What is a Laser interferometer?

A laser interferometer is a device used to analyze the surface shape of a sample. The laser light output from the light source built into the device is split into two by a special mirror called a beam splitter. Then, one is directly applied to the surface of the sample, and the other is reflected once by a beam splitter and then irradiated. At this time, there is a difference in the optical path length between the two laser beams. And when the two waves overlap, the interference pattern changes according to the phase of the waves. Since this interference pattern changes depending on the optical path length, it changes sensitively according to the unevenness of the surface of the sample. Therefore, it is possible to analyze the shape of the sample surface from the interference pattern.

Application of Laser interferometer

Laser interferometer is used for lens surface analysis, etc. Laser interferometers are used to analyze the surface shape of solid samples. For example, it is also used for surface analysis of lenses that require precise shape control, such as camera lenses and contact lenses, and surface shape measurement of DVD discs and glass. Laser interferometers are used for surface analysis in a wide range of fields because they can measure regardless of the shape of the sample, such as planes, spheres, and hemispheres. Not suitable for measuring liquids and rough-surfaced samples On the other hand, it is not often used for measuring liquid samples and unpolished samples because the measurement results are likely to fluctuate due to the effects of external vibration, sample surface fluctuations, and roughness.

※Includes information on some trading companies