We report experimental results of using an f/5 , cascaded-focus optical geometry for a high-dynamic-range optical limiter. The device consists of a 2-cm-thick CS<sub>2</sub> cell at the first focus and a reverse saturable-absorber dye in a thin cell (0.1 mm) at the second focus. The strong self-focusing in the CS<sub>2</sub> that is due to the ac Kerr effect and electrostriction keeps the energy at the second cell below its damage threshold. Using lead phthalocyanine in chloroform as the reverse saturable-absorption material, we clamped the maximum output energy below 1μJ for input energies up to 14.5 mJ without damage. We used a frequency-doubled, Q -switched 5-ns (FWHM) Nd:YAG laser operating at a 10-Hz repetition rate. The measured dynamic range of the device is at least 7500.
© 2000 Optical Society of America
F. E. HernÃÂndez, S. Yang, E. W. Van Stryland, and D. J. Hagan, "High-dynamic-range cascaded-focus optical limiter," Opt. Lett. 25, 1180-1182 (2000)