Abstract: An improved slider and magnetic cap assembly which reduces flux loss which retards sensitivity in writing and reading in a magnetic head system. The slider incorporates a body, a partial core, a coil and a cap. The cap is mounted on the upper surface of the body and includes a first and second depending projection corresponding in shape and location to the generally U-shaped partial core so that the mating surfaces of the cap and the partial core mate directly. Another aspect of the invention is a similar slider assembly wherein the cap includes a film coil of electrically conductive material deposited around an area which mates with the partial core so that the flow of electrical current will induce magnetic flux through the core. Another aspect of the invention is a method of making a magnetic head slider wherein the back bar of a generally rectangular tube is removed and a partial core is sliced from the tube.

Abstract: An apparatus for evaluation of radiation beam geometry that finds application in determining the focus of an illuminating beam relative to an optical disk is disclosed herein. In one preferred embodiment, a light source generates a linearly polarized beam which is collimated by a collimating lens. The collimated beam is then converged by an objective lens onto the surface of the optical disk. The disk reflects the illuminating beam focused thereon back through the objective lens to a beam splitter. A portion of the optical energy incident on the beam splitter is then redirected to form a servo beam, wherein the degree of collimation of the servo beam is indicative of the focus position of the illuminating beam. A beam separation module, based on frustrated total reflection, having a reflectivity which varies in response to the angle of incidence of optical energy thereon is positioned to intercept the servo beam.

Abstract: An improved slider and magnetic cap assembly which reduces flux loss which retards sensitivity in writing and reading in a magnetic head system. The slider incorporates a body, a partial core, a coil and a cap. The cap is mounted on the upper surface of the body and includes a first and second depending projection corresponding in shape and location to the generally U-shaped partial core so that the mating surfaces of the cap and the partial core mate directly. Another aspect is a similar slider assembly wherein the cap includes a film coil of electrically conductive material deposited around an area which mates with the partial core so that the flow of electrical current will induce magnetic flux through the core. Another aspect is a method of making a magnetic head slider wherein the back bar of a generally rectangular tube is removed and a partial core is sliced from the tube.

Abstract: A two-axis electromagnetic actuator for positioning an objective lens in an optical recording system is disclosed wherein the objective lens is mounted on a lens holder. The lens holder is positioned within a magnetic field created by two pairs of permanent magnets. A tracking coil is wound around the lens holder and two focus coils are affixed to the tracking coil adjacent the permanent magnet pairs. The lens holder suspended between the magnet pairs by flexures supported on a circuit board. The circuit board further includes electrical contacts for supplying current to the focus and tracking coils in accordance with feedback signals generated by a servo system. The current through the coils interacts with the magnetic field produced by the magnets to move the lens holder and objective lens carried thereon and effect tracking and focusing of a laser beam exiting the lens upon the surface of an optical disc.

Abstract: The present invention discloses texturing of the slider air bearing surfaces of the magnetic heads in disk drives to reduce stiction that retards take-off and displaces critical lubricant in a magnetic head system. One embodiment of the present invention utilizes nonuniform etching of chemically identical components of a ferrite slider material due solely to random crystal orientation relative to the exposed surface. Another embodiment of the present invention utilizes a photoresist of a type used in making printed circuit boards, to form a pattern. Subsequently, the surface may be etched to form the antistiction properties. A variety of controlled and reproducible patterns as well as a controlled depth of pattern may be utilized.

Abstract: A multi-element, air-spaced prism system for use in a reflective-type optical media device having a light source to provide an incident light beam provides an achromatic, anamorphic prism which corrects for astigmatism and ellipticity in the light beam from the light source. One embodiment of the prism system provides at least two reflections of a return beam from the reflective-type optical media. The return prism provides these reflections from various optical surfaces in the multi-element prism system. In one embodiment, the prism system also provides a reflection of a portion of the incident beam. This reflection is directed to a detector which can, for instance, monitor the intensity of the light beam.

Abstract: An apparatus and a method for determining the time difference between electrical events utilizes a sinusoidal signal as a reference from which to determine the elapsed time between events represented as electrical pulses. A sine wave and a cosine wave are multiplexed to produce the sinusoidal reference signal. When an event occurs, as indicated by an electrical pulse, the sine wave and the cosine wave are sampled to produce two digital values. A comparator determines which of the two digital values falls within a predetermined range, and transmits a select signal to multiplexer. The multiplexer selects the digital value which falls within the predetermined range. The selected digital value corresponds to an angle value which can be uniquely determined within one cycle of the sinusoidal reference signal. A cycle counter accounts for the number of full cycles which elapse until the next event is detected.

Abstract: An optical disc player/recorder incorporates a laser, and an electromagnetically driven objective lens. The objective lens is mounted to a lensholder which is movable with respect to a base. A single pair of permanent magnets are mounted to the lensholder, and two pair of electromagnetic coils are mounted to the base. The coils and magnets are positioned such that one set of coils is collinear with the direction of magnetization of the permanent magnets and the other set of coils is perpendicular to the direction of magnetization of the magnets. Electromagnetic fields generated by the coils are used to move the objective lens in either a focus direction or a tracking direction. The magnets are mounted on the moveable objective lensholder, while the coils are attached in a heat-sink relationship to the fitted base. The objective lens rests on top of the objective lensholder which is suspended with respect to the base by a pair of flexures.

Abstract: A magnetic head slider suspension assembly for loading a head slider having air bearing surface onto the surface of a magnetic rotating disc is shown. The magnetic head slider suspension assembly includes an elongated slider arm adapted to be attached to an arm mounting support. The elongated slider arm includes a deflectable central arm section or load beam having a support end at one end thereof operatively attached to the arm mounting support and a head/slider loading end located at the other end thereof. The central arm section is generally rectangular in shape and has a predetermined width at the support end and a width which may be equal to or less than the predetermined width at the head/slider loading end. The central arm section has at least one raised load rail extending substantially perpendicular therefrom and in the same direction as that of a head slider operatively attached to the head/slider loading end.

Abstract: A small solder tip, which advantageously allows for the rapid production of reliable solder joints without the addition of extra solder, flux or striping the insulation on the wire. The solder tip is preferably formed of tungsten carbide and is used in conjunction with a reflow power supply. In a specific application, the solder tip is utilized for hook-up of magnetic head wires to solder pads. The solder tip comprises a center shaft which allows expanding gases to escape in order to prevent solder from being squeezed out by the pressure build up. The base extremity of the solder tip which contacts the wire is structured with a stepped surface having an opening for accepting the wire therethrough and a projecting leg for contacting the wire and immersing the wire in molten solder. The solder tip additionally comprises a room which provides space for excess solder, enabling the solder tip to accommodate larger variation in solder volume on the pads.

Abstract: A read head assembly senses information recorded on magnetic media from tracks having different widths. The read head comprises a magnetoresistive strip which is positioned normal to the direction of movement of the magnetic media. In a preferred embodiment, the magnetoresistive strip includes two pairs of signal conducting leads, one pair of which has a lead spacing approximately equal to a first relatively narrow track width, and the other pair having a spacing approximately equal to a second, relatively wide track width.

Abstract: A head core slider for a rigid magnetic disk drive, including a slider body, a track portion, a yoke portion and a narrow stepped portion. The slider body has two spaced-apart parallel air bearing portions, and the track portion is formed integrally with at least one of the bearing portions, so as to extend from one end of the bearing portion in the direction of length of the bearing portion. The track portion has the same height as the bearing portion, and a width smaller than that of the bearing portion. The yoke portion is formed integrally with the track portion, so as to extend from one end of the track portion remote from the bearing portion, and has a protrusion of the same height as the track portion. The width of the protrusion is smaller than that of the bearing portion and larger than that of the track portion.

Abstract: The surface of a slider for a magnetic recording head, a burnishing head, or a glide head includes a pair of rails that, in operation, face the magnetic recording medium to form air bearing surfaces. These air bearing surfaces have slots cut into them at the same prescribed angle relative to the longitudinal axis of the slider, and along a single straight line. This provides slots which are asymmetric about the longitudinal axis, causing the slider to fly nearer the recording medium and at almost constant height.

Abstract: The present invention is a method for constructing dual stripe magnetoresistive read heads by depositing each stripe on a separate substrate and then bringing the stripes together in the assembly process. The method of the present invention first forms two substrates and deposits a layer from which conductor leads and stripes will be defined upon them. Connecting pads are provided to allow all the conductor leads to terminate on one substrate and connect with a standard flex circuit. After the leads and stripes are defined, a layer of insulation is then placed over the stripes, leads and substrates. Finally, the substrates are shaped to the preferred from and mounted together to form a recording head with the magnetoresistive stripes precisely positioned adjacent to each other. Advantageously, this method permits the deposition of the MR strips at the same time and under the same deposition conditions.

Abstract: A magnetic head slider suspension assembly for loading a head slider having air bearing surface onto the surface of a magnetic rotating disc is shown. The magnetic head slider suspension assembly includes an elongated slider arm adapted to be attached to an arm mounting support. The elongated slider arm includes a deflectable central arm section or load beam having a support end at one end thereof operatively attached to the arm mounting support and a head/slider loading end located at the other end thereof. The central arm section is generally rectangular in shape and has a predetermined width at the support end and a width which may be equal to or less than the predetermined width at the head/slider loading end. The central arm section has at least one raised load rail extending substantially perpendicular therefrom and in the same direction as that of a head slider operatively attached to the head/slider loading end.

Abstract: The present invention discloses texturing of the slider air bearing surfaces of the magnetic heads in disk drives to reduce stiction that retards take-off and displaces critical lubricant in a magnetic head system. One embodiment of the present invention utilizes nonuniform etching of chemically identical components of a ferrite slider material due solely to random crystal orientation relative to the exposed surface. Another embodiment of the present invention utilizes a photoresist of a type used in making printed circuit boards, to form a pattern. Subseqeuntly, the surface may be etched to form the antistiction properties. A variety of controlled and reproducible patterns as well as a controlled depth of pattern may be utilized.

Abstract: A load beam adapted for use in a head slider suspension assembly is shown. The load beam has a generally rectangular shape and includes a member for defining a support arm end and a head/slider loading end. The load beam has a torsional vibration mode characteristic which, upon said load beam being excited by a driving force, produces a fundamental mode vibration in the range of about 2000 hertz to about 4000 hertz and higher order mode vibrations above about 6000 hertz. In the preferred embodiment, the load beam has at least one load rail extending substantially perpendicular therefrom. The at least one load rail can be selected to extend from the load beam in a direction the same as or opposite to the direction in which a head/slider assembly is supported from a head/slider loading end of the load beam.

Abstract: Method for producing a head core slider for a rigid magnetic disk drive, including a ferrite slider body having a pair of air bearing portions which have a predetermined height and are spaced apart from each other in a transverse direction perpendicular to a direction of extension thereof, and further including a pair of ferrite yoke portions formed integrally with the slider body. The yoke portions cooperate with the slider body to form a first and a second closed magnetic path and define therebetween a first and a second magnetic gap. The slider body and the yoke portions cooperate to provide a first and a second track portion in which the first and second magnetic gaps are open, respectively. The first and second track portions have sliding surfaces which have the same height as the air bearing portions. The first track portion is used exclusively for an information writing operation, while the second track portion is used exclusively for an information reading operation.

Abstract: A head core slider for a rigid magnetic disk drive, and a method of producing the same. The core slider includes a slider body, a track portion, a yoke portion and a narrow stepped portion. The slider body has two spaced-apart parallel air bearing portions, and the track portion is formed integrally with at least one of the bearing portions, so as to extend from one end of the bearing portion in the direction of length of the bearing portion. The track portion has the same height as the bearing portion, and a width smaller than that of the bearing portion. The yoke portion is formed integrally with the track portion, so as to extend from one end of the track portion remote from the bearing portion, and has a protrusion of the same height as the track portion. The width of the protrusion is smaller than that of the bearing portion and larger than that of the track portion.

Abstract: An optical element microstructure detects changes in the propagation angle of an optical beam on a local basis. The optical element microstructure preferably comprises an array of structures which are small compared to the size of the beam. Detection is done on a local basis, with each optical element in the microstructure array perturbing the optical beam in a predictable manner. By virtue of the number of optical sensing elements, the microstructure array is less sensitive to flaws in the optical elements, as compared to a single optical component placed in the path of the light. In addition, the microstructure lends itself to mass production by replication, and other low cost methods such as injection molding.