To enable improvement in a rate of fitting in a spectacle frame of a spectacle lens after V-block processing even if thinning, distortion, etc. can be caused to a V-block shape by interference of a processing tool, and realize supply of the V-block-processed spectacle lens with stable quality.
A perimeter calculation device comprises: predicted shape identification means 201b for obtaining a predicted finished V-block shape considering an interference amount of processing tool when applying V-block processing to an unprocessed spectacle lens; and theoretical peripheral length calculation means 201d for obtaining a V-block perimeter in a spectacle lens having the predicted finished shape obtained by the predicted shape identification means 201b, as a theoretical perimeter of the spectacle lens.
| JPH05111866A | 1993-05-07 | |||
| JPH11285957A | 1999-10-19 | |||
| JPH06175087A | 1994-06-24 |
Toru Yui
Hitoshi Kiyono
Fukuoka Masahiro
Okuyama Tomohiro