THE MEGAPIXEL EBCCD - A HIGH-RESOLUTION IMAGING TUBE SENSITIVE TO SINGLE PHOTONS

A hybrid image-intensifier tube, suitable for extremely low-light imag ing, has been tested. This device is based on an Electron-Bombarded CC D chip (EBCCD) with 1024 x 1024 sensitive pixels. The tube, which has a photocathode diameter of 40 mm, is gateable and zoomable, with an im age magnification varying from 0.62 to 1.3. The high gain labour 4000 collected electrons per photoelectron at the operational voltage of 15 kV) and the relatively low noise (180 electrons per pixel at 10 MHz p ixel-readout frequency), allows single-photoelectron signals to be sep arated from noise with a signal-to-noise ratio greater than 10. By app lying an appropriate threshold on the signal amplitude, the background can almost be eliminated, with a loss of few percent in single-photoe lectron counting. High inner gain, low-noise, single-photoelectron sen sitivity, and high spatial resolution make the EBCCD imaging tube a un ique device, attractive for many applications in high-energy physics, astrophysics and biomedical diagnostics. (C) 1998 Elsevier Science B.V . All rights reserved. (C) 1998 Elsevier Science B.V. All rights reser ved.