Editing Flashlight (section)

== Formats and specialized designs ==
{{Redirect-distinguish|Penlight|Light pen}}
[[File:Halogenlight.JPG|thumb|left|A medical [[Halogen lamp|halogen penlight]] to observe [[pupillary light reflex]]]]
[[File:LED-headlamp.jpg|thumb|An LED headlamp]]
A penlight is a small, [[pen]]-sized flashlight, often containing two [[AA battery|AA]] or [[AAA battery|AAA batteries]]. In some types, the incandescent light bulb has an integral [[lens (optics)|lens]] that focuses the light, so no reflector is built into the penlight. Others use incandescent bulbs mounted in reflectors.  LED penlights are becoming increasingly common. Low-cost units may be disposable with no provision to replace batteries or bulbs and are sometimes imprinted with advertising for promotional purposes.

A [[Headlamp (outdoor)|headlamp]] is designed to be worn on the head, often having separate lamp and battery components. The battery pack may be attached at the back of the head or in a pocket to improve balance. Headlamps leave the users' hands' free. A headlamp can be clipped to the brim of a hat, or built to mount on a [[hard hat]], instead of using straps; other types resemble eyeglass frames. Similar to the headlamp, an angle-head flashlight emits light perpendicular to the length of the battery tube; it can be clipped to a headband, belt, or webbing or set on a flat surface. Some types allow the user to adjust the angle of the head. The [[Fulton MX991/U Flashlight]] was an angle-head flashlight issued to US military personnel; similar style lights remain popular.

[[File:Non-sparking flashlight.JPG|thumb|Nonincendive flashlight for use when inspecting areas full of flammable gas]]

[[Tactical light]]s are sometimes mounted to a [[handgun]] or [[rifle]]. They allow momentary illumination of a target. They are small enough to be easily [[Weaver rail mount|rail-mounted]] to a gun barrel. Tactical lights must withstand the impact of recoil and must be easily controlled while holding the weapon.

[[File:Diving-torch.jpg|thumb|left|One style of diver's lamp]]

Although most flashlights are designed for user replacement of the batteries and the bulb as needed, fully sealed [[disposable]] flashlights, such as inexpensive keyring lights, are made. When the batteries are depleted or the bulb fails, the entire product is discarded.

Diving lamps must be watertight under pressure and are used for [[night diving]] and [[Scuba diving#Light underwater|supplemental illumination]] where surface light cannot reach. The battery compartment of a dive lamp may have a catalyst to recombine any hydrogen gas emitted from the battery since gas cannot be vented in use.

People working in [[Electrical equipment in hazardous areas|hazardous areas]] with significant concentrations of flammable gases or dusts, such as mines, engine rooms of ships, chemical plants, or [[grain elevator]]s, use "nonincendive", "intrinsically safe", or "explosion-proof" flashlights constructed so that any spark in the flashlight is not likely to set off an explosion outside the light. The flashlight may require approval by an authority for the particular service and particular gases or dusts expected. The external temperature rise of the flashlight must not exceed the [[Autoignition temperature|autoignition]] point of the gas, so substitution of more powerful lamps or batteries may void the approval.

[[File:Goose neck torch.jpg|thumb|left|Inspection light with flexible gooseneck mounting for lamp]]
[[File:Auroralighter.JPG|thumb|Flashlight in the shape of a gun (mid-20th century) from the permanent collection of the [[Museo del Objeto del Objeto]]]]

Inspection flashlights have permanently mounted light guides containing optical fibers or plastic rods. Another style has a lamp mounted at the end of a flexible cable, or a semirigid or articulated probe. Such lamps are used for inspection inside tanks, or inside structures such as aircraft. Where used for inspecting the interior of tanks containing flammable liquids, the inspection lights may also be rated as flame-proof (explosion-proof) so that they cannot ignite liquids or vapors.<ref>{{cite web |url=http://isddc.dot.gov/OLPFiles/FAA/010171.pdf |access-date=2012-01-09 |url-status=dead |archive-url=https://web.archive.org/web/20161111195440/http://isddc.dot.gov/OLPFiles/FAA/010171.pdf |archive-date=2016-11-11 |publisher=U.S. Department of Transportation |title=Advisory Circular 43-204 Visual Inspection for Aircraft |date=1997 |pages=96–100}}</ref>

[[Otoscope]]s and [[ophthalmoscope]]s are medical instruments that combine a hand-held light source and magnifying lenses for examination of the ear canal and eyes, respectively.

Aboard naval ships, battle lanterns may be used as emergency portable lighting. Installed in major compartments of the ship, a battle lantern can be detached from its mounting and used as portable lighting in the event primary lighting is out of service. Battle lanterns may use either incandescent or LED lamps and may have either disposable primary or rechargeable batteries.<ref>{{cite web |url=http://www.brooksidepress.org/Products/Military_OBGYN/Textbook/MilitaryOrganizations/BoxerTour/BattleLantern.htm |title=Battle Lantern |access-date=2017-03-26 |url-status=live |archive-url=https://web.archive.org/web/20170326230242/http://www.brooksidepress.org/Products/Military_OBGYN/Textbook/MilitaryOrganizations/BoxerTour/BattleLantern.htm |archive-date=2017-03-26 }}</ref>

Many flashlights are cylindrical in design, with the lamp assembly attached to one end. However, early designs came in a variety of other shapes. Some resembled [[candlestick]]s, with a bulb mounted at the top of a battery tube fixed to a flat base, with a handle. Many resembled [[lantern]]s, consisting of a battery box with a handle and the lamp and reflector attached to the front. Electric lanterns are used for lighting the broad area immediately around the lantern, as opposed to forming a narrow beam; they can be set down on a level surface or attached to supports. Some electric lanterns use miniature [[fluorescent lamp]]s for higher efficiency than incandescent bulbs. Portable hand-held electric spotlights can provide larger reflectors and lamps and more powerful batteries than tubular flashlights meant to fit in a pocket.

[[File:IPhone XR Flashlight.jpg|thumb|[[IPhone XR]] Flashlight]]
Multifunction portable devices may include a flashlight as one of their features, for example, a portable radio/flashlight combination. Many [[smartphone]]s have a button or software application available to turn up their screen backlights to full intensity or to switch on the camera flash or video light, providing a "flashlight" function.

In addition to utilitarian flashlights, novelty, toy, and ornamental portable electric lights have been made in a myriad of shapes; in the 1890s, one of the earliest portable battery light applications was a type of novelty porcelain [[tie pin]] with a concealed bulb and battery.