Broadband AR coatings typically operate at lower efficiencies than V-Coatings. But, they provide anti-reflective properties over a much wider spectral range. A simple single Layer AR was the first type of Anti Reflection Coating. Although single layers have their uses, we have come a long way and more advanced multilayer systems are typically superior. Thin film thickness is crucial, since Broad Band Anti Reflective coatings have layers as thin as 5nm. With sub nanometer thickness controlling systems we are able to accurately deposit 30 layer ARs that have little "ripple" and match theoretical values just about perfectly.
All Cascade Optical Corporation's Dielectric coatings pass MIL-C-48497 and can be made to pass even the severe abrasion requirements of MIL-C-675. We have a Environmental test Lab department to qualify each and every coating run.
Below are some featured Coatings where customers wanted deviations from the standard, straight forward, visible Broad Band Anti Reflective coating
Astronomers are continually trying to get a better understanding of our Universe and ask for a wider range outside of the visible spectrum. For example, this design was driven by an Astronomer who desired to reduce reflectivity at 370nm, just outside of the traditional Photopic spectrum, in order to study Binary Star Systems
For Military applications we have been asked to push the limits of the traditional visible BBAR and incorporate low reflection at both, common NIR wavlengths, 1064nm and 1550nm
Multi Broadband AR coatings operate over two or more spectral bands. In most cases, it involves visible plus one or more bands in IR. This plot shows a spectral response of a 2-band AR coating designed to operate over, spectral bands, covering 600-700nm and 1450-1650nm. This coating is commonly used in applications where a red lasers or laser diode is used for alignment of telecom S-, C-, and L- band laser lines
Rav<1.25% 280-315, 315-400nm
Rav< 1.25% 425-1100nm