Abstract: Disclosed are systems and techniques for image generation applicable in general to any long persistence display device, particularly one in which contrast builds over a number of frames. The display device disclosed in detail by way of example herein is a high resolution cathodochromic CRT (CCRT) in a projection system. The system includes a deflection generator for the display device capable of writing to at least individual image lines in any order and, in some embodiments, to individually-addressed pixels. In raster-scanned embodiments, an image memory is included, capable of storing pixel data on a line-by-line basis. An image controller serves to read particular lines from the image memory and to write corresponding image lines on the display device. In one embodiment, those scan lines which have no picture information (e.g.

Abstract: Disclosed are systems and techniques for alignment of CRT-based display systems, particularly those employing a high resolution cathodochromic projection CRT. The disclosed techniques permit all major CRT-related alignment to be performed at a factory or other centralized facility, with automatic precision alignment in the field of the overall display system, including a CRT assembly as one element. A replaceable, standardized CRT subsystem includes a CRT assembly, itself subject to sample variations, and a non-volatile personality memory, such as an EEPROM, having stored parameters specifically applicable to the CRT assembly on an individual basis. The CRT assembly has no field adjustable parts, but does include elements for electron beam control, such as electromagnetic coils for focus and deflection permanently affixed to the CRT. Thus at the factory, a skilled operator having appropriate equipment available performs an electronic alignment procedure with reference to a particular CRT.

Abstract: An improved method for erasure of an image target in a CCRT projection system includes the steps of projecting a defocused electron beam onto the target forming a scan line, establishing an energy level below the erase threshold to prevent erasure of any portion of the target within the single line, scanning multiple lines across the full target, and overlapping the scan lines sufficiently to provide integrated heat energy to cause erasure. The energy level is established at about 75% of the erase threshold or about 0.3 joule/cm.sup.2. The power is preferably set at 30 kv and 400 microamps with a single scan line being established at 0.056 inch. Preferably, the scan line is set to overlap 5-12 times to cause erasure, with the optimum being approximately 8 overlaps. In the related CCRT set up of the erasure mode, after overlapping the scan lines, the energy level is gradually increased until the integrated heat energy is sufficient to cause erasure.

Abstract: An elongate elastomeric seal member including a first portion to be partially received in an elongate groove of a selected element where the groove has opposite sides and a base connecting the sides and a second portion extending outwardly from the opposite edges of the groove to sealably engage a sealing surface adjacent the element where fluid pressure is selectively applied to at least one side of the seal and where the seal, in cross section, includes a central body with first and second spaced feet extending outwardly therefrom to be received in the groove and engage the sides and base of the groove and third and fourth feet extending outwardly from the central element to slidably engage the sealing surface wherein fluid can be applied to at least one of the third and fourth feet to urge one of said third and fourth feet to sealing relation with said sealing surface.

Abstract: A monitor for a vapor compression refrigerant system using halocarbon refrigerants that accumulates contaminant gases present or generated in an operating system and provides a readout indicative of the presence of significant amounts of contaminant gases which readout serves to provide an indication of an incipient malfunction of the refrigerant system. Embodiments of the monitor are disclosed which provide continuous and automatice purging of the contaminant gases from the system using perm-selective membranes with or without provision for providing indicia of the presence or build-up of contaminant gases in the monitor.

Abstract: A sheet metal attachment system and method for the installation of underground mine brattices of the type in which a gas impervious barrier of malleable sheet metal is retained on a peripheral framework of slotted beams. The fastening system involves pre-mounting a plurality of bolts projecting from one face of the framework as piercing pins so that the sheet metal may be initially applied by forcing it over the pins. The pierced sheet metal is then drawn against the framework by a multi-apertured washer plate and barrier mounting nut threaded onto the bolts.