Optical Sine transformation and image transmission by using square opticalwaveguide

In this paper a system able to perform all optically the discrete-Sine tran sformation is discussed, Similar to that proposed previously [C.Y. Wu, A.R. D. Somervell, T.H. Barnes, Opt. Commun. 157 (1998) 17-22], the new system i s also composed of a piece of perfectly reflecting square-optical fiber (wa veguide) and lens systems but with the input image being directly projected on to the front face of the fiber. At the other end of the fiber the field is transformed by a Fourier lens and projected on to a screen. Theoretical analysis shows that the electric field on the output screen represents exa ctly the discrete-Sine transform of the input image when a spherically symm etrical phase term is compensated and the original image can be restored by sending the Sine transformed field back through the same system. Phase com pensation methods are discussed. The analysis is confirmed by a numerical s imulation. (C) 2000 Published by Elsevier Science B.V. All rights reserved.