Patents by Inventor Dean A. Ersfeld

Dean A. Ersfeld has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Reusable radiation monitor
    Patent number: 4130760
    Abstract: An integrating, reusable device for monitoring exposure to actinic radiation is disclosed. The device comprises a substrate having deposited thereon at least one photochromic aziridine compound which is sealed in an oxygen barrier to stabilize the color developed by the aziridine compound in response to actinic radiation. The device includes a spectral response shaping filter to transmit only actinic radiation of the type being monitored. A color standard is also provided with which to compare the color developed by the aziridine compound.
    Type: Grant
    Filed: June 29, 1977
    Date of Patent: December 19, 1978
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Dan L. Fanselow, Dean A. Ersfeld