Vibration-immune high-sensitivity profilometer built with the technique of composite interferometry.

Area of Science:

• Optical engineering
• Metrology
• Surface science

Background:

• Accurate surface characterization is crucial for material science and manufacturing.
• Existing profilometry techniques face limitations in simultaneously measuring amplitude and phase information.
• Environmental perturbations and scanning components can affect measurement accuracy.

Purpose of the Study:

• To develop a prototype profilometer capable of simultaneously measuring surface amplitude and phase information.
• To enhance measurement accuracy and speed through a novel composite interferometry design.
• To achieve vibration immunity for high-sensitivity surface profiling.

Main Methods:

• Utilized composite interferometry, combining Michelson and Mach-Zehnder interferometers.
• Implemented a phase compensation mechanism by subtracting interferogram phases.
• Incorporated an additional optical delay component to boost interference signal sensitivity.
• Designed a robust optical system to improve measurement speed and accuracy.

Main Results:

• Successfully built a prototype composite interferometry profilometer.
• Achieved simultaneous measurement of surface amplitude and phase distribution.
• Demonstrated a phase compensation mechanism for high-sensitivity surface profiling.
• The prototype exhibited a displacement sensitivity of 0.64 nm.
• Significantly improved measurement speed and accuracy compared to conventional methods.

Conclusions:

• The developed composite interferometry profilometer offers simultaneous amplitude and phase surface measurement capabilities.
• The phase compensation mechanism and robust design lead to enhanced sensitivity, speed, and accuracy.
• The vibration-immune prototype demonstrates potential for advanced surface metrology applications.