Liquid crystal displays, the multitude of OLED variants, and most other flat panel display technologies rely on transparent conductive oxides (TCOs) to transport current and to serve as the anode for each light emitting element. Like any thin-film process, it is an important advantage to know the thickness of the layers that form the display. For LCDs, this requires a way to measure the polyimide and LC layers, while for OLEDs it requires measuring the emitting, injecting, and encapsulation layers.
 

Typical coatings are:

OLED‘s

TCO coatings

ITO

Polyimide