Abstract: A wavelength conversion laser has: an exciting LD1, a solid state laser including a resonator, and a wavelength conversion element 7 disposed in the resonator. The solid state laser includes a first laser medium and a second laser medium as at least two types of laser media, and is configured to oscillate the solid state laser beams of the first emission wavelength and the second emission wavelength in the resonator as a result of the excitation light entering a region 3 configured from the first laser medium, thereafter entering a region 4 configured from the second laser medium, and subsequently entering a region 5 configured from the first laser medium. The wavelength conversion element 7 simultaneously generates a second harmonic and a sum frequency of the first emission wavelength and the second emission wavelength.

Abstract: A wavelength conversion laser light source includes: a fundamental light source for outputting fundamental light; a wavelength conversion element with a nonlinear optical effect for converting the fundamental light into harmonic light of a different wavelength; a first optical receiver for receiving light of a specific polarization direction contained in the fundamental light output from the fundamental light source and converting an amount of light thereof into an electrical signal; a second optical receiver for receiving the harmonic light output from the wavelength conversion element and converting an amount of light thereof into an electrical signal; a temperature holding unit for holding a temperature of the wavelength conversion element constant; a fundamental light control unit for performing first control of controlling an amount of light of the fundamental light output from the fundamental light source based on the electrical signal from the second optical receiver, and second control of controlling

Abstract: An object of the invention is to increase the beam diameter of a laser beam, and perform high-output wavelength conversion without causing crystal damage. A laser wavelength conversion device includes a laser wavelength conversion element for allowing incidence of a laser beam as a fundamental wave to convert a part of the fundamental wave laser beam into a wavelength-converted laser beam having a wavelength different from a wavelength of the fundamental wave laser beam. The laser wavelength conversion element includes a non-linear optical crystal having periodically polarization reversed portions. The polarization reversed portions are formed in such a manner that a region where a wavelength conversion efficiency is substantially uniform extends in a polarization direction of the non-linear optical crystal. The incident laser beam is converted into the wavelength-converted laser beam with the wavelength conversion efficiency.

Abstract: A wavelength converting apparatus comprising: a laser resonator; a first wavelength converting element that converts a fundamental wave outputted from the laser resonator into a harmonic wave; a first temperature control element that controls the temperature of the first wavelength converting element; a second wavelength converting element that converts a fundamental wave outputted from the first wavelength converting element into a harmonic wave; a second temperature control element that controls the temperature of the second wavelength converting element; a first detecting portion that detects an output of a harmonic wave outputted from the first wavelength converting element; a second detecting portion that detects an output of a harmonic wave outputted from the second wavelength converting element; and a controller that manages temperature control of the first wavelength converting element by the first temperature control element, temperature control of the second wavelength converting element by the seco

Abstract: A wavelength converter is provided with an infrared light source (1) for emitting a fundamental wave having a wavelength of 2000 nm or shorter, a wavelength conversion element (3) composed of a nonlinear optical crystal having a periodical polarization reversal structure and adapted to convert a fundamental wave emitted from the infrared light source (1) into a harmonic wave, and a heater (4) for heating the wavelength conversion element (3). The period of the polarization reversal structure is designed so that a quasi phase matching temperature of the fundamental wave and the harmonic wave is 40° C. or higher. The heater (4) heats the wavelength conversion element (3) to a temperature at which quasi phase matching is established, and the nonlinear optical crystal contains a lithium niobate or lithium tantalate including at least any one of additives Mg, In, Zn and Sc as a main component. Thus, optical damage can be suppressed and visible light absorption attributed to ultraviolet light can be reduced.

Abstract: A short wavelength light source is provided with a fundamental wave light source for generating a fundamental wave, and a plurality of wavelength conversion elements made of nonlinear optical crystals having periodic polarization-inversion structures and adapted to convert a part of the fundamental wave into a second harmonic, and the nonlinear optical crystals of the plurality of wavelength conversion elements are different in material or composition. By converting the fundamental wave from the fundamental wave light source by the plurality of wavelength conversion elements, the generation of a thermal lens effect caused by light absorption can be suppressed to improve a high output resistance.

Abstract: A light source device is provided with a coherent light source for emitting the coherent light, and a pattern changer for changing an interference pattern of the coherent light on a surface of the illumination object. The pattern changer includes a photorefractive crystal which is arranged between the coherent light source and the illumination object and on an optical path of the coherent light and exhibits a photorefractive effect, and a changer for changing at least one of a light intensity distribution, a polarization direction, a wavelength and an intensity of coherent light incident on the photorefractive crystal. The illumination object is illuminated with the coherent light.

Abstract: A laser light source (100) includes a semiconductor laser (101), a wavelength converting element (104) made of a non-linear optical crystal for converting excitation light from the semiconductor laser (101) into wavelength converted light having a wavelength different from the wavelength of the excitation light, a photodiode (109) for measuring a part of the wavelength converted light to be emitted from the wavelength converting element (104) as output light, a photodiode (110) for measuring the excitation light to be emitted from the wavelength converting element (104), and a control circuit (103), wherein the control circuit (103) simultaneously performs an output constant control of making the intensity of the wavelength converted light constant, using a current driving circuit (102), and a temperature control of adjusting the temperature of the wavelength converting element (104), using a heater (105).

Abstract: A wavelength conversion laser is provided with a pair of fundamental wave reflecting surfaces for reflecting a fundamental wave to define a plurality of fundamental wave paths passing a wavelength conversion element at different angles, and a control unit for controlling wavelength conversion efficiencies so that the wavelength conversion efficiency on a specific one of the plurality of fundamental wave paths extending in different directions between the pair of fundamental wave reflecting surfaces is highest.

Abstract: Upon obtaining green light as wavelength converted light by causing infrared light to be incident on a wavelength conversion element, the absorption of the green light occurs due to the generation of ultraviolet light as sum-frequency light of the infrared light and the green light in the wavelength conversion element and the destruction of a crystal composing the wavelength conversion element occurs due to heat generated at this time. In a laser wavelength converter of the present invention, a condensed position of the infrared light in the wavelength conversion element is deviated from a position assumed to be optimal when the influence of the generated heat is ignored. Consequently, crystal destruction is suppressed, a high-efficiency wavelength conversion is enabled and high-output wavelength converted light exceeding several watts, which was difficult to attain in conventional wavelength conversion elements, is attained.

Abstract: A wavelength converting apparatus comprising: a laser resonator; a first wavelength converting element that converts a fundamental wave outputted from the laser resonator into a harmonic wave; a first temperature control element that controls the temperature of the first wavelength converting element; a second wavelength converting element that converts a fundamental wave outputted from the first wavelength converting element into a harmonic wave; a second temperature control element that controls the temperature of the second wavelength converting element; a first detecting portion that detects an output of a harmonic wave outputted from the first wavelength converting element; a second detecting portion that detects an output of a harmonic wave outputted from the second wavelength converting element; and a controller that manages temperature control of the first wavelength converting element by the first temperature control element, temperature control of the second wavelength converting element by the seco

Abstract: A laser light source includes a fundamental laser generator that generates a fundamental laser light, a wavelength conversion element that is made of a ferroelectric crystal with a periodically poled structure and converts the fundamental laser light to a laser light having a different wavelength, a holding member that holds at least a part of an element surface of the wavelength conversion element that crosses a polarization direction of the periodically poled structure, and an insulation layer that is provided between the holding member and the element surface. Electric resistivity of the insulation layer is 1×108 ?·cm or higher.

Abstract: A wavelength converting laser includes: a fundamental-wave laser light source emitting a fundamental wave; and a wavelength conversion element converting the fundamental wave emitted from the fundamental-wave laser light source into a converted wave having a different wavelength from the fundamental wave, in which: a pair of fundamental-wave reflecting surfaces is arranged on both end sides of the wavelength conversion element in the directions of an optical axis thereof and reflects the fundamental wave to thereby pass the fundamental wave a plurality of times inside of the wavelength conversion element, and at least one of the fundamental-wave reflecting surfaces transmits the converted wave; and the pair of fundamental-wave reflecting surfaces allows the fundamental wave to cross inside of the wavelength conversion element and form a plurality of light-concentration points at places different from a cross point of the fundamental wave.

Abstract: A wavelength conversion laser light source includes: an element temperature switching section that switches a temperature of the wavelength conversion element according to a harmonic wave output value as set in an output setting device, and the element temperature switching section for switching a temperature of a wavelength conversion element according to a harmonic wave output level as set in the output setting device, wherein the element temperature switch section includes an element temperature holding section that holds the wavelength conversion element at the temperature as switched by the element temperature switching section.

Abstract: A short wavelength light source is provided with a fundamental wave light source for generating a fundamental wave, and a plurality of wavelength conversion elements made of nonlinear optical crystals having periodic polarization-inversion structures and adapted to convert a part of the fundamental wave into a second harmonic, and the nonlinear optical crystals of the plurality of wavelength conversion elements are different in material or composition. By converting the fundamental wave from the fundamental wave light source by the plurality of wavelength conversion elements, the generation of a thermal lens effect caused by light absorption can be suppressed to improve a high output resistance.

Abstract: An object of the invention is to increase the beam diameter of a laser beam, and perform high-output wavelength conversion without causing crystal damage. A laser wavelength conversion device includes a laser wavelength conversion element for allowing incidence of a laser beam as a fundamental wave to convert a part of the fundamental wave laser beam into a wavelength-converted laser beam having a wavelength different from a wavelength of the fundamental wave laser beam. The laser wavelength conversion element includes a non-linear optical crystal having periodically polarization reversed portions. The polarization reversed portions are formed in such a manner that a region where a wavelength conversion efficiency is substantially uniform extends in a polarization direction of the non-linear optical crystal. The incident laser beam is converted into the wavelength-converted laser beam with the wavelength conversion efficiency.