AN INTENSE, HIGH-REPETITION NANOSECOND LIGHT-SOURCE USING A COMMERCIALLY AVAILABLE XE-ARC LAMP

We describe the construction and emission characteristics of a Xe light source that produces broadband emission spectrum (250-650 nm) and high-repetition pulsed light of nanosecond duration. The standard dc-operated Xe-arc lamp, which is commercially available, is employed as the primary light source, with modified circuitry to realize pulsed operation. A dc voltage higher than 5 kV is applied to the electrode gap through a high-value resistor in order to generate a periodical discharge of current between the electrode pp. In order to further increase the intensity of the light pulses, the electrical polarity of the electrode must be in inverse connection relative to the normal connection under the dc operation. Intense light pulses as large as 20 W (peak value) of 3 ns width were generated repetitively from the Xe lamp. Fluorescence lifetimes of a quinine-sulfate solution and a fluorescent cell nucleus were measured to demonstrate the usefulness of the light source.