This paper presents recent experimental and theoretical results regarding the dynamic range and noise performance of ICCD cameras which use micro-channel plate (MCP) image intensifiers. Vendor specifications for image intensifiers using these devices suggest that the noise factor is in the range of 1.6 to 2.2 for Gen II intensifiers and 3.5-4.2 for Gen III intensifiers which use filmed MCPs to extend the GaAs photo cathode lifetime. Our experimental results suggest that the ICCD noise factor increases dramatically as the gain is reduced to accommodate higher background light levels. Noise factors in excess of 60 have been observed. For most applications where the MCP is operated at high gain, this behavior is never encountered. However, for applications which use the MCP as a low-gain device, such as active laser range-gated systems operated in high background reflectance conditions, the imaging performance can be severely degraded. A model for the gain dependent ICCD noise factor has been developed which will be compared with the experimentally observed effects. Keywords: Micro-channel Plate, MCP, Noise Factor, Intensified CCD, ICCD, Dynamic Range, Range-Gating, Laser LineScan.
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