MEASUREMENT OF BACK RADIUS OF CURVATURE AND CENTER MATERIAL THICKNESS OF A CONTACT LENS IN SOLUTION
Application IN/PCT/2001/00951 published 2006-04-07, filed 2001-09-13
The application relates to a method and device for simultaneously measuring the center material thickness and back radius of curvature of a lens, and in particular a toric disposable ophthalmic lens. An ultrasound wave is radiated by a transducer towards a lens and reflected off the front and back surfaces of the lens. Based on the lapse in time between respective echoes the center material thickness and the sagittal height of the lens is determined. The back radius of curvature is calculated from known geometric relationships between the chord of a circle and the sagittal height (FIG. - 1)
Applicant
JOHNSON & JOHNSON VISION CARE INC
7500 CENTURION PARKWAY SUITE 100, JACKSONVILLE FLORIDA 32256 USA
Inventor
ROSS DENWOOD EBEL JAMES A LEWIS YULIN LONGO JEFFREY RICE BRIAN
International Info
Classification: G01B 17/02,G01M 11/02
Publication Number: WO 01/51888 A1
Application Date: 2001-01-11
Priority Information
09/483,363 US 2000-01-14