title: Broadband behavior of an optical-digital focus-invariant system.
abstract: We present experimental evidence that demonstrates a greatly increased depth of field in a broadbandilluminated imaging system through the use of a special-purpose phase mask and digital filtering. The phase mask is of a simple rectangularly separable cubic-phase design, whereas the digital filtering used was a simple object-independent least-squares inverse filter. We demonstrate successful operation of the system over a range corresponding to 30 times the Hopkins criterion for allowable misfocus.
authors.forename: J
authors.initials: J
authors.lastname: van der Gracht
authors.forename: E R
authors.initials: ER
authors.lastname: Dowski
authors.forename: M G
authors.initials: MG
authors.lastname: Taylor
authors.forename: D M
authors.initials: DM
authors.lastname: Deaver