Stress Makes Them Bi

Birefringent. Not that there’s anything wrong with that.

In my earlier discussion of polarization, I promised some photos of stress-induced birefringence.

If you have a polarizing filter, you can use an LCD as a polarized light source and view birefringent materials using it as a backdrop. Make the screen as white as possible, and rotate the polarizer until it blocks the light. Then place a birefringent material in front of the screen and look through the polarizer. Cheap clear plastic often will have stress-induced birefringence.

Which is what I did, and is why the background is black. The first photo is the plastic box in which the polarizers were packaged

These next two are the side and top views of a styrene drawer from a small storage cabinet, placed on top of an empty CD spindle.


FAIL

The fastest clock in the world, my ass.

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Oooooh. It displays six whole digits past the decimal. Down to the microsecond. (can you sense the sarcasm?) It’s a display. Just because it reads that many digits doesn’t mean the measurement actually has that precision.

I’ve wanted to get a display that went to the picosecond for the lab, but have it flash 12:00:00.000000000000 the whole time. Add it to the list of my unadopted suggestions.

“I see no progress in this industry. These clocks are no faster than the ones they made a hundred years ago.” — Henry Ford