deskthority

I picked it up, new, at the recycler, thinking it was a drill bit, but it is not. It is 13 cm long, and has a light or lens of some sort at the small end. The large end is about 3/4". It appears to be made of stainless steel. Engraved on it is QD90-6722.

Pics are here: https://plus.google.com/photos/10611125 ... banner=pwa

I added another pic, showing the larger end. There is a lens of some sort inside, and light shines through to the lens at the smaller end.

something like this: http://en.wikipedia.org/wiki/Refractometer?

I don't know, there is no flip up cover with a scale, nor anyplace to attach one?

It might just be a simple "plug and play" optical sensor for a machine.

There is a mirror at the end, right?

My guess is that it is a part of a laser cutter. QD would stand for Qiang-Da, a maker of CNC-controlled machines such as laser cutters and routers.
It could also be part of an alignment mechanism of some sort, maybe to just shine an alignment beam.

No mirror. Someone said that it is a tool for dentistry, for use on dental imaging systems. Another said that it is a tip for an endoscopic inspection device.

The strange things that turn up at recyclers!