A Cost-Effective Controller for the Micro-Stereolithography

A cost-effective micro-stereolithography controller is proposed for fabricating small- to medium-scale 3D components, aimed at reducing the cost of rapid prototyping equipment while maintaining high speed and resolution. The system employs a 405 nm ultraviolet (UV) laser beam from a DLP projection source with adjustable power intensities to cure photopolymer resin. Exposure to a concentrated UV laser triggers a photo-polymerisation reaction, solidifying the resin. Successive cured layers are stacked to create 3D structures. The photopolymer is a methacrylate-based mixture containing oligomers, monomers, and photoinitiators. The set-up’s 3D model is designed using SolidWorks 2023. Laser path tracing is controlled via Arduino programming, ensuring precise movements. Resin layer injection is regulated by valves managed through another Arduino, allowing controlled deposition from the resin reservoir. Coherent Laser FrameWork software is used to control laser intensity. The desired structure depth is achieved by repeating polymerisation cycles. Small-scale 3D structures with rectangular and circular cross sections were fabricated and post-processed. The curing performance varied with laser intensity and exposure time. Optimal results were observed at 2% of maximum laser intensity (2.5 W) with a 50-ms exposure per data point, achieving a layer thickness of 0.35 mm on the z-axis. This system demonstrates cost-efficient precision in 3D printing, offering a scalable solution for rapid prototyping.