Scope: This part of IEC 62595 focuses on common issues of light emission such as spatial uniformity of luminance and colour, and angular distribution of luminance and colour, from lighting units with arbitrary shapes like flexible lighting sources (FLSs). This document provides a model of light emission from a curved FLS and of light measurement on a curved FLS. Because the development of flexible liquid crystal panels is in progress (see the notes), the intent of this document is to provide guidance for the development of future measurement standards. This document is applicable to FLSs either as light sources, products or elements with arbitrary shapes of geometrical curvature having different spectral and spatial characteristics of lightemission.NOTE 1 Almost 20 years ago plastic LCDs were developed and used in a few applications.NOTE 2 Flexible BLUs have been used for bendable LC panels in recent years.NOTE 3 Recent transmissive and transflective flexible LCs require flexible BLUs.