Abstract: A beam feedback synchronization system for optical sweeping apparatuses is disclosed. The system includes a multi-faceted rotating reflection mirror which acts on a collimated light beam such as a laser beam to cause it to sweep periodically in parallel straight lines across a rotating photoconducting drum. A portion of the light beam is split off and caused to sweep across an equispaced linear array of fiber optic apertures held in place by a fiber optic assembly. The light entering the fiber optic apertures is carried along fiber optic elements to one or more photodetectors which generate periodic electrical signals in response thereto. The frequency of occurrence of the electrical signals from the photodetector is a measure of the velocity of the sweeping light beam across the fiber optic array.

Abstract: The present invention comprises a low gain amplification circuit for amplifying the output of a light detecting transistor and producing a logic outputstrong enough to drive standard transistor logic circuitry. One or more bipolar non-symmetrical transistors are arranged in a cascade connected circuit to produce an amplification gain less than that of a single conventional transistor. The bipolar non-symmetrical transistors are reverse connected between the high level and low levels of the power supply and all feedback lines are eliminated while the frequency response is substantially increased.

Abstract: A graphic forms overlay apparatus to be used with non-impact printers requiring the use of a movable light sensitive medium such as laser printers is disclosed. Laser printers use a sweeping laser beam and a movable light sensitive medium to image data from a data processing source for printing. A graphic forms pattern is overlayed on the data imaged on the light sensitive medium for simultaneous printing of the data and pattern. To accomplish this a negative of the pattern is mounted on a hollow rotatable forms drum, and inside the drum a fluorescent tube is fixedly mounted for illuminating the negative. A linear portion of the light image of the negative formed thereby is reflected by an optical system of lenses and mirrors onto adjacent linear portions of the light sensitive medium being swept by the laser beam for imaging of data.

Abstract: A crossed light beam position indicator includes orthogonal arrays of paired light emitters and detectors for covering a display surface with crossed light beams, scanning means coupled to the emitters and detectors for electronically scanning the orthogonal arrays such that a single emitter at any one time is emitting light. Improved scanning means include means for scanning the detector associated with a particular emitter and in addition scanning one or more adjacent detectors during the time that a single emitter is activated to provide plural light paths from a single emitter and thus more precisely define the position of an object placed in proximity to the display surface.

Abstract: A light emitting source and a light sensing device are permanently fixed on one side of a moving object substantially separated one from the other. The light rays from the source are bent or reflected in a predetermined path so that the light rays to be sensed passes through at least two holes in said moving object before being sensed, thus enhancing the light to dark ratio and reducing the probability of false readings.

Abstract: The present invention switch comprises a pair of electrodes separated by resilient resistive material which changes resistance several orders of magnitude in response to light pressure. Sensing and amplifying means are provided to detect a predetermined change in resistance. An array of a plurality of such switches may be arranged in a switching matrix to provide any desired form of switch controls or a keyboard for numerous electronic applications.

Abstract: The present invention comprises selectively locating electrical shorting rings on the male section of an optical cable connector. The particular locations of the rings chosen is commensurate with the length of the cable and provides a basis for amplifying the signals being transmitted along the optical cable. On the female section of the cable connector there are electrical contact devices which can be shorted by the rings on the male section if such rings are present. There is a selectable amplifier circuit connected to the optical cable and the contact devices, and depending upon which contact devices are shorted the amplifier circuit provides the proper amplification to the optical signals which are being converted into electrical signals.

Abstract: A memory system which already includes an address register, a randomly accessible memory unit, a data-in register and a data-out register is converted to also include a one word buffer memory with the addition of only a few components. A plus one adder is included for incrementing the address contained in the address register and the result is then stored in an address plus one register. The randomly accessible memory unit may be accessed with the address plus one register when it has completed the normal access with the address register pending a new request. The resultant memory data from this access at the incremented address is stored in a one word internal register which is a buffer to the randomly accessible memory unit. Since such access is noninterfering with and overlapped in time with the overall memory system communication with a requestor, and pending any new request to the randomly accessible memory stores, it serves to efficiently create a buffer store only for the next consecutive address.

Abstract: A method of and apparatus for optimizing the data transfer rate from a dynamic storage subsystem to an asynchronously clocked requestor using a variable rate oscillator and a first-in-first-out or FIFO buffer. On writing data into the dynamic storage subsystem, data is transferred from the requestor to the FIFO buffer and the variable rate oscillator clocks the data from the FIFO buffer into the dynamic storage subsystem at some relatively slow rate. If the FIFO buffer begins to fill, the frequency of the variable rate oscillator increases causing data to be clocked from the FIFO buffer at a higher rate. On reading data from the dynamic storage subsystem, the variable rate oscillator begins at a maximum frequency clocking data into the FIFO buffer from where it is transferred to the requestor. If the FIFO buffer beings to fill up, the frequency of the variable rate oscillator is decreased.

Abstract: Apparatus for sensing marks on a moving paper object includes light source means for transmitting light through a portion of a partially opaque mark and into the translucent fibers of a paper object. Light detecting means are provided for sensing the relative amount of light transmitted into said fibers by detecting the light in said fibers under said mark at an area transversely disposed from the portion of the mark where the light was applied.

Abstract: An electromagnetic linear actuator for positioning a transducer over locations on a rotating magnetic recording disk comprising an actuator housing used as a stationary base for supporting various parts; a coil and cart assembly including a cart, having a rectangular cross section and tubular in construction, adapted at one end to support the transducer, and including a direct current coil with a cross section matching that of the cart mounted at the other end thereof; magnetic means affixed to the actuator housing having an air gap for receiving the coil so that the coil is immersed in a magnetic field; and support means affixed to the actuator housing engaging the surfaces of the cart and disposed about the center of gravity of a moving-mass assembly consisting of the coil and cart assembly and the transducer.

Abstract: A mechanism in a computer system translates a program-generated virtual address into a real address of at least a portion, such as a byte, of a segment of the storage of the computer system. The translation mechanism is operable in either of two modes for forming the real storage address. In either mode of operation of the translation mechanism, a first portion of the virtual address is utilized to select a predetermined one of a plurality of segment descriptors, each having a first field portion and a second field portion.

Abstract: Apparatus for distributing evenly delayed digital signals to a plurality of separate physical locations in which each location utilizes one particular digital signal. At each physical location an apparatus for adjusting the timing delay of the digital signal is provided so that all physical locations may utilize the digital signals, as for example, a pulse from a timing chain, at the same instant of time with respect to each other. The apparatus for adjusting the timing delay at each location includes a receiver for accepting the digital signal. After the receiver, the digital signal is routed to both a delay line capable of providing a plurality of time delays and to a selector having an input for the received digital signal and for each one of the time delays provided by the delay line. Finally, each selector provides a means of selecting just one of the signals to be utilized at that physical location.

Abstract: An apparatus for and a method of parallelizing the conjugate deflected light beams of a magneto-optic light deflector system. The apparatus includes two converging half-lenses, the centers of which are removed. The two converging half-lenses are oriented superposed with their centers aligned along the center of the light beam that is directed normally incident to the plane of the magneto-optic light deflector. A converging lens is oriented in the optic axes of the parallelized conjugate light beams for focusing the two parallelized conjugate light beams upon a screen or detector.

Abstract: The present invention is a method and apparatus for passive generation of magnetic bubbles in thin layers of magnetic materials, such as garnets, and uses specially designed permalloy elements which with the rotation of an in-plane magnetic field act to generate magnetic bubbles over a wide range of bias magnetic field values. The design of a special permalloy element includes an angular portion and a contiguous remaining portion having a large surface area relative to the angular portion. Pulsing of the in-plane rotating field to higher field values as it passes through a predetermined orientation with respect to the angular portion generates magnetic bubbles in a controllable manner for fixed values of the bias field.

Abstract: An apparatus for and a method of utilizing a magneto-optic stripe domain light deflector for both the transmitted and received light beam.

Abstract: A block replicate bubble memory device is provided with a plurality of series storage loops, wherein data words are written into or read out of the storage loops in parallel. The data is entered into write lines and is read on to read lines which are connected to the series storage loops approximately one-half of one loop time apart. Information in the storage loops is ordinarily changed or altered in no less than one-half of one loop time in the prior art. The present invention provides a plurality of bubble generators connected to the serial write line in a manner which permits several bubble device functions to be conducted in less than one-half of one loop time.

Abstract: A method of and apparatus for determining the gel point of a sample of epoxy resin. An aluminum foil tube containing the sample is inserted into the test pressure sensor which is located within a preheated laboratory environmental chamber. The test pressure sensor consists of two knurled cylinders each rotatably mounted about its axis wherein the axes are parallel and the plane of the two axes is horizontal. The axis of one of the cylinders is fixedly mounted. The axis of the other cylinder is slidably mounted within the horizontal plane of the two axes. A spring tends to force the axis of the slidably mounted cylinder toward the axis of the fixedly mounted cylinder. The sample becomes liquid within the tube, and the two are drawn into the nip of the cylinders by their rotation. The cylinders continue to rotate collapsing the sample tube within the nip of the cylinders causing the liquid resin to be displaced above the nip of the cylinders within the sample tube.

Abstract: A method of and an apparatus for differentiating between hard and soft failures of semiconductor memory cells for the purpose of error logging only hard failures. A spare bit position is appended to each addressable location within the semiconductor memory. The spare bit position is set, if the corresponding addressable location is observed to contain a single bit error during regeneration. The spare bit position is cleared, if the corresponding addressable location is observed not to contain a single bit error during regeneration. An error log entry is made for normal read access to an addressable location observed to contain a single bit error only if the spare bit is set indicating that a single bit error was present during regeneration of that addressable location.

Abstract: Inverter power supply control circuitry that protects power supply components from relatively quick-changing over-current conditions and that provides regulation of the power supply's output current upon relatively slow-changing load conditions.