A fundamental study on imaging with an off-axis Fresnel zone plate

An off-axis Fresnel zone plate, through use of a halftone screen to introduce a spatial carrier frequency, can be used as a large-area, coded aperture for imaging incoherent radiation sources. This paper discusses the structure of off-axis Fresnel zone plate as an aperture and the mentods of imaging from the viewpoint of the spatial resolution by optical simulation, appending some examples of objects, holograms and reconstructed images. It is then concluded that the off-axis Fresnel zone plate having D (diameter) = 5.8 cm and nuc (spatial center frequency) = 23 l/cm is sufficient for the reconstructed images.