Abstract

The superresolution technique,¹ described before, is extended to the case of polychromatic illumination, using either a point or an extended source. The procedure requires an interferometer that produces white light fringes. A spatial filtering and imaging system is then incorporated into one branch of the interferometer without destroying the white light fringe capability. The grating interferometer has the required capability. The other branch is left empty, that is, contains no signal or spatial filter, used only for path matching. The interference pattern is recorded as an image plane hologram. For an imaging system with a pinhole aperture stop, resolution of the image formed in the first diffracted order of the hologram is found to be proportional to the combination of source size and spectrum bandwidth, be largely free from the resolution-limiting effect of the finite aperture.

© 1989 Optical Society of America