Ron Harris (footballer) Ron Harris (footballer) Ronald Edward Harris (born 13 November 1944 in Hackney, London, England), known by the nickname "Chopper", is a former English footballer who played for Chelsea in the 1960s and 1970s. Harris is widely regarded as one of the toughest defenders of his era – along with players such as Tommy Smith and Norman Hunter – hence the nickname. His brother Allan Harris was also a professional footballer and they were teammates at Chelsea in the mid-1960s. Harris was a member of the Chelsea side which won the FA Youth Cup in 1961 and made his senior club
Optical chopper Optical chopper An optical chopper is a device which periodically interrupts a light beam. Three types are available: variable frequency rotating disc choppers, fixed frequency tuning fork choppers, and optical shutters. A rotating disc chopper was famously used in 1849 by Hippolyte Fizeau in the first non-astronomical measurement of the speed of light. Optical choppers, usually rotating disc mechanical shutters, are widely used in science labs in combination with lock-in amplifiers. The chopper is used to modulate the intensity of a light beam, and a lock-in amplifier is used to improve the signal-to-noise ratio. To be effective, an optical chopper