Last year’s nobel prize went to three people who developed blue leds in 1990’s. red and green led’s were developed much earlier but none of the developers of red or green leds have won the nobel prize. this is partly because you need all three colors, red, green and blue to create white light. however, this statement is not fully correct, considering that some of the white leds use only blue leds encapsulated by a phosphor coated bulb to generate white light. can you make white leds out of red or green leds by utilizing phosphors? explain.