PD ISO/TR 28980:2007
Current
The latest, up-to-date edition.
Ophthalmic optics. Spectacle lenses. Parameters affecting lens power measurement
Hardcopy , PDF
English
28-09-2007
Foreword
1 Scope
2 Discrepancies due to different focimeter designs and
measurement methods
2.1 Focimeter design
2.2 Wavelength dependence
2.3 Target pattern
2.4 Front vertex versus back vertex measurements
2.5 Choice of the focus
3 Systematic errors
3.1 Non-linear errors
3.2 Lens sag error
3.3 Temperature dependence
3.4 Calibration
3.5 Accuracy versus display step
4 Random errors
4.1 General
4.2 Focusing issues: Theoretical limit
4.3 Positioning issues
5 Conclusion
Bibliography
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