Method for manually centering an ophthalmic lens in a centering/locking device and associted centering/locking device

A method of manually centering, in a rim (200) of a spectacles frame, an ophthalmic lens (103) that is provided with at least one center and/or axis marking (PC), the method comprising the steps consisting in:

• a) for calibration purposes, acquiring and storing the shadow of an opaque sign (124A;
• 124B) formed on a transparent sign support (124) interposed between lighting means (S) and acquisition means (C) 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 detected by said ophthalmic lens while said ophthalmic lens and said support are being illuminated together by said lighting means;
• d) using the acquisition means (C) to acquire the shadow of the center and/or axis marking (PC) of the ophthalmic lens (103) for centering while it is illuminated by said lighting means;
• e) displaying on a display screen (105) firstly the shadow of the center and/or axis marking (PC) of the ophthalmic lens (103), and secondly a virtual centering target (CC) corresponding to the position desired for the center marking (PC) of the lens (103) relative to a reference point (CB) of the rim (200) of the frame;
• f) from the prismatic deflection of the opaque sign (124A;
• 124B) as measured by comparing the acquisitions of steps a) and c), deducing a corrected relative position (CBc) for the reference point (CB) of the frame rim (200) relative to the center marking (PC), or vice versa;
• and
• g) putting the shadow of the centering marking (PC) of the ophthalmic lens (103) into coincidence with the centering virtual target (CC).