Abstract: A laser system includes: a laser light source; a light detector configured to output an electric current proportional to an output laser light of the laser light source; a resistor network configured to convert the electric current output from the light detector to a monitor voltage; and a regulator configured to control an intensity of the output laser light based on a comparison between the monitor voltage and a voltage corresponding to a control target value, wherein the resistor network comprises at least two branch circuits connected in parallel with each other, and the branch circuits include respective digital potentiometer circuits commonly formed in a single device.

Abstract: A laser system includes: a laser light source; a light detector configured to output an electric current proportional to an output laser light of the laser light source; a resistor network configured to convert the electric current output from the light detector to a monitor voltage; and a regulator configured to control an intensity of the output laser light based on a comparison between the monitor voltage and a voltage corresponding to a control target value, wherein the resistor network comprises at least two branch circuits connected in parallel with each other, and the branch circuits include respective digital potentiometer circuits commonly formed in a single device.

Abstract: The switching power source circuit (11) for the solid-state laser (100) excited by a semiconductor laser (101) uses a higher switching frequency than the relaxation oscillation (fRO) of the solid-state laser so that the optical noises due to the switching noises or ripples in the output voltage of the switching power source circuit can be minimized. When the voltage drop caused by a semiconductor power device (Q2) is forwarded to a feedback terminal (11b) of the switching power source circuit, even when the forward voltage of the semiconductor laser should vary, the output voltage of the switching power source circuit can be regulated to a value suitable for the driving of the semiconductor laser, and the heat generation from the semiconductor power device can be minimized.

Abstract: A single longitudinal mode diode laser module including a laser diode (1) and an external resonator using a volume holographic grating (3) having a prescribed reflective bandwidth is made amenable to automatic power control by controlling the temperature of the laser diode such that the laser power may be allowed to increase monotonically with an increase in the input current. Therefore, the output laser power can be controlled at a constant level by automatic power control or by adjusting the input current while monitoring the laser power at any desired level of the laser power.

Abstract: A diode laser module includes a laser diode (1), an anamorphic prism pair (5) consisting of a pair of prisms (3, 4) having mutually different apex angles and/or made of material having mutually different refractive indices, and a partial reflective mirror (6; 16) disposed on a side of the anamorphic prism pair away from the laser diode and having a planar or spherical surface facing the anamorphic prism pair and coated with partial reflective coating (6a; 16a). The wavelength of the laser output can be changed by adjusting the position of the partial reflective mirror.

Abstract: A light deflector for deflecting a propagation direction of laser includes: a first metallic piece and a second metallic piece spaced apart from each other; and a transparent medium and an electronic cooling element disposed between the first metallic piece and the second metallic piece such that each of the transparent medium and the electronic cooling element is in contact with the first metallic piece and the second metallic piece. The electronic cooling element creates a temperature difference between the first metallic piece and the second metallic piece to vary a refractive index of the transparent medium.

Abstract: Provided is a diode-pumped solid-state laser adapted for an intracavity sum-frequency mixing for generating a laser radiation of a visible wavelength range by performing a sum-frequency mixing of two laser inputs in a laser resonant cavity. A pair of laser resonators of two different wavelengths are formed along a common optical path and an intracavity sum-frequency mixing is conducted so as to obtain a laser radiation at a sum-frequency wavelength by placing a nonlinear optical crystal on this common optical path. By suitably selecting the properties of the reflective surfaces that form the laser resonators, a laser radiation of a relatively short wavelength range can be obtained even though the wavelength of the pumping laser beam is relatively long, and an extremely high conversion efficiency can be achieved.

Abstract: Provided is a diode-pumped solid-state laser adapted for an intracavity sum-frequency mixing for generating a laser radiation of a visible wavelength range by performing a sum-frequency mixing of two laser inputs in a laser resonant cavity. A pair of laser resonators of two different wavelengths are formed along a common optical path and an intracavity sum-frequency mixing is conducted so as to obtain a laser radiation at a sum-frequency wavelength by placing a nonlinear optical crystal on this common optical path. By suitably selecting the properties of the reflective surfaces that form the laser resonators, a laser radiation of a relatively short wavelength range can be obtained even though the wavelength of the pumping laser beam is relatively long, and an extremely high conversion efficiency can be achieved.

Abstract: In an end pumped or axially pumped solid state laser using a laser diode as a pumping light source, the laser crystal comprises a plurality of individual laser crystals arranged along an axial direction that have progressive higher concentrations of rare earth irons toward the output end. By thus arranging the individual laser crystals containing varying concentrations of rare earth ions, the absorption of laser for each length can be made uniform so that the tolerance for a high power pumping light is increased, and the laser output can be maximized without damaging the laser crystal.