Simulation of the modulation transfer function of a projecting optical system

Effects of MTF limitations of projecting lenses are investigated. A theory of optical imaging is summed up for adjusted calculations. Imaging by the lens system in a special schlieren-optical arrangement of a color TV projector is simulated by spatial frequency filtering. A sinus modulation of carrier gratings is written into the control layer of a single light valve. The dark field image of this phase object is considered as an example of signals to be transmitted. A modification of the power spectrum of the object intensity is proposed to estimate the influence of an optical arrangement to be designed for a high-definition TV projector. Test functions in the spatial frequency plane shaped to an experimental MTF curve are used for calculations. The demands on the projection lenses are found to be independent of the chosen carrier gratings. The effect of wave aberration on signal transmittance is outlined.