ITO with clarity and roentgenization, metal film such as AI, water-repellent film, and photocatalysis are popular.

ITO or metal film as electrode is frequently used for LCD.

Metal film such as AI is also used for reflection mirror, decoration, electromagnetic wave prevention material.

Primer coat is used as a base to increase adherence of plastic.

There are many cases where the physical and electric characteristics and physical strength are more important than the optical characteristics.

It is important to understand the absorption coefficient when you combine it with an oxidation film and make a filter.