New at N & H are customized Electronic Paper Displays . The displays, mainly used in e-book readers, are extremely energy efficient , flexible, robust and full of contrasts .
How does an EPD work ?
Electrophoresis refers to the movement of electrically charged particles by an electric field . EPDs are in this electric field by microcapsules. They contain a positive charge white particles and negative charge black particles. The microcapsules are in a liquid between a transparent front electrode and a reflective back electrode . This back electrode is an active matrix through which the electric fields are generated for the microspheres. Through this no backlighting is required , because it reflected > 40 % of the ambient light .
Why are EPDs so energy saving ?
As a bi-stable displays EPDs may have two stable states – light or dark. The states are maintained without power supply. EPDs retain their charge image without further supply of energy and consequently need only power when the display change. An LCD display needs a constant power supply . In a direct comparison of a 12 ” EPDs and a 12 ” LCD operation, the EPD requires for a 20 hours time a power supply of a AA battery, a LCD 36 AA batteries . Even solar operation is possible with e-paper displays .
More detailed technical specifications
The e-paper displays have, depending on the variant, a thickness of < 1 mm and up to 16 grayscale display . They provide a natural black and white with a contrast ratio of at least 7:1. The viewing angle is nearly 180 ° , the resolution more than 100 ppi . Motion effects can be realized by an electronic control unit . All custom shapes and sizes can be produced .