Interference between stretched and original pulses.

ABSTRACT

An off-axis holographic recording method for fast-moving objects that has a time resolution of several picoseconds and a large depth of field is suggested. Two different but mutually coherent laser pulses, the original pulse (20 ps) and a stretched pulse (60 ps), are interfered. The short pulse determines the resolution, and the stretched pulse increases the field depth. Interference patterns between the short and the expanded pulses, for lambda = 1.064 microm and lambda = 0.532 microm, are demonstrated.