In the late 1940s at Bell Labs a raft of teams were looking at different areas of semiconductor technology. Spurred on by the invention of the point contact transistor a number of other developments were announced and although they are not as widely publicised, they also had a major impact on the advancement of the electronics industry. One early but very significant development that occurred early on in the history of the transistor was that of the phototransistor. Nowadays, phototransistor technology is taken for granted, and the devices are widely used, but nevertheless this was an important semiconductor technology development.