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Title: Monolithic all-silicon flat lens for broadband LWIR imaging

We designed, fabricated, and characterized a flat multi-level diffractive lens comprised of only silicon withdiameter=15.2mm, focallength=19mm, numerical aperture of 0.371, and operating over the long-wave infrared (LWIR)spectrum=8µ<#comment/>mto 14 µm. We experimentally demonstrated a field of view of 46°, depth of focus><#comment/>5mm, and wavelength-averaged Strehl ratio of 0.46. All of these metrics were comparable to those of a conventional refractive lens. The active device thickness is only 8 µm, and its weight (including the silicon substrate) is less than 0.2 g.

 
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Award ID(s):
1936729
NSF-PAR ID:
10287082
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Letters
Volume:
46
Issue:
16
ISSN:
0146-9592; OPLEDP
Page Range / eLocation ID:
Article No. 4069
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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