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  • Telecentric broadband objective lenses for optical coherence tomography (OCT) in the context of low uncertainty metrology of freeform optical components: from design to testing for wavefront and telecentricity
Title: Telecentric broadband objective lenses for optical coherence tomography (OCT) in the context of low uncertainty metrology of freeform optical components: from design to testing for wavefront and telecentricity
Freeform optical components enable significant advances for optical systems. A major challenge for freeform optics is the current lack of metrology methods with measurement uncertainty on the order of tens of nanometers or less. Towards addressing this challenge, optical coherence tomography (OCT) is a viable technique. In the context of low uncertainty metrology, the design requirements pertaining to the sample arm of an OCT metrology system are explicitly addressed in this paper. Two telecentric, broadband, diffraction limited, custom objective lens designs are presented with their design strategies. One objective lens was fabricated and experimentally tested for wavefront performance and telecentricity. This lens demonstrates near diffraction limited performance and a maximum deviation from telecentricity of 8.7 arcseconds across the full field of view, correlating to measurement uncertainty of less than 12 nm in simulation. The telecentricity test method developed completes the loop with respect to the design requirements and strategies presented and provides further intuition for telecentric lens designs in general. © 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement  more » « less
Award ID(s):
1822049 1338877
PAR ID:
10161247
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Optics express
Volume:
27
Issue:
5
ISSN:
1094-4087
Page Range / eLocation ID:
6184-6200
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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