The invention of the LCD (liquid crystal display) is credited mainly to two key figures: George H. Heilmeier and James L. Fergason.

• George H. Heilmeier, working at RCA Laboratories in the 1960s, developed the first working LCD using the dynamic scattering mode (DSM). He is often credited as the inventor of the LCD and was inducted into the National Inventors Hall of Fame for his contributions.

• James L. Fergason is credited with discovering the twisted nematic (TN) field effect of liquid crystals in 1969, which is the scientific basis for modern LCDs. He made the first operating LCDs using this effect in 1970 and held many patents fundamental to the industry.

Thus, Heilmeier pioneered the first practical LCD technology, while Fergason advanced the display with the twisted nematic effect that enabled low power and better visual quality, shaping today's LCDs. In summary, George H. Heilmeier invented the first working LCD, and James L. Fergason invented the modern form of LCD by discovering and implementing the twisted nematic effect.