Vision ray techniques are known in the optical community to provide low-uncertainty image formation models. In this work, we extend this approach and propose a vision ray metrology system that estimates the geometric wavefront of a measurement sample using the sample-induced deflection in the vision rays. We show the feasibility of this approach using simulations and measurements of spherical and freeform optics. In contrast to the competitive technique deflectometry, this approach relies on differential measurements and, hence, requires no elaborated calibration procedure that uses sophisticated optimization algorithms to estimate geometric constraints. Applications of this work are the metrology and alignment of freeform optics.
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Vision ray metrology: a new versatile tool for the metrology and alignment of optics
A novel Vision ray metrology technique is reported that estimates the geometric wavefront of a measurement sample using the sample-induced deflection in the vision rays. Vision ray techniques are known in the vision community to provide image formation models even when conventional camera calibration techniques fail. This work extends the use of vision rays to the area of optical metrology. In contrast to phase measuring deflectometry, this work relies on differential measurements, and hence, the absolute position and orientation between target and camera do not need to be known. This optical configuration significantly reduces the complexity of the reconstruction algorithms. The proposed vision ray metrology system does not require mathematical optimization algorithms for calibration and reconstruction – the vision rays are obtained using a simple 3D fitting of a line.
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- PAR ID:
- 10429453
- Date Published:
- Journal Name:
- Proceedings Volume 12223, Interferometry XXI; 1222304 (2022) https://doi.org/10.1117/12.2634327 Event: SPIE Optical Engineering + Applications, 2022, San Diego, California, United States
- Volume:
- 29
- Issue:
- 26
- Page Range / eLocation ID:
- 22
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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