Monday, Jul. 08, 1929

Colored Television

Bell Telephone's Dr. Herbert Eugene Ives, 47, disclosed last week his progress with colored television. He has spent his life on photography, photoengraving, light, colors, sending pictures by electricity and, lately, television. He had a direct technical antecedent. His father, Frederic Eugene Ives, 73, invented a process of colored photography and the halftone process of photoengraving.

Colored television has become possible because Dr. Ives's colleagues at Bell Telephone laboratories invented a photo-electric cell more sensitive to light than the usual cell. The usual cell depends on the ionic action of potassium and hydrogen. The new cell uses sodium with sulphur vapor and oxygen.

The Ives colored television apparatus contains a battery of 24 cells. A filter or "mash" of orange-red gelatin allows only reddish colors to affect certain cells. A yellow-green filter controls other cells, and a greenish-blue filter controls the balance. Three separate electrical transmission channels must be used. A red gelatin filter makes the bright red neon light the same shade as the receiving cell registered. The yellow-green-sensitized waves go to an argon lamp which glows through a green filter. The greenish-blue-sensitized waves affect another argon lamp with, in this case, a blue filter. Mirrors focus the fluctuating glows of all three receiving lamps on a single spot and as that spot rapidly weaves across a peephole, an observer perceives a scene in all its moving naturalness.