Modeling of LCD Reflection Characteristics and Simulation Method of LC-displayed Images Under Daylight Conditions

Abstract

It is known, that daylight reflection on an LCD significantly degrades the visual quality and readability of a display. Methods to mitigate this problem like daylight image enhancement are mainly based on the assumption that the reflection is linearly dependent of the daylight intensity. It was found out by extensive measurements that the reflection also depends on the gray-value of a pixel and thus image contents [1]. The reflection at a white image may exceed two-times of that at a dark image. In this paper, the reflection is modelled as a function of the transmission value of a (sub)pixel and is decomposed into three parts, namely a constant part for the surface reflection, a linear term for the LC-cell and a square term for the reflection of the BLU. This refined and, regarding the daylight direction, generalized model leads to an excellent agreement with measurements.