×

Electrochromic architectural window

  • US 5,725,809 A
  • Filed: 10/17/1996
  • Issued: 03/10/1998
  • Est. Priority Date: 11/29/1989
  • Status: Expired due to Fees
First Claim
Patent Images

1. A variable transmission electrochromic architectural window comprising:

  • first and second spaced optically transparent elements, said elements each having front and rear surfaces and defining a space between the rear surface of said first element and the front surface of said second element;

    an electrochromic medium confined in said space whose light transmission is variable upon the application of an electric field thereto;

    means for applying an electric field to said electrochromic medium to cause variation in the light transmittance of said medium wherein said means for applying an electric field includes a substantially transparent conductive coating on at least one of said rear surface of said first element and said front surface of said second element;

    said electrochromic medium including a solvent and a redox chemical pair in solution in said solvent wherein said redox chemical pair colors under the application of voltage and bleaches in the absence of an applied voltage;

    an ultraviolet stabilizer in solution in said solvent whereby said redox chemical pair dissolved in said solvent is provided with enhanced ultraviolet stability;

    said electrochromic architectural window having an electrochromically active large area of length dimension at least about 14 cm and of width dimension at least about 14 cm;

    said electrochromic architectural window exhibiting a steady state leakage current of less than about 2.68 amperes per square meter when a potential of one volt is applied to said electrochromic architectural window whereby coloration uniformity of said electrochromic architectural window is enhanced.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×