A laser beam is used to probe an integrated circuit device under test. A single laser provides a single laser pulse which is divided into two pulses, both of which are incident upon the device under test. After the two pulses interact with the device under test, the two pulses are separated and detected...http://www.google.com/patents/US6252222?utm_source=gb-gplus-sharePatent US6252222 - Differential pulsed laser beam probing of integrated circuits
