To accurately make judgement as to whether or not a spectacle lens subjected to a thermal change is suitable for the round form of a spectacle frame by providing a lens shape correction means for correcting shape data on the basis of results detected with a shape change amount detection means.
A measurement arm is moved up and down and, then, a temperature detection index passes a gap between the opposed walls of a detection sensor 102. The index is thereby detected with the detection sensor 102. In this case, the detection sensor 102 detects the size of the index over an area from one end to the other end, and inputs the size to an operation control circuit 8. This circuit 8 finds a radius vector and a travel distance for every rotation angle, depending on a temperature variation. Values so obtained are stored in a memory M2 as lens shape information.
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