The history of lenticular printing - barrier method

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An autostereoscopic display presents a three-dimensional image to a viewer without the need for special glasses or other impediments (hence "auto" stereo). The first autostereoscopic method to appear was the "barrier" technique, which involved dividing two or more pictures into "stripes" and aligning them behind a series of vertically aligned "opaque bars" of the same frequency. It was first proposed and demonstrated by the French painter G. A. Bois-Clair in 1692. As a viewer walked by his paintings, they would appear to change from one picture to another.

The barrier technique was later proposed using photographic methods independently by both Jacobson and Berthier around 1896. It was first applied by Frederick E. Ives of the U.S. in 1903 and later by Estenave of France in 1906. Coined the "Parallax Stereogram" by Ives, it was essentially a stereo viewing aid placed on the picture instead of at the eyes.

Figure 1. The Parallax Stereogram, as patented by
Fredrick E. Ives in 1903.

Besides the Parallax Stereogram, Frederick E. Ives (1856-1937) is also credited for inventing novel approaches to color photography, color "moving" pictures, and the half-tone process that made the publication of photographs in newspapers and magazines possible.

Figure 2. The anatomy of a Parallax Barrier. (Roberts, 1992)

The Parallax Stereogram (Figure 1 and 2.) was made up of three elements: (1) a barrier-masking screen, which consisted of vertical opaque lines, separated by clear slits of lesser width. (2) A transparent glass plate behind the barrier screen which created spacing between it and (3) the photographic emulsion that consisted of the picture information divided into fine mosaic image stripes aligned behind each clear aperture.

They were made by separately projecting the left and right-eye stereo views through the barrier screen, from precise angles, so as to divide them into narrow vertical image stripes positioned alternately side by side. When the photographic plate was developed and reinstated behind the same barrier screen, the viewer's left-eye would see only the left-eye mosaic stripes and the right-eye would see only the right-eye stripes (see Figure 3). If a fine pitched barrier screen is used, the screen becomes nearly transparent and each eye would see its own corresponding image stripes as a whole composite image, thus receiving the two dissimilar views necessary to realize a three-dimensional impression.

Figure 3. Sight lines though a Parallax Barrier Screen. (Roberts, 1992)

Researchers at the Soviet Motion Picture and Photography Research Institute (NIKFI), including S.P. Ivanof, further investigated the concept in the early forties. They constructed a large radial, non-parallel-type barrier screen to project "parallax stereogram" motion pictures. The screen reportedly weighed several tons and required a dedicated theater with specially positioned seating to view.