US 6,981,946 B2
Load sensing applanation tonometer
Jeffery C. Davidson, Hamersville, Ohio (US)
Assigned to J.D. Mueller Company, LLC, Cincinnati, Ohio (US)
Filed on Apr. 17, 2003, as Appl. No. 10/417,825.
Prior Publication US 2004/0210123 A1, Oct. 21, 2004
Int. Cl. A61B 3/16 (2006.01)
U.S. Cl. 600—405 15 Claims
OG exemplary drawing
 
1. An applanation tonometer for measuring the intraocular pressure of an eye using a microscope, comprising:
a housing configured to be mounted proximate the microscope;
a support arm having first and second ends, said first end movably coupled to said housing;
an applanation probe coupled to said second end of said support arm for movement into contact with the cornea of the eye, said probe having a contact surface for applanating the cornea of the eye and a prism assembly cooperating with said contact surface such that the applanated cornea may be viewed through the microscope;
a force sensor disposed within said housing and engageable with said support arm, whereby force applied to said probe by contact with the applanated cornea is sensed by said sensor through said support arm;
a display in communication with said sensor and configured to indicate a value corresponding to the force sensed by said force sensor;
a rotatable knob operatively coupled to said support arm, whereby rotation of the knob causes said support arm to move and thereby move said probe toward or away from the cornea of the eye;
a slidable base disposed within said housing; and
a cam coupled between said rotatable knob and said support arm, said cam mounted to said slidable base and configured to convert rotational movement of said knob into translational movement of said base.