Hsing Chien Cheng

US Patent:

7212708, May 1, 2007

Filed:

Oct 22, 2003

Appl. No.:

10/690858

Inventors:

Hsing Cheng - San Jose CA, US
Hamid R. Khazaei - Westford MA, US
Harmeet Singh - Acton MA, US
Emily M. Squires - Littleton MA, US

Assignee:

JDS Uniphase Corporation - Milpitas CA

International Classification:

G02B 6/34
H04J 14/02

US Classification:

385 37, 385 27, 385 48, 385 14, 385129, 385130, 398 79, 398 82, 398 87, 398 83, 398 91, 398 89, 398 94

Abstract:

In an optical grating device, a grating arrangement receives different wavelength output signals from a plurality of radiation sources at input ports thereof, and generates therefrom a multiplexed wavelength output signal at a zero diffraction order output port of the grating arrangement. Additionally, the gating arrangement generates at least one predetermined wavelength output signal at one of a group consisting of a separate predetermined location in an at least one of a symmetric non-zero diffraction order of the grating arrangement, within the grating arrangement itself, and a combination thereof. A separate power tap is coupled to detect the power of a separate one of the at least one predetermined wavelength output signal from the grating arrangement.

US Patent:

20050175046, Aug 11, 2005

Filed:

Feb 11, 2004

Appl. No.:

10/776808

Inventors:

Hamid Khazaei - Westford MA, US
Hongmin Chen - Acton MA, US
David Lewis - Maynard MA, US
Hsing Cheng - San Jose CA, US

International Classification:

H01S003/13

US Classification:

372029020

Abstract:

In a stabilized laser system, a signal is to be generated at an output thereof having a desired central wavelength. At least one laser, which, while emitting light and having a preselected portion thereof fed back thereto, causes the output signal of the at least one laser source to be shifted in wavelength in a first direction which is spaced apart from the center wavelength of the fed back signal. A feedback generating arrangement is coupled to the at least one laser to process a first portion of the output signal from the at least one laser and generate a feedback signal having a spectral response peaking at a wavelength shifted in an opposite direction to the first direction generated by at least one laser. The feedback signal that is shifted in the opposite direction causes the at least one laser to provide an output signal at the output of the stabilized laser system having a spectral response that peaks essentially at the desired wavelength.

US Patent:

20050175047, Aug 11, 2005

Filed:

Feb 11, 2004

Appl. No.:

10/776809

Inventors:

Hsing Cheng - San Jose CA, US
Hongmin Chen - Acton MA, US
Hamid Khazaei - Westford MA, US

International Classification:

H01S003/13

US Classification:

372029020

Abstract:

In a stabilized laser system, an output of a desired wavelength is generated. Each of a plurality of n lasers, which, while emitting light and having a preselected portion thereof fed back thereto, causes the fed back portion to be amplified and shifted in wavelength in a first direction which is spaced apart from the center wavelength of the feedback signal. A feedback stabilization arrangement is coupled to output ports of the plurality of n lasers for generating a feedback signal having a wavelength spectrum peaking at a wavelength shifted in an opposite direction to the first direction generated by the lasers in response to the feedback signal so as to provide an output signal at the output of the stabilized laser system having a wavelength spectrum that peaks essentially at the desired wavelength. A reflector is located at a predetermined signal round-trip time delay distance from the feedback stabilization arrangement. The reflector receives the output signal from the feedback stabilization arrangement and passes a first portion thereof therethrough, and reflects a remaining second portion back to the feedback stabilization arrangement as a secondary feedback signal that contributes to each of the plurality of n laser sources being set in a stable coherence collapse mode.