PPolySim OS

Thin-Film / AR Coating

Why do camera lenses have a purple sheen, and soap bubbles swirl with color? A film just a fraction of a wavelength thick makes light interfere with itself.

Thin-Film / AR CoatingLive

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Presets

Coat glass with a film a quarter-wavelength thick and its two reflections cancel by destructive interference — an anti-reflection coating. It works best at one wavelength (the reflectance dips to near zero there), giving camera lenses and glasses their faint purple sheen. The same physics makes soap bubbles and oil slicks shimmer with color.

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Data Inspector

Ideal thickness (550nm)100 nm
Min reflectance1.26%
Film index1.38

Governing equation

Reading this result: At 100 nm the film is almost exactly quarter-wave for 550 nm, so green-light reflection is nearly cancelled — an ideal AR coating.

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How it works

When light reflects off the two surfaces of a thin film, the two waves interfere. A quarter-wavelength-thick film makes them cancel, forming an anti-reflection coating that all but eliminates reflection at one wavelength — giving lenses their faint tint. Varying film thickness produces the shifting colors of soap bubbles and oil on water.

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Frequently asked questions

Is this thin film anti-reflection coating tool really free?
Yes. Thin-Film / AR Coating runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.