A DIFFERENTIAL METHOD FOR THE MEASUREMENT OF ATTENUATION OF PULSED LASER BEAMS.
BALLISTIC RESEARCH LABS ABERDEEN PROVING GROUND MD
Pagination or Media Count:
A differential transformer system has been developed to measure the attenuation of short-duration, high-energy laser pulses in a contaminated atmosphere. Photodiodes at each terminus of the laser path produce electrical pulses which are proportional to the laser beam energy. These pulses are applied to opposite sides of the transformer primary and cause a difference signal to appear across the secondary winding. The difference signals can be resolved for input signals of magnitudes as high as several hundred volts and of durations as short as twenty nanoseconds. With an input reference signal of fifty volts, the measurement of the difference signal is accurate to within 0.3 db in attenuation. Precision is limited by oscilloscope resolution. Author
- Lasers and Masers