Abstract: A method of cutting an object to be processed comprises the steps of irradiating an object to be processed with a laser light which is an elliptically-polarized light having an ellipticity other than 1 such that a direction of polarization of the laser light intersects a line to cut the object and a thickness direction of the object, while locating a converging point of the laser light within the object, so as to form a modified region within the object along the line and generate a fracture from the modified region in the thickness direction of the object, and causing the fracture to reach front and rear faces of the object so as to cut the object along the line.

Abstract: A method of cutting an object to be processed comprises the steps of irradiating an object to be processed with a laser light which is an elliptically-polarized light having an ellipticity other than 1 such that a direction of polarization of the laser light intersects a line to cut the object and a thickness direction of the object, while locating a converging point of the laser light within the object, so as to form a modified region within the object along the line and generate a fracture from the modified region in the thickness direction of the object, and causing the fracture to reach front and rear faces of the object so as to cut the object along the line.

Abstract: A plurality of modified parts are formed at a first formation pitch for a line arranged along the M-plane of a single-crystal sapphire substrate to construct a modified region and cause a fracture occurring from the modified region to reach a principal surface of the single-crystal sapphire substrate. A plurality of modified parts are formed at a second formation pitch narrower than the first formation pitch for a line arranged along the A-plane of the single-crystal sapphire substrate to construct a modified region and cause a fracture occurring from the modified region to reach the principal surface of the single-crystal sapphire substrate. Along the lines, a knife edge is pressed against a wafer from the side of the single-crystal sapphire substrate opposite from the principal surface of the single-crystal sapphire substrate where the fractures have reached, to cut the wafer along the lines.

Abstract: A plurality of modified parts are formed at a first formation pitch for a line arranged along the M-plane of a single-crystal sapphire substrate to construct a modified region and cause a fracture occurring from the modified region to reach a principal surface of the single-crystal sapphire substrate. A plurality of modified parts are formed at a second formation pitch narrower than the first formation pitch for a line arranged along the A-plane of the single-crystal sapphire substrate to construct a modified region and cause a fracture occurring from the modified region to reach the principal surface of the single-crystal sapphire substrate. Along the lines, a knife edge is pressed against a wafer from the side of the single-crystal sapphire substrate opposite from the principal surface of the single-crystal sapphire substrate where the fractures have reached, to cut the wafer along the lines.

Abstract: A method of cutting an object to be processed comprises the steps of irradiating an object to be processed with a laser light which is an elliptically-polarized light having an ellipticity other than 1 such that a direction of polarization of the laser light intersects a line to cut the object and a thickness direction of the object, while locating a converging point of the laser light within the object, so as to form a modified region within the object along the line and generate a fracture from the modified region in the thickness direction of the object, and causing the fracture to reach front and rear faces of the object so as to cut the object along the line.

Abstract: A method of cutting an object to be processed comprises the steps of irradiating an object to be processed with a laser light which is an elliptically-polarized light having an ellipticity other than 1 such that a direction of polarization of the laser light intersects a line to cut the object and a thickness direction of the object, while locating a converging point of the laser light within the object, so as to form a modified region within the object along the line and generate a fracture from the modified region in the thickness direction of the object, and causing the fracture to reach front and rear faces of the object so as to cut the object along the line.

Abstract: It is possible to reduce the size of a magneto-optical device, increase the speed of optical control, simplify power supply structure and its control, and maintain a Faraday rotation angle in an arbitrary state even after shut-off of the excitation current. The magneto-optical device includes a magnetic yoke (10) made of a high-permeability magnetic material, the magnetic yoke including a tabular portion (16) and four pillar portions (18) protruding from one side of the tabular portion (16), a coil (12) wound on each of the pillar portions, and a magneto-optical element (14) arranged in an open-magnetic-circuit region surrounded by the end portions of the four pillar portions. A magnetic field obtained by a coil is applied to the magneto-optical element.

Abstract: It is possible to reduce the size of a magneto-optical device, increase the speed of optical control, simplify power supply structure and its control, and maintain a Faraday rotation angle in an arbitrary state even after shut-off of the excitation current. The magneto-optical device includes a magnetic yoke (10) made of a high-permeability magnetic material, the magnetic yoke including a tabular portion (16) and four pillar portions (18) protruding from one side of the tabular portion (16), a coil (12) wound on each of the pillar portions, and a magneto-optical element (14) arranged in an open-magnetic-circuit region surrounded by the end portions of the four pillar portions. A magnetic field obtained by a coil is applied to the magneto-optical element.

Abstract: A polarized-light separating/combining element is obtained which can suppress deviation in a direction of rays (angular error), reduce beam coupling loss and improve extinction ratio. Size reduction and loss lowering is achieved for an optical device (optical circulator or optical switch), to enable manufacture at a low cost and with ease. A polarized-light separating/combining element has a transparent member having flat surfaces parallel with each other on which both parallel surfaces, polarized-light separating/combining films are formed respectively, wherein both polarized-light separating/combining films are faced to air. By using the polarized-light separating/combining element, various kinds of optical devices (optical circulators or optical switches) can be formed. Particularly, it is effective for realizing a low crosstalk characteristic in a matrix optical switch.

Abstract: A polarized-light separating/combining element is obtained which can suppress deviation in a direction of rays (angular error), reduce beam coupling loss and improve extinction ratio. Size reduction and loss lowering is achieved for an optical device (optical circulator or optical switch), to enable manufacture at low cost and with easiness. In the present invention, a polarized-light separating/combining element 10 has a transparent member 12 having flat surfaces parallel with each other on which parallel both surfaces, polarized-light separating/combining films 14 are formed respectively, wherein the both polarized-light separating/combining films are faced to air. By using the polarized-light separating/combining element, various kinds of optical devices (optical circulators or optical switches) are structured. Particularly, it is effective for realizing a low crosstalk characteristic in a matrix optical switch.

Abstract: Provided are an optical rotator which is capable of switch-operating at high speed, small in size and low in price, an optical switch readily compatible with an array structure and matrix form, and a variable optical attenuator readily compatible with an array structure. In the present invention, an optical rotator 14 comprises a lamination coil 10a, . . . , 10c having a through-hole and a Faraday element 11 arranged in the through-hole or a vicinity thereof, whereby a magnetic field caused by the coil is applied to the Faraday element. The Faraday element is arranged such that light passes vertically to the main surface thereof in which direction a magnetic field can be applied. A magnetism-holding member of a high magnetic permeable material is preferably arranged at least in a part of an outer periphery of the coil. In case the Faraday element uses a magnetic garnet crystal having a residual magnetization, obtained is an optical rotator having a self-sustaining function.