The caption on the photo says it all: Richard Thomas, the inventor, demonstrates his color lens mounted on a standard 35-mm. camera. By means of this lens, both movies and stills taken with ordinary film are reproduced in full color. Thomas used a set of lenses, "optical systems" to fold the path of the light, and four colored filters to produce four images in each frame of the film. He used red, green, blue, and violet filters. This produced four channels of gray images on panchromatic film. Projecting the film through a similar lens created a full-color image. The registration was exact because his lens system was built with an accuracy of .0001."
Besides full-color movies available only an hour after exposure, (because of the ease in developing black-and-white film) Thomas proposed using different filters in projection to analyse military photos. "...by changing filter combinations, certain colors may be held back and others accentuated, thus enabling the viewer to spot enemy installations that are invisible to the eye and to other color processes."