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Applied Optics

Applied Optics


  • Editor: James C. Wyant
  • Vol. 47, Iss. 36 — Dec. 20, 2008
  • pp: 6895–6903

Extending the depth of field through unbalanced optical path difference

Kaiqin Chu, Nicholas George, and Wanli Chi  »View Author Affiliations

Applied Optics, Vol. 47, Issue 36, pp. 6895-6903 (2008)

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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

OCIS Codes
(030.0030) Coherence and statistical optics : Coherence and statistical optics
(100.0100) Image processing : Image processing
(110.0110) Imaging systems : Imaging systems
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(130.0130) Integrated optics : Integrated optics
(220.0220) Optical design and fabrication : Optical design and fabrication

ToC Category:
Coherence and Statistical Optics

Original Manuscript: September 3, 2008
Manuscript Accepted: October 28, 2008
Published: December 19, 2008

Kaiqin Chu, Nicholas George, and Wanli Chi, "Extending the depth of field through unbalanced optical path difference," Appl. Opt. 47, 6895-6903 (2008)

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