The 1977 model was monochromatic by design. The efficient Blue LED completing the color triad, did not arrive for another decade. Large displays now use high - brightness diodes to generate a wide spectrum of colors. It took three decades and organic light - emitting diodes for Sony to introduce an OLED TV, the Sony XEL - 1 OLED screen which was marketed in 2009. Later, at CES 2012, Sony presented Crystal LED, a TV with a true LED - display (in which LEDs are used to produce actual images rather than acting as backlighting for other types of display, as in LED - backlit LCDs which are commonly marketed as LED TVs).
when did led tv's first come out
1977