The annual April Fool article by Mohammed Ulysses Fips in Radio-Electronics
described his invention of a three-dimensional TV. Fips explained:
Instead of a single electron gun, you have two, side by side. You also have two screens, one transparent. The picture of one gun therefore falls on the transparent screen, painting an electronic picture on it. The other gun throws another picture on the front screen. So you have two pictures, the same as you get in your eyes. One picture is superimposed on the other. One shows the necessary shadow; the other another picture which is supplemented by the other shadow, and if you now view the picture from the proper distance, the three-dimensional illusion is perfect.
This was the final April Fool article by Fips (aka Hugo Gernsback).