Abstract: An apparatus is provided for varying the direction which a control laser beam impinges on a rotatable storage medium. The reflected control beam is thus modulated by surfaces aspects of the medium such as by embedded reference tracks. This reflected light signal is converted to an electrical signal which is analyzable to determine vertical alignment particularly with respect to the orthognal direction. In one embodiment, the apparatus comprises a rotating cylinder in which a lens is disposed in a canted orientation so that the optical axis of the lens is not exactly aligned with the axis of the cylinder about which rotation occurs.

Abstract: Laser light is focused in an accurate manner on selected tracks on an optical disk recording medium by means of an analysis of output electrical signals from a dithered light source which results in the production of an electrical signal which is proportional to an amount by which the light source in the system is to be moved, relative to the tracks, in order to achieve desired tracking of the focused spot along a desired track on the medium.

Abstract: In a system for writing a plurality of information tracks between adjacent portions of a reference track on a rotatable medium, advantage is taken of the fact that laser beam dithering a cross an edge of a reference track produces signals which are analyzable to determine much more exact radial positions. A pattern of bits is written on the medium with a known spacing between bits. This may be at the time of disk manufacture or later. As these bits are being read, a clock is started along with a bit counter. At this time, a precise determination is made of the radial position at which the read bits are present. From these values, angular and/or linear velocities are computed and stored on the medium. Collected over time, this information is useful for determining aging characteristics of the drive mechanism for the medium.

Abstract: A method for writing information on a laser writable recording blank with reference tracks utilizes a split laser beam. A first of these beams is used for writing while the second is directed to a mirror or similar device which causes the second beam to move across a track edge in an oscillatory manner. The laser light reflected in this process is converted to an electrical signal which is analyzed to determine very precisely the distance between the track edge and the point of impingement of the first beam on the disk. Power in this first beam is then controlled so as to write information on the disk. The precise control allows a plurality of information tracks to be written between adjacent reference track portions.

Abstract: In a system for writing a plurality of information tracks between adjacent portions of a reference track on a rotatable medium, advantage is taken of the fact that laser beam dithering a cross an edge of a reference track produces signals which are analyzable to determine much more exact radial positions. Reading of a certain number, N, of bits during a known period of time, T, permits the determination of the linear or angular velocity of the disk. Knowledge of this value permits its much more precise control.

Abstract: A laser beam is split into two beams. One beam is oscillatorily at a first frequency in a direction associated with control of beam focus within two or more layers of a rotatable information storage medium, that is, in a CD-ROM-like device. The second beam is oscillatorily varied at a second (different) frequency in a direction so that it moves back and forth across an edge of a reference track. Separate filters are used to examine the reflected light so as to simultaneously control positioning of the laser light source a long two axes.

Abstract: In a system for writing a plurality of information tracks between adjacent portions of a reference track on a rotatable medium, advantage is taken of the fact that laser beam dithering a cross an edge of a reference track produces signals which are analyzable to determine much more exact radial positions. Once a value for radial position is determined, a precise measurement of linear velocity is determined for bits moving past a read/write head. As a reference point passes under a read/write head, a clock is started. The value from the clock, the radial position and linear velocity are used to provide an indication of either distance along a track as measured from the reference point or, alternatively, to provide an indication of angular position, also as measured from the reference point.

Abstract: A method is provided for reading an information track, or a writable disk with reference tracks, almost immediately after the information track has been written. Precise control of the positioning of the laser source which provides the parallel beams for writing and reading, is accomplished by analysis of the electrical signal produced by a reference beam reflected from an edge of a reference track on the disk/medium. Oscillatory movement of this beam across a track edge produces the desired electrical signal for precise position determination, and hence, for precise position control.

Abstract: A photodetector and a threshold detector are employed to determine from which side (left or right) of an embedded track light is being reflected from. This information is encoded in the light signal reflected from a rotatable storage medium by oscillatorily moving a laser beam back and forth across an edge of the embedded track. A waveform detector provides a signal, based on the output of the photodetector, which provides an indication of distance away from the edge of a subject track. The output of the threshold detector and waveform detector drive an up-down counter which thus associates a unique binary number with each information track.

Abstract: A method is provided for determining, and thus controlling, vertical alignment of a laser beam used to read and/or write data from or to a rotatable information storage medium, such as a CD-ROM or CD-ROM-like disk. For a period of time, light from the laser is made to impinge on the medium from slightly different directions. The reflected light is analyzed using frequency doubling principles to determine when the light beam is most nearly perpendicular to the medium.

Abstract: An apparatus is provided for reading an information track, on a writable disk with reference tracks, almost immediately after the information track has been written. Precise control of the positioning of the laser source, which provides the parallel beams for writing and reading, is accomplished by an analysis of the electrical signal produced by a reference beam reflected from an edge of a reference track on the disk/medium. Oscillatory movement of this beam across a track edge produces the desired electrical signal for precise position determination and, hence, for position control.

Abstract: An apparatus for controlling the positioning of a laser light source for reading and writing information on a form of recording blank with reference tracks utilizes the edges of the reference tracks. A laser source has its beam split in two parts. A first of these beams is used for writing, while the second of these beams is directed to a track edge across which it is moved in an oscillatory fashion by a mirror. The light reflected from the track is converted into an electrical signal which is analyzed to provide an indication of the position of the laser light source with respect to the track edge used.

Abstract: An apparatus for reading and writing information on a laser writable rotatable storage medium employs a single laser source. Part of the laser beam is diverted and made to move in an oscillatory manner across an edge of an embedded track. The other portion of the beam is used for reading and writing. To avoid overloading reading detector circuits, an enable switch is provided which responds to read/write control signals.

Abstract: A laser-writable information storage blank comprises a substantially planar disk made of a material which is susceptible to modification by impingement of laser radiation. The blank medium includes a metallic track pattern, preferably in the form of a spiral pattern. The track pattern provides two reference edges from which exact distances may be determined for writing and reading binary information stored between adjacent track portions.

Abstract: An information storage system employs rotatable disks with embedded tracks for precise control of writing and reading operations. Advantage is taken of the reference tracks on one of the disks to also control laser spot positioning on the other side of the disk. The edges of the reference tracks are employed to assure accurate positioning and the presence of multiple information tracks between adjacent reference tracks.

Abstract: A system for reading from and writing on rotatable information media includes embedded reference tracks whose edges are used for precise information track positioning and also for precise laser source positioning. The nature of the returned signal is such that it can be used for monitoring the aging characteristics of the laser light source. Maximum and minimum values are gathered over time and stored in any convenient non-volatile storage device, even the disk itself.

Abstract: A laser beam is split into two beams. One beam is oscillatorily at a first frequency in a direction associated with control of beam focus within two or more layers of a rotatable information storage medium, that is, in a CD-ROM-like device. The second beam is oscillatorily varied at a second (different) frequency in a direction so that it moves back and forth across an edge of a reference track. Separate filters are used to examine the reflected light so as to simultaneously control positioning of the laser light source along two axes.

Abstract: A laser beam is split into two beams. One beam is oscillatorily varied at a first frequency in a direction associated with control of beam focus within two or more layers of a rotatable information storage medium. The second beam is oscillatorily varied at a second (different) frequency in a direction so that it moves back and forth across an edge of a reference track. In the embodiment herein both beams, after reflection from the medium, are returned to the laser source which is also used as a photodetector. Separate filters are used to examine the electrical output of the photodetector/source so as to simultaneously control positioning of the laser light source along the axes.

Abstract: Advantage is taken of a laser beam and reference track system for recording information on a CD-ROM or similar device. Precise determination of radial and angular position provide accurate indications of drive motor speed and performance, both instantly and over any select period of time so as to give an early indication of motor or bearing wear or failure.

Abstract: A pluggable connector capable of connecting a large number of electrical transmission lines per connector, and small enough to enable a large number of connectors to be added to a multi-chip module. For example, 5 or 6 of these connectors can add over a hundred coaxial cables to a module. Improved I/O communications is added to a module by such coaxial cables, since they can communicate very high frequency signals in noise prone environments. The pluggable connector is embedded in a multilayer module (e.g. ceramic or glass) for conveying digital information to transmission lines internal or printed on the surface of a module. Each connector contains a receptacle 19 having a silicon contact structure embedded in an edge of a multi-chip module. The contact structure is formed with a plug-receiving angle for deflecting multiple cantilevered plug contacts 17 into engagement with corresponding receptacle contacts 22.