Experimental methods for measurement of the modulation transfer function (MTF) for time-delay-and-integrate (TDI) charge coupled device (CCD) image sensors

Abstract

In this paper we report experimental measurements of the wavelength-dependent Modulation Transfer Function (MTF) for a commercial Time-Delay-and-Integrate Charge Coupled Device (TDI-CCD) image sensor. The modulation transfer function provides a measure of the maximum spatial resolution achievable by an electro-optic (EO) image sensor. Charge diffusion and electronic crosstalk mechanisms inherent to all EO sensors will degrade the image quality and deleteriously affect the MTF; therefore measurement of the MTF for an EO image sensor provides a powerful tool for probing these mechanisms. The focus of this work will be toward describing, in detail, the unique experimental apparatus and techniques, developed at The Aerospace Corporation, that enable these measurements. Furthermore, the experimentally measured MTF will be compared to the analytical Blouke-Robinson diffusion MTF model for CCD image sensors.