J. van der Gracht

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An important approach for extending depth-of-focus is to insert a phase mask directly into the imaging system to increase the focus invariance of the point spread function (PSF). The process results in an intermediate image that us blurred in a spatially invariant way. In this paper we consider some linear and nonlinear iterative techniques for restoring(More)
An integrated array imaging system, dubbed PERIODIC, is presented which is capable of exploiting diversities including sub-pixel displacement, phase, polarization, neutral density, and wavelength, to produce high definition images. The optical hardware system and software interface are described, and sample results are shown. ©2007 Optical Society of(More)
Iris recognition imaging is attracting considerable interest as a viable alternative for personal identification and verification in many defense and security applications. However current iris recognition systems suffer from limited depth of field, which makes usage of these systems more difficult by an untrained user. Traditionally, the depth of field is(More)
The insertion of a suitably designed phase plate in the pupil of an imaging system makes it possible to encode the depth dimension of an extended three-dimensional scene by means of an approximately shift-invariant PSF. The so-encoded image can then be deblurred digitally by standard image recovery algorithms to recoup the depth dependent detail of the(More)
An integrated array computational imaging system, dubbed PERIODIC, is presented which is capable of exploiting a diverse variety of optical information including sub-pixel displacements, phase, polarization, intensity, and wavelength. Several applications of this technology will be presented including digital superresolution, enhanced dynamic range and(More)
Array imaging is an emerging paradigm where a specially designed array of lenslets is employed to capture an ensemble of images of a subject, enabling the collection of significantly more information than with conventional single-lens imaging systems. Thin form-factor and wide angle of view are important additional characteristics of an array imaging(More)
We investigate the use of a novel multi-lens imaging system in the context of biometric identification, and more specifically, for iris recognition. Multi-lenslet cameras offer a number of significant advantages over standard single-lens camera systems, including thin form-factor and wide angle of view. By using appropriate lenslet spacing relative to the(More)
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