Patent ID: 6698888
Filing Date: 2004-03-02
Classification: A61B

Abstract:
An ophthalmic refractor comprising:a housing; a viewing path through said housing; a lens carrier mounted in said housing, said lens carrier holding a plurality of lenses; a rotatable adjustment knob operatively connected to said lens carrier for enabling a user to selectively position a chosen lens in said viewing path; a ring-shaped scale including a first side having angularly spaced indicia for indicating an optical parameter related to said chosen lens and a second side opposite said first side, said scale having an internal gear; a scale drive gear fixed for rotation with said adjustment knob and meshing with said internal gear of said scale to rotate said scale upon rotation of said adjustment knob; and a bearing insert located internally with respect to said ring-shaped scale, said bearing insert acting to confine said ring-shaped scale in radial and axial directions.