Patent ID: 7527377

Claim:
A method of manually centering, in a rim of a spectacles frame, an ophthalmic lens that is provided with at least one center and/or axis marking, the method comprising the steps of: a) for calibration purposes, acquiring and storing a shadow of an opaque sign formed on a transparent sign support interposed between lighting means and acquisition means while said support is being illuminated on its own by said lighting means; b) superposing said ophthalmic lens and said transparent sign support; c) acquiring and storing the shadow of said opaque sign of said support as deflected by said ophthalmic lens while said ophthalmic lens and said support are being illuminated together by said lighting means; d) using the acquisition means to acquire a shadow of the center and/or axis marking of the ophthalmic lens for centering while it is illuminated by said lighting means and superposed on said transparent sign support; e) displaying on a display screen visible to an operator firstly the shadow of the center and/or axis marking of the ophthalmic lens, and secondly a virtual centering target corresponding to a position desired for the center marking of the lens relative to a reference point of the rim of the frame; f) from the prismatic deflection of the opaque sign as measured by comparing the acquisitions of steps a) and c), deducing a corrected relative position for the reference point of the frame rim relative to the center marking, or vice versa; and g) putting the shadow of the centering marking of the ophthalmic lens into coincidence with the centering virtual target.