Abstract: A GaP photodiode having a shallow PN junction and an internal directed surface electric field exhibits high quantum efficiency in detecting ultraviolet wavelengths.

Abstract: An improved method of determining the energy bandgap of an epitaxial semiconductor layer on a substrate corrects for an overestimation of energy gap yielded by normal optical transmittance measurements. The overestimation of energy bandgap is caused by a graded bandgap region which exists between the epitaxial semiconductor layer and the substrate.

Abstract: An automatic photographic paper cutter includes a print and order totalizer system which stores information such as the number of prints cut and the number of orders which have been processed by the paper cutter. In one operating mode, the totalizer system counts the number of prints cut in each order. At the end of an order, the number of prints cut in that order is displayed and is maintained on the display until the next order is completed. This allows the operator time to record the number of prints in the previous order while the next order is being cut. In another mode, the totalizer system displays the total number of prints cut and total number of orders since operation of the paper cutter commenced. This information is particularly useful to management since it permits an accurate determination of the performance of both the automatic paper cutter and the particular operator of the cutter.

Abstract: A compact inexpensive dryer unit for photographic processors which includes a liquid removing squeegee unit, transport rollers and guiding means for moving photographic sheet material through the drying area, a pair of opposed tapered air distribution manifolds to uniformly distribute warm drying air against both sides of the sheet material in close proximity thereto as it travels through the dryer with provision for recirculating substantial portions of the warmed air after it travels through the drying area of the unit, one of said manifolds being hinged to facilitate access to said drying area for servicing.

Abstract: A photographic print sorting, conveying and packing mechanism includes a main conveyor line and a plurality of branch conveyor lines with an initial feeding device which receives individual cut prints from a print cutter and feeds the prints into the main conveyor line which defines a main flow path. All of the conveyor lines include a plurality of driver rollers spaced apart less than the length of each cut photograph so that one roller will always be in contact with the prints to maintain positive driving contact with the prints at all times during their successive travel along the conveyor lines. The conveyor lines also include deflecting elements ahead of each roller to flatten momentarily the curl in each print and insure proper driving engagement between the rollers and the print.

Abstract: A knife assembly capable of cutting photographic strip material with high accuracy at extremely high speeds includes a base, a stationary blade, a source of rotary power, a crank shaft, a spring-wrap clutch mechanism, first and second linear drive shafts, first and second adjustable linear bearings, and a movable blade. The spring-wrap clutch is mounted on the crank shaft for selectively imparting rotary power to the crank shaft, and the first and second linear drive shafts are connected to the drive shaft. The movable blade is connected between the ends of the first and second linear drive shafts.

Abstract: An aperture stop is provided near the detector imaging lens of a thermal imaging system to prevent the infrared detector from viewing portions of the thermal imaging system itself, particularly the walls of the optical housing and the housing of the scanner within the optical housing. This eliminates "shading" problems which can occur in thermal imaging systems having a moving scanner within the optical housing.

Abstract: A film advancement system for use in a photographic film cutter includes a movable cursor which indicates, by its position, a desired feed length. A cursor position sensor senses the position of the movable cursor with respect to a reference position and provides a feed length signal indicative of the feed length desired. The film is advanced by a distance determined by the feed length signal.

Abstract: An automatic photographic paper cutter includes a drive system which drives a strip of photographic paper to a knife assembly. The drive mechanism applies a driving force along only one edge of the photographic paper strip, so that the operator of the paper cutter has an essentially unobstructed view of the prints on the photographic paper strip. A paper supply, which includes a spring loaded bale arm assembly, a pinch roller drive assembly, a brake, a motor and clutch, two loop sensors, and a U-shaped wire form guide supplies the photographic paper strip from a roll of photographic paper to the drive mechanism under essentially zero drag conditions.

Abstract: An improved method for providing electrical connection to a photodetector in a Dewar flask is disclosed. A plurality of conductive paths are formed on the inner flask of the Dewar. Each of the conductive paths extends from the side surface on to the top surface of the inner flask. A photodetector having lead tabs is mounted to the top surface of the inner flask with the lead tabs aligned with the conductive paths. The lead tabs are bonded to the conductive paths to provide electrical connection to the photodetector.

Abstract: An automatic replenisher system for photographic processors has an improved, digital electronic control. The control includes sensors and signal processing circuitry which provide a signal having a frequency indicative of a measured parameter (such as film density or film transport speed) which is associated with the operation of the processor. A counter counts in response to the variable frequency signal. The counter is interrogated at predetermined intervals, and an energizing signal is produced. The energizing signal has a time duration which is determined by the count in the counter at the time of interrogation.

Abstract: An improved method for providing electrical conductive paths in a Dewar flask is disclosed. A thin metal film is deposited over the side and top of the inner flask of the Dewar. Portions of the metal film are then selectively removed to provide electrical conductive paths which extend from the side on to the top of the inner flask.

Abstract: A mercury cadmium telluride semiconductor device includes an epitaxial layer of mercury cadmium telluride on a first substrate. A silicone rubber adhesive layer bonds the first substrate to a second substrate.

Abstract: A dielectric waveguide oscillator includes a microwave producing diode, a strip resonator, and a dielectric waveguide butted against one end of the strip resonator.

Abstract: An electromagnetic radiation detector has a first surface which receives incident electromagnetic radiation. The sides of the detector are sloped such that incident radiation does not initially strike the sides.

Abstract: Pyroelectric detectors are mounted on a substrate having a plurality of wax-filled cavities. The wax is then dissolved to provide a low thermal loss mounting structure for the detectors.

Abstract: Graded composition protective layers are prepared for water soluble optical elements. The two materials forming the graded composition protective layer are vapor deposited in the presence of a third vapor which does not react or co-deposit with the two materials. The third vapor inhibits decomposition of one of the two materials by reducing the vapor temperature of the other material.

Abstract: An interval timer for use in traffic control, industrial process control, or other interval timing applications includes a gated pulse generator.

Abstract: An improved method for providing electrical connection to a photodetector in a Dewar flask is disclosed. A plurality of conductive paths are formed on the inner flask of the Dewar. Each of the conductive paths extends from the side surface on to the top surface of the inner flask. A photodetector having lead tabs is mounted to the top surface of the inner flask with the lead tabs aligned with the conductive paths. The lead tabs are bonded to the conductive paths to provide electrical connection to the photodetector.

Abstract: PN junctions in mercury cadmium telluride are formed by implantation of gold ions and a subsequent low temperature--short duration heat treatment.