Abstract: An optical reading apparatus for moving a mirror in a back and forth motion such that the mirror scans the light reflected from an optical pattern and sequentially projects narrow segments of the reflected image onto a linear image sensor. Moving the mirror includes means for mounting the mirror within a movable case which is mounted on a shaft to selectively cause the case to go back and forth in a seesaw-like fashion. As the case goes back and forth, it causes the mirror to sweep or scan across the reflected image of an optical pattern. As the mirror sweeps across the reflected image of the optical pattern it sequentially projects different segments of the optical pattern onto the linear image sensor until the entire optical pattern is projected onto the linear image sensor. The linear image sensor is operable at a high rate of speed and is sufficiently sensitive that it can sense numerous (e.g., 50, or more) segments of the reflected image during one sweep of the mirror.

Abstract: Two filter sections having different frequency responses are interconnected via selectively enabled switches, formed on the same integrated circuit (IC) as the filter sections, between a signal input terminal and a signal output terminal. The selectively enabled switches can be used to: (a) selectively connect the two filter sections in cascade between the signal input and output terminals to produce a bandpass filter; or (b) selectively connect the two filter sections in parallel to produce a notch filter, or (c) couple only one of the two filter sections between the signal input and output terminals; or (d) provide a short circuit between the signal input and output terminals. In a preferred embodiment the filter sections are switched capacitor filters. The filter system of the invention is highly suited for use in an engine knock signal processor integrated circuit.

Abstract: An optical image sensor, particularly a bar code reader, comprises a laser diode emitting a light beam of small area and elliptical cross-section. The light beam is directed onto an optical device for greatly expanding the beam along one axis for expanding the beam cross-section to that of a greatly elongated rectangle having a line-like shape. The line beam is projected from the reader for encompassing and illuminating the entire width of a bar code. Light reflected from the bar code is focused as a complete image of the bar code onto a light detector for simultaneous storage of all the bar code data. The beam expander can comprise a cylindrical lens, a cylindrical mirror, or a conical mirror including means for varying the intercept of the laser beam with the conical surface for selectively varying the width of the expanded beam.

Abstract: An EPROM cell comprises an MOS device including a floating gate electrode overlying, and ohmically insulated from, the channel region of the MOS device, and a separate diode including a p-n junction having a substrate surface intercept. A floating gate electrode overlies the diode p-n junction intercept and is ohmically isolated therefrom by an intervening insulating layer. Writing of data into the floating gate electrode of the MOS device is achieved by causing a voltage breakdown across the diode p-n junction and the flow of high energy electrons across the junction. A voltage is simultaneously applied to the diode gate electrode thereby attracting some of the high energy electrons through the overlying insulating layer into the diode floating gate electrode. The diode gate electrode is ohmically connected to the MOS floating gate electrode on which some of the electrons are stored for affecting the turn-on, turn-off characteristics of the MOS device.

Abstract: An autocollimator having particular utility in optical aiming systems for the cannons of battle tanks comprises a pair of light sources for directing two beams of light along different paths towards a light reflector mounted, for example, on the muzzle of a tank barrel. The two beams of light are thus reflected along different paths towards a position sensitive light detector suitable for providing an output electrical signal indicative of both the receipt thereon of one or both of the reflected light beams and the position of the light beams on the light detector. The light sources are alternately turned on and off in non-overlapping time periods to provide identification of which of the two beams is being detected by the light detector.

Abstract: In an optical reader a lens system is located between a source of light designed to illuminate an object to be read and the object. The lens system is designed to refract and diffuse the light produced by the light source to reduce the deleterious effect of specular light reflected from the illuminated object into the optical reader and an image sensor designed to convert reflected photo signals into electric analog signals. In one embodiment of the invention the optical reader includes an array of LEDs and a lens having prisms located in front of each LED for refracting or bending the light output of each LED to reduce the generation of specular light being reflected. In another embodiment the optical reader includes a lens with a light shield strip to prevent the generation of specular light.

Abstract: Apparatus for illuminating a bar code at a relatively shallow (i.e., acute) angle, and for sensing the light reflected from the surface at the shallow angle. In one embodiment the apparatus is used to illuminate the data bars at an acute angle along their length. Viewing the illuminated area at an acute angle, equal to the acute angle of incidence, increases the area being viewed and tends to spatially integrate the non-uniformity of the data bars. Apparatus embodying the invention is particularly useful for reading bar codes formed on a highly reflective surface. The shallow angle of illumination increases the contrast between the surrounding surface and the "data bars" of the bar code as it increases the effective area being viewed and enables the bar code to be read more accurately. In some embodiments a laser light spot is swept at an acute angle across a bar code and the light reflected from the bar code is viewed at the acute angle.

Abstract: First and second resistors are connected in series with a Zener diode between first and second points of operating potential. The base-to-emitter of an NPN transistor is connected across the first resistor to sense the current through the series path. The collector-to-emitter of a PNP transistor is connected across the second transistor, whereby when the PNP transistor is turned-on hard and into saturation, the voltage drop across the second transistor decreases. The collector of the NPN transistor is connected to the base of the PNP transistor, whereby when an overvoltage condition exists and the Zener diode breaks down, the two transistors are driven regeneratively and form a latch and the operating point of the circuit is shifted.

Abstract: A mechanism for providing a conventional drill with an automatic screw feeding capability comprises an elongated sleeve formed from a tubular wall defining an elongated passageway, a screw driving rod slidably and rotatably disposed within the passageway, and a dependent, hollow skirt surrounding an opening through the wall providing access to the passageway. A magazine containing a spring urged stack of screws, each disposed within a stacking cylinder, is inserted into the skirt for disposing a top end of the magazine within the passageway. The magazine top end includes a slot in alignment with the rod axis allowing removal of a cylinder jacketed screw from the magazine by the rod upon forward movement thereof. In use, the rod rear end is engaged within a drill chuck and movement of the rod relative to the sleeve is obtained by relative movement between the drill, held in one hand by a user, and the sleeve mounted magazine, held in the user's other hand.

Abstract: A screwdriver for alternative use with Phillip head screws and slotted head screws is disclosed comprising a handle and a shank extending therefrom, the leading end of the shank terminating in a Phillips head screw engaging bit. The leading end portion of the shank is bifurcated by a rearwardly extending slot, and an elongated blade tipped with a slotted head screw bit is slidingly disposed along the slot. The blade is provided with a series of gear teeth along each edge and a nut is mounted around the shank for engagement with the blade teeth. The nut maintains the blade within the slot, and rotation of the nut controls the axial positioning of the blade to positions either forwardly or rearwardly of the Phillips bit.

Abstract: A digital to analog converter including an R-2R ladder network receives digitally encoded sample signals in parallel through a set of chains of transistor switches, each chain having equal delay. The ladder network output impedance matches the characteristic impedance of a coaxial cable transmission line that couples the converter output to a utilization circuit. Output resistances of the switches which are connected to ladder network rung circuits are scaled in accordance with a predetermined algorithm to maintain symmetry of parallel connected resistive branches of the latter network seen at each rail terminal of the ladder. Three of the most significant bits of each input binary coded work are decoded to a bar code format before being coupled through the set of switch chains.

Abstract: A binary tree is created from flat part list and synonym output files and a component library. Each tree record includes a part, type, full path name, and net functional description for each primary net of each block and for each component in that block. The hierarchical coupling of these records and the primary net descriptions in each record supply all of the information necessary to extract a hierarchical net list.

Abstract: A binary adder stage in which the two binary inputs are logically combined to produce the Exclusive-OR, the Exclusive-NOR, the NAND and the NOR functions of the two inputs. The carry-input signal is then used to control the generation of the sum output and the carry-output. When the carry-input signal has one binary value, the Exclusive-OR function and the AND function of the binary inputs are produced at the SUM and C.sub.OUT outputs. When the carry-input signal has the other binary value the Exclusive-NOR function and the OR function of the two binary inputs are produced at the SUM and C.sub.OUT outputs.

Abstract: A network for preventing large transient currents in the conduction paths of a pull-up transistor connected between a first point of operating potential and an output point and a pull-down transistor connected between the output point and a second point of operating potential. The network includes a third transistor having its base to emitter path connected in parallel with the base to emitter path of the pull-down transistor and its collector coupled to the base of the pull-up transistor. The collector current of the third transistor is limited, causing it to saturate at a given current level and to then limit the flow of additional base drive to the pull-down transistor, whereby the maximum collector current of the pull-down transistor is also limited. In addition, a diode is connected between the output point and the collector of the third transistor.