Torr, millitorr & microns are used to measure high vacuum. A company called Veeco made vacuum gauges, essentially like a light bulb with a long circular filament that had an opening to the vacuum chamber. You had to have a high vacuum in the chamber before you turned the gauge on or the filament would burn out! Someone else hit it right on the nose: it looks like you found an old vacuum metal depostion system, where metals were evaporated onto different types of substrates. I used to do that kind of work / research.