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Donald L. Johanson

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  • Wayland, MA, US
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Patents Grantslast 30 patents

  • Information Patent Grant

    Hearing aid
    • Patent number D266271
    • Issue date Sep 21, 1982
    • Audivox, Inc.
    • Donald L. Johanson
    • D24 - Medical and laboratory equipment
  • Information Patent Grant

    Modular in-the-ear hearing aid
    • Patent number 4,069,400
    • Issue date Jan 17, 1978
    • United States Surgical Corporation
    • Donald L. Johanson
    • H04 - ELECTRIC COMMUNICATION TECHNIQUE
  • Information Patent Grant

    Directional/non-directional hearing aid
    • Patent number 3,975,599
    • Issue date Aug 17, 1976
    • United States Surgical Corporation
    • Donald L. Johanson
    • H04 - ELECTRIC COMMUNICATION TECHNIQUE