GE 1950s vacuum tube laser repair

Earliest commercial laser welding application. Used to illustrate that any new heat source gets tried for welding.

When Sir Humphry Davy discovered the electric arc in 1805 or thereabouts, one of the first things he did was try to weld with it. The first commercial application I've ever heard of with a laser was General Electric repairing vacuum tubes in the mid-1950s. The laser had just sort of been invented. Back then they didn't have high-power transistors; they used vacuum tubes. Some of these were very expensive, costing hundreds of dollars apiece in 1955, '56 dollars. Sometimes they'd get a bad weld in those little components and they'd have to break the seal, fix it, and put it back together. With the laser they could go in and hit that little post of tungsten or molybdenum, cause one of them to get soft, and with gravity as their aid they could cause the two to touch one another. Then they'd go in with a higher-power pulse and weld them together without breaking the vacuum seal in the glass, because the lasers would go right through the glass if you had the right kind of laser.