Share Email Print

Proceedings Paper

All-reflective optical power zoom objectives
Author(s): Heinrich Grüger
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Over the past decades zoom lenses have become an important type of objective. Due to their ability to dynamically change magnification or field angle they are being used in many fields of application. Most zoom lenses consist of a number of lenses or lens groups. The magnification can be changed by axial shifting some of these lens groups with a more or less complicated moving function.

However, in principle it should be possible to construct zoom lenses that do not rely on the movement of some of its components. Instead, the change in magnification is achieved by changing the optical power of at least two lenses within the system (optical power zoom - OPZ). Moreover, for broadband applications it is highly favorable to use mirrors instead of lenses due to the absence of chromatic aberrations.

Based on a "Schiefspiegler" approach an all-reflective OPZ objective with a zoom power of three consisting of four mirrors has been designed. Two mirrors are assumed to have a variable radius of curvature for changing optical power. During aberration correction special consideration has been given to the reduction of field curvature, since the optical power change strongly influences field curvature for different zoom positions. The simulation shows adequate image quality for photographic applications over the whole zooming range.

For the realization of such an OPZ objective deformable mirrors with a comparatively large stroke are needed. Before starting a complex development of such devices three setups with different fixed focal lengths were built to prove and evaluate the concept for digital imaging.

Paper Details

Date Published: 3 September 2015
PDF: 13 pages
Proc. SPIE 9580, Zoom Lenses V, 95800H (3 September 2015); doi: 10.1117/12.2188196
Show Author Affiliations
Heinrich Grüger, Fraunhofer-Institut für Photonische Mikrosysteme (Germany)

Published in SPIE Proceedings Vol. 9580:
Zoom Lenses V
Ellis Betensky; Takanori Yamanashi, Editor(s)

© SPIE. Terms of Use
Back to Top