Patents by Inventor Charles L. Spann

Charles L. Spann 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).

  • Electro-magnetic interference shield for a telephone handset
    Patent number: 5819162
    Abstract: An electromagnetic interference (EMI) shield for a handheld cellular phone that is particularly useful for shielding a hearing aid against EMI from the phone's antenna. The device includes a base and a flap laminated with a metallic shielding. The base attaches to the receiver end of the cellular phone and the flap rests over the base when the phone is not in use. In operation, the flap extends away from the base forming an enclosure about the user's ear for shielding the hearing aid from EMI when the phone is in use.
    Type: Grant
    Filed: July 31, 1996
    Date of Patent: October 6, 1998
    Assignee: Northern Telecom Limited
    Inventors: Charles L. Spann, Michael J. Lynch