كرة نقل 4 بوصة، F/7.1، 1/20 موجة - مطلي

The 1/20 wave surface accuracy shows up immediately in the interferogram — fringes are dead straight across the full aperture. That F/7.1 cone mates perfectly with my current setup, and the coating’s holding up well so far. For the price, this is a solid addition to the bench.

I was really impressed by how clean the wavefront on this transmission sphere is — the 1/20 wave accuracy made a noticeable difference in our test setup. It also fits perfectly into our existing interferometer without any adapters needed.

Swapped this in for our older reference sphere and the fringe contrast on our Fizeau setup jumped immediately — those clean, straight fringes make alignment so much less fiddly. The F/7.1 focal ratio fits our interferometer nicely and the coating holds up fine under our laser. Genuinely glad we upgr