A single-mode star network, made from polarization-preserving components, can perform the spatial discrete Fourier transform of coherent light patterns presented at the inputs. This can be accomplished with passive components, such as 2 × 2 couplers, and propagation delays. The Hadamard transform can be performed similarly.
© 1987 Optical Society of America
Original Manuscript: August 4, 1986
Manuscript Accepted: October 15, 1986
Published: January 1, 1987
M. E. Marhic, "Discrete Fourier transforms by single-mode star networks," Opt. Lett. 12, 63-65 (1987)