from one another, whereby the mode of action has an angled progression. Which range of light waves is visible to the eye? The light which is visible to us has a wavelength in the range of 380 nanometres [...] instructions. If in doubt, please ask your optician for help. Can I charge the battery handle of the Vario Plus system and use it at the same time? No. For technical reasons, it cannot be used during the 4-hour [...] the reciprocal value of the focal length of a lens measured in metres: a power of +5 dpt therefore has a reciprocal length of 1/5 metres or 20 centimetres. What is long-sightedness? In the case of long