Effects of Environmental Illuminance on the Readability of E-Books

We carried out experiments to evaluate the readability of e-books using different display systems. We used two types of e-paper (Amazon KindleDX and 300dpiEPD), one type of backlit LCD (new iPad), and ordinary paper text. In the experiments, we conducted subjective evaluations and measured viewing distance. This study found a dependency between readability and illuminance of each device.