A 2 dioptre magnifier for welding helmets. A dioptre is a standard unit of measurement used to express the optical power of a lense in mathematical terms. A dioptre is the reciprocal value of the focal length measured in metre. This magnifying lens has a focal length of 50 cm therefore the dioptre is ( 1 divided by 0.5metres ) = 2. What this means is that objects which are 50cm from the lens are in focus and magnified.
This magnifier should fit most helmets on the market and can be trimmed down with a file to suit your needs or taped into position.
Dimensions are 107mm x 51mm x 3.9mm