Abstract: When the laser light source is caused to standby, the temperatures of semiconductor laser 1 and semiconductor laser 9 are changed by approximately 3° C. from the temperature when the laser light source is always being used. With a temperature change of approximately 3° C., the wavelengths of the laser light generated by semiconductor lasers 1 and 9 change approximately 0.3 nm. This change hardly has any effect at all on optical fiber amplifier 2 and optical fiber amplifier 10, but the conversion efficiencies at the respective wavelength conversion elements of the wavelength conversion optical system change, and, particularly, deep ultraviolet light is hardly generated at all any longer. Therefore, even while the laser light has been made incident to the wavelength conversion optical system, there is no longer damaging of the wavelength conversion elements. Therefore, it is possible to provide a laser light source standby method that is able to shorten the start up time of the laser light source.

Abstract: In nonlinear optical crystal 183D, each step of wavelength conversion can be performed using another fundamental wave that is output from light output unit 1612, without using the fundamental wave whose output level has been attenuated after going through wavelength conversion for several steps (wavelength conversion in nonlinear optical crystals 183A to 183C). Therefore, the wavelength conversion efficiency improves and the peak power of optical amplifiers 1611 and 1612 can be suppressed, which allows the wavelength of lights that are output from optical amplifiers 1611 and 1612 to be further narrowed.

Abstract: The present invention relates to an optical fiber for amplification, an optical amplifying apparatus, and so on, having a structure for enabling increase of power of output light, suppression of occurrence of nonlinear optical phenomena, and compact storage all together. The optical amplifying apparatus comprises an optical fiber for amplification amplifying input light inputted together with pumping light from a pumping light source. The optical fiber for amplification comprises a core region doped with a rare-earth element, and a cladding region provided on an outer periphery of the core region and having a refractive index lower than that of the core region. The core region has an outer diameter of 10 ?m or more but 30 ?m or less, and has a relative refractive index difference of 0.5% or more but 2.0% or less with respect to the cladding region. The cladding region has an outer diameter of 75 ?m or more but 200 ?m or less.

Abstract: A fifth harmonic wave is formed from a fundamental wave of P polarization via a second harmonic wave forming optical element 3, a third harmonic wave forming optical element 4, and a fifth harmonic wave forming optical element 6, and a second harmonic wave of P polarization is formed from a fundamental wave of P polarization via a second harmonic wave forming optical element 9. A fundamental wave of S polarization is combined with the second harmonic wave of P polarization described above by a dichroic mirror 13; furthermore, the fifth harmonic wave of P polarization, the fundamental wave of S polarization described above and the second harmonic wave of P polarization are combined by a dichroic mirror 10, and are incident on a seventh harmonic wave forming optical element 11.

Abstract: An ultraviolet light source (1) comprises a laser light source (10) for generating a signal light in the infrared region, a optical amplifier (20) which comprises fiber optical amplifiers (21, 22) and amplifies the signal light generated by the laser light source (10), and a wavelength converting optical system (30) which coverts the signal light amplified by the light amplifier (20) into an ultraviolet light and outputs the converted light. The ultraviolet light source (1) uses a single-mode fiber laser (26) as an excitation light source for at least the fiber optical amplifier (22) at one stage of the optical amplifier (20).

Abstract: A fifth harmonic wave is formed from a fundamental wave of p-polarized light via a second harmonic wave forming optical element 3, a third harmonic wave forming optical element 4, and a fifth harmonic wave forming optical element 6 and a second harmonic wave of p-polarized light is formed from a fundamental wave of s-polarized light by a second harmonic wave forming optical element 9. The fifth harmonic wave of p-polarized light that is subjected to beam shaping by cylindrical lenses 7 and 8, the fundamental wave of s-polarized light, and the second harmonic wave of p-polarized light are combined by a dichroic mirror 10, and are incident on a seventh harmonic wave forming optical element 11.

Abstract: A fifth harmonic wave is formed from a fundamental wave of P polarization via a second harmonic wave forming optical element 3, a third harmonic wave forming optical element 4, and a fifth harmonic wave forming optical element 6, and a second harmonic wave of P polarization is formed from a fundamental wave of P polarization via a second harmonic wave forming optical element 9. A fundamental wave of S polarization is combined with the second harmonic wave of P polarization described above by a dichroic mirror 13; furthermore, the fifth harmonic wave of P polarization, the fundamental wave of S polarization described above and the second harmonic wave of P polarization are combined by a dichroic mirror 10, and are incident on a seventh harmonic wave forming optical element 11.

Abstract: The present invention relates to an optical fiber for amplification, an optical amplifying apparatus, and so on, having a structure for enabling increase of power of output light, suppression of occurrence of nonlinear optical phenomena, and compact storage all together. The optical amplifying apparatus comprises an optical fiber for amplification amplifying input light inputted together with pumping light from a pumping light source. The optical fiber for amplification comprises a core region doped with a rare-earth element, and a cladding region provided on an outer periphery of the core region and having a refractive index lower than that of the core region. The core region has an outer diameter of 10 ?m or more but 30 ?m or less, and has a relative refractive index difference of 0.5% or more but 2.0% or less with respect to the cladding region. The cladding region has an outer diameter of 75 ?m or more but 200 ?m or less.

Abstract: In nonlinear optical crystal 183D, each step of wavelength conversion can be performed using another fundamental wave that is output from light output unit 1612, without using the fundamental wave whose output level has been attenuated after going through wavelength conversion for several steps (wavelength conversion in nonlinear optical crystals 183A to 183C). Therefore, the wavelength conversion efficiency improves and the peak power of optical amplifiers 1611 and 1612 can be suppressed, which allows the wavelength of lights that are output from optical amplifiers 1611 and 1612 to be further narrowed.

Abstract: An ultraviolet light source (1) comprises a laser light source (10) for generating a signal light in the infrared region, a optical amplifier (20) which comprises fiber optical amplifiers (21, 22) and amplifies the signal light generated by the laser light source (10), and a wavelength converting optical system (30) which coverts the signal light amplified by the light amplifier (20) into an ultraviolet light and outputs the converted light. The ultraviolet light source (1) uses a single-mode fiber laser (26) as an excitation light source for at least the fiber optical amplifier (22) at one stage of the optical amplifier (20).