Abstract

Although a laser is capable of delivering orders of magnitude more photons in a smaller volume to a sample than a typical arc lamp, there has not been a concomitant decrease in the fluorescence detection limit due to the increased photon density. The reason for this phenomenon is that fluorescence is a blank limited technique. Thus, any increase in excitation power will increase the emission from both the sample and the blank. Therefore, other properties of the laser, such as production of picosecond pulses combined with time-resolved detection techniques, have been utilized to decrease the detection limit.

© 1987 Optical Society of America