Subpixel sensitivity map for a charge-coupled device sensor
Abstract
The sensitivity across a solid state detector array varies as a
result of differences in transmission, diffusion and scattering properties
over the sensor. This variation will occur over a range of scale lengths
and its knowledge is of importance for improved device design and in a
variety of applications, for example, event centroiding in photon counting
systems. A measurement of the sensitivity variation on a subpixel scale
for a two-phase front-illuminated CCD is reported. The measurement is
made using a scanning reflection microscope. A variation in sensitivity
between the phases within a pixel is clearly observed, as well as variations
on a much smaller spatial scale.