Characterization of Planar Dimensional Capabilities in Selective Photopatterning of Diacrylate and Epoxy Monomers

Abstract:

Digital light processing (DLP) can be used as a rapid photopatterning technique with micrometer resolution. To ensure high levels of precision and accuracy, it is required to clearly understand the actual dimensional capabilities in the horizontal plane of a patterning setup. A methodology to assess these capabilities was suggested in this study, and the following parameters were determined: The effective pixel size, the planar dimensional reproducibility, and the dimensional precision in dependence of the angular feature orientation in the x-y plane. Experimental verification of the suggested approach was carried out by using a DLP-based 3D printer. This demonstrated that the nominal pixel size stated in the technical data sheet can deviate from the effective pixel size by more than 1%. Furthermore, dimensional inaccuracies of ±5.1% depending on the feature location within the x-y plane were indicated. The dimensional precision was affected by the angular orientation in relation to the pixel grid, and small errors equivalent to ±0.05 pixels were only achievable with features placed in parallel or diagonal orientation. These results characterize the planar accuracy of DLP equipment and help minimize dimensional errors in the direct digital manufacture of microchannel and strut-like patterns.

• Periodical: Key Engineering Materials (Volume 753)
• Pages: 200-205
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.753.200
• Online since: August 2017
• Authors: Robert Bail*
• Keywords: Cure Width, Dimensional Accuracy, DLP, Micropatterning, Photopolymerization

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