A linear self-scanning array of 512 elements was exposed to photoelectron bombardment in a Kron camera tube. This is a demountable tube in which the photocathode and the electron focal plane can be separated by means of a special coin valve. The diode array was mounted in the electron optical focal plane. The video signal amplitude distributions were analyzed when the diode array was exposed to electrons between 30 keV and 35 keV. The distribution of the signals due to single electrons could be resolved from the distribution of signals when no photoelectrons were present. The impairment of the SNR due to the lack of perfect resolution of the distributions amounts to no more than the loss of a few percent of the photoelectrons. The result of these tests encourages the immediate application of the diode array Kron tube spectrography to high resolution spectroscopy of very faint objects.
S. B. Mende and F. H. Chaffee, "Single electron counting by self-scanning diode array in a Kron camera," Appl. Opt. 16, 2698-2702 (1977)