25 mm Reference Sphere

The f/0.51 numerical aperture on this sphere really helped us get cleaner wavefront data during calibration, and the 1/10 wave performance held up exactly as expected. It's a solid piece of glass for the price.

The 1/10 wave surface quality on this 25 mm sphere is exactly what I needed for repeatable alignment checks, and the readings stay consistent run after run. The f/0.51 aperture and 40% reflectivity match the spec sheet perfectly, no surprises.

Swapped in this 25 mm sphere for the worn one on our interferometer and the fringe pattern cleaned right up. The 1/10 wave spec holds up in practice, and the 40% reflectivity gives a nice bright return without fiddling with the source.