Mirror cleaning

[Larry 1969]

All good information here. I will pay attention to the clips before I take it apart.

Larry

[KathyNS]

I've read about "pinched optics" and never really understood it. Are they saying that you actually distort the glass? That's hard to believe...

It's true. The wavelength of light is a range centred around 500 nm. Most commercial mirrors are accurate to around 1/8 wave, which is a tolerance of 60 nm. So any movement of the surface more than 60 nm (or likely considerably less) is a distortion, and will affect optical performance.

Remember also that glass is a liquid. Strange as it seems, because it is an extremely viscous liquid, but it is not crystalline, as true solids are, so it can be deformed.