Abstract: Tape flutter, caused by head-to-tape stick-slip action, is suppressed in tape transport apparatus of the turnaround type having a single, speed-regulated capstan for metering magnetic tape into and out of a magnetic transducer station. To that end, a low-inertia motor, coupled to a turnaround roller, includes a tachometer for monitoring the instantaneous speed of the roller, and thereby the speed of the capstan tape loop. A phase lock loop, coupled to the tachometer, produces a composite signal including a nominal component corresponding to a desired tape speed, and an error component corresponding to tape flutter in the capstan loop. A bandpass filter, coupling the output of the phase lock loop and the motor, causes the motor to adjust the speed of the turnaround roller in phase opposition to the error component, to thereby suppress flutter in the capstan tape loop.

Abstract: A magneto-optic transducer for providing an optical indication of variations in magnetization in a magnetic storage medium located along a predetermined path. The transducer has a thin film of magneto-optic material with an edge positionable closely adjacent the storage medium path so that the magneto-optic film is magnetized in accordance with the magnetization in the storage medium. The magneto-optic film is supported such that polarized light projected along an incident optical path, convergent with the storage medium path at an acute angle, intercepts the magneto-optic film substantially normally and is reflected back generally along the incident optical path.

Abstract: A light sensing device comprises a photoconductive layer overlaying an array of PN junction diodes integrated within a semiconductor substrate. When a voltage is applied to the device to reverse bias the diodes, the voltage divides across the device in accordance with the capacitance of capacitive elements formed by the photoconductive layer and the junction capacitance of the diodes. When light impinges on the device, charge transfers from the photoconductive layer and accumulates at the underlying junctions at a rate that is directly dependent on the intensity of light incident on the corresponding portion of the photoconductive layer. When a diode reverse breakdown voltage is reached, the corresponding diode conducts. This causes an increase in current through the device, thereby signaling that a desired localized exposure has been attained.

Abstract: A film video player includes an electronic strobe light operable for repetitively firing a flash tube, to flash illuminate a solid state image sensor via a high-intensity light pulse projected onto photographic film at the vertical retrace rate of a standard television signal. A current sink circuit is provided for drawing a flash tube simmer current, to maintain an arc in the flash tube between sensor-illuminating pulses. Sensing circuitry, coupled to a junction common to the flash tube and the current sink circuit, produces a control signal corresponding to whether or not the flash tube is conducting simmer current. Switching circuitry, responsive to the control signal at the vertical retrace rate, (1) causes the overriding of the operation of a flash tube trigger circuit when the control signal indicates that the flash tube is conducting simmer current, and (2) causes the operating of the trigger circuit when the control signal indicates that the flash tube is not conducting simmer current.

Abstract: A film video player/printer allows an operator to display a video image of a photographic film in a normal orientation while magnifying and composing the magnified image according to a desired format (vertical or horizontal) portrayed by the display. Reticle-generating circuitry selectively rotates a rectangular reticle centered on the display, the reticle portraying the border and thereby the format of a print to be made. A turntable serves for selectively rotating the film about an optical centerline of the film video player/printer, to provide for the display of the film image in the normal viewing orientation and to provide for a print corresponding to the image and format displayed. With the film being rotated about the optical centerline and with the aspect ratio of a vertical reticle being the reciprocal of the aspect ratio of a horizontal reticle, an optical print is made without any need to compose or magnify the image to compensate for any rotation of the film for printing.

Abstract: An improved reinforcement member for a central aperture in a flexible recording disk and a method for forming the same. The improved reinforcement comprises an integral, annular-shaped ring formed on one or both sides of the flexible recording disk about the central aperture thereof. This improved reinforcement is formed by transfer printing a liquid image of the reinforcement member onto a side surface of the flexible recording disk and then subsequently solidifying that liquid image. The liquid image to be transfer printed onto the flexible recording disk is first established by filling a metering reservoir shaped to be an image of the reinforcement member with a solidifying liquid. A terminal end of compliant rubber tampon is then first contacted to the reservoir thereby picking up the liquid image which is then contacted to the surface of the flexible disk to be deposited there.

Abstract: A Faraday-effect magneto-optic transducer provides for optimizing the transmission of light through the transducer. A transparent supporting assembly for a planar element of magneto-optic material includes first and second reflectors on opposing sides of the element. The reflectors direct polarized light through the element substantially normal to its interface with the supporting assembly, for preventing light loss due to internal reflections as light is transmitted through the supporting assembly and magneto-optic element.

Abstract: An alignment disk including data tracks written in a spiral configuration, through the use of microstepping techniques, to accurately test a variety of transducer head parameters including head alignment, resolution and offset. The tracks include standard spiral tracks, S-shaped clamping spiral tracks and bordered spiral tracks, comprising a sequence of discrete address blocks each containing unique identifying information. The spacing of each address block is precisely known and because each is separately identifiable transducer head location can be precisely ascertained. The microstepping technique may also be employed to create a copy protected disk for disk drives having half-track read and write capabilities.

Abstract: A film video player/printer provides for cropping a photographic film by displaying the film image on a video monitor, the display consisting of not only the image to be included in an optical print but the image to be excluded, just off the print. Reticle-generating circuitry serves to display and to rotate a given rectangular reticle centered within the border of the image displayed, the perimeter and the orientation of the reticle defining respectively the portion of the image to be printed and the format of the print to be made. To further facilitate cropping, border logic and control circuitry, operable prior to a photographic printing operation, serves for blanking-out the portion of the image displayed outside of the reticle, so that the video image temporarily corresponds exactly to the print to be made.

Abstract: Apparatus for automatically adjusting the azimuth angle of a transducer head relative to a media recording surface when the transducer head is driven in a non-radial path about the media recording surface with a transducer head supported by a positioning support shaft located within a head carriage. The head carriage receives drive forces from a worm gear and the positioning support shaft is attached to a control shaft and a positioning shaft for azimuth angle alignment during head carriage movement.

Abstract: A Faraday-effect magneto-optic transducer of a rotary form includes first and second optical fibers having adjacent ends aligned with each other for joint rotation along a circular path. Opposing surfaces of a planar element of a magneto-optic material are attached respectively to the adjacent ends of the fibers for rotation therewith. The first fiber is arranged with respect to a light source for scanning an entering beam of polarized light along the circular path, a portion of which is immediately adjacent and substantially parallel to the information-bearing surface of a magnetic storage device, such as magnetic tape. The planar element modulates the entering light according to the magnetization of the region of the storage device adjacent the magneto-optic material.

Abstract: A reel assembly apparatus for coaxial magnetic tape reels is provided in which both an inboard reel and an outboard reel may be reliably clamped to their respective drive spindles from the outboard side of the assembly apparatus with ease and convenience. For the purpose of clamping the inboard reel, an internal locking nut extends radially in the plane of the inboard reel from its drive spindle into threading engagement with a hub of the inboard reel. A linkage, extending axially through the outboard drive spindle, rotates in response to turning movement of a bail accessible to an operator. The locking nut, in response to the rotation of the linkage, (1) initially causes the inboard hub to rotate, relative to the inboard reel, a limited amount into a reel-clamping position, and (2) then causes an axial movement of the inboard hub. This latter movement drives the inboard reel axially, to clamp it against a radially extending member of the inboard drive spindle.

Abstract: A flexible magnetic recording media, such as disks or magnetic tape, having a non-magnetic layer intermediate the substrate and magnetic recording layers providing improved durability of the magnetic recording layer including a binder comprised of non-magnetic particles of .alpha.Fe.sub.2 O.sub.3 with similar physical properties as those of the magnetic recording layer (.gamma.Fe.sub.2 O.sub.3 or Co-.gamma.Fe.sub.2 O.sub.3) and a reservoir of lubricant.

Abstract: Tracking control apparatus for a magnetic storage device is provided for playback of information recorded on tracks at alternating azimuth angles which correspond to mutually different azimuth angles of a pair of magnetic playback heads. The playback heads have track-wise widths which are less than the width of their associated record tracks, to prevent the attenuation of their playback signals resulting from limited playback head tracking error. A tracking control head, which has an azimuth angle of one of the playback heads, is mounted for selectively overlapping adjacent record tracks in accordance with the magnitude and direction of the tracking error of the playback heads. Signal comparison circuitry produces a tracking error signal in accordance with the difference between the output of the control head and the output of a playback head.

Abstract: A tape guide mechanism includes an edge-guide element extending radially from a central axis. A tape guide roller, rotatable about the central axis, is arranged for urging an advancing magnetic tape laterally in the direction of the edge-guide element, to maintain an edge of the tape perpendicular to and in continuous contact with the edge-guide element during tape transport movement. A piezoelectric actuator, preferably comprising a stack of flexing type bimorph elements responsive to a voltage signal relating to the direction and magnitude of a tape-tracking error, causes movement of the edge-guide element in a single composite direction having a first component which is perpendicular to the edge of the tape, and a second component, which is parallel to the tape edge.

Abstract: Improved light reflector apparatus for use in an electronic flash unit or the like is formed by an injection molding operation, which causes both precise shaping of a reflector and accurate mounting of the reflector securely within a housing. A light-reflecting flexible sheet is placed in a mold so that its light-reflecting front surface is centrally positioned adjacent a mold forming surface. The forming surface, which is larger than the sheet, has a contour adapted for shaping the sheet to reflect light into a beam of illumination. Liquid plastic is injected into the mold under pressure against the opposite surface of the sheet, thus pressing its light-reflecting surface into intimate contact against the forming surface. Because the sheet is smaller, the border of the forming surface is not covered by the sheet. Plastic flows beyond outer edges of the sheet against the uncovered border of the forming surface.

Abstract: An energy-saving electronic flash unit for a rapid sequence of flash exposures includes status indicator apparatus operable for signaling the readiness of the flash unit for the next flash in the sequence as a function of the flash energy expended to produce the previous flash. When the energy retained by a flash-firing capacitor at the termination of the preceding flash exceeds the energy expended in producing that flash, energy-monitoring circuitry causes a status indicator device to signal that the flash unit is sufficiently charged for the next exposure in the sequence.

Abstract: Aluminum metal runs and bonding pads on an integrated circuit die are passivated, subsequent to wire bonding of the circuit die to a lead frame, by immersing the lead frame and wire-bonded die in hot deionized water for approximately 60 minutes.

Abstract: Improved light reflector apparatus for use in an electronic flash unit or the like is formed by an injection molding operation, which causes both precise shaping of a reflector and accurate mounting of the reflector securely within a housing. A light-reflecting flexible sheet is placed in a mold so that its light-reflecting front surface is centrally positioned adjacent a mold forming surface. The forming surface, which is larger than the sheet, has a contour adapted for shaping the sheet to reflect light into a beam of illumination. Liquid plastic is injected into the mold under pressure against the opposite surface of the sheet, thus pressing its light-reflecting surface into intimate contact against the forming surface. Because the sheet is smaller, the border of the forming surface is not covered by the sheet. Plastic flows beyond outer edges of the sheet against the uncovered border of the forming surface.

Abstract: Exposure control apparatus adapted for use with a computer having an inexpensive, uncalibrated clock includes a pair of covariant, internal reference signal sources, an integrator and a comparator that produces a time interval signal when an electrical parameter of the integrator reaches a threshold level established by the comparator. With the covariant reference signal sources connected to the integrator, the computer calculates an initial clock correction factor that is stored in the computer's memory. A standard light source of known intensity, which is used only once, is then coupled to the integrator through a photoresponsive device and the initial clock correction factor is used by the computer to provide compensation for the computer clock during an exposure operation. In the field, the computer, prior to each exposure operation, connects the covariant reference signal sources to the integrator and calculates an updated clock correction factor.