Method of Calculating the Effective Intensity of Multiple-Flick Flashtube Signals

摘要

The purpose of this work was to devise a method of determining the effective intensity of light flashes composed of multiple pulses (flicks) of light. Detection thresholds were measured for such flashes when the flick frequency and flash duration were varied. Thresholds decreased with increasing flick frequency and flash duration. At each flick frequency the relationship between threshold and flash duration was well-characterized by the Blondel-Rey relation (a=0.2) provided a multiplicative frequency-dependent fitting parameter was chosen. The fitting parameter, beta, increases linearly with frequency between 5 and 20 Hz. A method of determining effective intensity was described which uses the flick frequency, number of flicks and the calculated effective intensity of a single flick to arrive at the solution. It was concluded that this method should be used for all multiple flick signals provided the single-flick duration is less than 0.01 sec and the frequency is between 5 and 20 Hz. The method of Allard should not be used, as it consistently overestimates effective intensity. Keywords include: Effective intensity, Method of Allard, Allard's law, Multiple-flick flash, Flick frequency, Flash length, and Flashtube.