Abstract: A variable groove depth grating coupler located on a surface of an optical waveguide which couples a guided optical wave traveling in the optical waveguide to an outcoupled external wave has a resultant variable effective refractive index creating an aberration in the outcoupled optical wavefront. The wavefront aberration is corrected by providing the coupler grooves at a variable grating period which offsets effects of the variable effective refractive index on the wavefront aberrations.

Abstract: A programmable writing system for an optical disk drive which is adaptable for pulse position modulation (PPM) and pulse width modulation (PWM) pulse generation. The writing circuit is responsive to a PPM/PWM mode command for generating programmed laser pulse signals. Specifically, a pattern detector is responsive to the PPM/PWM mode command for detecting input data. The detected data is provided to a pulse selector for selecting programmed pulse power and/or duration values, which operate a pulse generator to set pulse power levels and/or to set the duration of the generated laser pulse signals. In PWM mode, the pattern detector provides a toggle signal with each detected signal and the pulse selector responds to the toggle signal to alternate between providing mark pulse power and/or duration values and providing space duration values to thereby provide alternating mark and space signals.

Abstract: Diagnostic apparatus and method are disclosed for testing a Small Computer System Interface (SCSI), by passively monitoring the interface between initiator and target devices or systems, upon sensing a user-selected phase of operation at the interface, disconnecting the initiator and target devices from one another, forcing a user-selected fault for the appropriate time, and reverting to a passive monitor. A pair of analog switches are provided for each line of the interface. The switches selectively connect the initiator system and the target system to each other or to a set of line drivers for providing high or low SCSI signals. A set of sense lines are connected to the initiator and the target for monitoring so as to sense the phase of operation of the initiator and target and to sense the response of the interface to the forced fault.

Abstract: Method and apparatus are disclosed for a data recording disk file having a head module with separate side by side read and write transducers for optimizing the switching of the head between reading information and writing information on the same track or cylinder. A function generator defines at least one control function for a servo control signal to drive an actuator to move the head module the approximate distance between the side by side write and read transducers, optimized to minimize the time between write and read, and optimized to move the head module the approximate distance between the side by side read and write transducers at the timing best suited to minimize the write transition time.

Abstract: Disclosed is a data recording disk file having multiple actuators mounted on a common pivot axis, one of the actuators having fewer arms and lower inertia characteristics than the other. A servo system separately drives each of the actuators for seek repositioning, the lower inertia actuator having a higher performance than the other. A controller selectively records one type of data on the data surfaces associated with the lower inertia actuator, and records all other data on the other data surfaces, thereby providing a disk drive with increased performance appropriate to the data stored on the surfaces associated with the lower inertia actuator. A removable locking pin may be provided which extends through corresponding holes in each of the actuators for maintaining the actuators precisely positioned with respect to each other so that servo information may be written on each of the surfaces in a single process.

Abstract: A disk drive system for both providing shock protection to the disk drive and reducing electromagnetic interference. A printed circuit board is provided having a shock sensitive device such as a disk drive and having electronic circuit components, e.g., data handling components capable of operating at a high data rate mounted thereon. The printed circuit board is provided with an electrical ground path and with at least one shock mount point. The shock mount point is provided with a conductive pad which is electrically connected to the electrical ground path of the printed circuit board. An electrically conductive carrier is provided for supporting the printed circuit board. At least one shock mount system is provided for attaching the printed circuit board to the carrier. The shock mount system comprises a shock mount grommet coated with an electrically conductive coating for electrically connecting the conductive pad to the carrier.

Abstract: A folding keyboard is described having keyboard sections, each bearing a subset of keys of the keyboard, and a slider mounted to one of the keyboard sections bearing a row of keys of the keyboard section, the slider movable between a first position withdrawn into the keyboard section behind a pivot axis so as to facilitate folding of the keyboard into a closed position, and a second position, corresponding with an open position of the keyboard, extended beyond the pivot axis to nest with a corresponding notch in the other keyboard section, so that the subset of keys of the slider are in a configuration for use when in the nested position. A key of each of the keyboard sections positioned at the abutting edges thereof are narrowed, from the standard width of other of said keys, along the edge thereof adjoining the abutting edges, so that the abutting edges are straight edges when the slider is in the withdrawn position, allowing a straight edge at the folding side of the keyboard.

Abstract: An improved MOS switched current mode drive circuit designed for use in systems interfacing multiple peripheral devices with one or more CPU units attached to a 360/370 channel.

Abstract: In magnetic heads it is often necessary to place conductive films on a ferrite substrate. If the ferrite is conductive, an insulative film is required between the ferrite substrate and the conductive film. A thin insulative film can be formed on a surface of the ferrite substrate by alternately dipping the substrate in solutions containing particles of silica and alumina.

Abstract: A copier-printer is employed in conjunction with an optical scanner and associated character recognition logic to transmit information contained in a document over a telephone line or other communication line. The copier-printer is used to make a copy of the document which is stored in the duplex tray. When a buffer memory associated with the communication line is ready to receive further information for transmission, the copy is retrieved from the duplex tray and circulated through the copier-printer to the optical scanner. The scanner provides the information from the copy to the buffer memory in a non-coded format except to the extent that the character recognition logic is able to code some or all of the information. The copy is advanced from the scanner to a mailbox in the form of a limited access compartment at the bottom of the collator for the copier-printer.

Abstract: A terminal connected to a data communication system and has an output device such as a printer or display and has a memory. The terminal stores the handshaking information received by the terminal from the data communication system as a communication session is established, translates the stored handshaking information into a suitable format for the output device, and supplies the translated data to the output device to inform the operator of the nature of the data communication system.

Abstract: Precisely positionable apparatus for collecting corona-generated current. A conductive sheet or coating is affixed to one side of an insulative sheet material. A low residue of nonresidue adhesive alone or carried by a tape is affixed to the other side of the insulative sheet. The sheet is then placed on a copier photoconductor or photoconductor carrier such as a drum, adhesive side to the carrier. The adhesive keeps the sheet flat against the surface at which the measurement is to be made. A shock protection line including front-to-back parallel diodes is connected between the conductive surface and ground. With the corona on, and the carrier in position, a current measuring device is connected between the conductive surface on a tab of the sheet and ground.

Abstract: An apparatus for and a novel method of collating, sorting and stacking sheets, concurrently termed "offset collation", are disclosed. The first sheets of sets to be collated, numbering up to the desired number of sets in a job, are transported from an entry station to a unitary bin sheet receiving station via a sheet transport station having an arcuate feed path to and through the aforementioned unitary bin sheet receiving station. These first sheets are stacked in the unitary bin sheet receiving station in an alternate offset fashion clearly demarcating the sets to be collated. The second sheets of the aforementioned sets are then sequentially inserted in the same alternate offset fashion contiguous to the first sheets. The method is repeated until all the sheets comprising a set have been inserted into all the sets. The final result is collated, sorted and stacked sets readied for convenient removal from the unitary bin sheet receiving station.

Abstract: A document feed mechanism for feeding original documents to a copier imaging station. A bottom feed shingler wheel generates a shingled stack of original documents in a tray having a crowned shape, the tray crest being located forward of the shingler wheel. The shingled stack is supplied to a nip formed by an intermittently operated feed roll and a restraint roll which is rearwardly biased via a magnetic hysteresis slip clutch. The normal force on a sheet in the nip and the rearward bias force of the restraint roll are specifically controlled. The feed and restraint rolls intermittently supply single sheets to an imaging station feed mechanism.

Abstract: A normal force applicator and removal apparatus which applies, varies and removes force applied to the top of a document stack where documents are being fed, i.e., by a shingler wheel type document feeder, (also termed combing wheel or wave generator) in order to generate a shingled stack of documents for subsequent processing. The shingler wheel is adjustable so that it can be centered for document stacks of multiple lengths. In order to shingle documents at a practical and predictable rate, i.e., maintain a shingled stack of documents, and to avoid skewing of the documents as they are shingled, the normal force is varied as a function of the thickness of the document stack decreasing as the document stack is depleted, and the normal force is applied symmetrically from the center of the shingler wheel to either side thereof. This symmetrical force distribution is maintained throughout the range of adjustment of the shingler wheel.

Abstract: A document feeder system, interfaced with a copier system having, inter alia, a semi-automatic document feeder (SADF), an automatic document feeder (ADF) a document queue, and an associated logic control system that allows the suspending of a prior task being run on either of the foregoing document feeders and the commencing of a subsequent or urgent task on any one of the other foregoing document feeders immediately thereafter. Thus, when an urgent task operator selects a feeder suspending/commencing mode button, a single control panel is instantly made available so that the urgent task copy quantity and feature selections can be made. After the foregoing is accomplished, the single copying of the prior task original document on the document viewing glass is completed and the document stored in the document queue or ejected into a prior task exit pocket. Then the chosen urgent task feeder is enabled for feeding.