Ronald Driggers, Editor-in-Chief
Kaiqin Chu, Nicholas George, and Wanli Chi
Kaiqin Chu,1,* Nicholas George,1 and Wanli Chi1
1Institute of Optics, University of Rochester, Rochester, New York 14627, USA
*Corresponding author: firstname.lastname@example.org
We describe a simple method to extend the depth of field of a conventional camera by inserting a transparent annular ring in front of the pupil of the lens. The insertion of the ring creates an unbalanced optical path difference across the lens aperture, which partitions the pupil and leads to an extended depth of field. This system is analyzed by diffraction and random process theory. Experiments are reported that are in good agreement with the theory.
© 2008 Optical Society of America
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Proposed imaging system to extend depth of field: (a) the inserted plate; (b) the modified imaging system.
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Conventional imaging system.
Phase plate model for derivation of the transmission function of the glass plate.
PSF examples of a perfect lens for three object distances: (a) unpartitioned pupil, (b) partitioned pupil with unbalanced OPD, Eq. (23).
(a) Peak and (b) FWHM of the central lobe of PSF of a lens before the partition (dashed curve) and after the partition (solid curve).
PSF examples of an aberrated lens (a) without or (b) with partition,
Blurred images when the object shown in Fig. 7 is moved along the optical axis and the lens is focused at the “0” position. A segment of the image is digitally magnified and placed next to the image.
Recovery from images shown in Fig. 8.
PSF measured over different object positions.
Blurry images before digital processing.
Recovery from images shown in Fig. 11.
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