Two-wavelength sinusoidal phase/modulating laser-diode interferometer insensitive to external disturbances

Area of Science:

• Optics and Photonics
• Metrology

Background:

• Interferometry is sensitive to environmental factors like wavelength fluctuations and mechanical vibrations.
• Traditional interferometers often require complex stabilization techniques.

Purpose of the Study:

• To develop a two-wavelength laser-diode interferometer robust against external disturbances.
• To enable accurate measurements of distance, rotation angle, and surface profiles.

Main Methods:

• Utilizing a two-wavelength laser-diode system with an equivalent wavelength of 152 microm.
• Implementing a feedback control system to manage laser diode injection current for sinusoidal phase-modulating interferometry.

Main Results:

• Demonstrated insensitivity to laser wavelength fluctuations and mechanical vibrations.
• Achieved high accuracy in distance, rotation angle, and surface profile measurements.

Conclusions:

• The developed interferometer offers a stable and accurate solution for precision metrology.
• This technique enhances the reliability of interferometric measurements in challenging environments.