Regarding marking/blocking polarized lenses,
my present conception is as follows:
1. On a spherical lens, you may safely rotate the lens so that the lensometer dot line coincides with a line connecting the two edge marks on the polarized lens.
2. On a lens with cylinder correction, the alignment of the cylinder axis is done in the usual way. If, when the lens is oriented properly for spotting, the polarization-axis line is not coincident with the spot-line, the lens was manufactured wrongly and is unusable.
Is this correct?
What is the difference between the "180 line" and the axis of polarization?
Kurt
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