Abstract: A heterojunction diode laser which utilizes leaky wave coupling through a thin confining layer or a pair of thin confining layers to produce a high powered, highly collimated output beam with high external differential quantum efficiency, and relative freedom from facet damage resulting from high optical density.

Abstract: A phase-sensitive transducer apparatus comprises first and second relatively movable members, the first relatively movable member having a plurality of windings and the second relatively movable member having a winding. Means are included for applying a first input signal to one of the windings of the first relatively movable member and a second input signal to another of the windings of the first relatively movable member, an output signal being induced on the winding of the second relatively movable member. The first and second input signals are sinusoidal in nature of substantially identical frequency and peak amplitude and are phase-displaced by a predetermined amount, and the output signal is substantially constant in peak amplitude and variable in phase during relative movement of the first and second relatively movable members.

Abstract: In a computer peripheral device having a controllable element and control means coupled to the controllable element and operative in response to a power supply voltage of a predetermined level for controlling the controllable element, an improved power supply means coupled to the control means for supplying said power supply voltage to the control means. The improved power supply means comprises a motor capable of being driven at a predetermined rate of speed, means coupled to the motor and responsive to the motor being driven at the predetermined rate of speed for generating the power supply voltage, and means coupled to the means for generating for supplying the power supply voltage to the control means.

Abstract: A serial printer comprises a carriage, a print member rotatably mounted to the carriage and including a plurality of character elements, a drive coupled to the print member for rotating the print member to a desired rotational position, a device coupled to the print member for generating a plurality of periodic position signals each indicative of the rotational movement of the print member, and a device for storing a count indicative of the actual rotational position of the print member, the device for storing including a device responsive to an increment pulse for incrementing the count by one and a device responsive to a decrement pulse for decrementing the count by one.

Abstract: An analog chart recorder is provided having a heater assembly which includes a tapered, electrically resistive element that develops a non-uniform temperature profile on electrical energization along its length. A substrate is provided under the resistive film which is in thermal contact with the film. A heat sink in thermal contact with the substrate provides that the temperature distribution will achieve steady state. Means are provided for advancing a heat sensitive medium past and in contact with the heater assembly thus providing the analog chart recorder.

Abstract: A head assembly for magnetic recorders includes a mounting bracket designed for increased rigidity. Releasably attached to the mounting bracket are two head carriages, each having affixed thereon a magnetic recording and reproducing head. The heads are positioned such that as the mounting bracket moves radially with respect to two recording discs, each head is individually precisely radially positionable with respect to any recording track defined on its respective disc.

Abstract: A matrix print head comprises stylus guide means; a plurality of electromagnetic structures coupled to the guide means, each of the electromagnetic structures including a pole piece; a plurality of armatures disposed radially about the guide means, each of the armatures being associated with one of the electromagnetic structures to form an electromagnetic actuator for transferring electromechanical energy to a stylus, and each of the armatures having an inner end and an outer end projecting outwardly of the associated pole piece; a plurality of styli respectively associated with the plurality of armatures, each stylus being carried by the guide means and having an armature engaging end for engaging the inner end of the associated armature and a printing end for impacting a record medium when the stylus is propelled through the guide means by energization of the associated electromagnetic actuator; and an improved armature retainer coupled to the guide means for maintaining each armature in engagement with its

Abstract: Method and apparatus for expanding the number of grey scale values in a digital flying-spot scanning system. The scanned recording medium is divided into a plurality of unit cells, each of which is assigned a desired grey scale value, and each unit cell is further divided into a plurality of subcells formed by a plurality of adjacent portions of scan lines comprising digitally controlled segments. The grey scale value of the unit cell is dependent upon the portion of the subcells within the unit cell which are activated or deactivated by the scanning beam. Additionally, the number of grey scale values between particular numbers of activated subcells is expanded by providing varying patterns of predetermined numbers of subcells within the unit cell with the varying patterns producing the optical effect of varying grey scale levels.

Abstract: A linear actuator for selectively moving a carriage relative to a support frame along a predefined linear path.

Abstract: A carriage assembly for transporting a print member along a predetermined path adjacent a support member comprises a first carriage section adapted to be mounted adjacent the support member for movement along the predetermined path, apparatus for mounting a print member to the first carriage section for movement between first and second positions relative to the support member, and apparatus coupled to the mounting apparatus for retaining a print member mounted to the frame in each of its first and second positions. The retaining apparatus includes a biasing member for biasing the print member in a direction opposite its second position when at its first position and in a direction opposite its first position when at its second position. The biasing member preferably includes an over-center tensioned spring coupled between the first carriage section and the mounting apparatus.

Abstract: An electrically pumped distributed feedback grating coupled diode laser having an optical cavity containing two closely spaced layers, a first of the layers is electrically pumped and the second of the layers is corrugated. Optical wavelength radiation and amplification of said radiation is generated in the first layer by carrier recombination with the radiation spreading to the second layer for coherent reflection by the corrugation and for low loss transmission. Carrier confinement in the first layer and optical confinement in the optical cavity are achieved by surrounding each of these layers by materials having a higher bandgap and lower index of refraction than the materials of the first and the second layers. The corrugation of the second layer can extend over only a portion of the length of the second layer such that the uncorrugated portion of the second layer provides a low loss waveguide.

Abstract: Recording machine such as electrostatic printer/plotter or facsimile plotter includes housing construction and associated operating components whereby overall external width reduction is accomplished without loss of function using liftable lid and method of cross-bracing. Machine serviceable through removable bottom closure panel supporting an electronic chassis. Operating stations, such as recording assembly including both electrostatic latent image recording station and a toner developing station, and web-cutting assembly each includes portions in both lid and base of housing to be yieldingly held together in cooperating relation by hinged latching panel in which the hinge pin supplies spring action to urge and retain the latching panel in its detented position.

Abstract: Record material feed apparatus for use with a printing machine of the type including a platen, means for rotating the platen about its axis, at least one roller, a lever capable of manual movement between first and second positions, and means coupled between the lever and the roller for maintaining the roller in engagement with the platen when the lever is in its first position and for maintaining the roller spaced a predetermined distance from the platen when the lever is in its second position.

Abstract: A hammer assembly comprising a housing having opposing open ends and an internal passage extending between the open ends. A hammer element is positioned in the housing for reciprocal movement in the passage between first and second positions. The hammer element has an opening formed therein in which a biasing member is positioned. When enabled, the biasing member is capable of biasing the hammer element in a desired direction relative to the first and second positions. Means are also included for enabling the biasing member when the hammer element is in at least its first position. The housing is desirably fabricated of a self-lubricating material with the area of the opening at one of its ends substantially larger than the cross-sectional area of the hammer element, taken along a plane perpendicular to the axis of motion of the hammer element at such one end in order for air to be freely vented from the passage during reciprocal movement of the hammer assembly.

Abstract: A serial printer comprises a carriage, a print member rotatably mounted to the carriage and including a plurality of character elements of a predetermined font style, drive means coupled to the print member for rotating the print member to a desired rotational position in order to place a selected character element at a printing position adjacent a record medium to be printed upon, print hammer means mounted to the carriage and capable when enabled of impacting the character element located at such printing position with a desired level of force, and hammer control apparatus coupled to the print hammer means for enabling the print hammer means when the selected character element has been rotated to the desired rotational position.

Abstract: A read/write apparatus for magnetic recorders including a decoder for converting input digital control and data signals into a plurality of select signals, a voltage source switchably connected to the read/write heads of the apparatus such that individual select lines are enabled for determining which recording head is actuated for writing on a chosen magnetic medium, what orientation of magnetic flux will be written, and what magnitude of flux will be written. Also, the select lines operate, when the voltage source is disabled, to condition the heads to allow read-out of data recorded on the magnetic media, and to select which head is to perform this read-out. Also included in the recorder is a signal redigitizer to digitize data read from the magnetic media, and erase means for reducing edge and transient effects on the magnetic media.

Abstract: An optical display comprised of an array of small focusable image elements in conjuction with a corresponding array of optical stops or filters, one optical stop or filter being aligned with each image element. Upon the application of a force field to selected ones of the image elements, the optical focal point of those image elements is changed to thereby allow ambient light incident upon those image elements to be focused differently than it was prior to the application of the electric field whereby the optical stops aligned with the selected image elements intercept a different portion of the ambient light reflected or transmitted the selected image elements than do the optical stops aligned with non-selected image elements to thereby provide a display having light and dark areas.

Abstract: A flying spot scanning system is provided by utilizing reflected light from a multifaceted rotating polygon which is then directed to the scanned medium. A light source illuminates at least two contiguous facets of the polygon during each scanning cycle, to provide the desired sequence of spot scanning. To assure a uniform spot size at the scanned medium, an optical convolution of elements is selected in combination with the light source such that an adequate depth of focus at the medium is assured. In each scanning cycle, information is transmitted to the scanned medium by modulating the light from the light source in accordance with a video signal.

Abstract: A method of making a buried-heterostructure (BH) diode injection laser capable of operating at low room temperature thresholds and in the lowest order TE, TM, or TEM modes. Following formation of a pump current confining layer in a substrate, an elongated groove or channel is formed in the substrate with the groove extending through the pump current confining layer. A first light guiding and carrier confining layer, an active layer, and a second light guiding and carrier confining layer are then grown successively on the grooved surface of the substrate with the active layer material having both a higher index of refraction and lower bandgap than the material(s) of the light guiding and carrier confining layers.

Abstract: A pin wheel feeding device includes a housing capable of being rotated about an axis. A plurality of substantially identical pins are disposed within the housing in respective alignment with a plurality of openings. Each pin includes a pair of opposing guide members. A cam member disposed within the housing is capable of being fixed in position relative to the housing. The cam member has a track formed thereon with which each of the pins is engaged with the pair of guide members thereof being located on either side of the track. The width of the track at first, second and third segments thereof is substantially coextensive with the locus of points traced by the closest adjacent points on the pair of guide members of each pin during movement of the pins along the first, second and third segments of the track.