What primary factor stalled the full realization of LED lighting for nearly three decades after the red LED was invented?

Answer

The lack of a practical blue LED created a "color gap."

Achieving efficient green and, critically, blue light proved exceptionally difficult, creating a 'color gap' that prevented engineers from mixing red, green, and blue (RGB) to produce white light for general illumination.

What primary factor stalled the full realization of LED lighting for nearly three decades after the red LED was invented?

#Videos

History of LED Lights - How do they Work? - YouTube

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