History:LED and LASER
History of LED: LEDs (Light Emitting Diodes) and lasers have both played important roles in the development of modern technology. Here's a brief history of each: LEDs: The first LED was created in 1962 by Nick Holonyak, Jr., a researcher at General Electric. This LED emitted red light and was made from a semiconductor material called gallium arsenide phosphide. In the years that followed, researchers worked to improve the efficiency and color range of LEDs. Green and yellow LEDs were developed in the 1970s, and blue LEDs were invented in the 1990s. The invention of the blue LED was particularly significant, as it allowed for the creation of white light when combined with red and green LEDs. This led to the development of white LED lighting, which is now used in a variety of applications. In the 1990s and 2000s, researchers developed blue and white LEDs with higher efficiency and brightness. These advances made LEDs more practical for use in everyday lighting applications.