[New DIN norms for determination of visual acuity].

In 2009 the DIN 58220 norms for determination of visual acuity were revised. The new rules came into force on 1(st) November 2009. The new regulations on expert assessment of visual acuity (DIN norm 58220, part 3) are particularly important for ophthalmologists because as a result of the revisions the approach to testing visual acuity in patients with low acuity must be changed in the future. The background and potential problems will be presented and a simple solution for the lower acuity range will be suggested. Parts 5 (general test of vision) and 6 (driving-related vision test) of DIN 58220 remain practically unchanged. Part 7 of DIN 58220 is newly introduced, in which regulations for testing mesopic contrast vision with and without glare are defined for the first time.