The improvement has come through advances in the transistor matrix backplane. The new displays use the same Eink overlay as the company’s previous displays. Further image improvements can be expected when using the latest e-paper technology. Prior to the new technology, Plastic Logic’s most advanced commercially available display was 196ppi in a 4.7” form factor.
The 500ppi displays make written text much sharper. This is particularly positive for symbol-based languages such as Chinese and Japanese where detail has previously been lost due to PPI limitations. Another use case benefiting from the improved display density would be applications where accurate lines/measurements are critical, such as ePaper rulers, portable mapping or CAD drawings.