Abstract: An optical distance measurement or ranging apparatus, the apparatus including at least one optical pulse generator for generating a train of gating pulses and a train of probe pulses, the train of gating pulses having a different repetition rate than the train of probe pulses. The gating and probe pulses may be ultrashort laser pulses generated by different free-running, mode-locked lasers. An optical probing arrangement for directing the train of probe pulses to one or more objects and for collecting returned probe pulses returned from the one or more objects. The objects may include a target object and a reference object. The apparatus includes a multi-photon effect detector and is configured to direct both the train of gating pulses and the returned probe pulses to the multi-photon effect detector. The apparatus may be used for industrial inspection, machine calibration, position measurement or the like.

Abstract: Active FTIR spectroscopy systems and methods for quantitative measurements of concentrations of chemical targets, such as gas, liquid and solid chemical targets, in an open-path measuring arrangement and a method of extracting an effective illumination spectrum of IR light illuminating chemical targets arranged in an open-path measuring arrangement.

Abstract: Active FTIR spectroscopy systems and methods for quantitative measurements of concentrations of chemical targets, such as gas, liquid and solid chemical targets, in an open-path measuring arrangement and a method of extracting an effective illumination spectrum of IR light illuminating chemical targets arranged in an open-path measuring arrangement.

Abstract: A fiber laser having an optical cavity that has an optical fiber and a curved mirror for imaging light leaving the fiber back into the fiber. The optical fiber has a round trip dispersion loss of less than 200000 fs2. The round trip length of the optical fiber is less than 2.3 m.

Abstract: A fibre laser having an optical cavity that has an optical fibre and a curved mirror for imaging light leaving the fibre back into the fibre. The optical fibre has a round trip dispersion loss of less than 200000 fs2. The round trip length of the optical fibre is less than 2.3 m.

Abstract: An optical parametric oscillator (OPO) comprises a resonant cavity for signal light, and an optically non-linear medium disposed in the resonant cavity for converting pump light into the signal light, wherein the resonant cavity is arranged so that in operation signal light is repeatedly output from and returned to the optically non-linear medium along a signal light path in a continuously repeating cycle, and the OPO comprises delay means for extending the time taken for signal light output from the optically non-linear medium in operation to return to the optically non-linear medium along the signal light path.

Abstract: An optical parametric oscillator (OPO) comprises a resonant cavity for signal light, and an optically non-linear medium disposed in the resonant cavity for converting pump light into the signal light, wherein the resonant cavity is arranged so that in operation signal light is repeatedly output from and returned to the optically non-linear medium along a signal light path in a continuously repeating cycle, and the OPO comprises delay means for extending the time taken for signal light output from the optically non-linear medium in operation to return to the optically non-linear medium along the signal light path.

Abstract: There is provided an autocorrelator of ultrashort electromagnetic pulses, comprising an interferometer for receiving a parent electromagnetic pulse from an energy source and for deriving two daughter electromagnetic pulses from the parent pulse, an output means coupled to the interferometer to output the daughter pulses, and a photodiode in communication with the output means to detect the daughter pulses and to alter the frequency thereof so as to produce an electrical output signal that has a quadratic dependence on the power associated with the parent electromagnetic pulse. The temporal duration of the pulses ranges from TO picoseconds to 5 femtoseconds. A GaAsP photodiode is used with a broad band response of 700-1300 nm. The interferometer is either a Michelson interferometer or a Wollaston prism interferometer and a microscope objective is provided between the output means and the photodiode so that the pulses from the output means are focused onto a defined area of the photodiode.