Patents Assigned to Better Environmental Development Corporation
  • Optical filters
    Patent number: 4106857
    Abstract: Rare earth elements with partially filled 4f electron shells are used to form a class of absorption type band pass optical filters. The rare earth elements are advantageously incorporated in glass at concentrations with the rare earth atoms constituting upwards of 15% of all the metallic atoms. Filters with pass bands less than 5% of the center wavelength are realized.
    Type: Grant
    Filed: August 9, 1976
    Date of Patent: August 15, 1978
    Assignee: Better Environmental Development Corporation
    Inventor: Elias Snitzer