Abstract: A stereoscopic television/video system which provides true stereoscopic imaging without the use of glasses or other viewer encumbrances, and which is compatible with current storage, processing, pick-up, and broadcasting equipment as well as standard band-widths and formats, produces a composite video signal containing two images, which signal when received and displayed on a video display screen produces a manifestation containing two horizontally-disparate views of an object scene. Positioned at one of a set of mathematically defined loci in front of the video screen is a transparency consisting in vertically-oriented elements of two types: active elements which deviate light paths from the video screen, and passive elements which transmit light paths from the video screen to the viewer without deviation.

Abstract: An instrument for use in ophthalmic surgery to retract the iris and provide optimal dilation of the pupil in a facile, atraumatic, and thoroughly controllable fashion. The instrument includes a pair of curved retracting tips adapted to engage the iris gently and positively for expanding the pupil to permit removal of the crystalline lens without injury to the iris. The retracting tips are mounted on a pair of cross-action spring arms and the instrument is designed for easy comfortable one-hand operation.