UDC

Universal Display Corporation

A U.S.-based company spearheading phosphorescent OLEDs (PHOLEDs).

UHV

Ultra High Vacuum

Typically defined as gas pressure less than 10−9 mbar. Such vacuum conditions are necessary for deposition techniques like PVD and CVD.

UPS

Ultraviolet Photoelectron Spectroscopy

This is a form of spectroscopy which measures the kinetic energy of electrons emitted from a sample when it is irradiated with high energy ultraviolet radiation. 

UV

Ultraviolet

Ultraviolet light is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light.