F/35 Converger 4"

My interferometer readings were noticeably cleaner after swapping to this 4-inch converger, and the 1/10 wave surface holds up well during testing sessions.

The 1/10 wave PV spec is what sold me, and it holds up—collimated output is clean and stable across the full 4-inch aperture. Fit and finish are solid, and it threads on without any fuss.

The 4-inch aperture is just the right size for my bench setup, and the 1/10 wave PV figure gives me real confidence in the wavefront. Hooked it up to my interferometer and the fringes were clean right out of the box.