title: Depth of field extension with spherical optics.
abstract: The introduction of spherical aberration in a lens design can be used to extend the depth of field while preserving resolution up to half the maximum diffraction-limited spatial frequency. Two low-power microscope objectives are shown that achieve an extension of +/- 0.88 lambda in terms of wavefront error, which is shown to be comparable to alternative techniques but without the use of special phase elements. The lens performance is azimuth-independent and achromatic over the visible range.
authors: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. pantazis.mouroulis@jpl.nasa.gov
authors: Pantazis
authors: P
authors: Mouroulis
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D007909:Lenses; D008853:Microscopy / Q000295:instrumentation*