INVITED: AR Coatings for Microscopes Relating to Life-Science Applications

High resolution images for life science applications are given by modern confocal laser fluorescence microscopes. The fluorescence light in some applications is extremely low in signal. Therefore optical components with very high transmittance over a wide spectral range are needed. Both, wide spectral range and high transmittance, meaning very low remaining reflectance, leads to comprehensive coating designs with a higher number of layers while usually some of these layers are very thin. It is a challenge for typical box coaters with PVD-evaporation technique to produce such coatings with reliable results.

By using special vacuum components for improved process conditions it is possible to overcome some common process uncertainties that affect in particular the reproducibility of the thin film thicknesses. In this work some basic analysis and examples are shown. Experimental results will be presented that show the opportunities of the mentioned vacuum components and their application for very low remaining reflectance of broadband antireflection coatings for life science applications.