title: [Stages in the development of instruments for determining subjective refraction].
abstract: By the equipments constructed from the J. D. Möller Company in Wedel during the last 40 years the different stages of development of the phoropter are shown. There was a big step from the simple technology of the VISUTEST-A to the VISUTEST-C-Phoropter, which in connection with the inclination apparatus according to Reiner is one of the most successful equipments of German output. VISUTRON, which is the first motor-operated phoropter, started a new era. Concerning VISUTRON-Plus, the latest product of this series, great importance was especially set to efficient and easy operation.
authors.affiliation: Abteilung für Entwicklung, Firma J.D. Möller, Wedel.
authors.forename: L
authors.initials: L
authors.lastname: Twisselmann
authors.forename: J
authors.initials: J
authors.lastname: Forchmann
authors.forename: W
authors.initials: W
authors.lastname: Duis
mesh_terms: D005139:Eyeglasses / Q000266:history*; D005858:Germany; D049673:History, 20th Century; D006801:Humans; D009885:Ophthalmology / Q000266:history* / Q000295:instrumentation; D012029:Refraction, Ocular