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1953-54 Theatre Catalog, 11th Edition, Page 400 (362)

1953-54 Theatre Catalog, 11th Edition
1953-54 Theatre Catalog
1953-54 Theatre Catalog, 11th Edition, Page 400
Page 400

1953-54 Theatre Catalog, 11th Edition, Page 400

The Eidophor System

An Explanation of the Large Screen Color Television Process Developed by 20th-F OX

In the past few years there has been such a fiood of amazing technical advances made in the motion picture industry that there is a slight tendency to begin to take these developments :1 bit lightly. Just what has been the exact cause for this burst of technical achievement is difficult to determine. It might be the result of the pressure of television. The publicis demand for something new and exciting might be another cause. The pressure of economics might be still another answer. Regardless of the why of things, there is no doubt that the past five years has seen the arrival of more new developments of major importance than had appeared in the previous twenty-five.


One of the most exciting of these recent advances is a new system of projecting large-screen television pictures in full color, at high levels of lighting and contrast, and which is called Eidophor. The strange sounding name is derived from Greek, and consists of the word Eido, meaning image, and Phor, meaning bearer; hence image-bearer. Developed by a group of Swiss scientists, Twentieth Century-Fox holds the worldwide rights for the manufacture and distribution of projectors embodying Eidophor, and has adapted to it the Columbia Broadcasting Company% color process.

Simply defined, the system is a light valve capable of projecting video information on large screens at such contrast and light levels as may be required by the user. The outstanding advantages claimed for Eidophor are its ability to produce extremely high light outputs for projection of any required size, and its ability to display one or many colors as required for the single presentation of complex information or pictorial matter.


The Eidophor system is comprised of the projector in the theatre projection booth, a studio-theatre television remoting link, and color television cameras and synchronizing channels at the studio, together with associated sound equipment. The Eidophor projector was developed by a group of Swiss scientists of the Federal Institute of Technology and Doctor Edgar Griitener A. (L, of Zurich. The collaboration of' this group with the 20th Century-Fox technical staff under the direction of Earl I. Sponablo, and with color television of the Columbia Broadcasting Company and the General Electric Company, converted the original Swiss black and white equipment for full color projection.

Proiector Thc Eidophor projector is physically very much like a standard theatre motion

BRIEF: Before the current awakened . . . and feverish interest in three-dimensional and wide screen systems . . . 20th CenturyFox demonstrated a Swiss system of large screen color television which bore the strange sounding name of Eidophor . . . Based on a new and interesting principle . . . Eidophor . . . once it is offered to the theatres . . . seems like a perfect supplement to film entertainment.

This article discusses the background and development of the Eidophor method of color TV projection . . . as well as a section on the equipment required . . . and some possible future applications of the method.

picture projector in size, weight, and shape. It has the same type of controls for sound facilities and, in addition, employs a relay-rack cabinet housing the electronic circuits and controls. As in the standard moving picture projector, a carbon-arc light source is used, with appropriate projection lenses to magnify the televised image to the desired screen size.

In a moving picture projector a strip of film carrying a series of images is passed intermittently through the light beam, a shutter being provided to cut off the light while the film is traveling. In the Eidophor projector, instead of photographic images on a strip of film, a sequence of images is created on a thin layer of special liquid, about the consistency of honey, which is placed on a slowly rotating mirror surface in a


position optically equivalent to the position of the film in an ordinary projector. The succession of images on the thin liquid layer is produced by means of electrons deposited on the surface of the liquid; these electric charges are controlled by the television signal in much the same manner that a television signal is used to produce an image on a television picture tube.

The essential difference is that in the home receiver tube, the electron beam strikes the screen of the tube and causes the phosphor material to glow, point-bypoint, and line by line, with a brightness which is proportional to the point-bypoint brightness of the original scene. In the Eidophor system, however, the electron beam causes the Eidophor liquid to take on tiny surface irregularities and thus to change its optical properties; the picture so produced appears very much like the relief image in hardened gelatin used in some photographic processes. after the silver image has been bleached away. By means of auxiliary lenses and properly arranged mirrors, the instantaneous picture on this fiimage bearing" layer of liquid, is projected to the screen.

As noted, the Eidophor image is in a position "optically equivalent" to the position of the film in a standard projector. This point should be explained further. In the motion picture projector the center line of the light beam passes through the center of the picture being projected; and along the same straight line through the center of the lens to the center of the screen.

dramatically impressive and easy to view.

1953-54 Theatre Catalog, 11th Edition, Page 400