The development of light-emitting diodes

In 1962, Nick Holoniaco, a researcher at General Electric in the United States, developed the world's first red-emitting diode. In 1963, Holoniaco invented the world's first red-emitting semiconductor laser. This laser diode has now become a key component of CDs, DVDs, laser printers and copiers. Now, people have produced light-emitting diodes that can emit different colors such as yellow, green, blue, and white. Nowadays, giant display screens made of light-emitting diodes are popular all over the world, and the displayed numbers are very clear even during the day. Almost all traffic lights and all indicator lights in cars use light-emitting diodes.

As the name suggests, light-emitting diodes can emit light and are generally represented by the text symbol LED.

LED can convert electrical energy into light energy, once it meets its conduction conditions, it can emit red, green, blue, yellow and other colors of light. It is usually used as indicator light for electrical equipment and low light illumination for special occasions. In fact, the light emitted by LEDs has spread to visible light, infrared light and ultraviolet light.

There are many kinds of light-emitting diodes, the more commonly used ones are monochromatic light-emitting diodes, color-changing light-emitting diodes, flash light-emitting diodes, infrared light-emitting diodes and laser diodes.

The forward working voltage of the light emitting diode (LED) is generally 1.2~2V, and the allowable current is 2~20mA.

At present, LED production technology has progressed rapidly, and the brightness of LEDs has also been greatly improved. With the emergence of white LEDs, they have been widely used in outdoor landscape lighting, indoor lighting, and automotive headlight lighting. In recent years, LEDs have been used for backlighting inside many LCD TVs.