[Comparative research at the "mesoptometer" and "nyktomat" (author's transl)].

This paper deals with the results of comparative reserach into twilight vision as found by tests at the "Mesoptometer" and "Nyktomat". The research population consisted of 168 persons. Their reactions at the test instruments during various functional tests are demonstrated by means of diagrams. While there is good correspondence between the two test instruments in the range of contrast essential for attesting night driving ability, differences can be shown to exist in the critical range of marginal values.