Patents Assigned to Oy Master Instruments Ltd.
  • Mask compass
    Patent number: 4953304
    Abstract: The invention relates to a mask compass comprising a case attached to the outer surface of glass of goggles. The compass box is placed inside the casing. Thus the checking of the compass does not interfere with regular diving movements and e.g. cause deviations from the right direction.
    Type: Grant
    Filed: April 27, 1989
    Date of Patent: September 4, 1990
    Assignee: Oy Master Instruments Ltd.
    Inventors: Raimo Raitmaa, Per-Olof Jansson