PICOSECOND LIGHT PULSE DISPLAY USING TWO DIFFERENT OPTICAL FREQUENCIES

Abstract

A new technique for the display and measurement of picosecond light pulses is demonstrated. Two picosecond pulses, of different optical frequencies, are sent on a collision course in a liquid. They produce strong two‐photon fluorescence only in the region where they overlap. This results in the direct display of the pulse shapes over a very weak background. In a different arrangement, the two pulses enter the liquid collinearly and simultaneously, and initially generate strong two‐photon fluorescence. Subsequently, as the pulses propagate through the liquid, dispersion causes one pulse to overtake the other and the two‐photon fluorescence diminishes. This results in a magnified display of the pulses.