fig2

Figure 2. Photolithography-based fabrication methods on micro-cylindrical surfaces. (A) Cylindrical direct projection lithography. Reproduced with permission^[40]. Copyright 2018, MDPI; (B) Variable-width slit mask-assisted lithography^[78]. Copyright 2015, SPST; (C) Chromium-coated polymer flexible mask-assisted lithography. Reproduced with permission^[79]. Copyright 2020, IOP Publishing Ltd; (D) Combination of flexible SU-8 photolithographic mask and planar slit mask lithography. Reproduced with permission^[80]. Copyright 2011, Elsevier; (E) Mask-less lithography using high-resolution light beams. Reproduced with permission^[19]. Copyright 2017, John Wiley and Sons; (F) Programmable improved UV lithography system^[81]. Copyright 2013, WORLD SCIENTIFIC PUBL CO PTE LTD. UV: Ultraviolet.