Editing Nightlight

{{short description|Small light fixture used to provide dim illumination during the night}}
{{Other uses}}
[[File:LED nightlight with switch.JPG|thumb|An [[LED]] nightlight]]
A '''nightlight''' is a small [[light fixture]], usually electrical, placed for comfort or convenience in dark areas or areas that may become dark at certain times, such as at night or [[Emergency light|during an emergency]].  Small long-burning [[candle]]s serving a similar function are referred to as "[[tealight]]s".

== Uses and cultures ==
People usually use nightlights for the sense of security which having a light on provides, or to relieve [[fear of the dark]], especially in young children. Nightlights are also useful to the general public by revealing the general layout of a room without requiring a major light to be switched on, for avoiding tripping over stairs, obstacles, or pets, or to mark an [[fire exit|emergency exit]]. Exit signs often use [[tritium radioluminescence]]. Homeowners usually place nightlights in bathrooms, kitchens and hallways to avoid turning on the main light fixture, especially late at night, and causing their eyes to adjust to the brighter light.<ref name="nsf">{{cite web|url=http://sleepfoundation.org/bedroom/see.php|publisher=National Sleep Foundation|title=National Sleep Foundation|access-date=June 23, 2015|archive-date=February 1, 2019|archive-url=https://web.archive.org/web/20190201143331/http://sleepfoundation.org/bedroom/see.php|url-status=dead}}</ref>

Some frequent travelers carry small nightlights for temporary installation in their guestroom and bathroom, to avoid tripping or falls in an unfamiliar nighttime environment. [[Gerontologist]]s have recommended use of nightlights to help prevent falls, which can often be life-threatening to the elderly.<ref name="McMurdo">{{cite journal |last1=McMurdo |first1=M E|last2=Gaskell|first2=A|title=Dark adaptation and falls in the elderly |journal=Gerontology |date=1991 |volume=37 |issue=4 |pages=221–4 |doi=10.1159/000213264 |pmid=1916313 }}</ref>

The low cost of nightlights has enabled a proliferation of different decorative designs, some featuring [[superhero]]es and fantastical designs, while others feature the basic simplicity of a small luminous disc.

The 1990 song "[[Birdhouse in Your Soul]]" by [[They Might Be Giants]] is a song sung from the perspective of a nightlight.<ref name="ReedSandifer 2014">{{cite web|url=https://slate.com/culture/2014/02/a-history-of-the-they-might-be-giants-song-birdhouse-in-your-soul.html|title=Blue Canary in the Outlet by the Light Switch, Who Watches Over You?|first2=Elizabeth |last2=Sandifer |first1=S. Alexander |last1=Reed|date=February 13, 2014|website=Slate Magazine}}</ref>

==Light source and variants==
[[File:NightLight.jpg|thumb|[[Electroluminescent]] nightlights use little electrical power]]
Early electrical nightlights used small [[incandescent lamp]]s or small [[neon lamp]]s to provide light, and were much safer than small candles using an open flame. The neon versions consumed very little energy and had a long life, but had a tendency to flicker on and off (reminiscent of a candle), which some users liked and others found annoying. In the 1960s, small nightlights appeared that featured a low-power [[electroluminescence|electroluminescent panel]] emitting soft green or blue light; similar lights are still available today.<ref name="Edison">{{cite web|title=Electroluminescent Lamps - How They Work & History|url=http://www.edisontechcenter.org/electroluminescent.html|website=www.edisontechcenter.org|access-date=2017-02-16}}</ref>

Some nightlights include a [[photocell]], which enables them to switch off when the ambient light is sufficiently bright. Other designs also feature a built-in [[passive infrared sensor]] to detect motion, and only switch on when somebody is passing by in the dark. With the availability of low-cost [[LED]]s, many different variants have become available, featuring different colours, sometimes changing automatically or in a user-controllable way.

==Safety hazard==
The [[US Consumer Product Safety Commission]], or UCPSC, reports it receives about 10 reports per year where nightlights close to flammable materials were cited as responsible for fires; they recommend the use of nightlights with [[LED lamp|LED bulbs]] cooler than the four or seven watt incandescent light bulbs still used in some older products.<ref>{{cite web | url= http://www.cpsc.gov/cpscpub/pubs/5063.html | title= Fire Hazard with Nightlights | work= CPSC Document #5063 | publisher= [[US Consumer Product Safety Commission]] | access-date= May 12, 2011 | archive-url= https://web.archive.org/web/20110813013351/http://www.cpsc.gov/cpscpub/pubs/5063.html | archive-date= August 13, 2011 | url-status= dead }}</ref>

== Potential health issues and benefits==
A [[University of Pennsylvania]] study indicated that sleeping with the light on or with a nightlight was associated with a greater incidence of [[nearsightedness]] in children.<ref>{{cite web |url=http://www.sciencenetlinks.com/pdfs/nearsight_actsheet.pdf |title=Is Nearsightedness in Children Linked to Night Light Exposure During Sleep Before Age Two? |access-date=March 23, 2009 |publisher=[[American Association for the Advancement of Science]] |work=Science NetLinks |archive-url=https://web.archive.org/web/20081203153541/http://www.sciencenetlinks.com/pdfs/nearsight_actsheet.pdf |archive-date=December 3, 2008 |url-status=dead }}</ref> However, a later study at [[Ohio State University]]<!--Wikipedians do not use "The" as part of Ohio State's name; it is considered a marketing gimmick, and routinely deleted.--> contradicted the earlier conclusion.<ref>{{cite web|url=https://www.sciencedaily.com/releases/2000/03/000309074442.htm| title= Night Lights Don't Lead To Nearsightedness, Study Suggests| access-date=March 23, 2009| publisher=[[Science Daily]] | date=March 9, 2000}}</ref> Both studies were published in the journal ''[[Nature (journal)|Nature]]''.

Another study has indicated that sleeping with the light on may protect the eyes of diabetics from [[diabetic retinopathy|retinopathy]], a condition that can lead to blindness.<ref>{{cite web|url= http://www.webmd.com/content/article/48/39153.htm|title= Light at Night Protects Diabetics' Eyes|access-date=March 23, 2009| publisher=[[WebMD]]| date=June 27, 2002 }}</ref>  However, the initial study is still inconclusive.

The optimal sleeping light condition is said by some to be total darkness.<ref>{{cite web|last1=Rettner|first1=Rachel|title=Avoiding Depression: Sleeping in Dark Room May Help|url=http://www.livescience.com/9004-avoiding-depression-sleeping-dark-room.html|website=Live Science|date=17 November 2010 |access-date=23 June 2015}}</ref> If a nightlight is used within a sleeping area, it is recommended to choose a dim reddish or amber light to minimize disruptive effects on sleep cycles.<ref name="Hyman">{{cite news|last1=Hyman|first1=Mark|title=How a Light Bulb Can Help You Sleep Better|url=http://www.huffingtonpost.com/dr-mark-hyman/light-sleep_b_4239765.html|access-date=2017-02-16|work=The Huffington Post|date=8 November 2013}}</ref><ref name="nsf" /> In addition, nightlights may be useful in locations other than sleeping areas, such as hallways, bathrooms, or kitchens, to allow late night trips to be made without turning on the full light, while preserving a dark sleeping environment.<ref name="McMurdo" />

==References==
{{reflist}}

== External links ==
* {{wiktionary-inline}}
* Example of stylized night light: https://galaxsleep.com/

{{Artificial light sources}}

[[Category:Light fixtures]]
[[Category:Night|Light]]