Laser beam machining method and apparatus
AssigneeMoritax Corporation
InventorsKazuyoshi Ohta, Naoshige Sasano
Life of this patent
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Abstract
Disclosed is a laser beam machining method and apparatus for irradiating a work with a laser beam, to melt-evaporate the irradiated region of the work at the irradiation spot. According to the invention, a work such as an optical fiber can be machined into a complicated form within a short period of time without accurately controlling the laser beam irradiation position while inhibiting the decline of machining accuracy due to thermal effect, by using a mask having a light-transmitting section that is predetermined times as large as the laser beam machining spot corresponding to the form of the portion undergoing melt-evaporation of the work.
Claims24
A laser beam machining method, in which a work is irradiated with a laser beam to melt-evaporate the portion irradiated with the laser beam for machining the work, comprising:
- a mask having a light-transmitting section that is predetermined times as large as the laser beam machining spot corresponding to the form of the portion undergoing melt-evaporation of the work, is disposed between a laser beam source and the work, and
- the laser beam transmitted from a laser beam source through a beam-shaping optical system is irradiated to said mask in a range larger than said light-transmitting section of the mask, and the real image of the light-transmitting section formed by the transmitted light is reduced to the size of said machining spot by means of a reduced image-forming optical system, to form the reduced image on the work, and rotating the work around an axis perpendicular to an axis of the laser beam while the work is being machined by melt evaporation.
A laser beam machining methods in which a work is irradiated with a laser beam to melt-evaporate the portion irradiated with the laser beam for machining the work, characterized in that
- a mask with a quadrilateral light-transmitting section that is predetermined times as large as a quadrilateral machining spot is disposed between a laser beam source and the work, and
- the laser beam transmitted from the easer beam source through a beam-shaping optical system is irradiated to said mask in a range larger than said light-transmitting section, and the real image of the light-transmitting section formed by the transmitted light is reduced to the size of said machining spot by means of a reduced image-forming optical system, to form the reduced image on the work, for machining.
A laser beam machining apparatus, for melt evaporating a portion of work irradiated, comprising:
- a mask is disposed between a laser beam source and a work held by a holding means;
- a light-transmitting section that is predetermined times as large as a laser beam machining spot corresponding to the form of the portion of the work undergoing melt-evaporation;
- disposed between the laser beam source and said mask is a shaping optical system for irradiating said mask with a laser beam in a range larger than said light-transmitting section;
- and
- a reduced image-forming optical system for reducing a real image of the light-transmitting section formed by the laser beam passing through the light-transmitting section of the mask to the size of said machining spot, and for forming the reduced image on the work, the work holding means being rotatable for rotating the work around an axial direction of the work.
A laser beam machining method, in which a work is irradiated with a laser beam to melt-evaporate the portion irradiated with the laser beam for machining the work, wherein:
- a mask having a light-transmitting section that is predetermined times as large as the laser beam machining spot corresponding to the form of the portion undergoing melt-evaporation of the work, is disposed between a laser beam source and the work, and
- the laser beam transmitted from a laser beam source through a beam-shaping optical system is irradiated to said mask in an area larger than said light-transmitting section of the mask, and a real image of the light-transmitting section formed by the transmitted light is reduced to the size of said machining spot by means of a reduced image-forming optical system, to form the reduced image on the work, and the real image-forming position is relatively moved along the laser beam irradiation axis while the work is machined.
In a method of shaping a tip of an optical fiber into a desired form using a laser to melt evaporate a portion of the fiber tip, the improvement comprising:
- directing a laser beam from a laser source through a beam-shaping optical system, a mask, a reduced image-forming optical system onto a tip of an optical fiber, in that order, said beam-shaping optical system comprising a magnifying collimator lens system, said mask having a light transmitting aperture therein, the laser beam from the beam-shaping optical system irradiating the mask being larger than the light transmitting aperture in the mask, the light transmitting aperture in the mask being a predetermined times as large as a spot on the tip of the optical fiber to be melt evaporated, the laser beam passing through the aperture in the mask is then reduced by the reduced image forming optical system to form a real image of the aperture in the mask on the tip of the optical fiber, thereby melt evaporating a portion of the fiber tip corresponding to the light transmitting aperture in the mask,
- the reduced image forming system having a focal distance f, and the tip of the optical fiber to be shaped being spaced from the reduced image forming system a distance greater than f while being melt evaporated in the shaping operation.
Dependencies are inferred from the claim text.