Eastman-Kodak Company

Charles J Simpson

Philip F Marino

Kurt W Getreuer

James A Barnard

Boris A Shtipelman

Paul D Heppner

Richard H Martens

Gerald A Lange

An optical disk for high speed data recording and playback is disclosed. The optical disk includes a stiffening layer having two spaced-apart surfaces, the stiffening layer having a specific stiffness selected to be greater than 1*10.sup.8 inches and being positioned at the center of the thickness of the optical disk. The optical disk further includes first and second recording layers, each recording layer being formed over opposite surfaces of the stiffening layer, and first and second substrates being formed over the first and second recording layers, respectively.

Optical disk for high speed data recording and playback

An optical actuator adapted to control the position of the actuator in at least two degrees of freedom of motion. The actuator includes a base, a moveable lens holder having a lens, a structure for connecting the lens holder to the base to support movement of the lens holder, and first and second pairs of surface-field motors, each pair of surface-field motors having first and second surface-field motors, each first and second surface-field motor including a surface-field coil and a surface-field magnetic assembly for applying forces to the lens holder to move the lens holder in at least two degrees of freedom of motion relative to the base, the surface-field coil being mounted on either the base or the lens holder, and the corresponding surface-field magnetic assembly being oppositely mounted on either the lens holder or the base to interact with the surface-field coil. Each surface-field magnetic assembly includes two pairs of opposing poles with one pair of opposing poles facing the corresponding surface-field coil, the opposing poles of each pair being separated by a pole dividing line so that the pole dividing lines of the opposing poles facing the surface-field coils of the surface-field magnetic assemblies of the first surface-field motor extend and intersect at a point above the surface-field coils, and the pole dividing lines of the opposing poles facing the surface-field coils of the surface-field magnetic assemblies of the second surface-field motor extend and intersect at a point below the surface-field coils. Currents are selectively applied to the surface-field coils so that the surface-field motors apply forces to the lens holder to control at least two degrees of freedom of motion of the lens holder relative to the base.

Multiple degrees of freedom actuator for optical recording

An optical disc is disclosed having a substrate in which data can be written on or read from, such optical disc has a transparent cover sheet which is held at a desired spacing from the substrate at least at an inner radius and an outer radius. In order to prevent the transparent cover sheet from deflecting due to pressure differences between the outside atmosphere and the air in the space between the substrate surface and the transparent cover sheet, a plurality of air passages in the transparent cover sheet are provided near an inflection point where on one lateral side of the point the transparent sheet will bulge and on the other lateral side it will be depressed due to centrifugal force acting upon air entrapped between the transparent cover sheet and the substrate surface during disc rotation in an optical disc drive. This arrangement equalizes the pressure in the air space between the transparent cover sheet and the substrate surface and the outside atmosphere.

Optical discs with cover sheets and pressure equalization of the

A lens actuator for an optical disc storage device including a base; a lens holder assembly movably mounted to said base; said lens holder assembly comprising a lens holder with a single surface-field magnet and a lens mounted thereon; a single surface-field coil set mounted to said base parallel to and proximate said surface-field magnet; whereby a current introduced in a coil of said coil set produces a net magnetic force having a resultant line of action passing through said lens holder assembly.

Actuator with single surface-field motor

An optical actuator is disclosed which includes a base, a moveable lens holder including an objective lens and positioned relative to the base, and at least six planar magnetic coils and a plurality of magnetic assemblies arranged to be associated with the coils, each of the assemblies including magnets having two or more poles fixed to the actuator base, the coils and the magnets being mounted relative to each other on the lens holder and the base. The actuator includes circuitry for applying signals to the coils to induce magnetic fields in the coils for positioning the lens holder and detectors for providing signals representing the four degrees of freedom of positions of the lens holder with respect to the base. A computational circuitry responsive to the detectors determines the coil signals for positioning the moveable lens holder in six degrees of freedom of motion relative to the base.

Magnetically suspended optical recording actuator

An optical recording actuator is disclosed and includes a base and a moveable actuator lens holder having its position controlled between two to six degrees of freedom of motion. Such lens holder including an objective lens. The actuator further includes a sensing system a light source and three sensors and mounted on the moveable lens holder three separate plates, each corresponding to a sensor and having an aperture and arranged so that light from the source passes through the aperture of each plate and illuminates its corresponding sensor mounted on the base. Each sensor includes an arrangement for providing position detection in two orthogonal directions and a microprocessor responsive to the position detection to determine the position of the moveable lens holder with respect to the base in six degrees of freedom of motion.

Position sensing for an optical recording actuator

A combined sensor for measuring tilt and tracking position of a lens holder with respect to an optical recording actuator base is disclosed. A light source and two photosensitive bi-cell detectors are secured to the actuator base so that a beam from the light source strikes the detectors, and an optical slot or flag is secured to the lens holder between the light source and the detectors, for creating an image on the bi-cell detectors. Output from the bi-cell detectors is converted into information on tilt and position of the lens holder relative to the actuator base.

Combined tracking position and tilt sensor for optical recording actuator

An optical reading or writing actuator for directing a laser beam for reading or writing an optical medium including a base and an actuator assembly having an objective lens fixed in the assembly and flexures for supporting the actuator assembly for movement in focus and tracking directions to position the objective lens. The actuator further includes at least one sensor disposed relative to the actuator assembly for producing an output tracking position signal and a beam splitter positioned relative to the actuator assembly and the sensor for directing a portion of the laser beam to the sensor and for directing another portion of the laser beam to the objective lens which focuses it on the optical medium.

Beam splitter for optical reading and writing actuator

An instant film unit, including first and second superposed sheets, and conventional internal spacers for controlling the depth of a layer of processing fluid distributed by flowing the fluid between the sheets, is provided with additional internal spacers that reduce the resistance to fluid flow and augment the quantity of fluid supplied to the lateral edges of the imaging area. In the disclosure, the first spacers comprise portions of a mask, which frames the imaging area. The additional spacers are side rails which separate the lateral edges of the sheets by an amount greater than the thickness of the mask. The film unit is adapted for use with a processing device which includes a pressure nip long enough to span the imaging area, but the side rails are outside of the pressure nip adjacent the ends thereof.

Instant film unit

A preregistered, instant-processing film unit including an internal dark slide removeable from an end section of the unit and a light seal for preventing daylight fogging of the unit from said end section. The film unit includes a photosensitive element for recording a processable latent image. A cover sheet is connected to the photosensitive element and the dark slide is removeably positioned between the element and sheet. The light seal includes a strip coupled to the photosensitive element and folded into the dark slide so that the strip is released by the act of removing the dark slide.

Growing community of inventors

Rochester, NY, United States of America

Charles J Simpson