Detectors

In order to take full advantage of the telescope resolution, both the pair of MCPs in the detector and the resistive anode readout system are curved, like a watchglass, to match the optimum focal surface. A CsI photocathode is deposited directly onto the front face of the front MCP to enhance the EUV quantum efficiency.   The detector spatial resolution is substantially (a factor >2) better than that of the mirror nest and consequently does not contribute significantly to the net performance of the WFC. A focal plane turntable can be used to select one of two identical detector assemblies in flight. Table 6.2 gives details of the detectors.