In the ECB display (Electrically Controlled Birefringence), the undesirable color effects of STN technology are not compensated for, but used quite specifically. The different propagation speeds of the light cause different colors.
In the ECB display, the light is changed by electrically controlled birefringence in the liquid crystal cells. This requires two polarizers with which four to five colors can be displayed, depending on the voltage applied. In addition to black and white, these include red (R), green (G) and blue (B).
ECB displays are not suitable for color displays, however, but only for highlighting symbols or instructions.