A See‑Through GaAsP LED From the Dawn of Visible Light #tech #engineering #led

Added: 2026-05-21

[00:00:00]Notice how the whole case on this LED is crystal clear, not just the lens. That's because this wasn't a production LED.

[00:00:07]It's an engineering sample. Bell Labs and Western Electric built these cases 100% transparent so you can see the die in action. You can see the bond wire, the square mesa. And once we get under the scope, you can even see the starburst design. This is the only one I've ever seen and it's not marked.

[00:00:24]But the square mesa and starburst design contacts are both fully described in the Western Electric patents from 1970 and 1972.

[00:00:33]I don't think Western Electric ever made consumer LEDs, but they made millions for their telecommunication equipment.