Opto Alignment | Advanced Lens Alignment and Optical Metrology Solutions | Made in the USA
DMI Distance Measurement Technology
The Basics
DMI --> Distance Measurement Interferometer
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Sensing Technology: Infrared Low-Coherence Interferometry (Time Domain mode)
Measurements: Surface position, center thickness and air gap of all optical elements (lenses, cubes, flats, etc.) of an assembly along the optical axis.
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How does it work?
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Light emitted by an infrared Super Luminous Diode (λ = 1.3µm) is coupled into a monomode optical fiber
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The light is split between the measurement arm and the reference arm
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The light coming back from both arms is focused onto a photodetector
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When the optical path lengths of the measurement arm and the reference arm are equal, interference is visible on the photodetector
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High stability mechanics, specific calibration procedure, usage of internal thermal probe and precise encoder index computation enable high accuracy
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