An off-axis Fresnel zone plate may be used as a large-area "coded" aperture for imaging incoherent sources. The zone plate is sufficiently coarse that only shadow-casting, and not diffraction, is involved. It is shown here that the usefulness of this system can be greatly increased by using a half-tone screen to introduce a spatial carrier frequency and heterodyne the object spectrum into the passband of the zone plate.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering