[50] Picosecond spectroscopy of visual pigments

Publisher Summary This chapter discusses the picosecond spectroscopy of visual pigments. Technological developments in picosecond spectroscopic instrumentation have made it possible to investigate early dynamic events in photobiological systems. Picosecond kinetics and spectroscopy are practiced by a large number of investigators emphasizing either absorption, emission, or, lately, resonance Raman spectroscopy. The experimental systems employed are quite similar and with a reasonable effort can be converted from one task to another. Three considerations of visual pigment preparations are of particular concern for picosecond spectroscopy. The concentrations should be relatively high for a biological sample, so that short sample pathlengths may be used for coinciding excitation and monitoring pulses, yet avoid self-absorption and nonlinear effects.