Bathroom vent light – Bathrooms interior ventilation is performed with a conduit to the cover (shunt) without problems. In the case of not having access to the cover can lead extraction through a conduit for false ceiling and out through an exhaust Crane (exactly as does the extractor fan in the kitchen), which would connect either with light or no timed.
The bathroom vent light, if an interior bathroom, it can only be done by artificial elements (lamps). There are enough technical solutions to bring light to an interior space with light wells, which through an opening to the exterior, chimney type, is installed inside a tube of mirrors that directs the light from the outside to the inside and simulates a skylight . But these mechanisms need enough space duct and they are relatively costly economically.
The windows are important: open a room bring the outside in and let the bathroom vent light naturally. If a residential space with missing windows makes you feel like you’re living in a cave, there is a much cheaper solution than adding a true window to one of your walls: create a fake window that you can make yourself and emit light the same way that a real window.