Why do light emitting diodes emit different colors of light?

LED has been all over our life, LED display is one of the representative products. Why do light emitting diodes emit different colors of light?

Light emitting diode (LED) is a kind of commonly used light-emitting device, which releases energy by combining electrons and holes. It is widely used in the field of lighting. The colorful lights in the streets are the light emitted by LED.  Light emitting diodes (LEDs) are widely used in modern society, such as lighting, flat panel display, medical devices and so on.

Speaking of LED, people all know it is the abbreviation of LED. LED is made of gallium (GA), arsenic (as), phosphorus (P), nitrogen (n), etc.

When electrons and holes are combined, they can emit visible light, so they can be used to make light-emitting diodes. It can be used as indicator light in circuit and instrument, or form text or digital display. Gallium arsenide diode emits red light, gallium phosphide diode emits green light, silicon carbide diode emits yellow light, and gallium nitride diode emits blue light. Due to its chemical properties, it can be divided into organic light-emitting diode (OLED) and inorganic light-emitting diode (OLED).

LED electronic components appeared as early as 1962. In the early stage, they could only emit low luminosity red light. Later, other monochromatic light versions were developed. Up to now, the light emitted has been all over visible light, infrared ray and ultraviolet ray, and the luminosity has been improved to a certain degree. The use of LE  initially as indicator light, display board, etc., with the continuous progress of technology, LED has been widely used in display and lighting.

Contributed by gmtlight