Patents by Inventor Guo P. Li

Guo P. Li has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Multi-wavelength gain-coupled distributed feedback laser array with fine tunability
    Patent number: 5536085
    Abstract: A multi-wavelength laser array having a plurality of gain-coupled distributed feedback ridge waveguide lasers. The operational wavelength of each laser is established by selecting a width of the ridge waveguide in the range 1.6 .mu.m to 5.2 .mu.m. Fine tuning of each central wavelength is achieved by thermal power to selected waveguides via Titanium thin film resistors integrated into the laser array. A wavelength range of 9 nm is demonstrated utilizing a sixteen element array.
    Type: Grant
    Filed: March 30, 1995
    Date of Patent: July 16, 1996
    Assignee: Northern Telecom Limited
    Inventors: Guo P. Li, Toshihiko Makino, Andrew M. Sarangan, Weiping Huang
  • Optical Q-switching to generate ultra short pulses in diode lasers
    Patent number: 5455836
    Abstract: A system for generating an ultra short optical pulse by pumping a semiconductor signal laser with an optical pulse from a semiconductor probe laser. The signal laser has dual segments each operated under different d.c. injection current levels. The probe laser is modulated with a pulsed input and the optical output thereof is coupled via optical means to the signal laser so as to Q-switch the latter. Optical pulses in the 65 ps range result.
    Type: Grant
    Filed: November 23, 1994
    Date of Patent: October 3, 1995
    Assignee: Northern Telecom Limited
    Inventors: Guo P. Li, Toshi Makino, Rongqing Hui
  • Gain-coupled DFB laser with index coupling compensation
    Patent number: 5452318
    Abstract: A gain-coupled distributed feedback (DFB) laser or amplifier structure having a gain-coupling grating in the form of grooves periodically etched through strained, multi-quantum wells. The etched grooves are regrown with buffer material having a bandgap selected to compensate for index-coupling aid to block carrier leakage. The low carrier leakage reduces non-radiative recombination which in turn increases quantum efficiency.
    Type: Grant
    Filed: December 16, 1993
    Date of Patent: September 19, 1995
    Assignee: Northern Telecom Limited
    Inventors: Toshi Makino, Guo P. Li