How to measure the wavelength of a laser diode
The wavelength of a laser is measured in meters (nanometers, micrometers, millimeters, etc. When monochromatic light passes through a diffraction grating, it produces a characteristic diffraction pattern due to the interference of light waves. In this document we'll describe a method for measuring the line width of single longitudinal mode lasers. It is a key procedure of measuring the diode laser wavelength in the wavelength modulation spectroscopy (WMS) technique since it determines the selection of specific modulation amplitude and frequency and thus the overall accuracy of the WMS technique.
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