Surface is measured with interferometer and 3D profiler. Low aberration error is achieved by reducing form error.

Measurement: Ultra-precision 3D Profiler (Panasonic - UA3P)
Interferometer: (Zygo - VFA, CGH)
PVr < λ/20

This technology can be applied to the following lenses:
Asphere, Sphere, Cylinder, Freeform, Toroid, Plano (as of Apr., 2014)

Freeform designed by Zernike polynomials