Repository hosted by TU Delft Library

Home · Contact · About · Disclaimer ·

Manufacturing of high precision aspherical and freeform optics

Publication files not online:

Author: Hoogstrate, A.M. · Drunen, C. van · Venrooy, B.W.H. van · Henselmans, R.
Institution: TNO, Stieltjesweg 1, 2628 CK, Delft, Netherlands
Source:Modern Technologies in Space- and Ground-Based Telescopes and Instrumentation II, 1-6 July 2012, Amsterdam, Netherlands, 8450
Proceedings of SPIE - The International Society for Optical Engineering
Identifier: 469700
ISBN: 9780819491510
Article number: 84502Q
Keywords: Electronics · Asphere · Freeform · NANOMEFOS · Polishing · SPDT · High Tech Systems & Materials · Industrial Innovation · Mechatronics, Mechanics & Materials Physics & Electronics · IM - Instrurment Manufacturing OPT - Optics · TS - Technical Sciences


Aspherical and freeform optical elements have a large potential in reducing optical aberrations and to reduce the number of elements in complex high performance optical systems. However, manufacturing a single piece or a small series of aspherical and freeform optics has for long been limited by the lack of flexible metrology tools. With the cooperative development of the NANOMEFOS metrology tool by TNO, TU/e and VSL, we are able to measure the form of aspheres and freeforms up to 500 mm in diameter with an accuracy better than 10 nm rms. This development opened the possibility to exploit a number of iterative, corrective manufacturing chains in which manufacturing technologies such as Single Point Diamond Turning, freeform grinding, deterministic polishing and classical polishing are combined in an iterative loop with metrology tools to measure form deviation (like CMM, LVDT contact measurement, interferometry and NANOMEFOS). This paper discusses the potentials, limitations and differences of iterative manufacturing chains used by TNO in the manufacturing of high performance optics for astronomical purposes such as the manufacturing of the L2 of the Optical Tube Assembly of the four laser-guide star facility of the ESO VLT, Manufacturing of Aluminum freeform mirrors for the SCUBA-2 instrument. Based on these results we will give an outlook into the new challenges and solutions in manufacturing high-precision optics. © 2012 SPIE.