Electrochromic display device

摘要

In an electrochromic display device including a pair of opposed substrates, a display electrode formed on one of the substrates and a counter electrode formed on the other substrate, the response speed and display life of the device are improved by its novel counter electrode structure including a low conductive film arranged to face the display electrode and a high conductive film arranged to uncover, adjoin or cover the former. Alternatively, the low conductive film is embedded in the high conductive film to face the display electrode. Each of the conductive films is essentially made of In2O3, In2O3-SnO2 or SnO2. The high conductive film may be made of Au, Ag or Pt. Where the low conductive film is an insulating film, it is sandwiched by the high conductive films. The insulating film is made of a metal oxide, metal fluoride or metal nitride. The difference in electric resistance between the low and high conductive films is selected 10 times or more. This novel counter electrode structure reduces the leakage current and provides a uniform current density distribution thus ensuring an improved response speed and display life.