Investigating photomultiplier tube nonlinearities in high-speed phosphor thermometry using light emitting diode simulated decay curves

• DOI: 10.1063/5.0063230
• Publication Date: 2021-12-02T13:49:59Z
• Authors: Henrik Feuk; Sebastian Nilsson; Marcus Aldén; Mattias Richter
• Keywords: Photocathode; Radiant flux; Rise time

Photomultiplier tube (PMT) nonlinearities relevant for single shot high-speed lifetime phosphor thermometry were investigated by simulating decay curves with a light emitting diode (LED) at repetition rates between 1 Hz and 10 kHz. The PMT gain, LED time, background radiant flux also varied to investigate their impact on the measured time error. Errors in due nonlinear performance lead temperature measurement errors; therefore, having sensitive only is highly valuable more reliable measurements. Photocathode bleaching had significant signal level linearity PMTs excitation frequency kHz regime but smaller Space charge effects most noticeable high levels rates. Strong may errors, gateable photocathode could be an effective method reduce errors. best configuration maximize precision without sacrificing accuracy use gain recommended range highest where response still linear. degree of nonlinearity partly detector dependent; results this work differ among detectors; however, analysis presented provides guidelines improving