ISO 11984 pdf download

ISO 11984 pdf download.Ophthalmic optics — Contact lenses — Determination of rigid lens flexure and breakage 1 Scope This International Standard describes a method for determining the flexural properties of finished rigid contact lenses when tested under specified conditions. The existence of this International Standard does not imply in any way that the testing of contact lenses for flexure and breakage is a requirement. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 8320:1 986, Optics and optical instruments — Contact lenses — Vocabulary and symbols. ISO 9337-1 , Contact lenses — Determination of back vertex power — Part 1 : Method using focimeter with manual focusing. ISO 9337-2, Contact lenses — Determination of back vertex power — Part 2: Measurement on contact lenses immersed in saline. ISO 9338:1 996, Optics and optical instruments — Contact lenses — Determination of diameters. ISO 9339-1 , Optics and optical instruments — Contact lenses — Determination of thickness — Part 1 : Rigid contact lenses. ISO 1 0338:1 996, Optics and optical instruments — Contact lenses — Determination of curvature. ISO 1 0344:1 996, Optics and optical instruments — Contact lenses — Saline solution for contact lens testing. 3 Terms and definitions For the purposes of this International Standard, the terms and definitions given in ISO 8320 apply, together with the following. 3.1 flexural deformation reduction of the diameter of the contact lens due to a load applied to the edge of the contact lens, perpendicular to the lens axis, to induce flexure NOTE It is expressed as a percentage of the original lens diameter.3.3 flexural deformation strength load applied at the contact lens edge at a specific point during a flexural loading test NOTE For the purposes of this International Standard, the flexural deformation strength at rupture and at a 30 % deformation of the contact lens are of primary importance. 3.4 conditioning procedure intended to bring a sample or test...