Impact of Beam Shape on Print Accuracy in Digital Light Processing Additive Manufacture

Area of Science:

• Additive Manufacturing
• Photopolymerization
• Optical Engineering

Background:

• Digital Light Processing (DLP) 3D printing uses UV light for photopolymerization.
• Accurate prediction of XY-axis resolution is crucial for microscale feature fabrication.
• Current Gaussian models for UV beam distribution are insufficient for precise microscale printing.

Purpose of the Study:

• To develop a more accurate model for UV beam distribution in DLP 3D printing.
• To improve the prediction of microscale feature formation and XY-axis resolution.
• To provide a method for calibrating beam distribution parameters.

Main Methods:

• Modeling UV beam distribution using a heavy-tailed Lorentzian model.
• Comparing Lorentzian model predictions with Gaussian model predictions.
• Developing a calibration method using single-layer prints to derive model parameters.

Main Results:

• The Lorentzian model accurately predicts small build areas for both positive and negative features.
• The Gaussian model's limitations in predicting microscale polymerization are confirmed.
• A simple calibration method was demonstrated to derive key beam distribution parameters.

Conclusions:

• The heavy-tailed Lorentzian model offers superior accuracy for predicting photopolymerization outcomes in DLP 3D printing.
• Accurate beam distribution modeling is essential for achieving true XY-axis resolution and avoiding errors in microfabrication.
• This work enables improved software prediction of print solidification for voxel-based models.