Electrically Tunable Lens (ETL)-Based Variable Focus Imaging System for Parametric Surface Texture Analysis of...

Area of Science:

• Optics and Photonics
• Materials Science
• Surface Metrology

Background:

• Electrically tunable lenses (ETLs) can adjust optical power using electrical signals, enabling depth perception.
• Quantitative surface analysis is crucial in various fields, including pharmaceutical manufacturing.
• Conventional microscopy techniques can be costly and less adaptable for certain analyses.

Purpose of the Study:

• To develop and calibrate an ETL-based imaging system for precise quantitative surface analysis.
• To assess the system's capability in measuring various surface texture parameters.
• To validate the ETL system's performance against established techniques like optical profilometry.

Main Methods:

• System calibration using the Tenengrad operator to ensure high depth resolution and focus plane accuracy.
• Application of the ETL system to measure amplitude, spatial, hybrid, and volume surface texture parameters.
• Validation of results by comparing ETL measurements with those obtained from optical profilometry.

Main Results:

• The ETL system demonstrated a linear relationship between control current and focal height, confirming accurate calibration.
• Measured surface texture parameters (amplitude, spatial, hybrid, volume) showed no statistically significant differences compared to optical profilometry.
• The ETL-based system proved effective for quantitative surface texture analysis.

Conclusions:

• ETL-based imaging systems present a viable, low-cost, and adaptable alternative to conventional microscopy for surface texture analysis.
• The developed system offers high accuracy in measuring depth and surface parameters.
• This technology has potential applications in quality control and research where detailed surface characterization is required.