Optics and optical instruments. Reference wavelengths1 Scope This International Standard specifies two reference wavelengths to be used for the characterization of optical materials, optical systems and instruments, as well as ophthalmic lenses. It defines the associated principal refractive indices and principal dispersions, as well as the Abbe numbers with regard to these reference wavelengths and principal dispersions.

Owing to its high potential accuracy

Contents of BS ISO 12647:

but which are relevant to the UK’s climate and construction practices

Due to the additional force on the spring

Requirements are given for tolerances on dimensions

and housings

which are tested under application of EN 50342-1:2015

The appointed “responsible person” needs to have:

Conformance tables

and manufacturing processes when specified by the user

This standard revises and replaces BS EN 62402:2007 Obsolescence Management - Application guide

solar thermal energy