Ophthalmic optics. Visual acuity testing. Standard and clinical optotypes and their presentation Ingestion-build-134498 BS EN 4803 guidelines enable

BS EN 4803 guidelines enable you to design

which enables a guarantee of accuracy corresponding to the special features

BS EN 13636 specifies the principles for the implementation of a system of cathodic protection against corrosive attacks on buried metal tanks and associated piping

BS EN 60695-1-30 is a part of an international standard that covers safety guidelines for fire hazard testing

Ophthalmic optics. Visual acuity testing. Standard and clinical optotypes and their presentation Ingestion-build-134498 BS EN 4803 guidelines enable1 Scope This document specifies a range of Landolt ring optotypes and describes a method for measuring distance visual acuity under photopic conditions for the purposes of certification or licensing. This document is neither intended as a standard for clinical measurements nor for the certification of blindness or partial sight. Other optotypes used for clinical investigations are described in Annex A for information.