Optical photopolymers for additive manufacturing: reporting practices and cross-study comparability

The optical performance of photopolymers used in additive manufacturing is characterised through multiple parameters, including refractive index and dispersion, transmittance and absorption, surface quality, birefringence and scattering. Reported values are obtained from samples that have passed through specific fabrication and post-processing workflows and are measured under configurations that document wavelength, geometry, sample state and method with varying degrees of completeness. This focused review examines reporting practices in a bounded corpus of optical-additive-manufacturing studies. Three observations emerge. First, the surveyed corpus shows recurrent partial completeness rather than a uniform reporting deficit: different studies emphasise different subsets of the optical parameter space according to their methodological objective. Second, some studies provide either explicit qualification of what a reported quantity does and does not characterise or reusable parameters that permit downstream reconstruction by an independent reader. Third, standards and reference conventions relevant to refractive index, transmittance, haze, colour and additive-manufacturing terminology are available, but they are not used uniformly across the surveyed studies. Within the limits of this focused corpus, cross-study comparability therefore depends strongly on the measurement context co-reported with each optical value.