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Spectrophotometer 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. Use in science laboratoriesOptical choppers, usually rotating disc mechanical shutters, are widely used in science labs in combination with. The chopper is used to modulate the intensity of a light beam, and a lock-in amplifier is. Choppers were widely used in early systems, and in this role are sometimes known as "reticle seekers". The earliest uses were on. A photocell sensitive to is positioned.
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