03/117773 DC : DRAFT DEC 2003
Superseded
A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.
A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.
BS EN ISO 9342-2 - OPHTHALMIC OPTICS AND INSTRUMENTS - TEST LENSES FOR CALIBRATION OF FOCIMETERS - PART 2: TEST LENSES FOR FOCIMETERS USED FOR MEASURING CONTACT LENSES
19-01-2006
23-11-2012
Foreword
1 Scope
2 Normative references
3 Definitions
4 Design requirements and recommendations for test lenses
4.1 General
4.2 Spherical test lens
5 Tolerances for spherical test lenses
Annex A (informative) Manufacture of test lenses for
calibration of focimeters used for
measuring contact lenses
A.1 General
A.2 Selection of glass
A.3 The nominal back surface radius of curvature
A.4 Selection of the back surface radius
A.5 Calculation of lens thickness and selection of front
surface radius
A.6 Calculation of back vertex power
A.7 Production tolerances
A.8 Expanded uncertainty
A.8.1 General
A.8.2 Components of uncertainty
A.8.3 Combined standard uncertainty
A.8.4 Expanded uncertainty
A.9 Example for a test lens +10,0 m[-1]
A.9.1 Calculation of production data
A.9.2 Consideration of uncertainty summation
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