A terahertz wave generating device according to the present invention comprises a fixed-wavelength pump optical laser that generates a single wavelength pump beam, a variable-wavelength laser that emits a seed beam and is capable of making the wavelength of the seed beam variable, a delay element that delays pulses of the pump beam and a first non-linear crystal that generates terahertz waves by receiving the seed beam, a first pump beam that is not delayed by the delay element and a second pump beam that is delayed by the delay element.

Disclosed is a nonlinear optical system for generating or amplifying light pulses by N-wave mixing, including a nonlinear optical medium suitable for receiving at least one first light pulse and one second light pulse. The system includes a fast modulation device for modulating a time delay between the second light pulse and the first pulse light in the nonlinear optical medium, the time delay modulation device being placed upstream of the nonlinear optical medium, and the time delay modulation device being modulated at least between a first delay value and a second delay value, so as to modulate the generation or amplification of a light pulse by N-wave mixing of the at least one first light pulse et one second light pulse in the nonlinear optical medium.

Photonic devices for generating linearly frequency modulated arbitrary microwave signals comprise a laser, and assembly for forming the emitted signal and a photoreceiver the passband of which is in the domain of the microwave frequencies. The forming assembly comprises: a first beam splitter; a first optical channel including a frequency-shifting loop comprising a beam splitter, a first optical amplifier, an optical isolator, a first spectral optical filter and an acousto-optical frequency shifter; a second optical channel including an electro-optical frequency shifter; a second beam splitter; a second optical amplifier; and a second optical filter; the acousto-optical frequency shift, the electro-optical frequency shift and the amplification gain of the first optical amplifier being adjustable.

A light source including: a pulse generator for providing a first sequence of light pulses, the first sequence of light pulses including a first number of light pulses within a predetermined time period, a manipulator configured to generate a second sequence of light pulses from the first sequence of light pulses, the second sequence of light pulses having a second number of light pulses within the predetermined time period, the second number being different from the first number, and a nonlinear optical element arranged to receive the second sequence of light pulses.

This invention removes the need to provide temperature control for an optical time delay chip, which is usually provided by a thermo-electric-cooler, in order to significantly reduce the power dissipation of the device and allow uncooled operation. Uncooled operation is achieved by monitoring the temperature of the chip, and changing the tuning of each microresonator within the device in order to continue providing the required time delay as the temperature is varied. This invention takes advantage of the fact that microresonators provide a series of resonant wavelengths over a wide wavelength range, so that the closest resonance wavelength below the operating wavelength can always be tuned up to that wavelength. When the device temperature changes, this is accounted for by both the choice of resonance wavelengths and the tuning for each of the microresonators in the device, in order to keep the correct tunable delay.

A scanning optical device suitable for use as a camera or solar concentrator.

A terahertz wave generating device according to the present invention comprises a fixed-wavelength pump optical laser that generates a single wavelength pump beam, a variable-wavelength laser that emits a seed beam and is capable of making the wavelength of the seed beam variable, a delay element that delays pulses of the pump beam and a first non-linear crystal that generates terahertz waves by receiving the seed beam, a first pump beam that is not delayed by the delay element and a second pump beam that is delayed by the delay element.

A second harmonic generator may include a combiner to combine a fundamental optical beam with a residual fundamental optical beam. The second harmonic generator may include a second harmonic crystal, coupled to the combiner, to generate a second harmonic optical beam from the fundamental optical beam and the residual fundamental optical beam. Upon generation of the second harmonic optical beam, the residual fundamental optical beam may exit the second harmonic crystal.

A light source including: a pulse generator for providing an initial sequence of light pulses, the pulse generator including an optical source for producing optical pulses; a modulator in communication with the optical source for increasing or decreasing the selected number of pulses provided by the pulse generator in the selected time period; first and second optical arms, for propagating, respectively, first and second sequences of light pulses, wherein the first optical arm includes a first manipulator configured to generate the first sequence of light pulses from the initial sequence of light pulses, wherein the light source includes a nonlinear optical element arranged to receive the first sequence of light pulses or the second sequence of light pulses, and an optical switch arranged to switch either the first sequence of light pulses or the second sequence of light pulses for reception by the nonlinear optical element.

A cascaded harmonic generator, for cascaded optical harmonic generation from an optical beam provided by a laser source, may include a second harmonic generator to generate a second harmonic optical beam based on a residual beam associated with the optical beam. The cascaded harmonic generator may include a third harmonic generator to generate a third harmonic optical beam based on the second harmonic optical beam and the optical beam. The third harmonic generator may be positioned in an optical path upstream from the second harmonic generator. A harmonic generator delay time, associated with the optical path, may be approximately equal to, or may be an approximate integer multiple of, a laser source round-trip time.