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New DirectVision Stereo-Projection Screen
By W. WHEELER JENNINGS and PIERRE VANET
This paper discusses the development of a new direct-vision stereo-projection screen. It permits the audience to see three-dimensional color motion pictures and slides without the aid of conventional polarized viewing glasses.
J? OR MORE THAN half a century, thousands of dollars have been invested by researchers in the hope of developing a good commercial free-vision stereoprojection screen. The problems encountered have been very complex.
First, let us re-examine the mechanism of our visual impressions. We see objects in relief because of the perception of each of our eyes of a point located in space and observed at different angles that correspond to the distance between the eyes (Fig. 1). The convergent action of our eyes enables us to estimate by exploration the various distances of different points located in space.
The image received on the retina of the right eye is not the same as received by the left eye. In order to get the impression of relief, it is necessary to project two views taken at different angles and to avail oneself of means that will enable each eye to see only the
Presented on April 22, 1952, at the Society's Convention at Chicago, 111., by W. Wheeler Jennings, 7549 South Clyde Ave., Chicago 49, 111., and Pierre Vanet, Societe des Anciens Etablissements, A. Mattey, Paris, France.
picture it should receive at the exclusion of the other.1
In order to get natural binocular vision under our existing stereo-projection processes, it is necessary for the spectator to wear special polarized or red and green viewing spectacles.
We will deal here only with the processes of stereo projection that give us directly and collectively three-dimensional screen images as seen with our natural vision.
The Noaillon Theory
In 1928, Professor Noaillon, of Brussels, Belgium, developed a selector system, made up of radial converging lines in the form of grills with very wide openings. This system consists of three reclining grills shaking or oscillating in their own plane around their meeting points, as shown in Fig. 2.
Figure 3 shows projection on screen E through this radial-lined network which determines the selective vision surfaces. Starting from the stereo-projector G and D, representing the left and right stereo images, the projected image travels to the meeting point O
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July 1952 Journal of the SMPTE Vol. 59