Streak Camera - Optoelectronic Type

Optoelectronic Type

Optoelectronic streak cameras work by directing the light onto a photocathode, which when hit by photons produces electrons via the photoelectric effect. The electrons are accelerated in a cathode ray tube and pass through an electric field produced by a pair of plates, which deflects the electrons sideways. By modulating the electric potential between the plates, the electric field is quickly changed to give a time-varying deflection of the electrons, sweeping the electrons across a phosphor screen at the end of the tube. A linear detector, such as a charge-coupled device (CCD) array is used to measure the streak pattern on the screen, and thus the temporal profile of the light pulse.

The time-resolution of the best optoelectronic streak cameras is around 100 femtoseconds. Measurement of pulses shorter than this duration requires other techniques such as optical autocorrelation and frequency-resolved optical gating (FROG).

In December 2011, a team at MIT released images combining the use of a streak camera with repeated laser pulses to simulate a movie with a frame rate of one trillion per second.