This technical report intends to visualize common issues of light emission from lighting units with arbitrary shapes like flexible lighting sources (FLSs), such as spatial uniformity of luminance and colour, and angular-distribution of luminance and colour. This TR provides a model of light emission from curved FLS, and of light measurement on curved FLS. The intent of this TR is to provide guidance for the development of future measurement standards, since development of flexible liquid crystal panels are in progress (refer to notes). This document is applicable to FLSs either light sources, products or elements with arbitrary shapes of geometrical curvature having different spectral and spatial characteristics of light emission.