein each of the plurality of optical communication devices characterizes at least one of a plurality of optical communication link endpoints, wherein the plurality of optical communication devices comprises a plurality of light transmission devices, wherein each of the plurality of light transmission devices is controllable to modulate a respective beam of egress light to include transmission data onto a corresponding optical communication link occupying a specific portion of the first angular range;
a first substrate including a first subset of the plurality of optical communication devices; and
a second substrate including a second subset of the plurality of optical communication devices, and
wherein the first substrate is perforated to include perforations that permit a plurality of beams of light to pass to or from the second subset of the plurality of optical communication devices of the second substrate.

2. The apparatus of claim 1 , wherein the first angular range comprises a range between 10 and 200 degrees spanning at least one dimension.

3. The apparatus of claim 1 , wherein the lens assembly directs a beam of ingress light received within a respective portion of the first angular range to a corresponding respective area on the focal plane that is associated with at least one of the plurality of optical communication devices, and directs a beam of egress light away from the at least one of the plurality of optical communication devices into the corresponding respective portion of the first angular range.

4. The apparatus of claim 3 , wherein each respective portion of the first angular range and the corresponding respective area on the focal plane characterize at least a portion of a respective optical communication link associated with at least one of the plurality of optical communication link endpoints.

5. The apparatus of claim 1 further comprising a filter that is configured to at least one of reduce the amount of egress light reflected back to the focal plane, substantially reject ambient light and condition ingress light directed to a plurality of photo-detectors.

6. The apparatus of claim 5 , wherein the filter is characterized by at least one of being configured to effect beam forming, being wavelength sensitive, being anti-reflective, including a quarter-wave plate, and a coating on the at least one surface of the lens assembly.

7. The apparatus of claim 1 , wherein the plurality of light transmission devices is manufactured on the first substrate.

8. The apparatus of claim 7 wherein the second substrate includes a plurality of photo-detectors, and wherein the first substrate is suitable for light transmission device manufacturing.

9. The apparatus of claim 8 , wherein the plurality of light transmission devices and the plurality of photo-detectors are arranged as a plurality of device groups, wherein each of the plurality of device groups includes at least one of each of the plurality of light transmission devices and the plurality of photo-detectors.

10. The apparatus of claim 8 , wherein some of the plurality of light transmission devices and some of the plurality of photo-detectors are substantially uniformly arranged in the planar array forming at least one of a hexagonal ring arrangement, a fractal pattern, and a grid pattern.

11. The apparatus of claim 7 , wherein the first substrate is a silicon-based substrate, and the plurality of light transmission devices are bonded to the silicon-based substrate.

12. The apparatus of claim 7 , further comprising planar optics arranged between the lens assembly and the plurality of light transmission devices, wherein the planar optics are configured to provide at least one of egress light beam geometry shaping and beam correction.

13. The apparatus of claim 1 , wherein the plurality of optical communication devices comprises a plurality of photo-detectors, wherein each of the plurality of photo-detectors is controllable to receive modulated ingress light including reception data from a corresponding optical communication link.

14. The apparatus of claim 1 , further comprising a control module coupled to the plurality of optical communication devices, wherein the control module configured to manage and provide an external interface for the plurality of optical communication link endpoints, and includes at least one of a processor, digital logic, programmable firmware, and an allocation of memory.

15. The apparatus of claim 14 , wherein the control module is configured to provide at least one of protocol processing, modulation, demodulation, data buffering, power control, routing, switching, clock recovery, amplification, decoding, and error control.

16. The apparatus of claim 14 further comprising a first substrate including at least a portion of the control module and at least a portion of the plurality of optical communication devices.

Assignees

• Cisco Tech Inc
• Cisco Tech Inc

Inventors

• Byers Charles Calvin

Classifications

• H04B10/1125 Primary

  using a single common optical path · CPC title

• H04B10/1149

  Arrangements for indoor wireless networking of information · CPC title

• H04B10/1143

  Bidirectional transmission · CPC title

• H04B10/1129

  Arrangements for outdoor wireless networking of information · CPC title