Back when I was a grad student at NIST, we had a large frame argon ion laser that put out 10-15 watts of green light that we then used to pump a Ti:Sapph laser to produce the infrared light we used for laser cooling. This particular type of laser had a small design flaw– the energy needed for laser operation was pumped into the medium by exciting a plasma discharge in the tube using a high-voltage filament, which was coiled around the beam line. Over time, the filament would soften slightly from the heat of the plasma, then droop into the beam line, and mess up the laser mode, rendering it useless.
There was one stretch, around 1997, when we went through three laser tubes in one year (two of them from the filament droop problem, the third from something unrelated). As the tubes cost something like $20,000, this was a non-trivial matter (this was before we were working in the Infinite Money Limit). When the third one went, we had Bob the laser tech out to confirm the problem, and he suggested a simple solution that kept the tube running for another six months:
He flipped the tube upside down. The filament became a problem because it sagged down into the beam, but rolling the tube over switched “up” and “down,” and it took some time for the filament to start sagging in the other direction enough to cause a problem. Flipping the tube put the high-voltage leads on top of the tube, instead of on the bottom, but that wasn’t a problem unless you opened the case, and other than that, everything worked just fine.
Bob told us that he had flipped a tube three times for some other research group, and that each flip cut the working time roughly in half– the sdcond flip bought three months, the third a bit under two. By the time that our tube started to be a problem again, we had arranged for a replacement, so we never tested that, but it’s always struck me as a neat and low-tech solution to a high-tech problem.
Which brings me around to the “Dorky Poll” part of this:
What’s your favorite example of a low-tech solution to a high-tech problem?
Science abound with ingenious little tricks that people use to get around the quirks of their sophisticated apparatus. What’s your favorite?