Industrial Vat-Photopolymerisation Architectures: SLA, DLP, LCD/MSLA and Continuous Printing

Industrial vat photopolymerisation includes multiple exposure and interface architectures that must not be collapsed into a single `SLA` parameter space. Laser-scanned stereolithography delivers a moving optical spot; digital light processing projects a micromirror image; LCD/MSLA masks a light-engine field; and continuous routes maintain an inhibition or mobile liquid interface to reduce discrete separation and recoating pauses. This qualitative engineering review follows each route from released resin to accepted component. It examines resin conditioning, spectral and spatial light delivery, working curves, voxel and feature formation, separation, resin renewal, heat and mass transport, supports, drainage, washing, post-cure, shrinkage, surface state, safety, full-cell throughput and change control. Primary and interlaboratory studies demonstrate that nominal wavelength, pixel pitch, exposure time or scalar radiant exposure cannot independently determine cured geometry or network state. Continuous extraction can remove one class of mechanical pause while introducing interface-stability, flow, viscosity and thermal constraints. Post-cure can strengthen one resin while worsening dimensional fidelity, and whole-layer exposure does not eliminate geometry-dependent separation or downstream labour. The proposed selection gate requires architecture-specific metrology, state-labelled evidence and acceptance after the qualified post-process. Volumetric/tomographic printing, two-photon polymerisation, material jetting, ceramic/metal green-body conversion and construction-scale applications are outside scope.

3Dresyns Engineering Review ER-142, version 0.2. Provider-neutral technical review.