Ophthalmic optics – Mounted spectacle lenses (ISO 21987:2009)
Abstract
ISO 21987:2009 specifies requirements for mounted spectacle lenses relative to the prescription order.
DIN EN ISO 21987:2010-02 (E)
Ophthalmic optics – Mounted spectacle lenses (ISO 21987:2009)
Contents Page
Foreword ……………………………………………………………………………………………………………………………………….3
1 Scope ……………………………………………………………………………………………………………………………..4
2 Normative references ……………………………………………………………………………………………………..4
3 Terms and definitions ……………………………………………………………………………………………………..4
4 Classification ………………………………………………………………………………………………………………….5
5 Requirements …………………………………………………………………………………………………………………5
5.1 Reference temperature ……………………………………………………………………………………………………5
5.2 Lenses used in manufacturing complete spectacles ………………………………………………………..5
5.3 Optical requirements ………………………………………………………………………………………………………5
5.4 Thickness tolerance ………………………………………………………………………………………………………..9
5.5 Positioning tolerances …………………………………………………………………………………………………….9
6 Test methods ………………………………………………………………………………………………………………..10
6.1 General …………………………………………………………………………………………………………………………10
6.2 Measurement method for the back vertex power of single-vision lenses and the distance
portion of multifocal and progressive-power lenses and near portion of degressivepower
lenses …………………………………………………………………………………………………………………11
6.3 Measurement method for cylinder axis ………………………………………………………………………….11
6.4 Addition power measurement ………………………………………………………………………………………..11
6.5 6.6 Material and surface quality ……………………………………………………………………………………..13
6.7 Prism imbalance (relative prism error) measurement method for pairs of single-vision
and multifocal lenses …………………………………………………………………………………………………….13
7 Marking for progressive-power and degressive-power lenses ………………………………………..13
7.1 Permanent marking ……………………………………………………………………………………………………….13
7.2 8 Identification ………………………………………………………………………………………………………………14
9 Reference to ISO 21987 …………………………………………………………………………………………………14
Annex A (informative) Material and surface quality ……………………………………………………………………….15
Annex B (informative) Recommendations on mounting …………………………………………………………………16
Annex C (informative) Alternative methods for measuring prism imbalance (relative prism error)
for pairs of single-vision and multifocal lenses ………………………………………………………………18
Bibliography …………………………………………………………………………………………………………………………………20
Requirements of EU Directive 93/42/EEC ………………………………………………………………………………………21
Annex ZA (informative) Relationship between this European Standard and the Essential Nonpermanent
marking ……………………………………………………………………………………………………….14
Method for measuring position and tilt ………………………………………………………………………………………….13