Abstract: A wavelength conversion device is disclosed. The wavelength conversion device includes at least a fundamental wave light source and an external resonator, where a reflectance Rin of an input coupling element that inputs light from the fundamental wave light source to the external resonator is selected as represented by the equations 1 and 2, when a frequency jitter of the fundamental wave light source is ?fjitter, a resonator length of the external resonator is Lcav, a frequency line width of the external resonator is ??cav, a total internal loss of the external resonator is ?, and a speed of light is c.

Abstract: A wavelength conversion device is disclosed. The wavelength conversion device includes at least a fundamental wave light source and an external resonator, where a reflectance Rin of an input coupling element that inputs light from the fundamental wave light source to the external resonator is selected as represented by the equations 1 and 2, when a frequency jitter of the fundamental wave light source is ?fjitter, a resonator length of the external resonator is Lcav, a frequency line width of the external resonator is ??cav, a total internal loss of the external resonator is ?, and a speed of light is c.

Abstract: The present invention offers a laser oscillator device having sufficient cooling ability to maintain a lasing medium which generates high-density thermal energy at a temperature appropriate for use, while being capable of being made compact. The laser oscillator device comprises an excitation beam source for generating an excitation beam, a laser medium for receiving the excitation beam and performing optical amplification, a laser oscillator device for causing resonance of light emitted by the laser medium for laser oscillation, and a cooling system for cooling said laser medium, wherein the cooling system uses a gas as the heat-carrying medium.

Abstract: The present invention has the object of offering a laser resonator capable of maintaining high amplification efficiency even if the thermal lensing effect occurring in the laser medium varies during operation or over repeated operation and suspension of the laser device. The laser resonator comprises at least a pair of reflection portions (planar reflective mirrors 3) provided such as to allow a laser beam to oscillate therebetween; a laser medium provided on the optical path of the laser between the pair of reflection portions; an excitation portion (excitation laser device 5) for exciting the laser medium; an optical system (convex lens 1) provided on the optical path of the laser beam between the laser medium and the pair of reflection portions for changing the state of the laser in the laser medium; and a movement portion for moving the optical system along the optical axis of the laser.

Abstract: The invention offers a regenerative optical amplifier enabling voltage to be easily applied to polarizing elements such as Pockels cells, without the need for complicated drive circuitry. An input beam of S-polarized light is reflected by a polarizer 1 and advances to a Pockels cell 2. In the time it takes for the input beam, having once passed through the Pockels cell 2, to be reflected by a reflective mirror 3 and return to the Pockels cell 2, a voltage VP1 causing a 90-degree rotation in the polarization of transmitted light is applied to the Pockels cell 2, and this applied voltage VP1 is maintained. The input beam is converted by the Pockels cell 2 into a P-polarized light pulse which is transmitted by the polarizer.

Abstract: The invention offers a regenerative optical amplifier enabling voltage to be easily applied to polarizing elements such as Pockels cells, without the need for complicated drive circuitry. An input beam of S-polarized light is reflected by a polarizer 1 and advances to a Pockels cell 2. In the time it takes for the input beam, having once passed through the Pockels cell 2, to be reflected by a reflective mirror 3 and return to the Pockels cell 2, a voltage VP1 causing a 90-degree rotation in the polarization of transmitted light is applied to the Pockels cell 2, and this applied voltage VP1 is maintained. The input beam is converted by the Pockels cell 2 into a P-polarized light pulse which is transmitted by the polarizer.

Abstract: The present invention offers a laser oscillator device having sufficient cooling ability to maintain a lasing medium which generates high-density thermal energy at a temperature appropriate for use, while being capable of being made compact. The laser oscillator device comprises an excitation beam source for generating an excitation beam, a laser medium for receiving the excitation beam and performing optical amplification, a laser oscillator device for causing resonance of light emitted by the laser medium for laser oscillation, and a cooling system for cooling said laser medium, wherein the cooling system uses a gas as the heat-carrying medium.

Abstract: The present invention has the object of offering a laser resonator capable of maintaining high amplification efficiency even if the thermal lensing effect occurring in the laser medium varies during operation or over repeated operation and suspension of the laser device. The laser resonator comprises at least a pair of reflection portions (planar reflective mirrors 3) provided such as to allow a laser beam to oscillate therebetween; a laser medium provided on the optical path of the laser between the pair of reflection portions; an excitation portion (excitation laser device 5) for exciting the laser medium; an optical system (convex lens 1) provided on the optical path of the laser beam between the laser medium and the pair of reflection portions for changing the state of the laser in the laser medium; and a movement portion for moving the optical system along the optical axis of the laser.