Bureaucrats, confirmed, developer, Administrators
195
edits
Difference between revisions of "Flashlight Basics"
Jump to navigation
Jump to search
remove link
(→The Switch: add Surefire switch) |
(remove link) |
||
| (6 intermediate revisions by 4 users not shown) | |||
| Line 1: | Line 1: | ||
A flashlight (or "torch" for some English speakers) is a handheld light source powered by batteries. | A flashlight (or "torch" for some English speakers) is a handheld light source powered by batteries. | ||
[[File:Flashlight-parts.jpg|thumb|left|800px|Disassembled flashlight with parts labeled. Click image for a larger version.]]<br clear=all> | |||
== Light Source == | == Light Source == | ||
| Line 9: | Line 12: | ||
Most flashlights include a reflector around the light source to gather the light and focus it out the front. Reflectors have a parabolic shape which can take light rays emitted from a light source in the parabola's focal point and send the reflected rays all in the same direction (rays that go out the front without hitting the reflector will provide some spill). A bigger, deeper reflector is able to focus the light into a smaller hotspot and offer more throw and less spill. Smaller lights are easier to carry in a pocket but will generally have more floody light. [[Mag Instrument]]'s Maglites have a reflector that moves with respect to the light source allowing a variable focus that can yield a wider flood or a tighter spot of light. | Most flashlights include a reflector around the light source to gather the light and focus it out the front. Reflectors have a parabolic shape which can take light rays emitted from a light source in the parabola's focal point and send the reflected rays all in the same direction (rays that go out the front without hitting the reflector will provide some spill). A bigger, deeper reflector is able to focus the light into a smaller hotspot and offer more throw and less spill. Smaller lights are easier to carry in a pocket but will generally have more floody light. [[Mag Instrument]]'s Maglites have a reflector that moves with respect to the light source allowing a variable focus that can yield a wider flood or a tighter spot of light. | ||
Usually there is a flat glass or plastic lens over the reflector. Better lights have glass lenses with anti-reflective coatings that allow more of the light to pass through the lens rather than bounce back into the light (even better than plain glass). But some lights have a curvilinear lens that concentrates the light similar to a reflector. And still other lights let you move this lens and go from flood to throw, similar to Maglites. | Usually there is a flat glass or plastic lens over the reflector. Better lights have glass lenses with anti-reflective coatings that allow more of the light to pass through the lens rather than bounce back into the light (even better than plain glass). But some lights have a curvilinear lens that concentrates the light similar to a reflector. And still other lights let you move this lens and go from flood to throw, similar to Maglites. See [[lenses]] for more options. | ||
== Batteries == | == Batteries == | ||
| Line 21: | Line 24: | ||
== Driver == | == Driver == | ||
In the head of a LED light there might be a [[driver]] which regulates the voltage from the batteries to some value optimal for the light source. For instance many | In the head of a LED light there might be a [[driver]] which regulates the voltage from the batteries to some value optimal for the light source. For instance many LEDs need a voltage of about 3.6 volts, so if you only have one AA battery (1.2 to 1.5 volts), the driver will need to boost the voltage to something the LED can use. The driver also can control different brightness levels to the light and special modes for SOS or strobe functions. Incandescent flashlights are often driven directly by the batteries without a driver. | ||
== More Options == | == More Options == | ||
Flashlights themselves can take different forms, including head lamps, and can be made of plastic, aluminum, stainless steel, or titanium (see [[materials]]). There are many different kinds of light sources and | Flashlights themselves can take different forms, including head lamps, and can be made of plastic, aluminum, stainless steel, or titanium (see [[materials]]). There are many different kinds of light sources and LEDs that can be used too. | ||