Abstract: The method and device for measuring the spectral phase or combined spectral and spatial phases of ultra short light pulses, consisting of a decomposition of the light pulse to be measured in two identical replicas called signal pulse and primary reference pulse, respectively, of different polarization or direction and the phase characteristics of which are essentially identical to the original pulse, a temporal filtering of the primary reference pulse by a nonlinear interaction generating a secondary reference pulse of average frequency essentially identical and of spectral width greater than the spectral width of the primary reference pulse, and a spectral interferometry measurement by recombination of this secondary reference pulse and the signal pulse with a given temporal offset.

Abstract: The subject matter of the invention is a method of high-resolution acousto-optic programmable filtering in the infrared region of an incident optical wave. To that end it proposes the use of a birefringent acousto-optic crystal whereof the propagation speed of acoustic waves is slow, such as compounds of mercury, which acousto-optic crystal comprises, on one of its faces, a piezoelectric transducer designed to generate a transverse acoustic wave with wave vector whereof the energy propagates according to the same axis but in the opposite direction to the energy of the incident optical wave, knowing that the optical wave resulting from the acousto-optic interaction between the incident optical wave and the acoustic wave with wave vector is diffracted perpendicularly or almost perpendicularly to the direction of the incident optical wave.

Abstract: Device for adaptation of a programmable generator of ultra short wide spectral band light pulses, to long narrow spectral band light pulses comprising a laser source (1) of ultra-short wide spectral band pulses, a device (2) for dispersion of ultra-short pulses output from said laser source (1), a first non-linear optical mixer (4) to mix long modulated pulses output from said dispersion device (2) with long quasi-monochromatic signals output from a pure frequency pump laser (3), a generator (5) of wide spectral band light pulses placed on a first channel (V1), a second non-linear optical mixer (6) to mix the channel output from said generator (5) and a second channel (V2) emerging from said first non-linear optical mixer (4).

Abstract: The subject matter of the invention is a method of high-resolution acousto-optic programmable filtering in the infrared region of an incident optical wave. To that end it proposes the use of a birefringent acousto-optic crystal whereof the propagation speed of acoustic waves is slow, such as compounds of mercury, which acousto-optic crystal comprises, on one of its faces, a piezoelectric transducer designed to generate a transverse acoustic wave with wave vector whereof the energy propagates according to the same axis but in the opposite direction to the energy of the incident optical wave, knowing that the optical wave resulting from the acousto-optic interaction between the incident optical wave and the acoustic wave with wave vector is diffracted perpendicularly or almost perpendicularly to the direction of the incident optical wave.

Abstract: The invention relates to a method and device for controlling the amplitude of the wavelength spectrum of ultra-short light pulses emitted by multipass laser amplifiers. According to the invention, a programmable acousto-optic device (8) is introduced into a laser cavity of a multipass amplifier (10), in order to modify slightly the amplitude of the spectrum of the light pulse with each passage, owing to a collinear or quasi-collinear interaction between the light pulse and a sound beam, the result from the filtering being used on the non-diffracted direct light beam from the acousto-optic interaction.

Abstract: Device for dispersion of light pulses of an optical beam constituted by two dispersive prisms with the same vertex angle, mounted head to tail, the optical input surface of the first prism being parallel to the optical output surface of the second prism, the distance separating the optical input surface of the first prism and the optical output surface of the second prism being adjustable, given that the material constituting at least one of the first and second prisms is an acousto-optic material allowing for acousto-optic interaction between the optical beam and an acoustic beam, the acoustic wave of the acoustic beam generating, in at least one of the first and second prisms, an integrated deflective Bragg cell.

Abstract: A method for measuring ultrashort light pulse which comprises a first step of linear optical filtering of the signal for which it is desired to measure the amplitude of the pulses by means of an acoustic interaction between the optical signal and a colinear or quasi-colinear acoustic beam, a second step of either mixing in a non-linear response electro-optical element of optical beams diffracted by the acoustic beam, followed by one detector for detecting the light intensity derived from the mixer, or effecting one integration detection of the square of the optical intensity diffracted by the acoustic beam.

Abstract: Device for dispersion of light pulses of an optical beam (Fi) constituted by two dispersive prisms (P1, P2), with the same vertex angle (?), mounted head to tail, the optical input surface of the first prism (P1) being parallel to the optical output surface of the second prism (P2), the distance (L) separating said optical input surface of the first prism (P1) and said optical output surface of the second prism (P2) being adjustable, given that the material constituting at least one of said first and second prisms (P1, P2) is an acousto-optic material allowing for acousto-optic interaction between said optical beam and an acoustic beam, the acoustic wave of said acoustic beam generating, in at least one of said first and second prisms (P1, P2), an integrated deflective Bragg cell.

Abstract: The invention relates to a method and device for controlling the amplitude of the wavelength spectrum of ultra-short light pulses emitted by multipass laser amplifiers. According to the invention, a programmable acousto-optic device (8) is introduced into a laser cavity of a multipass amplifier (10), in order to modify slightly the amplitude of the spectrum of the light pulse with each passage, owing to a collinear or quasi-collinear interaction between the light pulse and a sound beam, the result from the filtering being used on the non-diffracted direct light beam from the acousto-optic interaction.

Abstract: A sweep generator circuit generates a primary pulsed voltage and a secondary voltage which are applied to the deflection plates of a streak camera. A primary pulsed voltage generator includes at least one light operated switch for producing deflection of an electron beam in one direction. A secondary voltage generator means generates the secondary voltage which causes deflection of the electron beam in an opposite direction. Variations in the incident light intensity create substantially identical fluctuations in the deflection of the electron beam produced by the primary pulsed voltage and the secondary voltage. Additionally, any variations with respect to time in the deflection of the electron beam produced by the secondary voltage are small in comparison with variations in the deflection of the electron beam produced by the primary pulsed voltage. The sweep generator circuit has an operating point that is stable with respect to variations in the light intensity.