Nightlight
Encyclopedia : N : NI : NIG : Nightlight
A nightlight is a small, usually electrical, light source placed for comfort or convenience in indoor dark areas or areas that become dark at certain times.
Use and culture
Children often use night lights for the sense of security they provide them. Besides their usefulness to children in the allaying of their fears, night lights are also useful to the general public for allowing sight of the general lay of a room without turning on a major light, for avoiding tripping on a case of stairs, or to mark an emergency exit; the exit signs often use tritium in the form of a traser.
There are a wide variety of nightlights. Most based on incandescent bulbs have a power usage of less than 10 watts; lights based on more efficient technologies, e.g. neon lamps and LEDs, use 1 watt or less. They sometimes have a light-sensitive switch which activates them only when it is dark enough for them to be required. Some others even include an integrated rechargeable battery so that the light will continue to function during power outages.
Nearsightedness
At least one study [link], at the University of Pennsylvania, indicated that sleeping with the light on or with a night light was associated with a greater incidence of nearsightedness in children. A later study [link] at Ohio State University, however, contradicted the earlier conclusion. Both studies were published in the journal Nature.
From Wikipedia, the Free Encyclopedia. Original article here. Support Wikipedia by contributing or donating.
All text is available under the terms of the GNU Free Documentation License See Wikipedia Copyrights for details.