In 1932, he demonstrated ultra-short wave television.
Baird's mechanical system reached a peak of 240 lines of resolution on BBC television broadcasts in 1936, though the mechanical system did not scan the televised scene directly.
This is widely regarded as the first television demonstration in history.
The subject was Baird's business partner Oliver Hutchinson.
A selenium photoelectric tube detected the light reflected from the subject and converted it into a proportional electrical signal.
This was transmitted by AM radio waves to a receiver unit, where the video signal was applied to a neon light behind a second Nipkow disk rotating synchronized with the first.In the receiver, a type of Kerr cell modulated the light and a series of variously angled mirrors attached to the edge of a rotating disc scanned the modulated beam onto the display screen. The 8x8 pixel resolution in this proof-of-concept demonstration was just sufficient to clearly transmit individual letters of the alphabet.An updated image was transmitted "several times" each second.The Scottish inventor Alexander Bain introduced the facsimile machine between 18.The English physicist Frederick Bakewell demonstrated a working laboratory version in 1851.Instead, a 17.5mm film was shot, rapidly developed and then scanned while the film was still wet.An American inventor, Charles Francis Jenkins, also pioneered the television.Baird's system used the Nipkow disk for both scanning the image and displaying it.A bright light shining through a spinning Nipkow disk set with lenses projected a bright spot of light that swept across the subject.Baird's disk had 30 holes, producing an image with only 30 scan lines, just enough to recognize a human face.In 1927, Baird transmitted a signal over 438 miles (705 km) of telephone line between London and Glasgow.