Key points are not available for this paper at this time.
The previous work of Gerchberg Opt. Acta 21, 709 (1974), Papoulis IEEE Trans. Circuits Syst. CAS-22, 735 (1975), Youla IEEE Trans. Circuits Syst. CAS-25, 694 (1978), and Stark et al. J. Opt. Soc. Am. 71, 735 (1981) on image restoration is presented in a generalized setting. New examples using three projections are given. The method is used to solve the general problem of diffraction by a perfectly conducting plane screen of arbitrary configuration.
W. Duane Montgomery (Fri,) studied this question.