A combination MODIS optics characteristics, short back focal length, and relatively distorting optics, has required major revisions in techniques used earlier to characterize effective focal length (EFL) and modulation transfer function (MTF) in the thematic mapper (TM) project. This paper compares measurement approaches used to characterize TM optics and revised methodology intended to characterize MODIS optics at an integration and assembly level.
Computer simulation has become a useful tool in the design, testing, and evaluation of
Michelson-type interferometric spectrometers. Although the general characteristics of these
instruments can be evaluated using standard textbook algorithms1 ,2 it is difficult to estimate
spectral accuracy for non-ideal instruments experiencing one or multiple operational
perturbations. Relatively simple computer simulation techniques enable display of
recovered spectra for both ideal and multiply-perturbed instruments, thereby affording the
evaluator a preview of spectral accuracy as a function of the instrument's design and