1 This International Standard specifies the characteristics of the following types of low-power magnifiers and gives recommendations for their selection for the inspection of surfaces.
— Single-element magnifiers of magnification typically up to ×4 (Type A).
— Multi-element magnifiers of magnification typically up to ×10 (Type B).
— Twin-system magnifiers of magnification typically up to ×15 (Type C), categorized as follows:
a) binocular, normally with a long working distance (Type C.1);
b) bi-ocular, including those refined with stops or other attachments, for quasi-stereoscopic vision (Type C.2).
— Concave-mirror magnifiers with front-surface reflectors in powers typically up to ×6 (Type D).
2 This International Standard is not concerned with:
— watch-makers' loupes and spectacles;
— single-element, spherical- or cylindrical-lens magnifiers in which either the lens or the lens-mount rests on the surface of the object to be examined (this includes magnifiers provided with any form of graduated scale for the purpose of measurement);
— plastic lens sacs, liquid-filled;
— magnifiers intended for the examination of internal surfaces.
BS ISO 3058:1998 history
0000 BS ISO 3058:1998(1999)
1998BS ISO 3058:1998 Non-destructive testing - Aids to visual inspection - Selection of low-power magnifiers