Patent ID: 9005125
Filing Date: 2015-04-14
Classification: A61B

Abstract:
1. A tonometer for measuring the intraocular pressure of an eye with the eyelid closed, said tonometer including a pair of arms, said arms pivotally connected at proximal ends thereof, and each arm having a distal end, said arms being manually moveable between an open position where the distal ends are separated to enable said distal ends to be manually positioned against the closed eyelid and a measuring position where the arms are manually moved towards each other while in contact with the closed eyelid so the distal ends are at a predetermined distance from each other to apply the same external pressure against the eye with each measurement of intraocular pressure, a resilient pad attached to a distal end of one arm, said pad positioned to make physical contact with a closed eyelid of the eye being tested and be deformed when the arms are moved to the measuring position, a solid state pressure transducer disposed within the one arm, said transducer being a piezoelectric crystal in intimate physical contact with the resilient pad, said transducer configured to provide an electrical signal in proportion to the deflection of the pad that corresponds to the intraocular pressure of the eye being tested in response to the resilient pad being pressed against the closed eyelid of said eye being tested, and a control circuit including a micro-processor, said transducer and a display to indicate the intraocular pressure of the eye.