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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 21, Iss. 15 — Jul. 29, 2013
  • pp: 18079–18088

An endoscopic system adopting a liquid crystal lens with an electrically tunable depth-of-field

Hung-Shan Chen and Yi-Hsin Lin  »View Author Affiliations

Optics Express, Vol. 21, Issue 15, pp. 18079-18088 (2013)

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Conventional endoscopic systems consisting of several solid lenses suffer from a fixed and limited depth-of-field (DOF). For practical applications, conventional endoscopes mechanically change the distance between the solid lenses of a lens module in order to change the focusing plane and DOF to see clearly in a scene. In this paper, we demonstrate an electrically tunable endoscopic system adopting a liquid crystal lens. By means of tunable focusing properties of the LC lens as a positive lens and a negative lens, the object at different objective distances can be imaged to the image sensor clearly and the corresponding depth-of-field can also help to enlarge the total spatial depth perception in a scene. The optical mechanism is discussed. In the experiments, under adjustment of three discrete lens powers of the LC lens, the viewing range or total spatial depth perception of the endoscopic system is from 76.4 mm to 12.4 mm which is 2x improved compared to the conventional one without LC lens. We believe this study can be extended to the applications of industrial and medical endoscopes.

© 2013 OSA

OCIS Codes
(230.2090) Optical devices : Electro-optical devices
(230.3720) Optical devices : Liquid-crystal devices

ToC Category:
Medical Optics and Biotechnology

Original Manuscript: May 31, 2013
Revised Manuscript: July 11, 2013
Manuscript Accepted: July 13, 2013
Published: July 19, 2013

Virtual Issues
Vol. 8, Iss. 8 Virtual Journal for Biomedical Optics

Hung-Shan Chen and Yi-Hsin Lin, "An endoscopic system adopting a liquid crystal lens with an electrically tunable depth-of-field," Opt. Express 21, 18079-18088 (2013)

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