Paper
23 September 2015 Overview on surface representations for freeform surfaces
H. Gross, A. Brömel, M. Beier, R. Steinkopf, J. Hartung, Y. Zhong, M. Oleszko, D. Ochse
Author Affiliations +
Abstract
Freeform surfaces are a new and exciting opportunity in lens design. The technological boundary conditions for manufacturing surfaces with reduced symmetry are complicated. Recently the progress in understanding and controlling this kind of components is ready for use in commercial products. Nearly all procedures of classical design development are changing, if freeform surfaces are used. The mathematical description of the surfaces, the optimization algorithms in lens design and their convergence, the initial design approaches, the evaluation of performance over the field of view, the data transfer in the mechanical design software and in the manufacturing machines, the metrology for characterization of real surfaces and the return of the real surfaces into the simulation are affected. In this contribution, in particular an overview on possible mathematical formulations of the surfaces is given. One of the requirements on the descriptions is a good performance to correct optical aberrations. After fabrication of real surfaces, there are typical deviations seen in the shape. First more localized deformations are observed, which are only poorly described by mode expansions. Therefore a need in describing the surface with localized finite support exists. Secondly the classical diamond turning grinding process typically shows a regular ripple structure. These midfrequency errors are best described by special approaches. For all these cases it would be the best to have simple, robust solutions, that allow for fast calculation in fitting measured surfaces and in raytrace.
© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
H. Gross, A. Brömel, M. Beier, R. Steinkopf, J. Hartung, Y. Zhong, M. Oleszko, and D. Ochse "Overview on surface representations for freeform surfaces", Proc. SPIE 9626, Optical Systems Design 2015: Optical Design and Engineering VI, 96260U (23 September 2015); https://doi.org/10.1117/12.2191255
Lens.org Logo
CITATIONS
Cited by 13 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Spatial frequencies

Manufacturing

Optical design

Tolerancing

Metrology

Error analysis

Optical spheres

RELATED CONTENT

Description and tolerancing of freeform surfaces in standards
Proceedings of SPIE (December 17 2014)
A Statistical Approach To Lens Tolerancing
Proceedings of SPIE (December 01 1978)
The cost of tolerancing
Proceedings of SPIE (August 28 2009)

Back to Top