The mechanism of the charge carrier photogeneration in Y-form titanyl phthalocyanine was investigated by means of fluorescence and photocurrent measurements. Sample excitation by two time-separated light pulses was applied to obtain information on the time course of the fluorescence and generation processes. Charge carrier precursors-charge pairs-were found to be generated only during the short time interval after the exciton was created. This interval is much shorter than the fluorescence state lifetime. (C) 1997 American Institute of Physics.