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Title: Calibration method for an extended depth-of-field microscopic structured light system
This paper presents a calibration method for a microscopic structured light system with an extended depth of field (DOF). We first employed the focal sweep technique to achieve large enough depth measurement range, and then developed a computational framework to alleviate the impact of phase errors caused by the standard off-the-shelf calibration target (black circles with a white background). Specifically, we developed a polynomial interpolation algorithm to correct phase errors near the black circles to obtain more accurate phase maps for projector feature points determination. Experimental results indicate that the proposed method can achieve a measurement accuracy of approximately 1.0 μ m for a measurement volume of approximately 2,500 μ m (W) × 2,000 μ m (H) × 500 μ m (D).  more » « less
Award ID(s):
1763689
NSF-PAR ID:
10353123
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Optics Express
Volume:
30
Issue:
1
ISSN:
1094-4087
Page Range / eLocation ID:
166
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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