Influence of printing parameters on overhang structures in micro DLP printing
Martin MICHALAK, Alexandru SOVER, Michael S.J. WALTER
Abstract. Printing of polymer parts via digital light processing (DLP) is an established technology to produce functional complex parts within a short period of time. Within recent years this technology has advanced in even higher geometrical accuracy of the parts since printers and materials were constantly improved. Nowadays, it is possible to print parts with features in micro- (µm) or even nanoscale (nm), opening new fields of application and further improvement to already existing parts. Similar to stereolithography (SLA), DLP applies UV light to harden a photopolymer resin in a layer-by-layer process. This enables printing parts with complex geometries such as cavities, implying the resin can later exit the part. However, DLP has an advantage over other 3D-printing technologies when it comes to creating cavities or the printing of overhang structures in general. Since in DLP the entire layer is hardened at once, less support structure is needed to achieve a uniform, stable layer. In consequence, this opens the design option to print micro cavities without any support structures needed. This paper highlights the process of micro DLP printing of polymer parts, focusing on the influence of the most relevant parameters on the successful print of overhang structures. Therefore, the paper presents an experimental analysis, investigating the effects of relevant printing parameters of an overhang on the dimensional accuracy of the resulting parts. The results show a significant dependence of the bridges (overhangs) on gaps size and curing time, and the deformation of the bridges are in the opposite sides of the parts.
Keywords
Micro Printing, Digital Light Processing, Microfabrication, UV Resin
Published online 1/20/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Martin MICHALAK, Alexandru SOVER, Michael S.J. WALTER, Influence of printing parameters on overhang structures in micro DLP printing, Materials Research Proceedings, Vol. 61, pp 37-42, 2026
DOI: https://doi.org/10.21741/9781644903995-5
The article was published as article 5 of the book Innovative Manufacturing Engineering and Energy
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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