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Specification and tolerancing of surfaces with mid-spatial frequency (MSF) errors are challenging and require new tools to augment simple surface statistics to better represent the structured characteristics of these errors. A novel surface specification method is developed by considering the structured and anisotropic nature of MSF errors and their impact on the modulation transfer function (MTF). The result is an intuitive plot of bandlimited RMS error values in polar coordinates which contains the surface error anisotropy information and enables an easy to understand acceptance criterion. Methods, application examples, and the connection of this surface specification approach to the MTF are discussed. © 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
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Non-Directional Modulation Transfer Function for Optical Surfaces with Anisotropic Mid-Spatial Frequency Errors
Sub-aperture manufacturing creates anisotropic surface errors, and modulation transfer functions (MTF) not well represented by 1D cross-sections. We present a 1D ‘non-directional’ MTF for specification and characterization of optical surface errors. © 2019 The Author(s) OCIS codes: (110.4100) Modulation transfer function; (220.0220) Optical design and fabrication.
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- PAR ID:
- 10161186
- Date Published:
- Journal Name:
- Design and Fabrication Congress 2019 (Freeform, OFT)
- Volume:
- OT1A.2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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