Three-dimensional planar alignment of nematic liquid crystal by direct laser writing of nanogratings

Jagodič, Uroš (author), Pišljar, Jaka (author), Jelen, Andreja (author), Škarabot, Miha (author), Muševič, Igor (author)

We demonstrate a new method of aligning liquid crystals along polymer surfaces that are printed vertical to the focal plane using direct laser writing. The method is based on nanogrooves that are imprinted into surfaces of polymer structures and provide robust, reliable, repeatable, and well-controlled alignment patterns. Our results demonstrate that the anchoring strength of a liquid crystal on printed nanogratings is comparable to that of conventional polyimide layers. The advantages are at least 2-fold. First, we can print large vertical areas of well-defined patterns of nanogrooves with uniform anchoring strength, and, second, we can control the azimuthal anchoring strength by adjusting the amplitude and the periodicity of nanogrooves. Printing of alignment nanogrooves on tilted, curved and surfaces of arbitrary shape could be realized using printing protocols based on the principle shown here with potential applications in emerging microphotonic devices based on liquid crystals.

• Language: English
• Keywords: 3D printing, liquid crystals, alignment layer, direct laser writing, displays, microphotonic elements, crystal structure, lasers, layers, organic polymers
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FMF - Faculty of Mathematics and Physics
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: Str. 5970−5977
• Numbering: Vol. 12, iss. 11
• PID: 20.500.12556/RUL-176586
• UDC: 539
• ISSN on article: 2330-4022
• DOI: 10.1021/acsphotonics.5c01342
• COBISS.SI-ID: 254269443
• Publication date in RUL: 04.12.2025

Record is a part of a journal

• Title: ACS photonics
• Shortened title: ACS photonics
• Publisher: American Chemical Society
• ISSN: 2330-4022
• COBISS.SI-ID: 520397849

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: tekoči kristali, 3D tiskanje, laserji

Projects

• Funder: EC - European Commission
• Funding programme: H2020
• Project number: 884928
• Name: Light-operated logic circuits from photonic soft-matter
• Acronym: LOGOS

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P1-0099
• Name: Fizika mehkih snovi, površin in nanostruktur