Streak camera

A streak camera is an instrument for measuring the variation in a pulse of light's intensity with time. They are used to measure the pulse duration of some ultrafast laser systems and for applications such as time-resolved spectroscopy and LIDAR.

A streak camera forms a 2-D image in which one dimension is distance across its input surface and the other is time, much like a line-scan camera, strip photography, photo finish camera, and others. If the input source is the output of a prism or diffraction grating, the resulting 2-D image shows the entire spectrogram as it varied over time. (An analog oscilloscope can capture changes over continuous time, but it can only record the changes of one point (per channel), in each sweep. A streak camera tracks a continuum of points (effectively hundreds to millions), over continuous time, in each exposure.)

An optoelectronic streak camera, after it is triggered, captures the incoming line image as it changes, usually over an extremely short time. (If extreme speed is not needed, a high-speed camera could be used instead. It captures an entire 2-D scene in each frame, but any unneeded or unuseful information is easily discarded.) The formed 2-D image is then collected (usually at an ordinary speed) before the streak camera is ready to be triggered again.