Patent ID: 8411354

Claim:
Optical apparatus, comprising: an oscillator arrangement including a laser cavity for generating modelocked optical pulses from which a sequence thereof, having a predetermined pulse-repetition frequency (PRF), is selected for amplification; an optical amplifier arrangement for amplifying the sequence of optical pulses selected for amplification and delivering a corresponding sequence of amplified pulses; an interferometer for periodically generating, at a maximum frequency less than or equal to the PRF of the sequence of optical pulses, a first signal representative of the instant carrier-envelope phase (CEP) of the pulses in the sequence of amplified pulses; a frequency splitter for dividing the first signal into second and third signals, the second signal including frequency components in a first range between DC and a first frequency less than the maximum frequency, and the third signal including frequency components in a second range between a second frequency less than the maximum frequency and the maximum frequency; a slow-response CEP-controller and a fast-response CEP-controller for adjusting the CEP of the pulses in the sequence of amplified pulses, each of the CEP controllers being located outside of the laser cavity of the oscillator arrangement; a first signal-processing device arranged to receive the second signal, and a second-signal processing device arranged to receive the third signal, the first and second signal processing devices arranged to generate respectively first and second control signals each thereof representative of a difference between the instant and a desired CEP of the pulses in the sequence of amplified pulses, and wherein the first and second control signals adjust respectively the slow-response and fast-response CEP-controllers to minimize the difference between the instant and the desired CEP of the pulses in the sequence of amplified pulses.