Microlens characterization by digital holographic microscopy with physical spherical phase compensation

Area of Science:

• Optics and Photonics
• Microscopy Techniques

Background:

• Digital holographic microscopy (DHM) is a powerful tool for optical metrology.
• Conventional DHM systems often suffer from inherent wavefront aberrations.
• These aberrations complicate accurate phase measurements of micro-optical components.

Purpose of the Study:

• To develop a digital holographic microscopy system for aberration-free characterization of microlenses.
• To leverage fiber optics for an improved reference wave in DHM.
• To achieve direct quantitative phase measurement without complex numerical compensation.

Main Methods:

• Utilized a digital holographic microscopy system incorporating fiber optics.
• Employed light from a single-mode fiber as the recording reference wave.
• Optimized optical setup alignment using numerical reconstruction software to remove off-axis tilt.

Main Results:

• Demonstrated a DHM system immune to inherent wavefront aberrations.
• Achieved a quasi-identical object and reference wavefront using a specific fiber optic setup.
• Successfully obtained direct quantitative phase of microlenses without complex numerical compensation.

Conclusions:

• The developed fiber-optic-based DHM system effectively eliminates wavefront aberrations.
• This method provides a simplified and accurate approach for microlens characterization.
• The system enables direct quantitative phase imaging, enhancing metrological capabilities.