Abstract: The present invention relates to a MOPA light source capable of obtaining pulse output by wavelength-conversion of pulse light of fundamental light wave using a simple configuration, and suppressing optical output using a simple method when processing is not performed. The fundamental light wave outputted from a seed light source is amplified in an optical amplification fiber. The amplified fundamental light wave is inputted to one end of a passive optical fiber, and propagates in the passive optical fiber. In the passive optical fiber, stimulated Raman scattering occurs upon propagation of the fundamental light wave. The light of fundamental light wave and light of stimulated Raman-scattered components are outputted from the other end of the passive optical fiber. The light outputted from the passive optical fiber is collimated by a lens, and is then inputted to a branching filter.

Abstract: The present invention relates to a laser apparatus having a structure for easily shortening a pulse. In the laser apparatus, as a result of a phase control unit adjusting a modulation period of an external modulator and an output period of pulsed light of a seed light source, it is possible to generate pulsed light which is outputted only during a period when the modulation period and the output period overlap each other.

Abstract: The present invention relates to a laser apparatus having a structure for facilitating the change of a transparent wavelength band of a bandpass filter in accordance with a central wavelength of pulsed light. In the laser apparatus, the transparent wavelength band of light to be transmitted through a BPF is changed according to the central wavelength of the pulsed light when the pulse width of the pulsed light outputted from a seed light source is changed.

Abstract: The present invention relates to a laser apparatus having a structure for removing a skirt portion contained in pulsed light, and a laser processing method using the laser apparatus. The laser apparatus comprises a MOPA fiber laser light source which outputs pulsed light having a skirt portion with a light intensity lower than a predetermined value, and a saturable absorber which removes a skirt portion from the pulsed light outputted from the MOPA fiber laser light source.

Abstract: The present invention relates to a method of enabling generation of pulsed lights each having a narrow pulse width and high effective pulse energys. A pulse light source has a MOPA structure, and comprises a single semiconductor laser, a bandpass filter and an optical fiber amplifier. The single semiconductor laser outputs two or more pulsed lights separated by a predetermined interval, for each period given according to a predetermined repetition frequency. The bandpass filter attenuates one of the shorter wavelength side and the longer wavelength side, in the wavelength band of input pulsed lights.

Abstract: The present invention relates to a light source apparatus. The light source apparatus has an MOPA configuration and comprises a seed light source, a pulse generator, an intermediate optical amplifier, a final stage optical amplifier, a delivery optical fiber, and a light output terminal. The delivery optical fiber is a PBG fiber having a photonic bandgap (PBG) structure in a core-surrounding portion located around the core. Light with a wavelength in a high loss band of the PBG fiber is inputted into the PBG fiber.

Abstract: The present invention relates to a light source control method capable of decreasing the dependence of a pulse width (FWHM) of an output pulsed light on a repetition frequency. A pulsed light source has an MOPA structure, and has a seed light source and an optical fiber amplifier. The seed light source includes a semiconductor laser which is directly modulated and outputs a pulsed light. By adjusting a temperature of the seed light source and a pumping light power of the optical fiber amplifier, a predetermined full width half maximum of a pulse at a predetermined repetition frequency is implemented for the pulsed light outputted from the optical fiber amplifier.

Abstract: The invention relates to a pulsed light source capable of effectively utilizing optical power and selecting the pulse width of output pulsed light. A pulsed light source has a MOPA structure, and comprises a seed light source and an optical fiber amplifier. The seed light source includes a semiconductor laser outputting pulsed light. In the optical fiber amplifier, an optical filter branches pulsed light amplified by a YbDF into a first wavelength component including the peak wavelength and the remaining second wavelength component. An optical switch outputs one of the pulsed light of the first wavelength component and the pulsed light of the second wavelength component which are inputted. Another YbDF amplifies the pulsed light outputted from the optical switch.

Abstract: The present invention relates to a light source apparatus or the like provided with a structure that can block reflected return light also when an emitting end side of an optical isolator is a space. The light source apparatus comprises a light source section, a guide section, and an optical module. The optical module includes a collimator, an optical isolator, and an oblique-beam blocking section. The collimator outputs collimated light with a predetermined beam diameter as a forward propagating beam. The optical isolator is a polarization-independent optical isolator that introduces the collimated light from a first end and outputs this collimated light from a second end.

Abstract: The present invention relates to a laser processing method and the like having a structure for making it possible to process an object to be processed in various ways while accurately adjusting the installation state of the object. The method irradiates the object with plural adjustment laser light beams that are set in a specific positional relationship against a converging point of processing laser light beam, and adjusts the state of installation of the object while monitoring irradiation areas of the adjustment laser light beams on the surface of the object. Each irradiation directions of adjustment laser light beams is different from that of the processing laser light beam. By reflecting the irradiation condition of the adjustment laser light beam and monitored information of the irradiation areas in positional adjustment of the object, the installation state of the object can be adjusted in accordance with various kinds of processing.

Abstract: The present invention relates to a pulse light source which has a MOPA structure using a directly-modulated semiconductor laser as a seed light source, and is easily capable of outputting pulse light with a pulse width of a sub-nanosecond. The pulse light source comprises a seed light source, a first YbDF (Yb-Doped Fiber), a band-pass filter, a second YbDF, and a third YbDF, and has the MOPA structure. The band-pass filter inputs pulse light which is outputted from the seed light source and amplified by the first stage YbDF, and outputs, while separating a wavelength band of the inputted pulse light into a shorter wavelength side and a longer wavelength side with reference to a peak wavelength of the inputted pulse light, the attenuated pulse light after attenuating the optical power on one more than that on the other of the shorter wavelength side and the longer wavelength side.

Abstract: The present invention relates to a laser light source having a structure for effectively suppressing generation of an optical surge upon a restart after suspension of output of pulsed light. The laser light source comprises a first light source outputting light with a first wavelength as pulsed light, a second light source outputting light with a second wavelength different from the first wavelength, an optical amplification fiber as an optical amplifier amplifying the pulsed light outputted from the first light source and the light outputted from the second light source, and a control unit controlling the output of the light from the second light source in accordance with the light output from the first light source. The first light source has an ON state in which repetitive output of the pulsed light on a fixed cycle starts and continues, and an OFF state in which the output of the pulsed light is suspended during a duration of not less than the fixed cycle.

Abstract: There is obtained a laser processing method by which an excellent shape of a cut surface can be achieved and an increase in cost can be suppressed. A laser processing method includes the steps of: preparing a material to be processed; and forming a modified area in the material to be processed, by irradiating the material to be processed with laser beam. In the aforementioned step, pulsed laser beam having a continuous spectrum is focused with a lens, thereby forming a focusing line constituted by a plurality of focuses that are obtained by predetermined bands forming the continuous spectrum of the laser beam, and the material to be processed is irradiated with the laser beam such that at least a part of the focusing line is located on a surface of the material to be processed, thereby forming the modified area on an axis of the focusing line.

Abstract: The present invention relates to a laser processing apparatus and the like having a structure for implementing at the same time both an efficient laser processing in the place where a laser beam is difficult to reach and a laser processing without damages in the place where the laser beam is easy to reach. This laser processing apparatus comprises a laser light source, an irradiation optical system applying a laser beam to an object while scanning the laser beam, a photo-detector detecting the laser beam applied from the irradiation optical system, and a control section of making switching between a continuous oscillation and a pulse oscillation of the laser beam at the laser light source.

Abstract: The present invention relates to a method of processing a metal thin film formed on a transparent substrate by radiating pulsed light onto the metal thin film, and having the steps of repeatedly outputting the pulsed light by directly modulating a semiconductor laser of the seed light source in accordance with electric signals, amplifying the pulsed light using an optical amplifier including an optical amplification medium, controlling the full width at half maximum of the pulsed light that is amplified and outputted by the optical amplifier to be 0.5 ns or less, and removing the metal thin film by radiating the pulsed light thus having the controlled full width at half maximum onto the metal thin film through the transparent substrate.

Abstract: The present invention relates to an optical fiber amplifying module equipped with a structure for stably attaining a high gain even when amplifying light having a low duty cycle. The optical fiber amplifying module comprises at least three amplification optical fibers successively arranged from an input connector to an output collimator. A bandpass filter is arranged between the first- and second-stage amplification optical fibers. Control means having a structure constituted by optically passive components alone or a feedback structure functions so as to render an upper limit to a gain for input light in the first-stage amplification optical fiber, thereby preventing the deterioration in performances such as destruction of the bandpass filter from occurring in optical components positioned on the upstream side of the final-stage amplification optical fiber.

Abstract: The present invention relates to a method and apparatus having a structure that enables laser processing of an object even when the object has a surface formed with irregularities. The laser processing method irradiates objects, each having a cylindrical form extending in a first direction, with laser light. Here, the objects are arranged on a first plane along a second direction orthogonal to the first direction. The arranged objects are irradiated with first and second laser light beams in irradiation directions different from each other to the first plane. At least during when the first and second irradiation light beams are respectively emitted, irradiation positions of the first and second laser light beams to the first plane are relatively moved.

Abstract: The present invention relates to an optical fiber amplifying module equipped with a structure for stably attaining a high gain even when amplifying light having a low duty cycle. The optical fiber amplifying module comprises at least three amplification optical fibers successively arranged from an input connector to an output collimator. A bandpass filter is arranged between the first- and second-stage amplification optical fibers. Control means having a structure constituted by optically passive components alone or a feedback structure functions so as to render an upper limit to a gain for input light in the first-stage amplification optical fiber, thereby preventing the deterioration in performances such as destruction of the bandpass filter from occurring in optical components positioned on the upstream side of the final-stage amplification optical fiber.

Abstract: The present invention relates to a laser processing apparatus and the like having a structure for implementing at the same time both an efficient laser processing in the place where a laser beam is difficult to reach and a laser processing without damages in the place where the laser beam is easy to reach. This laser processing apparatus comprises a laser light source, an irradiation optical system applying a laser beam to an object while scanning the laser beam, a photo-detector detecting the laser beam applied from the irradiation optical system, and a control section of making switching between a continuous oscillation and a pulse oscillation of the laser beam at the laser light source.

Abstract: The present invention relates to a method of measuring backward light, which is constructed for checking, prior to laser processing, backward light that propagates backward through an isolator included in a laser processing apparatus. The present invention also relates to a laser processing method and the like. A laser processing apparatus has an optical head provided with a laser light source part, light guide, and isolator. The optical head has an emitting optical system, irradiation optical system, and light collecting optical system. The method of measuring backward light uses a photodetector to detect, from reference light introduced from a measurement light source into the optical head, the power of an optical component that has passed through the isolator, while changing the position of the measurement light source.