We experimentally demonstrate a camera whose primary optic is a cannula/needle (
A lens performs an approximately onetoone mapping from the object to the image plane. This mapping in the image plane is maintained within a depth of field (or referred to as depth of focus, if the object is at infinity). This necessitates refocusing of the lens when the images are separated by distances larger than the depth of field. Such refocusing mechanisms can increase the cost, complexity, and weight of imaging systems. Here we show that by judicious design of a multilevel diffractive lens (MDL) it is possible to drastically enhance the depth of focus by over 4 orders of magnitude. Using such a lens, we are able to maintain focus for objects that are separated by as large a distance as
 NSFPAR ID:
 10139300
 Publisher / Repository:
 Optical Society of America
 Date Published:
 Journal Name:
 Optica
 Volume:
 7
 Issue:
 3
 ISSN:
 23342536
 Page Range / eLocation ID:
 Article No. 214
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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