Optical Ranicon detectors for photon counting imaging. I

Abstract

We discuss the design and development of Ranicon detectors for optical photon counting imaging on ground-based telescopes. The significant factors which determine the performance of these detectors are found to be the proximity focusing stage, the microchannel-plate stack (MCP), and the signal processing electronics. For applications in optical astronomy, the low photon counting efficiency typically found with optical MCP-based detectors, due to ion barrier films, presents an additional consideration. We review the performance of each stage of the Ranicon detector and the techniques for achieving optimal performance. A new approach to the signal processing electronics reduces nonlinearity, while achieving increased processing speeds and a position error corresponding to <21 μm FWHM. A significant improvement in detector performance is achieved with an advanced Ranicon incorporating a reduced proximity focusing gap and an unfilmed input plate in the MCP stack. The theoretical spatial resolution of both standard and advanced Ranicon designs is derived and compared to the experimentally determined values. For the advanced Ranicon, this spatial resolution is shown to be typically 40 μm FWHM at ∼650 nm. The point spread function of the Ranicon system is shown to be stationary over the active imaging area, principally due to the removal of nonlinearities and noise sources from the signal processing electronics.

Wide-field TCSPC: methods and applications

“…The first design suffered from many drawbacks, such as poor spatial resolution, nonlinearity across the anode, fixed pattern noise from the signal digitization, and variation in resolution due to a wide pulse height distribution. Some characteristics were improved by an optimised design of the MCP stack, the anode and the signal processing electronics and arithmetic [107]. Others, however, such as slow event processing rate (i.e.…”

Modern optical astronomy: technology and impact of interferometry

“…Several 2-d photon-counting sensors that allow recording of the position and time of arrival of each detected photons have been developed such as, (i) precision Analog Photon Address (PAPA; Papaliolios et al 1985), (ii) resistive anode position detector (Clampin et al 1988), (iii) multi anode micro-channel array (MAMA; Timothy, 1993), (iv) wedgeand-strip anodes, (v) delay-line anodes, (vi) silicon anode detector etc. Baring PAPA which is based on a high gain image intensifier and a set of photomultiplier tubes, these sensors detect the charge cloud from a high gain MCP.…”

An MCP-based detector array with integrated electronics

“…Position sensitive detectors based on charge division techniques give a continuous variation in output depending on the position of the event. Charge division detectors fall into three categories: resistive anode and capacitive charge division, [13,14,19,20,23,25,35]; delay line techniques [22,26,[36][37][38][39][40]; and shaped anodes [21,[41][42][43][44].…”

“…The methods of determining the position of ion impact fall into three basic categories: discrete anode and coincidence arrays [2][3][4][5][6][7][8][9][10][11]; charge division [12][13][14][15][16][17][18][19][20][21][22][23][24][25]; and optical imaging detectors [26][27][28][29][30][31][32][33][34]. As will be seen, E-mail: dpl@aber.ac.uk each of these detection techniques makes a different trade-off in terms of performance, component count and complexity.…”