Japanese Lab Unveils Non‑Contact Tool That Maps Curved Mirrors Within Two Nanometers

Researchers at Japan's National Institute of Advanced Industrial Science and Technology (AIST) have announced a new instrument capable of measuring the absolute surface profile of curved optical components with a precision of two nanometers, all without physically touching the specimen.

The device employs a refined interferometric approach that compares the light reflected from the test surface with a calibrated reference wavefront. By analysing the resulting interference pattern, the system can reconstruct the three‑dimensional shape of a mirror or lens and resolve deviations as small as a few atomic layers.

Traditional techniques for assessing curved optics often rely on tactile probes or indirect methods that introduce uncertainties, especially when dealing with delicate or high‑curvature surfaces. The AIST instrument sidesteps these limitations, delivering direct, absolute measurements that are both repeatable and free from mechanical disturbance.

Such accuracy is poised to benefit a range of high‑technology sectors. Astronomical telescopes, which depend on precisely figured mirrors to focus faint light from distant objects, could see improved alignment and performance. Similarly, semiconductor lithography, laser manufacturing and advanced imaging systems stand to gain from tighter quality control of their optical elements.

AIST has a long history of pioneering work in photonics and metrology, and this development builds on its existing expertise in interferometry and surface metrology. The research team plans to validate the system across a variety of mirror sizes and curvatures, and to explore automation that would integrate the tool into production lines.

Looking ahead, the institute aims to refine the technology further, targeting even finer resolution and faster data acquisition. If successful, the non‑contact profiler could become a standard asset for manufacturers seeking to push the limits of optical precision while minimizing risk to delicate components.