is a technical means to reduce reflection and increase light absorption of solar cells and thus increase its performance.

The Anti Reflective Coating on a solar cells helps to increase the amount of light absorbed into the cell.  This anti reflective coating is very much needed as the reflection of a bare silicon solar cells is over 30%.

For the thin AR Coating, silicon nitride or titanium oxide is used. When the anti-reflection coating is left off, the cells will have a natural dark grey color. The color of the solar cell can be changed by varying the thickness of the anti-reflection coating. Anti-reflection coatings on solar cells are quite similar to coatings used on other equipment such as camera lenses.

Reflective coating on thin film solar

More info on Anti-reflective coating here

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