EP3663840A1 - LINE OF SIGHT DETECTION DEVICE, DISPLAY METHOD, LINE OF SIGHT DETECTION DEVICE CALIBRATION METHOD, SPECTACLE LENS DESIGN METHOD, SPECTACLE LENS SELECTION METHOD, SPECTACLE LENS MANUFACTURING METHOD, PRINTED MATTER, SPECTACLE LENS SALES METHOD, OPTICAL DEVICE, LINE OF SIGHT INFORMATION DETECTION METHOD, OPTICAL INSTRUMENT DESIGN METHOD, OPTICAL INSTRUMENT, OPTICAL INSTRUMENT SELECTION METHOD, AND OPTICAL INSTRUMENT PRODUCTION METHOD | Patent Bear