An improved electrochromic device, the device incorporating an electrochromic medium that comprises at least three electroactive materials having absorption spectra that add together such that the color of the electrochromic medium can be pre-selected by individually choosing the concentrations of the...http://www.google.com.au/patents/US6020987?utm_source=gb-gplus-sharePatent US6020987 - Electrochromic medium capable of producing a pre-selected color
