MTF Simulation Including Transmittance Effects and Experimental Results of Charge-Coupled Imagers

A modulation transfer function (MTF) model for front-illuminated charge-coupled imagers (CCI´s) which takes into account the periodically varying light transmittance of the photoelement array surface is derived. An inexpensive direct MTF measurement technique for CCI´s was developed and is described. Experimental MTF measurements confirm the complete MTF model. Spatial resolution measurements and MTF simulation results of practical CCI photoelement array structures show that the periodically varying surface-light transmittance of the photoelement array contributes significantly to the behavior of the overall MTF and aliasing of the imager.