Why Blue LED Lights Were So Much More Difficult to Create Than Red or Green LEDs
Derek Muller of Veritasium explained why red and green LED lights were relatively simple to make, but blue LED still remained quite elusive. In fact, red and green were already being used for years before Japanese researcher Shuji Nakamura unlocked the key to the blue LED in the face of growing pressure from his employer.
The blue LED was supposed to be impossible—until a young engineer proposed a moonshot idea.