Abstract: An adjustable mounting assembly for ceiling fixtures has a pair of opposingly spaced apart mounting brackets (12,14) for mounting onto respective ones of a pair of spaced apart ceiling joists (20,22). The mounting brackets (12,14) include apertures (28,30) which receive therebetween a telescopic tube (16) comprising a first tubular member (32) and a second tubular member (34) being slidably received within the first tubular member (32). The first and second tubular members (32,34) are movable in opposing axial directions between a retracted position and an extended position to suit a distance between the ceiling joists (20,22). The telescopic tube (16) has mounted thereon a carrier bracket (18) which is adapted to move axially along the telescopic tube (16). The carrier bracket (18) includes a downwardly facing aperture (50) and axial movement of the carrier bracket (18) along the telescopic tube (16) allows the downwardly facing aperture (50) to align with the desired position of the fixture on the ceiling.

Abstract: A system for effecting precision laser surgery includes an intensified surgical video microscope directed at the tissue to be operated upon and having zoom capability. The surgical microscope presents a microscopic image on a video screen in front of the surgeon. Preferably, the video screen is divided into multiple separate sections, with the microscopic video image in one section and precise cross sectional and plan views indicating location presented in the other sections of the screen. These additional views may be generated using Moire interferometry by projecting a Ronchi ruling on the surface of the tissue, in viewing the projection with a camera to obtain all necessary information for contour tracking of the subject surface. Interior elements and interfaces of, for example, the eye are also sensed by a light beam and precisely located and mapped by a computer forming a part of the device.