General optical setups that implement the fractional Fourier transforms are proposed by use of the impulse response theory. These architectures are demonstrated to be flexible in practical spatially variant filtering systems that employ cascaded multiple stages of fractional Fourier transforms, because of their capabilities of changing the standard focal length.
© 1995 Optical Society of America
Shutian Liu, Jiandong Xu, Yan Zhang, Lixue Chen, and Chunfei Li, "General optical implementations of fractional Fourier transforms," Opt. Lett. 20, 1053-1055 (1995)