Optical limiter using a lead phthalocyanine

The performance of an optical limiter based on Pb-tetrakis(cumylphenoxy)phthalocyanine, a robust organic material with a large χ(3) and figure of merit, χ(3)/α0, is described. In an f/5 limiter with a sample transmission of 0.68, the threshold for limiting was 8±2 nJ and the dynamic range was greater than a factor of 103. The threshold for the PbPc(CP)4 limiter was ∼15 times smaller and the high intensity transmission ∼4–5 times lower than an equivalent limiter based on a thermal nonlinearity.