Abstract: A spectral interference height detecting apparatus includes a chuck table for holding a workpiece thereon and a height detecting unit for detecting the height of an upper surface of the workpiece held on the chuck table. The height detecting unit includes a light source for emitting light in a predetermined wavelength band into a first optical path, a condenser disposed in the first optical path for converging light onto the workpiece held on the chuck table, a beam splitter disposed between the light source and the condenser for splitting the light in the first optical path into a second optical path, a mirror disposed in the second optical path to form a basic optical path length, for reflecting light into the second optical path and returning light through the beam splitter to the first optical path.

Abstract: A testing system for testing a workpiece for a characteristic by irradiating microwaves to the workpiece and also irradiating a laser beam at an irradiation position of the microwaves, receiving microwaves reflected at the irradiation position where the workpiece has a reflectivity increased by carriers generated through photoexcitation, and measuring a lifetime of the carriers. The testing system includes a chuck table that holds the workpiece, a microwave irradiation unit that irradiates the microwaves to the workpiece held on the chuck table, a microwave reception unit that receives microwaves reflected by the workpiece, and a laser beam irradiation unit that irradiates the laser beam onto the irradiation position to which the microwaves have been irradiated.

Abstract: Disclosed herein is a laser processing apparatus including first and second laser mechanisms, a laser oscillator for oscillating an original laser beam, an optical system for branching the original laser beam into first and second laser beams, and first and second operation panels for respectively setting first and second processing conditions for the first and second laser mechanisms. The first and second laser mechanisms include first and second chuck tables for holding first and second workpieces, first and second X moving units for moving the first and second chuck tables in an X direction, first and second Y moving units for moving the first and second chuck tables in a Y direction perpendicular to the X direction, and first and second focusing units for focusing the first and second laser beams to the first and second workpieces held on the first and second chuck tables, respectively.

Abstract: A laser processing apparatus includes a controller having (a) a section for storing the Y coordinate of a characteristic point having a predetermined positional relation to each division line formed on a wafer as a reference value with respect to a reference position where the focal point of a laser beam coincides with a predetermined position on each division line, (b) a section for detecting the amount of deviation of the Y coordinate of the characteristic point after indexing each division line of the wafer in the Y direction by the operation of a Y moving unit, from the Y coordinate stored as the reference value, and (c) a section for determining whether or not the amount of deviation detected is greater than an allowable value.

Abstract: A reflectance detection method in which a workpiece is irradiated with a laser beam and reflectance is detected, irradiating, with a light amount H0, the workpiece with a laser beam with a first wavelength X1 shorter than a detection-target wavelength X and detecting a light amount H1 of reflected return light, irradiating the workpiece with a laser beam with a second wavelength X2 longer than the detection-target wavelength X with the light amount H0 and detecting a light amount H2 of reflected return light, and employing H calculated based on an expression shown below as the light amount of return light obtained when the workpiece is irradiated with the detection-target wavelength X and calculating reflectance obtained when the workpiece is irradiated with the detection-target wavelength X based on H/H0.

Abstract: A spectral interference height detecting apparatus includes a chuck table for holding a workpiece thereon and a height detecting unit for detecting the height of an upper surface of the workpiece held on the chuck table. The height detecting unit includes a light source for emitting light in a predetermined wavelength band into a first optical path, a condenser disposed in the first optical path for converging light onto the workpiece held on the chuck table, a beam splitter disposed between the light source and the condenser for splitting the light in the first optical path into a second optical path, a mirror disposed in the second optical path to form a basic optical path length, for reflecting light into the second optical path and returning light through the beam splitter to the first optical path.

Abstract: A reflectance detection method in which a workpiece is irradiated with a laser beam and reflectance is detected, irradiating, with a light amount H0, the workpiece with a laser beam with a first wavelength X1 shorter than a detection-target wavelength X and detecting a light amount H1 of reflected return light, irradiating the workpiece with a laser beam with a second wavelength X2 longer than the detection-target wavelength X with the light amount H0 and detecting a light amount H2 of reflected return light, and employing H calculated based on an expression shown below as the light amount of return light obtained when the workpiece is irradiated with the detection-target wavelength X and calculating reflectance obtained when the workpiece is irradiated with the detection-target wavelength X based on H/H0.

Abstract: Disclosed herein is a laser processing apparatus including a controller. The controller includes a coordinate storing section for storing the Y coordinate of a characteristic point having a predetermined positional relation to each division line formed on a wafer as a reference value with respect to a reference position where the focal point of a laser beam to be focused by a focusing unit coincides with a predetermined position on each division line in a Y direction as an indexing direction, a deviation detecting section for detecting the amount of deviation of the Y coordinate of the characteristic point imaged by an imaging unit after indexing each division line of the wafer in the Y direction by the operation of a Y moving unit, from the Y coordinate stored as the reference value in the coordinate storing section, and a determining section for determining whether or not the amount of deviation detected by the deviation detecting section is greater than an allowable value.

Abstract: A laser processing apparatus includes a beam splitting unit disposed between a pulsed laser beam oscillating unit and a condenser. The beam splitting unit includes a half-wave plate that rotates the plane of polarization of a pulsed laser beam, a birefringent lens that splits the pulsed laser beam that has passed through the half-wave plate into ordinary light and extraordinary light, the birefringent lens being formed by joining two kinds of crystalline bodies to each other across a curved plane of a concave surface and a convex surface, and a splitting angle adjusting unit that moves the birefringent lens in a direction orthogonal to the pulsed laser beam that has passed through the half-wave plate to change the angle of incidence with respect to the curved plane and adjust a beam splitting angle.

Abstract: A laser processing apparatus includes a first chuck table for holding a first workpiece, moving units for moving the first chuck table in X and Y directions, and a first focusing unit for focusing a first laser beam to the first workpiece. A second chuck table holds a second workpiece. Other moving units move the second chuck table in the X direction and Y directions, and a second focusing unit focuses a second laser beam to the second workpiece. A laser oscillator produces an original laser beam, and an optical system branches the original laser beam into the first laser beam and the second laser beam, and leads the first and second laser beams to the first and second focusing units, respectively.

Abstract: Disclosed herein is a laser processing apparatus including first and second laser mechanisms, a laser oscillator for oscillating an original laser beam, an optical system for branching the original laser beam into first and second laser beams, and first and second operation panels for respectively setting first and second processing conditions for the first and second laser mechanisms. The first and second laser mechanisms include first and second chuck tables for holding first and second workpieces, first and second X moving units for moving the first and second chuck tables in an X direction, first and second Y moving units for moving the first and second chuck tables in a Y direction perpendicular to the X direction, and first and second focusing units for focusing the first and second laser beams to the first and second workpieces held on the first and second chuck tables, respectively.

Abstract: A laser machining apparatus that includes an interferometric height position detection unit, a condensing point position adjustment unit, and a confocal optical height position detection unit. A controller of the laser machining apparatus specifies, as a correction value, the difference between the two height positions of the upper face of the workpiece, one detected by the confocal optical height position detection unit and the other detected by the interferometric height position detection unit. The controller controls the condensing point position adjustment unit based on the height position obtained by correcting the height position of the upper face of the workpiece detected by the interferometric height position detection unit using the correction value.

Abstract: A laser processing apparatus includes a beam splitting unit disposed between a pulsed laser beam oscillating unit and a condenser. The beam splitting unit includes a half-wave plate that rotates the plane of polarization of a pulsed laser beam, a birefringent lens that splits the pulsed laser beam that has passed through the half-wave plate into ordinary light and extraordinary light, the birefringent lens being formed by joining two kinds of crystalline bodies to each other across a curved plane of a concave surface and a convex surface, and a splitting angle adjusting unit that moves the birefringent lens in a direction orthogonal to the pulsed laser beam that has passed through the half-wave plate to change the angle of incidence with respect to the curved plane and adjust a beam splitting angle.

Abstract: A laser machining apparatus that includes an interferometric height position detection unit, a condensing point position adjustment unit, and a confocal optical height position detection unit. A controller of the laser machining apparatus specifies, as a correction value, the difference between the two height positions of the upper face of the workpiece, one detected by the confocal optical height position detection unit and the other detected by the interferometric height position detection unit. The controller controls the condensing point position adjustment unit based on the height position obtained by correcting the height position of the upper face of the workpiece detected by the interferometric height position detection unit using the correction value.

Abstract: A laser beam having an annular spot shape with which a workpiece is irradiated is reflected on an upper surface and a lower surface of the workpiece. The reflected light having the annular spot shape which is reflected on the lower surface of the workpiece is intercepted by a pinhole mask, whereas the reflected light having the annular spot shape which is reflected on the upper surface of the workpiece is permitted to pass through the pinhole mask, and the intensity of light received is detected based on the latter reflected light. Therefore, the height position of the upper surface of a workpiece can be detected even where the workpiece is transmissive to visible rays. In this case, with regard to the reflected light having the annular spot shape which is reflected on the upper surface of the workpiece, the intensity of the light after diffusion by a laser beam diffusing unit is detected by a photodetector having a detecting surface with a predetermined area.

Abstract: A laser processing apparatus including a detecting unit. The detecting unit includes a white light source for emitting white light, a focusing lens for focusing the white light to the workpiece, a first optical fiber for guiding the white light emitted from the white light source to the focusing lens, a detector for detecting the intensity of reflected light from the workpiece, and a second optical fiber for guiding the reflected light to the detector. Accordingly, the white light to be focused to the workpiece can be easily handled and only a wavelength component focused on the workpiece can be stably propagated.

Abstract: A laser processing apparatus including a height detecting device for detecting the height of a workpiece held on a chuck table. The height detecting device includes an annular spot forming unit for forming the spot shape of a detecting laser beam into an annular spot shape, a pinhole mask for passing the reflected light reflected on the upper surface of the workpiece held on the chuck table, but blocking the reflected light reflected on the lower surface of the workpiece, and a reflected light analyzing unit for analyzing the reflected light passed through the pinhole mask and transmitting the result of analyzation to a control unit. The laser processing apparatus further includes a focusing unit having an objective lens for focusing a processing laser beam having a circular spot shape and the detecting laser beam having the annular spot shape and a window lens for focusing the detecting laser beam focused by the objective lens without focusing the processing laser beam.

Abstract: A device for detecting the edges of a workpiece held on the chuck table of a processing machine, having a beam oscillation means for oscillating a detection beam, an objective lens for focusing the detection beam oscillated from the beam oscillation means, and a reflected light detection means for detecting the reflected light of the detection beam applied through the objective lens, wherein the beam oscillation means oscillates the detection beam in such a manner that the optical axis of the detection beam becomes parallel to the center axis of the objective lens at a position offset from the center axis; and the reflected light detection means detects the edge of the workpiece based on a positional difference between reflected light obtained when the detection beam applied through the objective lens is reflected on an area where the workpiece is not existent and refracted by the objective lens and reflected light obtained when the detection beam is reflected on the workpiece and refracted by the objective l

Abstract: A laser beam machining apparatus including a beam oscillator; a beam adjusting unit disposed between the beam oscillator and a condenser lens and by which the beam diameter and the divergence angle of the beam oscillated from the beam oscillator are adjusted; and a beam diameter and divergence angle detecting unit for detecting the beam diameter and the divergence angle of the beam having passed through the beam adjusting unit. The apparatus further includes a control unit which computes the beam diameter and the divergence angle of the beam, based on detection signals from the beam diameter and divergence angle detecting unit, and which controls the beam adjusting unit, based on the computed beam diameter and divergence angle of the beam and the beam diameter and the divergence angle of the laser beam incident on the beam diameter and divergence angle detecting unit.

Abstract: A polarizing device for converting a circularly polarized light beam into a radial polarized light beam, wherein the circularly polarized light beam is obtained by passing a linearly polarized light beam oscillated from a laser oscillator through a quarter-wave plate. The polarizing device includes an axicon lens having a conical surface and a dielectric film formed on the conical surface of the axicon lens.