The keen Lande immediately thought of the significance of using silicon carbide as a new light source, but its light was so weak that only blind people could endure reading in such light. After several years of hard work, Lande finally gave up on the research. Fast forward a decade, and in the late 1920s, two German scientists took the research out of the scientific "garbage heap" again, using instead of silicon carbide, zinc sulfide and copper Extracted from yellow phosphorus.

Like silicon carbide, yellow phosphorus also has a special physical structure that can emit visible light when excited by electrons. These substances are collectively referred to as "light emitting diodes", or LEDs. Unfortunately, the two scientists were too optimistic about the situation, and after spending a lot of time and energy, they did not overcome the excessively dim light in the end. Maxima is easy to find, but Bole is rare, and the beautiful light of LED is buried again.

In the blink of an eye, in the 1950s, with the development of the times and the advancement of technology, major technology companies have devoted themselves to the research of LED lights. After the unremitting efforts of many people, finally on August 8, 1962, General Electric Company of the United States developed the world's first practical red LED. After another 10 years, mankind produced the first yellow LED, and the brightness of the LED light at this time was increased by 10 times. You may have noticed that LED lights, depending on the material, can only emit a single color of light.

Monument home diodes can emit red light, silicon carbide diodes can emit yellow light, and later people discovered that phosphide home diodes can emit green light, but what humans need most is white light. If you want to synthesize white light, it is not enough to rely on red light, yellow light, and green light. People also need blue light.