In this study, a novel fabrication process, to the best of our knowledge, was developed to fabricate a glass harmonic diffractive lens. In this process, a polymethylmethacrylate master of the diffractive lens was machined using single-point diamond turning. Then an electrolytic plating process was conducted to grow a reverse nickel (Ni) mold. Precision compression molding was performed using the Ni mold to replicate the diffractive lens structures onto a glass surface. Surface measurements and optical testing show that the replicated diffractive lenses by the proposed method have high tolerances and require optical performance, demonstrating a high-volume, high-precision, and cost-effective process. The proposed method will be critical for consumer products where glass optics are increasingly used in lens assemblies.
Predictive models for the Strehl ratio of diamond-machined optics
This paper provides a practical connection between the Strehl ratio as an optical performance metric and manufacturing
parameters for diamond-machined optics. The choice of fabrication parameters impacts residual midspatial
frequency groove structures over the part’s surface, which reduce optical performance. Connections between
the Strehl ratio and the fabrication parameters are studied using rigorous Rayleigh–Sommerfeld simulations for
a sample optical system. The connections are generalized by incorporating the shape of diamond-machined groove
structures and the effects of optical path differences for both transmissive and reflective optics. This work validates
the analytical representation of the Strehl ratio as a Fourier transform of a probability density that relates to surface
errors. The result is a practical tool that can be used to guide the choice of machining parameters to achieve
a targeted optical performance. © 2019 Optical Society of America
https://doi.org/10.1364/AO.58.003272
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- NSF-PAR ID:
- 10161238
- Date Published:
- Journal Name:
- Applied optics
- Volume:
- 58
- Issue:
- 12
- ISSN:
- 1559-128X
- Page Range / eLocation ID:
- 3272-3276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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