Abstract: A semiconductor-based, photo detector device capable of simultaneously detecting two or more selected wavelengths of light on a pixel-registered basis. The device has detector layers of selected semiconductor materials of one micron or less in thickness interspersed with contact layers, each detector layer having a different light absorption to wavelength response curve. All contact layers, including detector bias voltages, have electrical contacts on the backside of the pixel for discrete pixel connection to mating connections on a suitable ROIC substrate. Among its several embodiments, there is a multi-color detector array and a single channel per pixel differential optical signal detector.

Abstract: A method for alignment in software and supporting circuitry of the optical transmitters and receivers to their respective optical channels at each connection of a multi-channel optical link to an optical planar array, permits non-critical physical alignment of the connector to the optical array. The steps include: employing a connector and optical array configuration at each connection in which there are several optical devices within the illumination area of each channel at the connector/array interface, employing supporting circuitry and software that has control of all optical devices associated with the optical link, enabling all receivers, turning on the transmitters sequentially, recording which of the receivers is responding, comparing matching receiver sets for each transmitter to identify associated transmitter sets and channels.

Abstract: The present invention relates generally to a slide gate for use with an en-masse drag conveyor. The slide gate includes a frame adapted to be connected to the conveyor at a location adjacent to a discharge opening of the conveyor. The slide gate also includes a slide panel moveable between a closed position in which the panel is adapted to close the discharge opening, and an open position in which the panel is adapted to be retracted from the discharge opening. The slide gate further includes a moveable support structure adapted for supporting a chain of the conveyor. When the slide panel is moved to the open position, the support structure moves to a first position in which the support structure is adapted for supporting the chain as it traverses the discharge opening. When the panel is moved to the closed position, the support structure moves to a second position in which the support structure is located below the slide panel.

Abstract: A typical source of cadmium and tellurium is as a by-product of copper mining. Although attempts are made to remove impurities such as copper prior to commercially supplying them for forming material like cadmium telluride, cadmium zinc telluride and cadmium telluride selenide for use as a substrate to support electronic circuitry, processing during formation of the circuitry causes the impurities from the substrate to segregate into the circuitry, resulting in unacceptable electrical performance of the circuitry. A method for purifying the substrate prior to circuitry formation includes forming a sacrificial layer of mercury telluride or mercury cadmium telluride on the substrate, annealing the combination at elevated temperature with an overpressure of mercury and removing the sacrificial layer along with a contiguous portion of the substrate, if desired. The sacrificial layer may be formed by vapor phase type processes or even by liquid phase epitaxy.

Abstract: A brake drum includes a cylindrical braking drum having a flange end and an opened end and including a plurality of generally axially extending fins around an exterior surface thereof. Each of the fins has radially extending side walls which diverge along the length thereof from the opened end to a widest distance therebetween at a predetermined location from the opened end and converged along the length thereof from the predetermined location to the flange end. Accordingly, adjacent side walls of adjacent fins define a space therebetween which has its narrowest portion at the predetermined location. A steel band is secured to and encircles the braking drum at the predetermined location. The steel band cooperates with the adjacent side walls and the exterior surface of the braking drum to define a cooling air channel at the narrowest portion of each of the spaces.

Abstract: A method of forming a brake drum includes the steps of casting an iron cylindrical braking drum with a flange end and an opened end to include a plurality of generally axially extending fins around an exterior surface thereof. The casting includes providing the fins with radially extending side walls which diverge along a length thereof from the opened end to a widest distance therebetween at a predetermined location from the opened end and converge along the length thereof from the predetermined location to the flange end. Accordingly, adjacent side walls of adjacent fins define a space therebetween having its narrowest portion at the predetermined location. A braking surface is machined about an interior of the cylindrical braking drum. A top of the fins is machined at either side of the predetermined location to include a shoulder at the end thereof away from the opened end.