Light-emitting diode phosphors provide more diffuse light, which is desirable for many applications. Remote phosphor designs are also more tolerant of variations in the LED emissions spectrum. A common yellow phosphor material is cerium-doped yttrium aluminium garnet (Ce:YAG). White LEDs can also be made by coating near-ultraviolet (NUV) LEDs with a mixture of high-efficiency europium-based phosphors that emit red and blue, plus copper and aluminium-doped zinc sulfide (ZnS:Cu, Al) that emits green. This is a method analogous to the way fluorescent lamps work. This method is less efficient than blue LEDs with YAG:Ce phosphor, as the Stokes shift is larger, so more
Light-emitting diode In this case, the bond wire(s) are attached to the ITO film that has been deposited in the LEDs. The YAG phosphor in the LED's encapsulation compound is why white LEDs look yellow when off. Some LED light bulbs use a single plastic cover with YAG phosphor (remote phosphor) for several blue LEDs instead of using a diffuser and single chip white LEDs. Remote phosphor LED light bulbs may have behind the plastic cover a white plastic reflector. Others shape the remote phosphor as a dome, or sphere, and place it atop a single PCB containing blue LEDs; this assembly