acuity of 0.1 is sufficient for a person to be able to orientate themselves outdoors. However, a visual acuity of 0.8 is required for reading travel timetables. Other minimum values include: 0.4 for watching [...] watching television, 0.5 for reading the newspaper and 0.7 for reading a telephone directory. Is the ability of the eye to read solely dependent on visual acuity? No. In order to be able to read we require [...] Vario Plus system and use it at the same time? No. For technical reasons, it cannot be used during the 4-hour charging period. What is a dioptre? A dioptre (dpt) is the unit of measurement of the optical power