Towards Improved Optical Limiters
Abstract
Optical limiters are materials that are transparent to low-intensity, ambient light but become opaque to high-intensity light. Such materials are of particular interest to the Navy for protecting optical sensors and human eyes from battlefield lasers. The most successful optical limiters known are soluble phthalocyanines, in particular those metallated with lead and indium. Yet further improvements are needed. This research project used a two-pronged approach to create improved optical limiters. The first approach was to synthesize and study soluble thallium phthalocyanines. Thallium, due to its proximity to lead and indium on the periodic table, should exhibit favorable optical limiting properties. Yet soluble thallium phthalocyanines had never been synthesized. A substituted thallium(III) phthalocyanine complex which is readily soluble in organic solvents has been prepared. The second approach to improved optical limiters was to prepare covalently-linked phthalocyanine complexes which allow control of aggregation, an important parameter affecting optical limiting properties. Towards this end, a clamshell' phthalocyanine dimer has been prepared and metallated with lead. Both of these new materials, the soluble thallium phthalocyanine and the lead phthalocyanine dimer, have been characterized using UV-vis and NMR spectroscopy and mass spectrometry. Their optical properties have been examined using Z-scan and Degenerate Four Wave Mixing (DFWM) techniques.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 03, 2002
- Accession Number
- ADA403458
Entities
People
- Peter D. Huffman
Organizations
- United States Naval Academy