BS EN 14139:2010 pdf free download

BS EN 14139:2010 pdf free download.Ophthalmic optics – Specifications for ready-to -wear spectacles.
BS EN 14139 specifies the minimum requirements for complete ready-to-wear spectacles. These are not intended for regular use without the approval of an eye-care professional.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
EN ISO 7998, Ophthalmic optics — Spectacle frames — Lists of equivalent terms and vocabulaiy (ISO 7998.2005)
EN ISO 8624, Ophthalmic optics — Spectacle frames — Measuring system and terminology (ISO 8624:2002)
EN ISO 8980-1. Ophthalmic optics — Uncut finished spectacle lenses — Part 1: Specifications for single-
vision and multifocal lenses (ISO 8980-1.2004)
EN ISO 12870, Ophthalmic optics — Spectacle frames — Requirements and test methods (ISO 12870:2004)
EN ISO 13666, Ophthalmic optics — Spectacle lenses— Vocabulary (ISO 13666:1998)
EN ISO 14889, Ophthalmic optics — Spectacle lenses — Fundamental requirements for uncut finished lenses
(ISO 14889:2003)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN ISO 7998 and in EN ISO 13666 and
the following apply.
ready-to-wear spectacles
spectades intended for near vision and reading use only having or incorporating a pair of single vision lenses of equal positive spherical power in which the glazing has not been carried out in direct response to a written prescription by a qualified practitioner
NOTE The term ready-to-wear spectacles as understood by this European Standard is restncted to spectacles having or incorporating single vision lenses, The rationale for this restriction is that spectade lenses other than single vision lenses (e.g. bifocal, multifocal, progressive-power lenses) are not recommended for use in ready-to-wear spectacles due to the need of a qualified practitioners prescription and dispensing for such lenses.
4 Performance requirements
4.1 General
The tolerances shall apply at a temperature of 23 °C土5。C.
4.2 General requirements
The spectacle lenses of ready-to-wear spectacles shall fulfil the general requirements of EN ISO 14889.
The frame of ready-to-wear spectacles shall fulfil the requirements of EN ISO 12870.
The glazing of spectacle lenses shall be verified by the lens retention test as specified in EN ISO 12870.
The spectacle lenses shall be securely held in position so that movement or rotation in the frame cannot occur
under any condition of intended use.
4.3 Optical power range
The lenses for ready-to-wear spectacles shall have equal nominal spherical power within the range from +1,00 to +3,50 dioptres.
4.4 Optical power tolerances
Tolerances to be applied to the values declared by the manufacturer shall comply with EN ISO 8980-1.
4.5 Reference points and prismatic power tolerances
4.5.1 Design reference points
— Horizontal: The design reference points are specified by the manufacturer and are spaced symmetrically with respect to the vertical symmetry axis of the frame according to EN ISO 8624.
— Vertical: The design reference points may be specified by the manufacturer and shall be at the same height for each lens.
4.5.2 Prismatic power tolerances
The deviation of prismatic power (horizontal: per lens; vertical: difference between lenses) measured at the design reference points specified by the manufacturer, shall not exceed the values given in Table 1.BS EN 14139 pdf download.