PSF Characterisation and Optimisation of a CCD for the ESA Euclid Mission

As part of qualifying the Teledyne-e2v CCD273 for the visible imager (VIS) on the ESA Euclid mision, a front-illuminated CCD273 is tested in order to observe the Point Spread Function (PSF) response with respect to signal and voltage parameters. In order to achieve this an optical characterisation system with the ability to project flat-fields and precisely positioned and focused spot images is constructed and characterised. The Single-Pixel Photon Transfer Curve (SP-PTC) is devised in order to provide an analytical method for characterising the system PSF and the Brigher-Fatter Effect (BFE), a systematic spot-widening with signal, is observed. A technique for confirming the mechanism of the BFE via use of separate spot and flat-field illuminations in a single frame is devised in addition to parallel image clock electrode parametrisation. Device-specific optimisations are also presented regarding bright spot response and elimination of persistence following bright illuminations or charge occupation of the dielectric interface surface states