Vacuum tube, Philco Flat-faced Developmental CRT

While electronic television was under development in the late 1930s, various manufacturers worked to perfect different elements of the system. This early kinescope (picture tube) is shown with its focusing coil, deflection yoke, and beam bender. It was constructed by John Vansant in Philco's laboratories in Philadelphia, and incorporates several improvements on existing kinescopes, including a patented electron gun trap to eliminate the dark spot which typically appeared at the center of early television picture tubes.