History of LED

Sun, 04 Jan 2026 00:00:00 +0900

History of LED (Light Emitting Diode)#

LEDs are used everywhere in the world today — for lighting, displays, and signaling.
Let’s take a look at how the LED was born, refined, and developed.

1907 — “Wait… it just glowed. What was that?”#

1907, in a laboratory in England.
Henry Joseph Round, a radio communication engineer, noticed a strange phenomenon when he passed an electric current through a silicon carbide (SiC) crystal.
“Whoa! It’s giving off light at the contact point!”
Round reported the phenomenon in the journal Electrical World.
But at the time, no one imagined that this faint glow would one day replace the lighting of the world.
The light was simply too weak to seem useful.
And so the seed of the LED was quietly buried.

Nakamura-Shuji on Semonan Book

History of LED

History of LED (Light Emitting Diode)#

1907 — “Wait… it just glowed. What was that?”#