Beam overlap for long delay lines using active feedback.
A major technical difficulty in comparing picosecond experiments with nanosecond experiments is to maintain beam overlap for long optical delay lines. We describe an active feedback system for an optical delay line that maintains the beam position to within 25 mum before the focusing lens and to within less than ~2 mum in the focal region within the sample.
Doland
C
C
Jackson
W B
WB
Andersson
A
A