Abstract: An amorphous thin magnetic film having stabilized uniaxial anisotropy of thickness 200-1000 angstroms is fabricated from an alloy of composition CoX where X is one of the elements Zr, Nb, Mo, Ta, Ru, Rh, Pd, Hf, Ti, W, Re, Os, Ir. The invention teaches setting the magnitude of the uniaxial anisotropy of the film at a predetermined magnitude and stabilizing the anisotropy against long term change through (1) the addition of controlled amounts of silicon to the alloy, (2) cladding each face of the film with an Si02 layer, and (3) stabilizing and annealing the resultant clad film in a two step process.

Abstract: Color image reproduction apparatus, including a video monitor and a computer-based workstation, provides for modifying an original color image read from an input film and for writing a reproduced image on an output film. A plurality of digitally operated look-up tables (LUTs), associated with the workstation, serve for transforming original imaging data to a common color space (CIELUV L* u* v*) and for transforming reproduced imaging data to different use-dependent RGB color spaces, e.g. video monitor, output film, etc. Color image values stored in each LUT are altered from exact color image values by means of a least squares algorithm to provide an average error of zero--an unbiased error--for linearly interpolated values derived from each LUT.

Abstract: The invention teaches modifying the shape of a bar magnet which is uniformly magnetized either in the direction of its height or width to increase the volume of magnetic material at each end of the magnet. This results in increased magnetic field contribution from the magnet ends which modifies the field direction at the magnet faces so that the field lines converge rather than diverge just as they enter and leave the central portion of the magnet. Further along the field direction, the field lines change from being convergent to again being divergent, as is the usual case for a conventional bar magnet. Because of this transition there is an extended region over which the field lines are effectively straight and parallel, i.e. the field is uniform. This uniformity has been attained without increasing the length of the magnet, and a bar magnet so modified according to the teaching of the invention is suitable for the uniform biasing of MR elements in a single track or in a multitrack head.

Abstract: A previously disclosed "C" shaped thin film deposited permanent magnetic structure of essentially symmetrical form is designed to provide a planar region of transverse field with little or no longitudinal field component. Practice of the present invention teaches asymmetrically modifying the "C" shaped magnet to restore a small controlled amount of unidirectional longitudinal field component. The symmetry is broken by either angling the direction of magnetization of the magnet relative to the symmetric geometric form of the structure, or by angling the direction of the magnetization and also changing the geometric shape of the magnet from a "C" shape to an "L" shape.The resultant field distribution of the deposited asymmetrical magnetic structure produces a magnetic field of sufficient strength for biasing the hard axis of a coplanarly deposited MR element with an additional relatively smaller magnitude unidirectional easy axis field for longitudinally biasing it.

Abstract: Image scanner apparatus of the drum type includes a hollow, rotatable drum having an aperture on its curved surface corresponding to the size of an image to be scanned, and a light source, disposed inside the drum between its surface of revolution and its axis of rotation, for projecting image-scanning light through the aperture of the drum. A mechanism mounts a flexible image-bearing film immediately adjacent the drum, in a curved plane substantially parallel with the curved surface of the drum and in registration with the aperture on its curved surface, such that a film image to be scanned is free of drum support.

Abstract: Color image reproduction apparatus includes a video monitor for displaying a reproduced image (a soft copy) to appear on any of a variety of image-receptive output media (reversal film or negative film to print material or reversal film to print material) in which color of the reproduced image may vary from one type of output medium to another. A computer-based workstation, having a series of look-up tables for transforming imaging data to a variety of monitor-dependent RGB color spaces, enables the video monitor to show a series of displays of the reproduced image with each version of the reproduced image being visually matched to the reproduced image as it would appear on a particular one of the image-receptive output media.

Abstract: A lighttight box, for automatically delivering a photosensitive sheet of photographic film to an exposure station, includes a lid movable between a first lighttight position and a second box-opening posiiton. A clamshell film-carrying mechanism, connected to the lid, is mounted for movement (1) from a closed position internal to the box when the lid is in its lighttight position, to (2) an open film-delivery position external to the box when the lid is in its box-opening position.

Abstract: Color image reproduction apparatus, including a video monitor and a computer-based workstation, provides for reading a color image from an input film and for writing a reproduced image on an output film. A plurality of digitally operated look-up tables (LUTs), associated with the workstation, serve for transforming original imaging data to a common color space (CIELUV L* u* v*) and for transforming reproduced imaging data to different use-dependent RGB color spaces, e.g. video monitor, output film, etc. Output color image values stored in each LUT are computed off-line by means of a least squares algorithm applied to an input data set augmented by the second derivative of the function represented by the data set.

Abstract: Image scanner apparatus includes a drum having an aperture rotatable about an axis. A mechanism clamps a border of an exposed photographic film to the drum, with the film image aligned with the aperture substantially in a surface of revolution of the drum. A source of diffuse light, disposed between the rotational axis of the drum and its surface of revolution, projects a line of diffuse illumination through the aperture directly onto the film image. Lens apparatus, interposed between the surface of revolution of the drum and a linear image sensor, focuses a line of diffuse light, modulated in accordance with the film image, onto the sensor.

Abstract: A device, for simulating temperature effects at the interface of a head-to-medium interface, is comprised of a unitary block of material which transmits radiation in the infrared (IR) region of the electromagnetic spectrum and which has a wear-resistant property substantially approximating that of the material of an actual magnetic head to be simulated. The unitary block is shaped to have (1) a first forwardly facing surface substantially approximating the dimensions and contour of the working surface of the head to be simulated, and (2) a second rearwardly facing surface substantially approximating the dimensions and contour of a light-transmitting surface of a positive spherical lens the focal plane of which coincides with the forwardly facing surface. Sapphire is selected as a material having a suitable IR-transmitting property and a wear-resistant-property commensurate with one wear-resistant properties of alloy and ferrite materials commonly used in the manufacture of a video magnetic head.

Abstract: An illumination system for image scanner apparatus that varies the amount of light in an object (film) plane as a function of field angle, to render irradiance at an image sensor relatively uniform with field angle. In a preferred embodiment, an optical converter regulates the irradiance in the object plane as a function of field angle by varying the power radiated along a line of diffuse light projected onto the object plane.

Abstract: Spectrometer apparatus, for self-calibrating a color image scanner of the line scanner or area scanner type, comprises a member, having an optical slit, movable into position on an optical axis of the scanner between its polychromatic light source and its focusable lens in a plane occupied by a color image when it is scanned. A diffraction grating is similarly movable onto the optical axis, a given distance from an image sensor of the scanner. The light source illuminates the slit and the diffraction grating disperses transmitted polychromatic light according to its wavelength, forming duplicate spectra off-axis across respective halves of the image sensor, with longer wavelengths being diverted to respectively higher angles.

Abstract: A lighttight box includes a lid movable between a first lighttight position and a second box-opening position. A clamshell film-carrying mechanism, connected to the lid, is mounted for movement (1) for a retracted position internal to the box when the lid is in its lighttight position, to (2) an extracted film-delivery position external to the box when the lid is in its box-opening position. Actuator apparatus includes a lift mechanism, attachable to the lid when the box is in a parked film-delivery position relative to a workstation, movable between a rest position in which the lid is held in its closed position, and an actuated position in which the lid is held in its box-opening position. A motor, coupled to the lift mechanism, serves for driving the lift mechanism between its rest and actuated positions.

Abstract: An environmental indicator assembly in a floppy disk cassette provides a warning signal when the cassette has been subjected to either a high-moisture or a high-temperature condition either environment being potentially harmful to the disk. The indicator assembly includes a wax which melts in a high-temperature environment and a hygroscopic salt which breaks down in a high-moisture condition. If either the wax or the salt changes from a solid form, a warning flag automatically moves into a position viewable to a cassette user.

Abstract: A cartridge comprises a rigid peripheral wall sandwiched between a pair of similarly rigid major surfaces, to form a compartment containing a disk arranged for rotation about a central axis. The cartridge obviates the need to have relative axial movement between the disk and a record/playback transducer head as the cartridge is loaded into a drive mechanism. To that end, a brake mechanism latches the disk axially, as well as radially, in its operative plane as the cartridge is loaded; additionally, the cartridge exposes the disk sufficiently to provide interference-free access to it by the transducer head. For that purpose, at least one of the major surfaces has a head-access opening extending to the peripheral wall, which, in turn, defines a relatively narrow bridge-like member, comparable in width to the operative plane of the disk, extending laterally, in the disk plane, from one side to the other side of the head-access opening.

Abstract: A defeat mechanism serves to prevent a floppy disk cassette from being operatively loaded into a drive mechanism when the cassette has been subjected to either a high-moisture or a high-temperature condition--either environment being potentially harmful to the recording capability of a floppy disk. The defeat mechanism includes a wax which melts in a high-temperature environment and a hygroscopic salt which breaks down in a high-moisture condition. If either the wax or the salt changes from a solid form, a control element of the defeat mechanism automatically moves into an actuated position which prevents the operative loading of the cassette.

Abstract: A copy protected magnetic storage disk includes a plurality of record tracks suitable for recording information-bearing data accompanied by a clock signal having a signal strength corresponding to the signal strength of the data. At least one of the record tracks includes a recording pattern representative of a code burst derived by temporarily changing the clock signal during a recording operation. Upon playback, the recording pattern of the code burst causes a random series of playback data to be produced which are dissimilar from one playback operation to the next playback operation. To verify the status of a disk (original or a copy), the code burst is read twice. With an original disk, the playback data is dissimilar; each time a copy is read, however, the same playback data is produced.

Abstract: A disk (magnetic, magneto-optical or optical) includes information-bearing tracks having prerecorded indicia, preferably tracking pads, distributed uniformly along each track for phase locking a write clock so as to write user data subsequently between the tracking pads, in the presence of random fluctuations in disk speed. The tracks are grouped into a plurality of annular zones encircling the center of the disk, wherein the ratio of the inner radius (or outer radius) of a given zone to the corresponding radius of the adjacent inner zone is a rational number, n/d, which is the same for each adjacent pair of zones. Each track within a given zone, i, has a fixed number of radially aligned tracking pads, P.sub.i, calculated from:P.sub.i =(n/d).sup.i-1 .times.(d).sup.N-1where i is 1 for the innermost zone and is N for the outermost zone.

Abstract: Rotary scanner apparatus includes a magnetic head on the periphery of a rotatable headwheel having a central axis of rotation, and an off-axis light source for projecting a collimated beam of information-bearing light obliquely onto a planar photodetector on the axis of the headwheel. To optimize electro-optical "action", and thereby enhance signal-to-noise ratio, optical apparatus, interposed between the light source and the photodetector, has an optical characteristic for shaping the light beam, to cuase the size and shape of its cross section, at a plane of incidence coinciding with the photodetector, to correspond substantially to the size and shape of the light-sensitive surface of the photodetector. Preferably, the optical apparatus includes a prism pair of performing anamorphic beam contraction, to convert the beam shape to circular, in its plane of incidence.