Abstract: A method of producing a thermally stable grating allows the grating to be placed in environments where temperatures reach 1000° C. and where the grating is relatively stable and has very low loss from scatter. These gratings have spectral characteristics that allow them to be concatenated so as to form a sensor array. The method requires a step of lowering the characteristic intensity threshold of a waveguide by at least 25%, followed by irradiating the waveguide with femtosecond pulses of light having a sufficient intensity and for a sufficient duration to write the grating so that at least 60% of the grating remains after exposures of at least 10 hours at a temperature of at least 1000° C.
Type:
Grant
Filed:
June 18, 2009
Date of Patent:
September 25, 2012
Assignee:
Her Majesty the Queen in right of Canada, as represented by the Minister of Industry, through the Communications Research Centre Canada
Inventors:
Christopher W. Smelser, Stephen J. Mihailov, Dan Grobnic, Ping Lu, Robert B. Walker, Gino Cuglietta, Haimin Ding, Xiaoli Dai