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Virtual Only

15-Tolerancing of Optical Systems for Precision Engineers

Julie Bentley, University of Rochester

Tuesday, October 11, 2022
1:30PM – 5:30PM (PDT USA)


This tutorial provides an overview of optics, optical design, and optical systems and answers questions like “why do I need a lens?” “how do I specify an optical system?” and “where do these crazy optical tolerances come from?”.  The tutorial begins with a review of geometrical optics where optical concepts such as focal length, index of refraction, dispersion, optical axis, resolution, and aberrations will be explained.  The design of common optical systems including cameras, microscopes, and telescopes will be discussed. A comparison between a simple copier lens and a complex lithography lens used to print computer circuit boards will be used to explain why some optical designs require precision mechanics and precision assembly and some do not.  A short demo of optical design software is included. No previous background in optics or optical design is required – the course is intended to provide an overview of lens design techniques at a very basic level.  The target audience for this tutorial is intended to be practicing engineers from other disciplines interested in learning about lens design.  Only knowledge of basic physics will be assumed.


Julie Bentley received her BS, MS, and PhD degree in optics from the Institute of Optics, University of Rochester. Her PhD thesis focused on the integration of the design and manufacture of gradient-index optical systems. After graduating she spent two years at Hughes Aircraft Co. in California designing optical systems for the defense industry and twelve years at Corning Tropel Corporation in Fairport, New York, designing and manufacturing precision optical assemblies such as micro lithographic inspection systems. She has been teaching optical design courses at the University of Rochester since 1998. Her main teaching interests include geometrical optics, optical design, and tolerancing. She also runs an optical design consulting company – Bentley Optical Design.

Bentley is a fellow of both SPIE and OSA and has served as the president of the local OSA chapter and a three year term on the SPIE Board of Directors. She is the co-author of the SPIE Field Guide to Lens Design (2012), a book that provides physicists, engineers, and scientists a reference for deciphering the nuances of lens design. She also recently published her second book on optical design Designing Optics with CODE V (2018) which gives beginner design students a hands-on approach to learning optical design with software examples.