99-28U

On the base of a method of the coordinate-phase distribution of sygnals, the optical properties of binary phase elements (BPE) are described. Expressions for the autocorrelation functions and for the Wiener spectrum of spatial frequences of a BPE are obtained. This allowed to compute a generalized optical parameter $|\varphi (k, \ l)|^2$, which is then used for quantitative estimating optical noise level. It is also shown that this parameter characterizes the average value of fluctuations of the interference intensity of Wiener spectra. A nonorthogonality parameter $d_A$ is proposed for classifying BPE, it varies from $d_A=0$, for orthogonal BPE, up to the value $d_A=N^2$, for collinear BPEs.