Photon Counting with Intensified Solid State Arrays

Abstract

Publisher Summary This chapter discusses the photon counting with intensified solid state arrays. The photon counting array (PCA) system has certain objectives: count every photoelectron; count these only once; centre the photon event pulse to obtain maximum resolution; and eliminate all non-photon noise. The spectrum is imaged onto a tandem stack of six electrostatically focused, fiber optically coupled 40 mm diameter image tubes. The image tubes provide sufficient gain so that the video pulses from the diode array are much larger than the preamplifier noise. A feature of the MOS arrays is that the video signal is superimposed on a coherent clock noise level. The experience with linear arrays encourages one to believe that a similar approach to the use of two-dimensional CCD arrays will prove fruitful. For spectroscopic use, it is believed that a system such as the PCA where detective quantum efficiency is nearly equal to the theoretical quantum efficiency has advantages over the use of the unintensified CCD with its high theoretical QE and attendant problems of charge leakage, diode non-uniformity, high dark current, and low noise preamplifier requirements.