Pairs of data (room lights off→room lights on) for EDTRS charts.

For luminance and contrast, values represent the mean of the nine values measured across the chart for black letters and for adjacent white areas. Chart parameters which do not meet the BS 4274 requirements are in bold.

关于亮度与对比度，其数值为图表中黑色文字区域及相邻白色区域的九项测量结果的平均值。不符合BS 4274标准要求的图表参数以粗体标注。