telegraphoscope

English

Etymology

telegraph +‎ -o- +‎ -scope

Noun

telegraphoscope (plural telegraphoscopes)

1. (historical) An instrument for telegraphically transmitting a picture and reproducing its image as a positive or negative. The transmitter includes a camera obscura and a row of minute selenium cells. The receiver includes an oscillograph, relay, equilibrator, and an induction coil whose sparks perforate a paper with tiny holes that form the image.