John Logie Baird demonstrates the world's first television system to transmit live, moving images in tone graduations, to 40 members of the Royal Institution. The 30-line images are scanned mechanically by a disk with a spiral of lenses at 12.5 images per second.
Japanese researcher Kenjiro Takayanagi demonstrates a system that uses a mechanical Nipkow disk and a photoelectric tube in the transmitting device, and a cathode ray tube in the receiving device. He transmits the 40-line still image of a Japanese character.[1]