Apparatus and methods for measuring cathode fall in fluorescent lamps are disclosed. Together with measurements of cathode temperature, such measurements of cathode fall may inform a determination of cathode heater voltage as a function of discharge current (i.e., a cathode-heating-profile) that avoids...http://www.google.de/patents/US7196476?utm_source=gb-gplus-sharePatent US7196476 - Apparatus and methods for making capacitive measurements of cathode fall in fluorescent lamps
