Realization and optimization of planar refracting microlenses by Ag-Na ion-exchange techniques
Autor: | Karl-Heinz Brenner, Jochen Bähr |
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Rok vydání: | 2010 |
Předmět: |
Wavefront
Materials science Fabrication Ion exchange business.industry Aperture Materials Science (miscellaneous) Measure (physics) Astrophysics::Cosmology and Extragalactic Astrophysics Industrial and Manufacturing Engineering Ion Optics Planar Business and International Management business Realization (systems) |
Zdroj: | Applied optics. 35(25) |
ISSN: | 1559-128X |
Popis: | We report the fabrication of planar microlenses with numerical apertures (N.A.’s) of 0.2 by field-assisted Ag–Na ion exchange in glass. To measure the N.A. of microlenses, different definitions can be used. We discuss the issue of measuring the N.A. and suggest an additional definition based on diffraction-limited performance. According to a simple model, the N.A. of a spherical lens is limited by the maximum index difference. Owing to this model, the N.A. for Ag–Na ion exchange is limited to a value of ~0.1. From measurements of microlenses, fabricated by field-assisted ion exchange, we obtained N.A.’s as high as 0.2, providing for diffraction-limited performance within the whole aperture. |
Databáze: | OpenAIRE |
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