Japan’s AIST Introduces Contact‑Free Instrument Measuring Curved Optics to Two‑Nanometer Accuracy

Scientists from Japan’s National Institute of Advanced Industrial Science and Technology (AIST) disclosed a novel device that can determine the absolute surface topography of curved optical parts with a two‑nanometer precision, without any physical contact with the sample.

The apparatus uses an enhanced interferometric technique that pits the light reflected off the test surface against a calibrated reference wavefront. Examining the resulting interference fringes enables the system to rebuild the three‑dimensional geometry of a mirror or lens and detect variations down to only a few atomic layers.

Conventional methods for evaluating curved optics typically depend on tactile probes or indirect approaches that can add uncertainty, particularly with fragile or highly curved surfaces. The AIST tool avoids these drawbacks, providing direct, absolute readings that are repeatable and free from mechanical interference.

This level of precision is set to aid numerous high‑tech industries. Astronomical telescopes, which rely on meticulously shaped mirrors to collect faint starlight, could achieve better alignment and performance. Likewise, semiconductor lithography, laser fabrication and sophisticated imaging equipment would benefit from stricter quality control of their optical components.

AIST boasts a longstanding record of innovation in photonics and metrology, and this advancement leverages its established skill in interferometry and surface measurement. The research group intends to test the system on a range of mirror dimensions and curvatures, and to investigate automation that could embed the device into manufacturing workflows.

Looking forward, the institute plans to hone the technology further, aiming for even higher resolution and quicker data capture. Should these efforts succeed, the contact‑free profiler may become a staple for producers striving to extend optical precision while reducing risk to fragile parts.