Optical autocorrelator

摘要

An optical autocorrelator comprises an optical waveguide (40) of semiconductor material which exhibits two photon absorption at a wavelength at which the autocorrelator is intended to operate. Reflecting means (46) are provided at a part of the waveguide which is remote to an end (42) in which an optical pulse (44) is input for reflecting the optical pulse such as to generate counter-propagating optical pulses in the waveguide. A plurality of electrodes (481-48N) are disposed along the waveguide for measuring a two photon absorption photocurrent (i1-in) generated in the waveguide by the counter-propagating optical pulses.