Abstract: An optical system comprises an optical apparatus arranged to direct received light to different paths and to provide a first signal and a second signal, said first and second signals having an optical difference therebetween sufficient for distinguishing optical signals, an amplifier in optical communication with the optical apparatus for amplifying the first and second signals, and a discrimination device to receive amplified light and to provide output light responsive to the optical difference.

Abstract: A method of tuning the time duration of laser output pulses, the method including spectrally dispersing optical pulses and further comprising providing an optical pulse having a time duration and a spectral bandwidth; spectrally dispersing (243, 245) the optical pulse so as to provide a selected change in the time duration of the pulse responsive to the spectral band-width of the pulse; outputting (226) an optical output pulse having a first time duration that is responsive to the selected change in time duration; providing another optical pulse; changing the amount of spectral bandwidth of the another optical pulse (272) to be different than that of the optical pulse or changing the amount of spectral dispersion so that spectrally dispersing the another optical pulse provides a change in time duration that is different than the selected change; and outputting (226) another optical output pulse having a second time duration that is responsive to the different change in time duration, the second time duration

Abstract: An optical source (10) comprising an optical output (12), a pump optical source (14), an optical splitter arranged to receive an optical signal from the pump optical source and to split the optical signal into a pump signal and a seed pump signal. A seed signal forming apparatus (18) is arranged to receive the seed pump signal at the pump wavelength and to transform the seed pump signal into a seed signal at a seed wavelength. A first microstructured optical fibre (MSF1) (20) is arranged to receive the pump signal and the seed signal. MSF1 is arranged to cause the pump signal to undergo four-wave mixing seeded by the seed signal on transmission through MSF1 such that a first optical signal at a signal wavelength and second optical signal at an idler wavelength are generated. One of the signal wavelength and the idler wavelength are the seed wavelength and one of the first and second optical signals are provided to the optical output.

Abstract: A source of femtosecond laser pulses (50) comprising a 980 nm picosecond seed pulse source (12), a Ytterbium (Yb) doped fibre amplifier (14) operating in the three-level regime, a passive air-clad fibre (52) and a pulse compressor (16). The seed pulses are spectrally broadened due to self phase modulation (SPM) in the air-clad Yb doped fibre (18) and further broadened due to SPM in the passive core of the passive air-clad fibre (52), to produce sufficient spectral broadening to allow the pulses to be compressed in the dispersion compensator (16) into femtosecond pulses. The Yb doped fibre may have a phosphosilicate host composition in order to mitigate photodarkening.

Abstract: The subject invention relates to the fabrication of micro-optical structures in a glass-like transparent material using conventional photolithography processing steps. The glass-like material is a spin-on glass (SOG) material, which behaves like a negative-tone photoresist, and has high quality optical properties similar to those of glass. The present invention can take advantage of gray scale photomasks to illuminate the uncured spin-on material with various illumination intensities, thus resulting in variations in resultant film thickness of the SOG material after the chemical development step. This results in micro-optical structures that can be fabricated with the desired shapes, depending on the transmission characteristics of each region of the gray scale photomask.

Abstract: The subject invention relates to the fabrication of micro-optical structures in a glass-like transparent material using conventional photolithography processing steps. The glass-like material is a spin-on glass (SOG) material, which behaves like a negative-tone photoresist, and has high quality optical properties similar to those of glass. The present invention can take advantage of gray scale photomasks to illuminate the uncured spin-on material with various illumination intensities, thus resulting in variations in resultant film thickness of the SOG material after the chemical development step. This results in micro-optical structures that can be fabricated with the desired shapes, depending on the transmission characteristics of each region of the gray scale photomask.