Patent ID: 6666555
Filing Date: 2003-12-23
Classification: A61B

Abstract:
In an ophthalmic refractor of the type having a cylinder power knob for selectively positioning at least one cylinder lens of chosen power in a patient viewing path of said ophthalmic refractor; a cylinder power readout corresponding to said cylinder power knob for displaying the resultant power of said at least one cylinder lens to an operator; a polar cylinder axis scale; and a cylinder axis knob coaxial with and rotatable relative to said cylinder axis scale for adjusting the cylinder axis of said at least one cylinder lens, said cylinder axis knob including a cylinder axis pointer cooperating with said cylinder axis scale for indicating said cylinder axis to an operator; the improvement comprising:said cylinder axis scale being formed as a light-transmitting component having opaque scale gradations; a polar array of light-emitting diodes mounted on a single circuit board and arranged to project light through said cylinder axis scale; and means for connecting a power source to said circuit board, said power source being external to said ophthalmic refractor.