DIN EN ISO 10938:2017-02

This International Standard applies to displays of optotypes generated by chart projectors and all other visual acuity measurement systems that use recognition of high-contrast optotypes and that are designed for general use, including optotypes printed on media (either opaque or intended for transillumination), those generated electronically, and those produced by optical projection. It is not applicable to special tests of visual acuity, such as statutory certificates of blindness, low vision or low contrast displays. The standard specifies certain characteristics of displays of optotypes used for measurement of visual acuity in general clinical practice. These characteristics include size specification, luminance, contrast, and resolution of the optotypes. It applies to displays intended for measurement of visual acuity over a limited, but clinically useful, range of acuities. This document has been prepared by ISO/TC 172 "Optics and photonics", Subcommittee 7 "Ophthalmic optics and instruments". Working Committee NA 027-01-08 AA "Augenoptik" ("Ophthalmic optics") at DIN Standards Committee Optics and Precision Mechanics (NAFuO) is responsible for the German participation.