Method for measurement of the refractive index of spectacle lenses, whereby a prism is used in conjunction with a measurement instrument so that measurements on varying refractive index lenses can be made

摘要

Method for measuring the refractive index in near and far reference points for multiple strength spectacle lenses, especially for lenses with a varying refractive index using an automatic peak refractive index measurement instrument (1). Accordingly a prism (2) is placed in the beam path of the measurement instrument. The prism serves at least to partially compensate spectacle lenses in the measured region. The base of the prism can be rotated through 180o in the axis of the beam path for measurement of the far and near reference points.