Oramics machine helped create electronic music
4 April 2011 Last updated at 07:56 BST
Science Museum curator Dr Tim Boon talks about the importance of Daphne Oram's Oramics Machine to electronic music.
The technique, developed in the 1950s and 1960s, created synthesized sounds by shining light through strips of 35mm film.
Painted patterns blocked parts of the beams, creating music.