基于PJND的平视显示器可读性评价方法

Readability Evaluation of Head-Up Display Based on PJND

为了研究环境亮度、背景色度变化以及干扰(镜面反射、漫反射和眩光)对平视显示器可读性的影响,通过对最小可辨差异(PJND)理论的研究,结合平视显示器及应用环境特点,建立了基于PJND的平视显示器可读性评价模型。仿真及实验结果表明:可用PJND值来评价平视显示器的可读性;为满足可读性,随着环境亮度变大,亮度对比度应该逐渐减小,低亮度环境下对亮度对比度的要求大于高亮度环境;背景色度与目标色度差异越大,可读性对亮度对比度的要求越低;环境亮度不变、干扰值变大时,可通过增大亮度对比度来满足可读性,干扰值超过一定范围,可通过物理遮挡来满足可读性。

To study the impacts of environment luminance, chromaticity of background and interferences （ including specular reflection, diffuse reflection and glare） on the readability of Head-Up Display （HUD）, a readability evaluation model was established based on Perceptible Just Noticeable Difference （PJND） theory by taking the characteristics of HUD and its environment into consideration. Simulations and experiments result shows that： 1 ） The value of PJND can be used for evaluating the readability of HUD; 2） Low-luminance environment has a higher luminance contrast requirement than high-luminance environment;To satisfy the readability, the HUD needs to lower the luminance contrast when the ambient luminance increases; 3 ） The bigger the difference between background chromaticity and object chromaticity, the lower the requirement to luminance contrast; and 4 ） When the environment luminance is constant and the interferences increase, a higher luminance contrast can be used to satisfy the readability; when the interference luminance is beyond the maximum, physical occlusion is a way to satisfy the readability.