Abstract:
The invention relates to a method for measuring the refractive index (n) of an ophthalmic lens (1) defined by a first side (3) and a second side (5), said method comprising the following steps: the co-ordinates of at least one group of three surrounding points (A1, A2, A3) located on the first side (3) of the lens (1) at close proximity to an incidence point (A) and distributed around the same are determined; the co-ordinates of at least one group of three surrounding points (B1, B2, B3) located on the second side (5) of the lens (1) at close proximity to an emergence point (B) and distributed around the same are determined; and the refractive index (n) of the lens (1) is calculated from the co-ordinates of said surrounding points (A1, A2, A3, B1, B2, B3) and the deviation of an incident light beam in A and an emergent light beam in B.