5,821,989 - Stereoscopic 3-D viewing system and glasses having electrooptical shutters controlled by control signals produced us

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Abstract
The present invention relates to a system and method of viewing pairs of perspective images of 3-D objects (i.e. stereoscopic image pairs) displayed from a CRT display surface in a time-multiplexed or field-sequential manner, and more particularly to a universal method of generating control signals for synchronously changing the optical state of liquid crystal (LC) shutter panels through which the time-multiplexed perspective images can be sequentially viewed in a substantially flicker-free manner by the left and right eyes of a human viewer, independent of whether the images are displayed on NTSC, PAL, VGA or SVGA styled CRT display devices.