Abstract: Bars of integral laser diode devices cleaved from a wafer are placed with their p regions abutting and n regions abutting. A thin BeCu mask having alternate openings and strips of the same width as the end facets is used to mask the n region interfaces so that multiple bars can be partially coated over their exposed p regions with a reflective or partial reflective coating. The partial coating permits identification of the emitting facet from the fully coated back facet during a later device mounting procedure.

Abstract: The invention is a semiconductor device assembly and method of making the same. A mounting plate has positioning means for positioning the plate relative to a header, a first mounting surface of the plate is attached to the header and a semiconductor device is attached to a second mounting surface of the mounting plate. The assembly is made by forming the mounting plate, positioning the mounting plate relative to the header by the positioning means, attaching the first mounting surface to the header and the semiconductor device to the second mounting surface. Another method of making the assembly is by defining and etching a mounting plate and attaching the first mounting surface to the header and the semiconductor device to the second mounting surface. This assembly and process provides an efficient means for mounting semiconductor devices and in particular electro-optic devices such as lasers.

Abstract: The invention is a semiconductor device assembly and method of making the same. A mounting plate has positioning means for positioning the plate relative to a header, a first mounting surface of the plate is attached to the header and a semiconductor device is attached to a second mounting surface of the mounting plate. The assembly is made by forming the mounting plate, positioning the mounting plate relative to the header by the positioning means, attaching the first mounting surface to the header and the semiconductor device to the second mounting surface. Another method of making the assembly is by defining and etching a mounting plate and attaching the first mounting surface to the header and the semiconductor device to the second mounting surface. This assembly and process provides an efficient means for mounting semiconductor devices and in particular electro-optic devices such as lasers.

Abstract: A method of polishing a roof-shaped, or bevelled, tip having a predetermined angle on the end of an optical fiber is disclosed. The method comprises placing an optical fiber in contact with an abrasive tape at an angle corresponding to the desired predetermined angle. The fiber is moved towards the tape beyond the point of contact so as to cause a bend in the fiber. Upon moving the abrasive tape, the compliance of the fiber, by virtue of the bend, provides a pressure of the fiber against the tape to enable polishing to occur. As polishing continues the pressure decreases until enough material is removed so as to eliminate the bend and impart the predetermined angle to the fiber tip. The fiber may be rotated to polish the other side in a similar manner, if so desired.

Abstract: A pickup cartridge comprises a stylus arm having a stylus disposed at one end, and having the other end thereof flexibly supported in the cartridge. A flylead connects an electrode arranged on the stylus to a terminal mounted on the cartridge. In accordance with the instant invention, the stylus flylead is covered with a damping compound to improve the reliability of high speed scanning of the disc.

Abstract: In a record playback system, which includes a carriage within which a stylus arm is mounted, it is desired to clean the stylus tip from time to time. The apparatus according to the present invention lowers and lifts the stylus so as to effect stylus-record engagement and disengagement and in addition the same apparatus cleans the stylus tip during the lowering-lifting cycle.

Abstract: A capacitive information disc playback stylus comprising a dielectric support element having in one portion a conical body terminating in a constricted tip. The tip comprises a curved prow surface, a flat electrode surface remote from the prow, shoulders joining the constricted tip to the conical body, and side surfaces which join the prow and the flat surface. The side surfaces, the flat surface, and the prow surface define the edges of a disc-engaging surface.

Abstract: A playback stylus for a capacitive information disc comprising a shank, a dielectric material at one end of the shank, a first conical region of a first angle in an end portion of the dielectric material, a second conical region adjacent to the first conical region of a second angle less than the first angle, and an information recovering terminal region in the first conical region for recovering information recorded in an information track of a capacitive information disc.

Abstract: A method for lapping two flats of substantially the same dimensions in an element having a cone-shaped tip. The method includes the steps of contacting a first region of the cone wherein a flat is to be lapped while the cone is in contact with the lapping surface; rotating the element to a second region wherein a second flat is to be lapped while the tip is in contact with the lapping surface without the cone tip contacting or disturbing the lapping surface; contacting the second region of the cone with the abrasive lapping surface for a predetermined time; and repeating the previous steps until the two flats have been lapped. The time each region contacts the lapping surface is substantially equal and the time during which the element is rotated is small compared to the time each region contacts the lapping surface.

Abstract: A lifting-lowering assembly for a stylus arm employs two flat portions having a pivot axis in the vicinity of the intersection of the two portions, a stylus arm rest on the first portion, and, an upwardly extending member on the second portion. The upwardly extending member cooperates with an electromagnetic device to rotate the assembly about the pivot axis. Air trapped under the first and second flat portions tends to permit gentle lifting and lowering operations by damping the rotational motion of the assembly.

Abstract: An apparatus for grinding two flats of substantially the same dimensions in portions of a conical tip of an element. The apparatus comprises, in combination, a rotatably mounted holding member for holding the element; a rotatably mounted abrasive surface for grinding the tip portion; an index wheel drivingly connected to a flipping lever on the holding member for rotating the element between the two tip portions wherein the point of the tip does not disturb or penetrate the abrasive surface during rotation; and a pivot bearing upon which the holding member is pivotally mounted for contacting the tip portions with the abrasive surface so that a constant force is applied to the tip portion being ground, wherein the tip point does not disturb or penetrate the abrasive surface and wherein the tip remains in contact with the abrasive surface during rotation.

Abstract: Apparatus for orienting a cutting stylus having a mounting face and a cutting face includes a base member having a flat, nonadhesive surface and a stylus holding fixture. The stylus holding fixture includes a mounting block having a surface vertical to the flat, nonadhesive surface of the base member. The cutting stylus is attached with epoxy to the vertical surface of the mounting block which forms the proper angle to orient the cutting face of the stylus for subsequent lapping on a lapping machine. A capping plate having a recess for the cutting stylus is attached to the mounting face of the mounting block. With the stylus mounted in the mounting block the stylus holding fixture may now be placed on a lapping machine for the stylus lapping process.

Abstract: Apparatus for sharpening a diamond cutting stylus for use in recording video signal information in a metal master includes a source of high energy particles such as an ion milling machine. The high energy source provides a beam of high energy particles having a cross-sectional area perpendicular to the longitudinal axis of the beam that is large compared to a given area on a mounting face of the stylus which is to be bombarded by the beam during the sharpening operation. Further, the apparatus includes a masking block for masking a first portion of the cutting stylus. The masking block is positioned with respect to the high energy source to intercept the particles in the beam directed at the first portion of the cutting stylus. A second portion of the cutting stylus which includes the given area is exposed to the high energy particles such that the second portion of the cutting stylus is removed.

Abstract: A stylus assembly for damping impulsive radial motion of the stylus during playback of a grooved video disc record. Included in the stylus assembly is a moment arm perpendicularly attached at the free end of the stylus arm and parallel to the disc record when the stylus is engaged for playback. A mass is mounted to the moment arm to contribute increased inertia to lateral motion of the stylus only in a direction radially across the record. The mass is designed to permit tracking a record groove in the presence of groove eccentricity but to resist motion due to impulsive forces imparted by record defects or particulate matter thereon.

Abstract: A method of lapping the sharp point of a hard material using a silicon oxide, glow discharge deposited abrasive layer wherein the abrasive layer is thick enough to prevent penetration of the point into the substrate.

Abstract: A composite stylus assembly, provided for a grooved disc record playback system, includes a playback stylus supported on a free end of an arm. The other end of the arm is supported by a flexible mount in a cartridge. The stylus rides in the groove of the record for information recovery. The arm is located within a hollow tube which is supported at one end thereof by the flexible mount. The free end of the tube includes a mechanism which aids in the steady inward movement of the tube relative to the disc center when relative motion between the disc and the playback stylus is established. When the playback stylus retraces the same groove convolution, the inward motion of the hollow tube exerts enough force on the stylus arm to enable the playback stylus to ride over the walls of the groove.

Abstract: A composite stylus assembly, provided for a system for playing back a grooved disc record, includes an L-shaped leaf spring support member formed of a longitudinal piece and a short transverse piece. The transverse piece is attached near the free end of a pickup arm of the system such that the longitudinal piece will be substantially parallel to the pickup arm. The pickup arm is supported in a cartridge adapted for reception within a carriage of the system such that during record playback, the longitudinal piece will lie between the pickup arm and the center of a turntable of the playback system. A playback stylus, subject to engagement with the groove of a video disc record supported on the turntable, is carried at the free end of the pickup arm, while a pre-play stylus, subject to simultaneous engagement with several convolutions of the groove of the disc record, is carried at the free end of the longitudinal piece.