A variable-wavelength light source is provided with a first laser medium, a first optical resonator constituted of a total reflection mirror and a half-mirror, a second laser medium, a second optical resonator constituted of a total reflection mirror and the half-mirror, a first filter having a pair of first mirrors configured to cause first light and second light to be transmitted and reflected selectively, a second filter having a pair of second mirrors configured to cause the first light and the second light to be transmitted and reflected selectively, a first drive mechanism configured to operate the first mirror and the second mirror in conjunction with each other, and a second drive mechanism configured to operate the second mirror.

In a laser device and a photoacoustic measurement device including the laser device, the intensity of light at each wavelength made independently controllable. The laser device includes a laser medium which has oscillation wavelengths at a first wavelength and a second wavelength with higher light emission efficiency than at the first wavelength, an excitation section, a first resonator, a second resonator, a Q-value change unit, and a control section. The control section oscillates light having the first wavelength through Q switching when a first delay time has elapsed after the excitation of the laser medium has been started in a case where the oscillation wavelength is the first wavelength, and oscillates light having the second wavelength through Q switching when a second delay time has elapsed after the excitation of the laser medium has been started in a case where the oscillation wavelength is the second wavelength.

The present invention provides a dual wavelength optical pulse generator capable of generating an optical pulse dual wavelengths using a thulium-doped optical fiber. A dual wavelength optical pulse generator according to the present invention includes: an optical pump generating a first optical pulse having a first wavelength; an optical resonator generating a second optical pulse having a second wavelength from the first optical pulse generated by the optical pump; a first optical wavelength division multiplexer/demultiplexer supplying the first optical pulse generated by the optical pump to a first end of the optical resonator and separating and outputting the second optical pulse generated by the optical resonator; a delay optical fiber delaying the first optical pulse passed through the optical resonator; and a second optical wavelength division multiplexer/demultiplexer combining: the first optical pulse delayed by the delay optical fiber; and the second optical pulse separated and outputted by the first optical wavelength division multiplexer/demultiplexer to output a dual wavelength optical pulse, wherein the optical resonator comprises: a thulium-doped optical fiber generating the second optical pulse from the first optical pulse; a first fiber Bragg grating provided at a first end of the thulium-doped optical fiber and reflecting the second optical pulse outputted from the first end of the thulium-doped optical fiber; and a second fiber Bragg grating provided at a second end of the thulium-doped optical fiber, the second fiber Bragg grating transmitting the first optical pulse therethrough and reflecting the second optical pulse outputted from the second end of the thulium-doped optical fiber.

A dual frequency laser for a dual mode optical lattice atomic clock is provided, which includes a 532 nm pump laser source, a beam splitter set, a dichroic mirror, a titanium sapphire crystal, a birefringent crystal, an electro-optic crystal, a concave reflector and a PZT. The dichroic mirror and the concave reflector form a first resonant cavity configured to generate a laser; the beam splitter set is configured to split a collimated pump beam into two spatially separated pump beams; an optical axis of the birefringent crystal generates propagation paths for ordinary ray and extraordinary ray within the same cavity to form two eigen modes; the electro-optic crystal is configured to add an electric field externally in a direction parallel to an electric vector of the ordinary ray or the extraordinary ray; and the PZT is combined with the electro-optic crystal to regulate two laser frequencies simultaneously.

Disclosed is a laser apparatus including a laser generator comprising a laser medium, a pumping light source providing light to the laser medium, a first mirror and a second mirror arranged with the laser medium therebetween, and configured to generate a laser beam of a first wavelength, a secondary harmonic wave generator configured to generate a laser beam of a second wavelength from the laser beam of a first wavelength, a light modulator arranged between the laser medium and the secondary harmonic wave generator and configured to adjust a pulse width of the laser beam of a first wavelength, and an output adjustor configured to adjust an output of the laser beam of a second wavelength generated in the secondary harmonic wave generator.