English to Italian Law/Patents Medical: Instruments

Norma UNI EN ISO 21987
Opthalmic optics -Mounted spectacle lenses

Verification method for planes of transmission of polarizing lenses

For the determination of the plane of transmission, a polarizer of known plane of transmission in the light path shall be used.

Apparatus

A pair of polarizers is cut to give planes of transmission at a +3° and a –3° angle from the horizontal.
The top and bottom halves of the polarizers shall be then joined together and glass mounted, with the line of the joint horizontal to form a split-field polarizer.
The split-field polarizer shall be capable of being rotated by means of a lever carrying a corresponding pointer.
The pointer transverses a scale calibrated in degrees left or right of zero.
The split fields shall be illuminated from behind by a diffused light source.

"le metà.... dei polarizzatori devono essere unite e montate su occhiali??..."