Direct-view three-dimensional display tube

The three-dimensional display tube is a novel type of cathode-ray tube that directly displays volumetric analog information. In contrast to other presentations in which the third dimension is simulated stereoscopically or with color, this device displays the information in actual space. The three-dimensional display tube utilizes a phosphor coated disc spinning at 900 rpm within an evacuated sphere. Upon excitation by a cathode-ray beam at selected times, any point in the volume "swept out" by the rotating disc may be illuminated at 30 cps. The result is true volumetric analog display, which is visible without any special viewing position or glasses. Thus, minimum observer fatigue and equal display resolution in depth are possible as compared with existing stereoscopic three-dimensional displays. Different color phosphors on either side of the disc and appropriate cathode-ray beam gating provide a simple means of two color display. Also, special deflection scans that are compatible with particular display requirements can result in a display equal in brightness and quality to commercial television display. Some typical applications as well as the technical aspects of this type of display such as brightness, data storage requirements, and feed circuit bandwidths are discussed. Compatibility with normal observer vision and ease of determining target intersections within the display volume are important properties of this type of display.