Single-Shot 3D Topography of Transmissive and Reflective Samples with a Dual-Mode Telecentric-Based Digital...

Area of Science:

• Optical Engineering
• Microscopy
• Holography

Background:

• Common-path digital holographic microscopy (DHM) offers robustness against environmental fluctuations due to self-interference.
• A key limitation of common-path DHM is the overlay of sample information replicas, restricting its use to sparse samples and hindering material science applications.
• Existing solutions like limiting the field of view or using spatial filters are often suboptimal.

Purpose of the Study:

• To implement and optimize optical spatial filtering in a common-path DHM system using a Fresnel biprism.
• To overcome the replica overlay issue, thereby expanding the applicability of common-path DHM.
• To develop and demonstrate the first dual-mode common-path DHM system.

Main Methods:

• Implemented optical spatial filtering using a Fresnel biprism in a common-path DHM setup.
• Analyzed optimal pinhole size by evaluating frequency content of reconstructed phase images from a star target.
• Quantified system accuracy and noise sensitivity across different pinhole sizes.
• Developed and experimentally validated a novel dual-mode common-path DHM system.

Main Results:

• Successfully implemented optical spatial filtering to mitigate replica overlay in common-path DHM.
• Determined optimal pinhole size for spatial filtering based on frequency analysis and noise sensitivity.
• Demonstrated the feasibility and performance of the first dual-mode common-path DHM system.
• Experimentally validated the system with both transmissive and reflective microscopic samples.

Conclusions:

• Optical spatial filtering with a Fresnel biprism effectively overcomes the limitations of common-path DHM.
• The developed dual-mode system significantly enhances the versatility and applicability of common-path DHM, particularly in material science.
• This advancement paves the way for broader adoption of robust DHM techniques in various imaging applications.