Abstract: A II-VI compound semiconductor laser diode includes a N-type GaAs substrate, a first cladding layer of N-type ZnSSe overlaying the substrate, a first guiding layer of N-type ZnSe semiconductor overlaying the first cladding layer. A quantum well layer of strained CdZnSe semiconductor overlaying the first guiding layer, a second guiding layer of p-type ZnSe semiconductor overlaying the quantum well layer, and a second cladding layer of p-type ZnSSe semiconductor overlaying the second guiding layer.

Abstract: A method for producing an ohmic contact to a p-type ZnSe semiconductor body in a molecular beam epitaxy chamber. Zinc, thermally cracked Se.sub.2 and nitrogen are injected into the chamber. A ZnSe contact layer is grown by heating the semiconductor body to a temperature less than 250.degree. C., but high enough to promote crystalline growth of the layer doped with nitrogen to a net acceptor concentration of at least 1.times.10.sup.18 cm.sup.-3.

Abstract: A receive magazine for collecting and transporting sheets of exposed photographic media. The receive magazine includes an elongated, light-tight enclosure having front and back walls, top and bottom walls, and first and second end walls. Sheets of media are gravity fed into the magazine entrance through a collection door on the top wall of the enclosure. The collection door includes a media-receiving slot, a shutter and a spring for biasing the shutter to a normally closed, light-tight position over the slot. A lower downwardly sloping resilient member mounted to the front wall engages the sheets as they are inserted into the magazine and forces the sheets into a vertically stacked arrangement against the back wall of the enclosure, away from the entrance. A ramp surface on the back wall guides sheets being inserted over previously collected sheets. A compound curved surface on the back wall of the enclosure below the ramp surface arcs the sheets to minimize contact during insertion.

Abstract: An exposure control apparatus for a microfilm printer includes an area (planar) light source, photo detector, and digital control circuits. An averaged density reading over at least the central five to twenty percent of the area of the microfilm frame is measured. This density reading is then used to control the intensity of the exposure lamp via a digital control circuit. The spatial relationships between the elements of the light source, the microfilm frame being read, and the photodetector are optimally arranged to provide an even illumination of the portion of the microfilm frame being measured without interfering with the film exposure process and without creating undue space demands.The microfilm density measurement provided by the apparatus is used to automatically control the intensity of the exposure lamp used in the exposure of a light sensitive medium in the development of prints from the microfilm.

Abstract: A semiconductor heterojunction, guided-wave, electroabsorption modulator. The device includes a rib waveguide fabricated on a substrate. The waveguide includes a relatively thin and off-center undoped electroabsorbing layer within a light-guiding region. Electrodes configured for interconnection to an external voltage source produce an electric field within the waveguide. Heavily doped field confining layers on opposite sides of the electroabsorbing layer confine the electric field within the electroabsorbing layer to cause the electroabsorption of radiation in accordance with the Franz-Keldysh effect.

Abstract: A thin film p-i-n solar cell and Schottky barrier diode are fabricated adjacent one another on a common flexible polyimide substrate. A titanium nitride diffusion barrier prevents contaminants of an aluminum contact layer on the substrate from reacting with the semiconductor body of the solar cell and diode during subsequent fabrication. An n.sup.+ -type hydrogenated amorphous silicon layer overlies the layer of titanium nitride, and forms an ohmic contact with the solar cell and diode. The diode includes an n-type layer of silicon doped with phosphorus to a concentration of 10.sup.18 to 10.sup.20 atoms per cubic centimeter to increase its forward current density. The solar cell and diode are separated from one another by an epoxy strip. A top conducting oxide layer forms a Schottky barrier with the semiconductor body of the diode.

Abstract: A multifocal ophthalmic lens includes first and second lens members. Each lens member has a smooth outer surface and an inner surface with an edge about its perimeter. A multifocal diffractive zone plate on at least one of the lens members is characterized by an index of refraction. The lens members are joined at the edges by ultrasonic welding to form a cavity adjacent the diffractive zone plate. The cavity is filled with a liquid medication having an index of refraction which is different than the index of refraction of the diffractive zone plate. A hole through one of the lens members functions as a fluid transport mechanism to permit transfer of the medication between the cavity and eye.

Abstract: A photographic media position sensing system for use in conjunction with a media processor of the type including a plurality of processing tanks for holding baths of conductive liquid media developing chemicals and a transport mechanism for driving the media through and between the processing tanks. The system includes a plurality of sensing electrodes, each of which is positioned adjacent to one of the processing tanks. One or more ground electrodes are positioned within the processing tanks for making electrical contact with the baths of developing chemicals. Media sensor circuits are connected between the ground electrodes and sensing electrodes. The media sensor circuits provide sensed media signals representative of the presence of media between the sensing electrode and adjacent processing chemical bath as a function of the capacitance between the sensing and ground electrodes.

Abstract: A developer replenishment control system for a continuous tone digital imaging system of the type including a laser imager for exposing pixels on sheets of photographic film as a function of digital exposure values representative of an image and a film processor with a developer replenishment mechanism for developing the imaged film. The replenishment control system includes lookup table memory and processing circuitry. Developer replenishment data in the form of an array of digital exposure values and corresponding incremental developed emulsion areal density values representative of the amount of developer required to develop the associated exposed film pixels is stored in the lookup table memory. The processing circuitry accesses the lookup table memory as a function of the digital exposure values to determine the associated incremental developed emulsion density values. The incremental developed emulsion density values for each sheet of imaged film are summed to generate replenishment control signals.

Abstract: A method for manufacturing an intraocular lens from a cell cast sheet of high molecular weight polymethylmethracrylate (PMMA). A lens blank having a lens generation area with a surface contoured to correspond to the desired contour of the finished lens is machined from the sheet of PMMA to a predetermined precompensated size larger than desired to acccommodate normalizing shrinkage. The lens blank is normalized by heating the blank in a vacuum oven. The vacuum is released from the oven by introducing dry nitrogen. A stamping die is provided. An optical embossing surface of the stamping die is contoured as a physical negative of the lens generation area and bears a physical negative of the desired optical surface structure of the lens, such as a multifocal diffractive zone plate. The embossing surface of the stamping die is forced into engagement with the surface of the lens blank at a predetermined stamping pressure and for a predetermined stamping dwell time.

Abstract: First and second hydrogel lens members are configured to be ultrasonically welded to one another. Both the first and second lens members have an annular bonding surface. The second lens member has an energy director extending from its bonding surface. The energy director has a generally rectangular cross section, a height of 0.127 to 0.178 millimeter, and an extended smooth surface of 0.127 to 0.381 millimeter width adapted to engage the bonding surface of the first lens member. The smooth extended surface of the energy director of the second lens member is mated with the bonding surface of the first lens member, and pressure in the range of 55.1 to 68.9 KN/m.sup.2 applied thereto to force the lens members together. Ultrasonic energy is applied to the lens members for a weld time period of 0.15 to 0.22 second. Following the weld period, the application of ultrasonic energy is discontinued for a hold time period of 0.15 to 0.25 second. The application of pressure is discontinued following the hold time period.

Abstract: An opening and closing mechanism for photographic film cartridges of the type having a film-receiving tray with outwardly extending front and side lips and a flexible cover for the tray resealably engaged with the lips. The opening and closing mechanism includes a cartridge-receiving base with front and side lips for supporting the front and side lips of the tray. A carriage is mounted for movement with respect to the base. An elongated roller including cartridge cover-engaging fingers is rotatably and movably mounted to the carriage. Springs bias the roller toward engagement with the lips of the base. A carriage drive assembly includes a roller drive linkage, a track drive linkage, a motor and a shuttle linkage. A rack is mounted adjacent to the base for engagement by the track drive linkage.

Abstract: A film densitometer for generating digital density values as a function of analog transmittance signals received at an input. A comparator coupled to the input compares the transmittance signals to one or more range references characterizing a plurality of ranges of transmittance signal magnitudes, and provides digital transmittance range signals as a function of the comparison. An amplifier amplifies the transmittance signals to provide amplified transmittance base signals. A gain control circuit coupled to the amplifier and the comparator controls the gain factor of the amplifier as a function of the magnitudes of the transmittance signals. The amplified transmittance base signals are converted to digital transmittance base values by an analog-to-digital converter. A lookup table of data characterizing the logarithmic relationship between transmittance base values and density base values is stored in base memory.

Abstract: A diffraction limited, f/6.0, 71.0 mm focal length telecentric scan lens which is color-corrected for 780 nm, 830 nm and 890 nm wavelengths. The lens includes, in succession from a side of incident light:a first negative meniscus lens element, concave toward the incident light side;a second positive meniscus lens element, concave toward the incident light side;a first plano-convex lens element, convex away from the incident light side;a second plano-convex lens element, convex toward the incident light side;a first cemented doublet including bi-concave and plano-convex lens elements, the cemented surface convex toward the incident light side; anda second cemented doublet including plano-concave and plano-convex lens elements, the cemented surface convex toward the incident light side.

Abstract: A film image reader/scanner apparatus providing two capabilities, operable at separate times wherein one capability provides for the projection onto a viewing screen of a light image created from a film image presented to the apparatus with the second capability providing for a line-by-line scan of the light image that is directed to a linear scan array for the production of signals representative of the light image.

Abstract: An improved temperature control circuit having a controller portion with an inhibit input and a temperature responsive circuit portion that includes a resistive portion connected in series with a sensor portion which establishes the control point for the control circuit, the improvement including a semiconductor switch in series with the sensor portion, the semiconductor switch having two electrodes between which a resistor is connected. The resistor is also connected to the inhibit input of the controller to present a signal to inhibit operation of the temperature control circuit when the sensor portion and semiconductor switch is not conducting.