Automated brightfield layerwise evaluation in three-dimensional micropatterning via two-photon polymerization.

Area of Science:

• Advanced Materials Science
• Microfabrication Technologies
• Optical Engineering

Background:

• Two-photon polymerization (TPP) is a key 3D fabrication method for submicron precision.
• Characterizing the quality of TPP-fabricated structures, especially complex internal features, remains a significant challenge.
• Existing methods often lack in situ monitoring capabilities for real-time quality assessment.

Purpose of the Study:

• To introduce a facile and accurate in situ method for monitoring TPP fabrication quality.
• To enable real-time quality assessment of complex microstructures during the TPP process.
• To facilitate high-fidelity manufacturing of sophisticated TPP-based microstructures.

Main Methods:

• Developed an automated brightfield layerwise evaluation technique.
• Utilized sequentially acquired brightfield images during the TPP writing process.
• Employed background subtraction and image processing to extract layered spatial features for quality assessment.

Main Results:

• Successfully implemented an in situ monitoring and quality assessment approach for TPP.
• Experimentally validated the method by fabricating a fibrous tissue scaffold.
• Achieved an overall system-adjusted fidelity of 87.5% in situ for the printed scaffold.

Conclusions:

• The automated brightfield layerwise evaluation technique provides a simple-to-implement solution for TPP quality control.
• The method is readily adaptable to most TPP systems.
• This approach has the potential to significantly improve the manufacturing quality of complex microstructures via TPP.