Interferometers are essential measurement tools for the production and quality control of optical components and systems. Their applications range from testing the flatness and sphericity of surfaces to measuring radii and testing the performance of optical systems.

Technical mass products with flat surfaces specified to better than 0.1µm over a few cm are produced by millions per month.The production processes are lapping & polishing – and, increasingly more often, micro-machining; 90% have diameters under 50mm.ISO 9000 requires tight inspection often 100%.The most common tool for this is The Interferometer.An esteemed value to engineers as does the stethoscope for the medical practitioner.