عينة شاهد، ناقل الحركة، 1.800-2.000

The polished surfaces are impressively clean under a loupe, and the specified 60-40 scratch-dig held up exactly as promised. I checked the flatness at a couple of wavelengths and it's right at that 1-wave tolerance, which made my transmission measurements feel rock solid.

Ordered these to verify coating runs before committing a full batch, and the parallelism spec held up under our interferometer — no wedge issues at all. Both faces were clean right out of the box, no re-polishing needed.

The 60-40 scratch-dig finish on both sides is noticeably cleaner than the cheaper samples I've ordered elsewhere, and the polished surfaces made alignment under the laser straightforward. Parallelism held up well across the whole aperture too.