A novel method of measuring the delay between pre-ionizing and main discharges in TE gas lasers

A simple and reliable method of measurement of the very short delay (tens o f nanoseconds) between the pre-ionizing and main discharge currents in a TE A CO2 laser operated in the spiker sustainer configuration has been demonst rated. In this method light emitted from the pre-ionizing spark and the mai n discharge are first collected separately using optical fibres and then th e delay between the onsets of their emission is measured with the help of s imple opto-electronic circuits. This method is noise free, since it does no t involve measurement of large pulse currents, and can be useful for the me asurement of similar delays in the operation of other TE gas lasers.