Abstract: A display device that includes a display medium having a planar display area over which an image is generated, a first and second optical point beam each directed in the display medium coplanar with the planar display area, and beam controllers that scan each of the optical point beams to selectively interfere in the display area within a region defined by the intersection of the optical point beams to produce an intensity in the region that has enhanced visibility relative to the individual optical beams propagating in the display medium outside of the region. The beam controller may be an elongated reflector having a reflecting surface upon which a linear array of liquid crystal modulators are controlled to selectively transmit segments of a linear beam incident on the linear array, in order to provide the optical beam by selectively reflecting segments of the linear optical beam into the display medium.

Abstract: The invention generally relates to an improved flotation apparatus and process for purifying a stream of effluent by forming a separable, buoyant floc out of waste matter suspended in the effluent. The improved process and apparatus utilizes a tank for containing an effluent, a skimming means for skimming the buoyant floc out of the tank, and a floc barrier and current diverting means including an inclined, buoyant top wall which is pivotally mounted on the sides of the flotation tank, and a bottom wall having a top edge which is adjacent to the bottom edge of the top wall. The upper portion of the buoyant top wall prevents floc from straying from the floc accumulation region of the tank over to the outlet region of the tank, while the lower portion of the top wall, working in conjunction with the bottom wall, diverts fluid currents which tend to float floc over to the outlet region of the tank.

Abstract: This invention generally relates to an improved flotation apparatus and process for purifying a stream of effluent by forming a separable, buoyant floc out of the waste matter suspended in the effluent. The improved apparatus and process utilizes a mixing and floc dispersion means for intimately admixing the stream of effluent with a conditioning agent in a stream of tiny gas bubbles. The mixing and floc dispersion means also functions to dampen floc-sinking currents which are generated by the introduction of the stream of effluent into the flotation tank, and to uniformly disperse the resulting floc across the width of the tank. The mixing and floc dispersion means includes a series of at least two elongated, fluidly connected chambers, wherein the second chamber has a larger cross-sectional area than the first chamber.