Abstract: A system is provided for generating a laser beam via non-linear effects, including: a monofrequency continuous-wave laser source; and an external resonant cavity referred to as a microchip cavity. The microchip cavity is composite insofar as it is a unitary assembly of a plurality of materials g: at least one nonlinear crystal; an entrance mirror; a concave mirror deposited on a material fixed to the nonlinear crystal—the material on which the concave mirror is deposited is different from the constituent material of the nonlinear crystal; a first thermoelectric module for controlling the temperature of the nonlinear crystal; and at least one second thermoelectric module for controlling at least the temperature of the material on which the concave mirror is deposited.

Abstract: A system is provided for generating a laser beam via non-linear effects, including: a monofrequency continuous-wave laser source; and an external resonant cavity referred to as a microchip cavity. The microchip cavity is composite insofar as it is a unitary assembly of a plurality of materials g: at least one nonlinear crystal; an entrance mirror; a concave mirror deposited on a material fixed to the nonlinear crystal—the material on which the concave mirror is deposited is different from the constituent material of the nonlinear crystal; a first thermoelectric module for controlling the temperature of the nonlinear crystal; and at least one second thermoelectric module for controlling at least the temperature of the material on which the concave mirror is deposited.

Abstract: A Raman laser device includes: an amplifying medium (2) absorbent at a pump wavelength ?P and emitting at an excitation wavelength ?S, a Raman medium (3) exhibiting at least one Stokes shift ??R, such as to convert the emission at the excitation wavelength ?S into a continuous emission at a Raman wavelength ?R. The amplifying medium and the Raman medium belong to a Raman cavity resonant at the excitation wavelength ?S and at the Raman wavelength ?R. The length of the Raman medium is less than 9 mm and the sum of the gaps between each of the elements of the Raman cavity is less than 2 mm. A system including such a Raman laser device, and a method of adjusting the Raman laser device are described.

Abstract: A laser device includes: an amplifying medium (1, 7) adapted to generate a fundamental wavelength laser beam (13); a birefringent non-linear medium (3, 20, 20) for doubling the fundamental wavelength laser beam to generate a harmonic wavelength laser beam (14); a polarizing medium (1b, 5, 6, 2, 8, 9, 16, 20) for selecting a fundamental wavelength laser beam polarization, the polarizing medium being such that the fundamental wave at its output remains parallel to the fundamental wave at its input. The invention is characterized in that the polarizing medium (1b, 5, 6, 2, 8, 9, 16, 20) has an output side (2b) perpendicular to the fundamental wave exiting the polarizing medium. The amplifying medium, the birefringent non-linear medium are mutually integral so as to constitute a monolithic resonant cavity.

Abstract: An intracavity-doubled laser device, includes a pumping laser-diode, a Nd:YAG amplifying medium stimulated by a laser beam with a fundamental wavelength emitted by the laser diode, the output face of the amplifying medium being cut at the Brewster angle for the fundamental wavelength and a birefringent frequency-doubling KNbO3 crystal. The device further includes an isotropic medium (3), inserted between the input face (8) of the birefringent crystal, the amplifying medium (2) and the birefringent crystal (4), being fixed to each other such as to provide a monolithic resonant cavity. Furthermore, the crystal axis “c” of the birefringent crystal includes a non-zero angle <c with relation to the orthogonal direction of polarization of the fundamental wave defined by the Brewster surface.

Abstract: A laser device includes: an amplifying medium (1, 7) adapted to generate a fundamental wavelength laser beam (13); a birefringent non-linear medium (3, 20, 20) for doubling the fundamental wavelength laser beam to generate a harmonic wavelength laser beam (14); a polarizing medium (1b, 5, 6, 2, 8, 9, 16, 20) for selecting a fundamental wavelength laser beam polarization, the polarizing medium being such that the fundamental wave at its output remains parallel to the fundamental wave at its input. The invention is characterized in that the polarizing medium (1b, 5, 6, 2, 8, 9, 16, 20) has an output side (2b) perpendicular to the fundamental wave exiting the polarizing medium. The amplifying medium, the birefringent non-linear medium are mutually integral so as to constitute a monolithic resonant cavity.

Abstract: The invention concerns a laser device (1, 13) comprising: a three-level amplifying medium (3) adapted to emit a first laser beam (3) of fundamental wavelength; a four-level amplifying medium (5) adapted to emit a second laser beam (7) of fundamental wavelength; a non-linear crystal (4) adapted to mix the first and second beams and to generate a third beam (14, 15) whereof the frequency is the sum of the frequencies of said first and second laser beams. Said device is characterized in that the three-level amplifying medium (3) and at least the non-linear crystal (4) form a resonant cavity for the first laser beam (6), and the four-level amplifying medium (5) and at least the non-linear crystal (4) form a resonant cavity for the second laser beam (7), the two amplifying media and the non-linear crystal forming a linear cavity.

Abstract: The invention relates to an intracavity-doubled laser device, comprising a pumping laser-diode, a Nd:YAG amplifying medium stimulated by a laser beam with a fundamental wavelength emitted by the laser diode, the output face of said amplifying medium being cut at the Brewster angle for said fundamental wavelength and a birefringent frequency-doubling KNbO3 crystal. The device further comprises an isotropic medium (3), inserted between the input face (8) of the birefringent crystal, the amplifying medium (2) and the birefringent crystal (4), being fixed to each other such as to provide a monolithic resonant cavity. Furthermore, the crystal axis “c” of the birefringent crystal includes a non-zero angle <c with relation to the orthogonal direction of polarisation of the fundamental wave defined by the Brewster surface.