Multi-channel optical receiver or transmitter with a ball lens

Patent metadata

Field	Value
Publication number	US-9692522-B2
Application number	US-201514687702-A
Country	US
Kind code	B2
Filing date	Apr 15, 2015
Priority date	Apr 15, 2015
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

Embodiments herein describe an optical receiver that demultiplexes a multi-wavelength optical signal into a plurality of optical signals with respective wavelengths. Stated differently, the various wavelengths in the received optical signal are separated into different optical signals with different wavelengths. In one embodiment, the optical receiver includes a plurality of optical filters that is aligned with a mirror to perform the demultiplexing function. The embodiments herein disclose optical receivers where the optical components performing the demultiplexing function using a ball lens aligned with optical filters.

First claim

We claim:

1. An optical receiver, comprising:
an optical source configured to transmit a multiplexed optical signal including a first data signal comprising a first wavelength and a second data signal comprising a second, different wavelength;
a first optical filter arranged to receive the multiplexed optical signal from the optical source, wherein a material of the first optical filter permits the first data signal to pass through the first optical filter and reflects the second data signal;
a mirror arranged to receive the second data signal reflected from the first optical filter and redirect the second data signal;
a second optical filter arranged to receive the second data signal after being reflected by the first optical filter, wherein a material of the second optical filter permits the second data signal to pass through the second optical filter; and
a ball lens configured to receive the first and second data signals after passing through the first and second optical filters and focus the first and second data signals onto individual detectors.

2. The optical receiver of claim 1 , further comprising:
a photodiode array comprising the detectors, wherein the photodiode array is electrically connected to an integrated circuit.

3. The optical receiver of claim 2 , wherein the first data signal strikes the photodiode array in a first direction that is perpendicular to a surface of the photodiode array facing the ball lens, and wherein the second data signal strikes the photodiode array in a second direction that is not perpendicular to the surface.

4. The optical receiver of claim 2 , wherein both the first and second data signals strike the photodiode array in a direction that is not perpendicular to a surface of the photodiode array facing the ball lens.

5. The optical receiver of claim 1 , further comprising:
a prism disposed between the ball lens and first and second optical filters, wherein the first and second data signals pass through the prism before reaching the ball lens.

6. The optical receiver of claim 1 , wherein both the first and second data signals pass through a center of the ball lens.

7. The optical receiver of claim 1 , further comprising a printed circuit board electrically coupled to the detectors, wherein the printed circuit board extends away from the ball lens in a direction that is parallel with an optical path traveled by the first data signal when propagating from the first optical filter to the ball lens.

8. The optical receiver of claim 1 , further comprising a printed circuit board electrically coupled to the detectors, wherein the printed circuit board extends away from the ball lens in a direction that is offset with an optical path traveled by the first data signal when propagating from the first optical filter to the ball lens.

9. The optical receiver of claim 1 , further comprising:
a third optical filter arranged to receive a third data signal of the multiplexed optical signal, the third data signal comprises a third wavelength different from the first and second wavelengths, wherein a material of the third optical filter permits the third data signal to pass through the third optical filter, and wherein, after passing through the third optical filter, the third data signal is received by the ball lens.

10. A method of fabricating an optical receiver, the method comprising:
disposing, in the optical receiver, an optical source for transmitting a multiplexed optical signal including a first data signal comprising a first wavelength and a second data signal comprising a second, different wavelength;
disposing, in the optical receiver, a first optical filter for receiving the multiplexed optical signal from the optical source, wherein a material of the first optical filter permits the first data signal to pass through the first optical filter and reflects the second data signal;
disposing, in the optical receiver, a mirror for receiving the second data signal reflected from the first optical filter and redirecting the second data signal;
disposing, in the optical receiver, a second optical filter for receiving the second data signal after being reflected by the first optical filter, wherein a material of the second optical filter permits the second data signal to pass through the second optical filter; and
disposing, in the optical receiver, a ball lens for receiving the first and second data signals after passing through the first and second optical filters and focusing the first and second data signals onto individual detectors.

11. The method of claim 10 , wherein disposing the first and second optical filters in the optical receiver comprises:
passively aligning the first and second optical filters using one or more alignment features in the optical receiver; and
attaching the first and second optical filters to a housing of the optical receiver after being passively aligned.

12. The method of claim 11 , wherein the passive alignment is performed without transmitting any test optical signal in the optical receiver.

13. The method of claim 10 , wherein disposing the mirror in the optical receiver comprises:
actively aligning the mirror after disposing the first optical filter, second optical filter, and ball lens in the optical receiver; and
attaching the mirror to a housing of the optical receiver after being actively aligned.

14. The method of claim 13 , wherein the active alignment is performed by transmitting a test optical signal through the optical receiver and measuring a resulting electrical signal using at least one of the detectors.

15. The method of claim 10 , further comprising:
attaching a flex sub-assembly comprising a printed circuit board and the detectors to a housing in the optical receiver, wherein the housing includes the first and second optical filters, the mirror, and the ball lens.

16. The method of claim 15 , wherein the mirror is disposed in the optical receiver after attaching the flex sub-assembly to the housing.

17. The method of claim 10 , further comprising:
actively aligning, in the optical receiver, a receptacle to the optical source; and
attaching the receptacle to a housing of the optical receiver after being actively aligned.

18. An optical receiver, comprising:
an optical source configured to transmit a multiplexed optical signal including a first data signal comprising a first wavelength and a second data signal comprising a second, different wavelength;
an optical filter arranged to receive the multiplexed optical signal from the optical source, wherein a material of the optical filter permits the first data signal to pass through the optical filter and reflects the second data signal;
a mirror arranged to receive the second data signal reflected from the optical filter and redirect the second data signal; and
a ball lens configured to receive the first data signal after passing through the optical filter, receive the second data signal after being redirected by the mirror, and focus the first and second data signals onto individual detectors.

19. The optical receiver of claim 18 , further comprising:
a photodiode array comprising the detectors, wherein the photodiode array is electrically connected to an integrated circuit.

20. The optical receiver of claim 19 , wherein the first data signal strikes the photodiode array in a first direction that is perpendicular to a surface of the photodiode array facing the ball lens, and wherein the second data signal strikes the photodiode array in a second direction th

Assignees

• Cisco Tech Inc

Inventors

• Pfnuer Stefan Martin
• Sun Pang-Chen

Classifications

• G02B6/2938

  for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM · CPC title

• H04B10/676 Primary

  for all-optical demodulation of the input optical signal · CPC title

• G02B6/4214

  the intermediate optical element having redirecting reflective means, e.g. mirrors, prisms for deflecting the radiation from horizontal to down- or upward direction toward a device (G02B6/4246 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

• G02B6/4206

  Optical features (G02B6/4207, G02B6/421 take precedence) · CPC title