Note: Laser wavelength precision measurement based on a laser synthetic wavelength interferometer

Area of Science:

• Optics and Photonics
• Metrology
• Laser Physics

Background:

• Precise laser wavelength determination is crucial for various scientific and industrial applications.
• Existing methods may face limitations in accuracy or range for certain laser types.

Purpose of the Study:

• To present a new method for high-precision laser wavelength measurement using a laser synthetic wavelength interferometer (LSWI).
• To demonstrate the capability of the LSWI to accurately determine unknown laser wavelengths, even those very close to a reference wavelength.

Main Methods:

• Utilizing a laser synthetic wavelength interferometer (LSWI) that relies on the linear relationship between measurement and reference arm displacements.
• Measuring the synthetic wavelength by detecting phase coincidences of two interference signals.
• Deriving the unknown laser wavelength from the measured synthetic wavelength and a known reference wavelength.

Main Results:

• Experimental determination of wavelengths for an external cavity diode laser and two He-Ne lasers.
• Achieved a relative uncertainty on the order of 10(-8) for the measured wavelengths.
• Demonstrated the method's effectiveness in measuring wavelengths close to the reference wavelength, yielding a larger synthetic wavelength.

Conclusions:

• The proposed LSWI method offers a robust and accurate approach for laser wavelength metrology.
• The technique provides high precision, suitable for demanding applications requiring precise wavelength control and measurement.
• The LSWI method simplifies the determination of wavelengths close to a reference, overcoming potential limitations of other interferometric techniques.