Printing, Characterising, and Assessing Transparent 3D Printed Lenses for Optical Imaging

High-quality lens production has involved subtractive manufacturing methods for centuries. These methods demand specialist equipment and expertise that often render custom high-grade glass optics inaccessible. We aimed to develop a low-cost, accessible, and reproducible method to manufacture high-quality three-dimensional (3D) printed lenses using consumer-grade technology. Various planoconvex lenses were produced using a consumer-grade 3D printer and low-cost spin coating setup, and printed lenses were compared to commercial glass counterparts. A range of mechanical and optical methods are introduced to determine the surface quality and curvature of 3D printed lenses. Amongst others, high-resolution interference reflection microscopy methods were used to reconstruct the convex surface of printed lenses and quantify their radius of curvature. The optical throughput and performance of 3D printed lenses were assessed using optical transmissivity measurements and classical beam characterisation methods. We determined that 3D printed lenses had comparable curvature and performance to commercial glass lenses. Finally, we demonstrated the application of 3D printed lenses for brightfield transmission microscopy, resolving sub-cellular structures over a 2.3 mm field-of-view. The high reproducibility and comparable performance of 3D printed lenses present great opportunities for additive manufacturing of bespoke optics for low-cost rapid prototyping and improved accessibility to high-quality optics in low-resource settings.