Share Email Print

Proceedings Paper

Coherence management for microlens laser beam homogenizers
Author(s): Lars Erdmann; Matthias Burkhardt; Robert Brunner
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

We suggest an optical system for beam homogenization and speckle reduction of spatially highly coherent Laser beams. The new method is applicable to laser beams with moderate temporal coherence. Based on the finite temporal coherence the spatial coherence is reduced prior to the homogenizer component. The new design was experimentally tested for ArF - Excimer laser at 193nm. For this Deep UV application we used silicon micromirrors in combination with fused silica microlenses with a pitch of 150 μm . In contrast to former fly's eye homogenizers for laser beams the new method employs a large number of sub-apertures even for lasers with high spatial coherence. This results in a speckle free and uniform intensity distribution in the target plane. Furthermore the pupil filling can be increased drastically. Experimental results for a DUV microscopy application are presented and discussed.

Paper Details

Date Published: 16 August 2002
PDF: 10 pages
Proc. SPIE 4775, Modeling and Characterization of Light Sources, (16 August 2002); doi: 10.1117/12.479646
Show Author Affiliations
Lars Erdmann, Carl Zeiss Jena GmbH (Germany)
Matthias Burkhardt, Carl Zeiss Jena GmbH (Germany)
Robert Brunner, Carl Zeiss Jena GmbH (Germany)

Published in SPIE Proceedings Vol. 4775:
Modeling and Characterization of Light Sources
C. Benjamin Wooley, Editor(s)

© SPIE. Terms of Use
Back to Top