3D laser lithography is a powerful technology to manufacture free-form micro- and nano-optical components. However, practical applications of these components are limited due to lack of knowledge of their optical resilience to intense femtosecond laser radiation, especially in the case of complex-shaped 3D structures. In this report, 3D woodpile structures were fabricated using 3D laser lithography in order to evaluate their laser-induced damage threshold (LIDT). For that S-on-1 testing method was performed on fabricated polymeric nanolatices showing their resilience to femtosecond radiation in the fluence range from tens to hundreds mJ/cm<sup>2</sup>. Furthermore, numerical modeling and experimental investigation were employed to deduce if the chosen geometry provided any photonic properties that could yield a change in the LIDT.
The spread of micro-optical elements fabrication by femtosecond 3D nanolithography is limited due to lack of available optically resilient photopolymers. We have conducted S-on-1 laser-induced damage threshold (LIDT) measurement experiment with two different photopolymers, which demonstrated varying damage probability distribution after which suitable linear approximation technique was not evident. Moreover, different optical damage mechanisms were present during laser irradiation of diverse photopolymers that featured different chemical composition and physical properties. Seeking to determine reliable LIDT evaluation method which would provide trustworthy results for all the investigated materials, we have used three different ISO standard-like approaches. Results comparison for two different cases was conducted concluding that linear approximation of input fluencies range where optical damage probability is 0%<P <100% provides the lowest LIDT value for discussed examples, at the same time showing consistent and suitable for practical applications results.