Abstract: A system for shaping an optical fiber with various geometries while minimizing unwanted artifacts in the core of the optical fiber. The system facilitates control of sag in the region of the core that is exposed to a beam of optical energy. The sag is reduced, if not eliminated, by maintaining the cross-sectional area of the core that is exposed to the beam at thermal equilibrium.

Abstract: A method and apparatus for securing a workpiece during a polishing operation are described. More particularly, embodiments of the present invention provide a support fixture for securing a workpiece. The support fixture includes a gripping member that is configured to grip a workpiece and configured to release the workpiece. The support fixture also includes a ferrule that is configured to tighten the gripping member around the workpiece and configured to release the gripping member from the workpiece.

Abstract: The cleaning apparatus for electrodes includes a supporting container provided with a replaceable brush body; and a rotation mechanism for the rotation of the supporting container. The brush body accepts the insertion of the electrodes and cleans the tip end thereof by rotation.

Abstract: The present disclosure relates to a device for holding a plurality of fiber optic connectors. The device includes a clamp defining a plurality of ferrule receiving openings, a set plane with openings for the fibers, an alignment surface on which the ferrules rest, and an actuator for moving moveable portions of the clamp. The clamp has a plurality of moveable portions that at least partially define the ferrule receiving openings. The moveable portions are moveable between a rest, biased closed position in which the ferrules are clamped within the ferrule receiving openings, and an open position in which ferrules can be inserted in the ferrule receiving openings.

Abstract: An object of the present invention is to provide an optical connector capable of preventing impairment of PC connections by a hard sleeve during PC connection of optical connectors having a hard sleeve installed in engaging pin holes thereof. The optical connector has a ferrule formed with integrally molded plastic and having engaging pin holes, and a hard sleeve installed in the engaging pin holes and having a hardness that is higher than the plastic of the ferrule. The hard sleeve and the plastic of the ferrule surrounding this hard sleeve are polished so as to be lower than the coupling end surface, and the end of the hard sleeve does not protrude beyond the coupling end surface.

Abstract: Methods of bonding optical components are disclosed. Bonding is achieved without use of adhesives or high temperature fusion. The invention is useful for bonding optical fibers together and for bonding optical fiber arrays to lens arrays.

Abstract: A simple, effective and inexpensive method produces an optical connection on an optical component. A waveguide section, a sleeve for enclosing the waveguide section and an optical component, which has a receptacle for the waveguide section and the sleeve, are provided. The waveguide section is inserted with the first end face into the receptacle of the component and is only cut to length after insertion, while it is mounted on the component. The front end face of the waveguide section is milled away in a centered, spherical concave form.

Abstract: A cleaning apparatus (100) for cleaning an endface (202) of an optical fiber contained within an interface device (200) is provided. The cleaning apparatus includes a housing (110) having an interface portion (116) adapted to be received by the interface device. The cleaning apparatus also includes at least a first nozzle (126) operable to deliver a pressurized gas and a solvent upon the endface to aid in the removal of contaminants on the endface. A method for cleaning an endface of an optical fiber contained within an interface device is also provided. The method comprises the steps of inserting an interface portion within the interface device so as to position a nozzle in proximity to the endface of the interface device. The method further comprises the steps of directing a pressurized gas through the nozzle toward the endface and intermixing a solvent with the pressurized gas.

Abstract: The center of a turntable 30 moves around the central axial line of an autoroation disk 20 along the circular orbit C of a smaller diameter than that of an autorotation disk 20. Thus, the turntable 30 revolves both around a center point O and on its own axis in accordance with an autorotation of the autorotation disk 20. A polishing holder 60 holds a connector of an optical fiber polished by a polishing film 41 arranged on the upper plane of the turntable 30. An optical fiber end face polishing machine provided with a memory 85 for storing a control program which allows a control device 80 to execute predetermined polishing steps, the control device 80 being for controlling an autorotation motor 16 of the turntable 30 and a revolution motor 14 thereof.

Abstract: The method and apparatus of the present invention is capable of precisely determining the orientation of the axis of the guide pin hole defined by a multifiber ferrule. Since the axis of the guide pin hole has a direct relationship to the alignment of the optical fibers, the method and apparatus can also precisely determine the end face angle of the ferrule based upon the axis of the guide pin hole without reference to external features of the ferrule. A measurement pin is initially positioned in a guide pin hole such that a first end of the measurement pin is disposed proximate the end face of the ferrule. The reference plane defined by the first end of the measurement pin is then measured, such as by an interferometer. Based upon the reference plane and the predetermined angle between the reference plane and the axis of the guide pin hole, the method and apparatus can precisely determine the orientation of the axis of the guide pin hole.

Abstract: A ferrule with optical fiber is held to a ferrule holder. The ferrule is made of a material with 0.5˜2 times the wearing speed characteristic in comparison with a quartz glass. The ferrule holder comprises a polishing plate which has an elastic module equivalent to 70˜95 degrees of rubber hardness in a state of adhering a polishing sheet thereon. The ferrule holder is made to be self-supported on a polishing table in a manner such that the end face of the ferrule with optical fiber is in contact with the polishing sheet. The ferrule holder is made to manually move on the polishing table by a predetermined distance in the horizontal direction to slide the end face of the ferrule with optical fiber on the polishing sheet, thereby the end face of the ferrule with optical fiber is polished to a spherical convex surface centered on the optical fiber.

Abstract: A method and device for cleaning at least an end face of an optical device retained within an optical connector using a cleaning fabric, comprises, alone or in combination, a) preventing the cleaning fabric from contacting the connector prior to contacting the end face of the optical device; b) a cleaning nose being made of a nose material having a hardness less than that of a material of the optical device with a flexural modulus greater than 2700 MPa and c) ensuring a constant tension on the fabric as it is circulated.

Abstract: An optical fiber device includes a plurality of optical fibers that are bundled together within an impact mounted ferrule. A preferred impact mounted bundled optical fiber device includes two, three, four, seven, thirteen or nineteen optical fibers. In these devices the optical fibers are fixedly held in place by frictional contact between the optical fibers within the impact mounted ferrule tip. The impact mounted bundled optical ferrule can be utilized in many optical devices including add/drop devices, bifurcation devices, signal combining devices, multiplexer devices, demultiplexer devices, isolator devices, as well as other types of optical signal processing devices.

Abstract: The method and apparatus of the present invention is capable of precisely determining the orientation of the axis of the guide pin hole defined by a multifiber ferrule. Since the axis of the guide pin hole has a direct relationship to the alignment of the optical fibers, the method and apparatus can also precisely determine the end face angle of the ferrule based upon the axis of the guide pin hole without reference to external features of the ferrule. A measurement pin is initially positioned in a guide pin hole such that a first end of the measurement pin is disposed proximate the end face of the ferrule. The reference plane defined by the first end of the measurement pin is then measured, such as by an interferometer. Based upon the reference plane and the predetermined angle between the reference plane and the axis of the guide pin hole, the method and apparatus can precisely determine the orientation of the axis of the guide pin hole.

Abstract: A device for cleaving optical fibers having a housing with an internal chamber, a fiber alignment member removably connected to the housing and a fiber cutting member supported by the housing. The alignment member has an opening sized to receive the ferrule of a fiber optic connector and has a stop proximate to the inward end of an opening to engaged the ferrule distal end. The alignment member is quickly interchangeable with another sized and arranged to handle the ferrule of a different type or size connector. The opening is sized to receive ferrule with an optical fiber to be cleaved, and permits the fiber to extend inward beyond the inward end of the opening and into the housing internal chamber.

Abstract: An end face polishing apparatus has a support member mounted for undergoing rotational movement. A tubular member is mounted on the support member for rotation therewith. The tubular member has a first surface connected to a main surface of the support member and a second surface extending in an axial direction at a first distance from the main surface of the support member. A lapping member is mounted on the support member for rotation therewith. The lapping member has a first surface connected to the main surface of the support member and a second surface extending in the axial direction at a second distance from the main surface of the support member smaller than the first distance.

Abstract: An apparatus is provided for making a collimator for precise alignment of an output optical path emanating from the collimator to obviate the need for adjusting the collimator during assembly to an optical device to compensate for a translational offset and an angular deviation. In an embodiment, the apparatus is capable of determining the translational offset and the angular deviation, and removing a portion of an outer sleeve of the collimator according to the offset and the deviation to form an outer cylindrical surface that is centered about an axis which coincides with the optical path emanating from the collimator, to allow the collimator to be readily fitted to an optical device.

Abstract: A process for field terminating at least one optical fiber in an optical fiber connector plug. The process provides an article for retaining an optical fiber cable. The article comprises a housing having a recess for an optical fiber holder and further includes a pivoting guide plate attached at one end of the housing. A rotatable lid attached to the housing rotates between an open position and a closed position. The article retains the optical fiber cable for cleaving and polishing the end face of an optical fiber when the lid is closed. The guide plate engages a cleaving device for cleaving at least one optical fiber. This is followed by end face polishing, of the optical fiber, and release of the optical fiber cable, the optical fiber holder, and the stripped, cleaved and polished optical fiber from the article.

Abstract: A method and apparatus precisely determines the orientation of the axis of a guide pin hole defined by a multifiber ferrule, and therefrom, precisely determines an end face angle of the ferrule without reference to external features of the ferrule. A measurement pin is positioned in the guide pin hole with a first end disposed proximate the end face of the ferrule. A reference plane defined by the first end of the measurement pin is measured. The orientation of the axis of the guide pin hole is determined based upon the predetermined angle between the axis of the guide pin hole and the reference plane. A plane defined by at least a portion of the end face of the ferrule is then measured. The end face angle is precisely determined based upon the angular difference between the reference plane and the plane defined by the end face of the ferrule.

Abstract: An optical connector 21 has sleeves 25 and 25 placed between an optical fiber 40 and reception and transmission modules 26 and 27, wherein the N.A. of each sleeve 25 is larger than the N.A. of the optical fiber 40. A holder 36 forming a part of the sleeve 25 is made of a synthetic resin and can be colored. Further, the sleeve 25 is formed by cutting an optical fiber source line 52, etc.

Abstract: An optical fiber connector includes a housing, a ferrule, two pins, a ferrule boot, a pin holder, a spring, a spring push, a sleeve and a boot assembled in series. The ferrule defines two through holes, and the pin holder defines two mounting holes aligned with the through holes, allowing the pins to be inserted through the through holes into the mounting holes.

Abstract: An apparatus and a method for centering a core of a waveguide amplifier. One embodiment of the invention comprises axially rotating a waveguide which has a core, shining a light through a light transmission pathway in the core of the waveguide, and shaping an outer surface of the waveguide in a predetermined pattern with respect to the light transmission pathway.

Abstract: Optical fiber connectors each with a plurality of optical fibers protruding from the front surface of a main body by improved and uniform distances are produced by being subjected to an etching step in which a textile pad free of abrading particles and a slurry containing abrading particles of a relatively larger size are used and thereafter to a final fine polishing step in which a polishing pad with a porous and compressive sponge-like material without affixed abrading particles and a slurry of another kind containing relatively smaller abrading particles are used. The sponge-like material may be polyurethane and is required to have hardness and pores with sizes within specified ranges.

Abstract: A cleaning apparatus (100) for cleaning an endface (202) of an optical fiber contained within an interface device (200) is provided. The cleaning apparatus includes a housing (110) having an interface portion (116) adapted to be received by the interface device. The cleaning apparatus also includes at least a first nozzle (126) operable to deliver a pressurized gas and a solvent upon the endface to aid in the removal of contaminants on the endface. A method for cleaning an endface of an optical fiber contained within an interface device is also provided. The method comprises the steps of inserting an interface portion within the interface device so as to position a nozzle in proximity to the endface of the interface device. The method further comprises the steps of directing a pressurized gas through the nozzle toward the endface and intermixing a solvent with the pressurized gas.

Abstract: A system of making high density optical fiber arrays that includes securing the optical fiber ends in the housing front mask openings, then lapping the fiber ends and front mask forward surface to angle the fiber end front surfaces so that reflected wave energy does not interfere with optical signal data when transmitted during use. The opening pattern is preferably 2×2 to 128×128 or higher. Several alternate lap tool designs are disclosed including translational and rotating laps formed from solid bodies or a series of stacked plates. Standard slurry grinding and polishing compounds can be applied as desired. If a layer of epoxy originally covers the mask front face, it is removed by the lap tool as the fiber ends are lapped.

Abstract: An optical collimator (20) includes an optical fiber (21), a metal ferrule (22), a Graded Index (GRIN) lens (23) and an outer metal tube (24). The optical fiber has an exposed end (211) which is coated with metal. The exposed end of the optical fiber is inserted into the ferrule and laser welded thereto. The GRIN lens is also coated with metal. A plurality of soldering holes (241) is defined in a periphery of the outer tube. Solder is applied to the ferrule and the GRIN lens through the holes to firmly connect the outer tube, the ferrule and the GRIN lens together. After assembly, if the position of the GRIN lens or the optical fiber is found to be inaccurate, the GRIN lens and the ferrule can be easily resoldered.

Abstract: An optical module including a substrate having a groove; an optical waveguide layer formed on the substrate, the optical waveguide layer including an optical waveguide core having first and second ends, the first end being aligned with the groove, and an optical waveguide cladding covering the optical waveguide core; a ferrule having a through hole; and an optical fiber inserted and fixed in the through hole. The ferrule has a flat cut portion for semicylindrically exposing a part of the optical fiber inserted and fixed in the through hole. The ferrule is fixed at the flat cut portion to the substrate so that the part of the optical fiber exposed to the flat cut portion is inserted into the groove of the substrate until one end of the optical fiber abuts against the first end of the optical waveguide core.

Abstract: A ferrule assembly having highly protruding optical fibers and a corresponding method of efficiently, precisely and repeatedly fabricating the ferrule assemblies are provided. In this regard, a ferrule assembly is provided that includes a plurality of optical fibers extending at least about 3.5 &mgr;m beyond the front face. The end portions of the optical fibers of the ferrule assembly may also be substantially coplanar with the end portions of the optical fibers differing in position from one another by no more than 100 nm. The ferrule assembly may be efficiently fabricated by polishing the optical fibers to a desired protrusion without first grinding or polishing the optical fibers to be flush with the front face of the ferrule. The ferrule assembly may be even more efficiently fabricated in instances in which the ferrule includes at least one polishing feature, such as an outwardly extending pedestal or a recessed portion.

Abstract: In an optical device manufacturing method according to the present invention, a metal film is formed on a side surface of a bare fiber, a film is formed on an end face of the bare fiber, and, thereafter, the bare fiber is inserted into a ferrule until the end face of the bare fiber on which the film was formed is protruded from an end face of the ferrule, and then, the bare fiber is secured to the ferrule. In an optical device according to the present invention, a bare fiber having a side surface on which a metal film was formed is inserted into and secured to a ferrule, and an end face of the bare fiber is protruded from an end face of the ferrule, and a distance L between the end faces satisfies a relationship L<4×d (outer diameter of the bare fiber), and a film is formed on the end face of the bare fiber.

Abstract: A device includes a stub, and an optical fiber. The stub has an aperture, and a first end and a second end. The optical fiber is mounted in the aperture of the stub. The optical fiber has a first end and a second end. The first end of the optical fiber is polished so as to be flush with the first end of the stub. The second end of the optical fiber is cleaved at a predetermined position so as to provide for a predetermined length of the optical fiber measured from the first end of the optical fiber to the second end of the optical fiber.

Abstract: A fiber optic connector polishing fixture assembly for supporting a terminus of a fiber optic cable before a polishing surface. The assembly comprises: a fiber optic polishing fixture adapted to support the terminus before the polishing surface; a fixture support connected to the fixture for supporting the fixture before the polishing surface; and an adjustable connection between the fixture and the fixture support having user accessible adjustment controls for allowing a user to operate the controls to shift the fixture and fixture support relative to one another for substantially eliminating an apex offset of the terminus with respect to the polishing surface.

Abstract: A method of manufacturing an optical fiber end, provided with a face transparent to light waves, for attaching a ferrule, is described, in which the face is formed by cutting through the optical fiber and mechanical machining and the optical fiber is freed of its outer cladding, which completely encloses the outside of the optical fiber, in the region of an end section, the cutting through of the optical fiber (1) and the mechanical machining of the face (14, 15) being performed as a self-contained work step, which simultaneously includes the cutting through of the optical fiber (1) and the fine machining of the face (14, 15) obtained in this way, and the removal of the outer cladding (21, 22) in the region of the end section (23, 24) only being completed subsequently to this work step.

Abstract: An optical module including a substrate having a groove; an optical waveguide layer formed on the substrate, the optical waveguide layer including an optical waveguide core having first and second ends, the first end being aligned with the groove, and an optical waveguide cladding covering the optical waveguide core; a ferrule having a through hole; and an optical fiber inserted and fixed in the through hole. The ferrule has a flat cut portion for semicylindrically exposing a part of the optical fiber inserted and fixed in the through hole. The ferrule is fixed at the flat cut portion to the substrate so that the part of the optical fiber exposed to the flat cut portion is inserted into the groove of the substrate until one end of the optical fiber abuts against the first end of the optical waveguide core.

Abstract: Optical fiber connectors each with a plurality of optical fibers protruding from the front surface of a main body by improved and uniform distances are produced by being subjected to an etching step in which a textile pad free of abrading particles and a slurry containing abrading particles of a relatively larger size are used and thereafter to a final fine polishing step in which a polishing pad with a porous and compressive sponge-like material without affixed abrading particles and a slurry of another kind containing relatively smaller abrading particles are used. The sponge-like material may be polyurethane and is required to have hardness and pores with sizes within specified ranges.

Abstract: A cleaning tool for an optical connector cleans a connecting end face of a ferrule fixed to an optical connecting plug, and includes a cleaning sheet and a plug holding member. The cleaning sheet cleans the connecting end face of the ferrule. The plug holding member holds the optical connecting plug such that the connecting end face of the ferrule comes into contact with the cleaning sheet to be parallel to it.

Abstract: A ferrule with optical fiber is held to a ferrule holder. The ferrule is made of a material with 0.5˜2 times the wearing speed characteristic in comparison with a quartz glass. The ferrule holder comprises a polishing plate which has an elastic module equivalent to 70˜95 degrees of rubber hardness in a state of adhering a polishing sheet thereon. The ferrule holder is made to be self-supported on a polishing table in a manner such that the end face of the ferrule with optical fiber is in contact with the polishing sheet. The ferrule holder is made to manually move on the polishing table by a predetermined distance in the horizontal direction to slide the end face of the ferrule with optical fiber on the polishing sheet, thereby the end face of the ferrule with optical fiber is polished to a spherical convex surface centered on the optical fiber.

Abstract: A method for polishing an end face of a ferrule is disclosed herein. The ferrule includes an opening in which an optical fiber is positioned. The method includes the step of recessing an end of the optical fiber relative to the end face of the ferrule. The method also includes the step of polishing the end face of the ferrule after the end of the optical fiber has been recessed.

Abstract: An end face polishing method that can improve polishing accuracy of an end face of a ferrule and increase return loss in opposite connection is to be provided. In the end face polishing method in which the end face of a rod shape member is polished by pressing the rod shape member attached to a jig board to an abrasive member on a polishing board which is supported by a main body of an apparatus to be rotated and oscillated, by using the plurality of abrasive members whose hardnesses are higher than the rod shape member and different from the rod shape member, the end face of the rod shape member is polished with the abrasive members in a manner that the abrasive member is exchanged in the order from that of higher hardness to that of lower hardness.

Abstract: A method for optically joining an optical fiber array holder with an opponent member includes: disposing the plurality of optical fibers extending from the end face in a fiber array holder; polishing an end face of each of the plurality of optical fibers disposed in the fiber array block; removing the fiber array block from the plurality of optical fibers; and placing the plurality of optical fibers in corresponding guides formed in a waveguide substrate, the polished end faces of each of the plurality of optical fibers extending to an opponent member.

Abstract: A method for polishing an end face of a ferrule is disclosed herein. The ferrule includes an opening in which an optical fiber is positioned. The method includes the step of recessing an end of the optical fiber relative to the end face of the ferrule. The method also includes the step of polishing the end face of the ferrule after the end of the optical fiber has been recessed.

Abstract: A high density fiber terminator/connector and methods of making the high density fiber terminator/connector are provided. One method comprises using deep reactive ion etching to etch a plurality of holes through a silicon substrate, wherein each hole is sized to fit an optical fiber; placing an optical fiber in at least one hole; removing portions of the fibers such that one end of each fiber is substantially even with one side of the substrate; polishing a surface of the ends of the fibers and the side of the substrate that are substantially even; and forming a coating on the surface of the ends of the fibers and the side of the substrate that are substantially even.

Abstract: A method and apparatus is provided for mounting any one of a plurality of types of connectors upon the end portion of a fiber optic cable. The automated fiber optic connectorization apparatus includes a memory device for storing data relating to a plurality of types of connectors. The automated fiber optic connectorization apparatus also includes a controller for receiving input from a system operator or other source that specifies the type of connector to be mounted upon the specified fiber optic cable, the polishing geometry, and the optical performance specifications. Based upon this input, the controller determines the components required to mount the specified type of connector upon the end portion of the fiber optic cable based upon the data stored by the memory device. The automated fiber optic connectorization apparatus also includes means for obtaining the necessary components and means for assembling these components upon the end portion of the fiber optic cable.

Abstract: An optical fiber connector ferrule blank has, at its distal end, a pedestal region which has a bevel within a carefully chosen range of angles and a second bevel or chamfer which extends from the end of the first bevel at a different range of angles. The combination of first and second bevels makes possible a finished ferrule that can be used in a variety of different connectors while satisfying the manufacturer's requirement for pedestal diameter, angle of the second bevel, and the length of the combined bevels.

Abstract: The invention provides a hermetic fiber-optic seal, such as in an optical fiber ferrule or feedthrough, having an optical fiber, a glass solder for encasing at least a portion of the optical fiber, a first glass sleeve for encasing at least a first portion of the glass solder, a second glass sleeve for encasing at least a second portion of the glass solder, and an outer sleeve for encasing at least a portion of the first glass sleeve and the second glass sleeve. A gap filled with glass solder may be provided between the first glass sleeve and the second glass sleeve. The hermetic fiber-optic seal is made by an extrusion process.

Abstract: The capillary for optical fiber has an inner hole allowing an optical fiber to be inserted and retained therein. Ra value of the surface roughness of the inner hole is 0.1 &mgr;m to 0.5 &mgr;m. The ferrule for optical connector is provided with a chamfered part on one end of the capillary for optical fiber for guiding it into a sleeve and a flared part on the other end of the capillary for optical fiber for guiding the optical fiber into the inner hole.

Abstract: The present invention consists of a method and a structure formed by such method relating to optical fibers. Specifically, the invention consists of a chemical mill process for shaping the end of a fiber and thereby simultaneously forming both lens and precision mounting region. Also described is a self-aligning structure with integral lens. Both features improve light coupling. The lens focuses light energy entering and exiting the fiber. The precision mounting region facilitates alignment of fiber at couplings.

Abstract: The thermally conductive working body 25 having a rectangular parallelepiped shape is provided on the heating surface 21h of the hot plate 21 to protrude therefrom. The plastic optical fiber 2 is inserted into the ferrule portion 11 of the optical connector 10 and then positioned/held to cause its top end portion to protrude. The top end portion of the plastic optical fiber 2, that is projected to the top end side of the ferrule portion 11, is pushed against the mirror surface 25a of the thermally conductive working body 25 by inserting the thermally conductive working body 25 into the protection wall portion 16 of the optical connector 10 in the situation that the thermally conductive working body 25 is heated by the hot plate 21.

Abstract: Disclosed are a plastic optical fiber end surface processing method which allows formation of not only a convex semi-spherical surface but also of an arbitrary profile such as a concave semi-spherical surface, an apparatus for use in the method, a cutter for the method, and a plastic optical fiber connection method. At least the core portion of the end surface of a plastic optical fiber is cut into a semi-spherical surface by a semi-circular cutter, which is of a convex or a concave shape. This cutter is inserted into a through-hole of a holder and rotates therein. The plastic optical fiber is inserted into the through-hole of this holder, and end surface processing is effected by means of the rotating cutter.

Abstract: An end face polishing apparatus with improved polishing precision regardless of the length of ferrules when end faces of the ferrules are polished is provided. In an end face polishing apparatus polishing a rod-shaped member mounted at a polishing fixture by pressing the rod-shaped member against a lapping member on a lapping machine provided on a surface plate that is supported at the main body of the apparatus to rotate and rock, there are a plurality of rod-shaped guide members provided at the polishing fixture radially outwardly projecting and a tubular member capable of supporting the polishing fixture through the guide members on the surface plate. In this way, the guide members at the polishing fixture and the tubular member abut against each other so that the movement of the polishing fixture in the pressing direction is restricted.

Abstract: Optical fiber connectors each with a plurality of optical fibers protruding from the front surface of a main body by improved and uniform distances are produced by being subjected to an etching step in which a textile pad free of abrading particles and a slurry containing abrading particles of a relatively larger size are used and thereafter to a final fine polishing step in which a polishing pad with a porous and compressive sponge-like material without affixed abrading particles and a slurry of another kind containing relatively smaller abrading particles are used. The sponge-like material may be polyurethane and is required to have hardness and pores with sizes within specified ranges.