Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
A61B3/00—Apparatus for testing the eyes; Instruments for examining the eyes
A61B3/02—Subjective types, i.e. testing apparatus requiring the active assistance of the patient
A61B3/028—Subjective types, i.e. testing apparatus requiring the active assistance of the patient for testing visual acuity; for determination of refraction, e.g. phoropters
A61B3/04—Trial frames; Sets of lenses for use therewith