Abstract: There is provided a laser processing method using a laser processing apparatus including a laser beam source for outputting a laser beam including a plurality of wavelength components, a collimating lens for receiving the laser beam, and a focusing lens for receiving the laser beam collimated by the collimating lens, the laser processing method including the step of: irradiating a material to be processed with the laser beam focused by the focusing lens in the laser processing apparatus. In the step of irradiating the material to be processed with the laser beam, positions of the collimating lens and the focusing lens are adjusted, and a wavefront shape of the laser beam received by the focusing lens is adjusted, thereby adjusting a size of a focusing area constituted by a plurality of focuses corresponding to the plurality of wavelength components of the laser beam focused by the focusing lens.

Abstract: The present invention relates to a laser light source capable of suppressing variation in propagation state of randomly-polarized laser light. In the laser light source, an isolator including a Faraday rotation crystal having a positive thermooptic constant, and a nonlinear optical crystal having a negative thermooptic constant are arranged in order along a traveling direction of laser light. The nonlinear optical crystal is arranged in a state off normal incidence of incident light so that a propagation axis of light propagating in the crystal is parallel to an optic axis of the crystal.

Abstract: The present invention relates to a laser light source capable of suppressing variation in propagation state of randomly-polarized laser light. In the laser light source, an isolator including a Faraday rotation crystal having a positive thermooptic constant, and a nonlinear optical crystal having a negative thermooptic constant are arranged in order along a traveling direction of laser light. The nonlinear optical crystal is arranged in a state off normal incidence of incident light so that a propagation axis of light propagating in the crystal is parallel to an optic axis of the crystal.

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 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: 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 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 pulse light source comprises a semiconductor laser outputting pulse light, an optical filter, and an optical amplifier. The optical filter outputs a chirping component of the inputted pulse light, by adjusting a relative position of a transmission spectrum of the optical filter with respect to an output spectrum of the seed 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 a laser light source and others for decreasing wavelength-by-wavelength differences of focal positions of focused components in collimating and then focusing polychromatic light with a wide spectrum width. The laser light source includes a collimator device, in which relative positions of emergence of a laser beam emitted from a polychromatic light source and a collimating lens composed of an achromatic lens can be adjusted at a 10 ?m level or less.

Abstract: The present invention relates to a laser apparatus capable of supplying laser beams from each of plural beam emitting ends constituting laser beam output ports, and realizes the overall low power consumption and low non-linearization. The laser apparatus comprises a seed light source, beam emitting ends, an intermediate optical amplifier, an optical branching device, and final-stage optical amplifiers. The number of beam emitting ends is greater than the number of seed light sources, and the final-stage optical amplifiers and the beam emitting ends correspond to each other one-on-one. The optical branching device includes an input port associated to the seed light source and plural output ports associated to the respective beam emitting ends so as to constitute a part of the light paths between the seed light source and the beam emitting ends.

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 pulse light source comprises a semiconductor laser outputting pulse light, an optical filter, and an optical amplifier. The optical filter outputs a chirping component of the inputted pulse light, by adjusting a relative position of a transmission spectrum of the optical filter with respect to an output spectrum of the seed light source.

Abstract: The present invention relates to a laser processing method and the like which use no wavelength conversion technique by nonlinear optical crystals when selectively removing an insulating layer of a printed board, while employing only one wavelength throughout the entire removal processing. A laser processing apparatus (1), preferably used in the laser processing method, has a MOPA structure and comprises a seed light source (100), a YbDF (110), a bandpass filter (120), a YbDF (130), a bandpass filter (140), a YbDF (150), a YbDF (160), and so forth.

Abstract: The pulse light source comprises a seed light source, a first YbDF, 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 side more than the optical power on the other side between the shorter and longer wavelength sides.

Abstract: The present invention relates to a laser marking method which is capable of changing the grey level of a marking even in the case of a high processing speed. The laser marking method forms a marking pattern on a marking object by irradiating the marking object with pulsed light oscillated from a pulsed light source of a MOPA structure in which a semiconductor laser outputting directly-modulated pulsed light is used as a seed light source. At this time, the pulse duration of the pulsed light is changed in order to change a gray level of the marking pattern to be formed. In this way, a peak power of the pulsed light is changed by changing the pulse duration, so that it is possible to positively change the gray level of the marking pattern without changing the processing speed.

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 method and the like provided with a structure for enabling realization of both preferable processing of locations not easily reached by laser light and effective inhibition of damage caused to locations easily reached by laser light during laser processing. Radiation optics scan locations irradiated with laser light from a laser light source while radiating laser light onto a plurality of objects arranged on a stage and the periphery thereof from a direction perpendicular to the stage. On the stage reflecting members are respectively arranged adjacent to the plurality of objects. The reflecting members reflect laser light radiated from the radiation optics towards lateral surfaces of the objects. Since laser light reflected by the reflecting members is radiated onto the lateral surfaces of the objects, laser light also reaches the lateral surfaces of the objects not easily reached by laser light without having to increase the intensity of the laser light.

Abstract: The pulse light source comprises a seed light source, a first YbDF, 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 side more than the optical power on the other side between the shorter and longer wavelength sides.

Abstract: The present invention relates to a laser light source and others for decreasing wavelength-by-wavelength differences of focal positions of focused components in collimating and then focusing polychromatic light with a wide spectrum width. The laser light source includes a collimator device, in which relative positions of emergence of a laser beam emitted from a polychromatic light source and a collimating lens composed of an achromatic lens can be adjusted at a 10 ?m level or less.