The Origin of “Excimer”
The name “excimer laser” is derived from the terms “excited” and “dimers,” molecules composed of two atoms that only bind together in an excited electronic state.
A modern medical breakthrough that has touched millions of people started with some turkey left over from Thanksgiving Day dinner, November 26, 1981.
Three researchers at the IBM ® Thomas J. Watson Research Center in Yorktown, New York—Samuel Blum, Rangaswamy Srinivasan and James J. Wynne—had been exploring new ways to use the excimer laser that had been recently acquired by their laser physics and chemistry group. Blum was an expert in materials science; Srinivasan was a photochemist with 21 US patents to his name; and Wynne was a physicist, who was the manager of the group at IBM.
The excimer laser uses reactive gases, such as chlorine and fluorine, mixed with inert gases, such as argon, krypton and xenon. When electrically excited, the gas mixture emits energetic pulses of ultraviolet light, which can make very precise, minute changes to irradiated material, such as polymers.
“We wondered if the excimer laser could so cleanly etch polymeric material, what would happen if we tried it on human or animal tissue?” remembers Wynne. “What really broke things open, after all the talk of what kind of tissue we would use, was that Sri brought his Thanksgiving turkey leftovers into the lab the day after Thanksgiving in 1981,” said Wynne. “He used the excimer laser at 193nm to etch a pattern in whatever bone, cartilage or meat was on the tissue sample … I had this moment of eureka, we have a new form of surgery! By using the ultraviolet light of the excimer laser, we were getting an extremely clean cut, with no evidence of damage to the surrounding tissue.”
Instead of burning living matter, each laser pulse disrupted the molecular bonds in a very thin layer on the surface of the tissue, effectively disintegrating it, leaving no observable collateral damage to the underlying or adjacent tissue. To demonstrate this effect to the medical technology field in a dramatic way, the team produced a hi