*** ABSTRACT 96-61596 Kane This Small Business Innovation Research Phase I project will develop an algorithm for the real-time inversion of spectrograms for ultrashort laser pulse measurement. Ultrafast laser systems have a large number of applications in biochemistry, chemistry, physics, and electrical engineering. These systems generate laser pulses with durations of 10 picoseconds or less and such systems are used to explore kinetics in proteins, examine carrier relaxation in semiconductors, or image through turbid media. By using ultrafast diagnostic systems, highly advanced semiconductors, electronic circuitry, and even biomedical products can be developed and tested for commercial applications. Furthermore, new applications requiring shaped ultrashort pulses in both intensity and phase-such as coherent control of chemical reactions are beginning to be developed. The continued development of these applications will require, fast, high quality, and easy-to-use ultrafast laser pulse diagnostics. Frequency-resolved optical gating (FROG) has been proven to be a reliable and effective ultrashort laser pulse diagnostic, but requires an iterative algorithm to obtain the ultrashort pulse's characteristics (intensity and phase). Current inversion algorithms are slow. During the Phase I research effort, a new inversion algorithm will be developed that will obtain the intensity and phase of an ultrashort pulse from the FROG device's output in real time facilitating the development of a real-time oscilloscope for ultrashort laser pulses. Immediate commercial applications are directed toward use as a diagnostic for existing ultrafast laser systems for which few are currently available. Other commercial applications for the algorithm include scanning transmission electron microscopy. ***
