Abstract: Optical information is stored in a member which includes a layer of electrochromic material and an electrolyte in contact with the electrochromic material. The electrolyte has particles of photoconductive material therein. The member is exposed to optical information such that electron-hole pairs are formed in the photoconductive material. The creation of the electron-hole pairs produces persistent coloration in the electrochromic material in an area which corresponds to the optical information. If desired, the stored information can be erased by applying an electric field to the member.

Abstract: An electrochromic device includes a layer of electrochromic material, such as tungsten oxide. The electrochromic material includes a dopant, such as molybdenum oxide. A sufficient amount of the dopant, for example, 2% by atomic weight, functions to shift the natural color center absorption peak of the electrochromic layer. Due to the shift of the color center absorption peak, coloration of the layer of electrochromic material exhibits an improved match to the spectral sensitivity of the human eye. Consequently, less electrical energy is required to operate the device at satisfactory viewing levels as compared to conventional devices where the color center absorption peak is less closely matched to the spectral sensitivity of the human eye.

Abstract: A layer of electrochromic material is on a substrate. An acid electrolyte is on the layer of electrochromic material. An indium electrode is utilized to produce coloration in the layer of electrochromic material without the need for any external electrical power. If a conductor layer is disposed between the substrate and the layer of electrochromic material, the device operates under a biasing voltage with substantially no polarization.