Patents by Inventor Donald Lewis MacDonald

Donald Lewis MacDonald 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).

  • Publication number: 20040062388
    Abstract: An audio handset comprises a body (10) with an earphone (11) and a microphone (12). The microphone (12) has two ports on opposite faces (one of which, A, is seen in FIG. 1) and is mounted on the body (10) by hinge arms (14) to be displaceable, in use, between open and closed positions. In the open position, both ports are available to receive and respond to audible sound and the microphone functions in a noise-cancelling differential mode. In the closed position, one of the ports (A) bears against a sealing face (15) of the body rendering that port unresponsive to audible sound, and the microphone functions in a single port pressure mode.
    Type: Application
    Filed: October 28, 2003
    Publication date: April 1, 2004
    Inventors: Donald Lewis MacDonald, Peter Leighton Smith