Humanity’s ways of providing a portable light source have come a long way since the days of the crude torch. With the invention of the flashlight by David Misell in 1899, humanity’s way of finding a bright spot in the dark became a lot easier. While modern flashlights are much more reliable than the crude “flash” of light provided by Misell’s invention over a century ago, modern day flashlights still provide a way to shed light on the world in areas where a traditional light source is either inaccessible or dangerous to use. The modern flashlight ranges from the small, dollar store AAA powered bulbs with colorful cartoon characters printed on the casing to industrial strength emergency response flashlights intended for use in hurricane response settings, and can come in an ever wider range of makes, models, bulb types, and power sources.
How it Works
The traditional flashlight uses the energy stored in dry-cell batteries or other forms of energy transference, such as a crank handle device that transfers kinetic energy into the flashlight’s internal electronics, generating a source of light. The batteries are connected to the light source, either a traditional incandescent bulb or another kind of light source, such as LED and mercury bulbs, by a conductor metal. The switch on the outside of a flashlight either completes or breaks the connection between the metal on the batteries and the metal base of the light source, which allows the flashlight to turn off and on. While flashlights operate off of some of the simplest electronic components, to the point where it is possible to operate a flashlight using a potato for a battery, the wide range of uses and types of flashlights outshines their simplistic technological components.
Types of Flashlights
Flashlights come in a wide range of designs, from lanterns, which are used in camping and low- electricity situations to provide a more constant overhead light, to handheld flashlights. The term flashlight also includes headlamps, which are most often used during outdoor activities such as hiking, camping, or in tight areas such as crawlspaces where holding a flashlight would be bulky or nearly impossible. For the most part, headlamps and lanterns can include incandescent and LED light options depending on the price range and intended purpose, while most other forms of lighting come in the form of a handheld flashlight.
The most common and cheapest option for a flashlight is the incandescent bulb. The incandescent bulb is the same kind of light source used by the original flashlight in 1899, and as such is much cheaper and widely produced than some of the other options for flashlights. However, due to the fragile nature of the filament inside of the bulbs, these flashlights are one of the most breakable ones and are not recommended for high-impact situations. Due to the need to produce heat to create light, these bulbs also end up draining the batteries of the flashlights much quicker than some other options, so for long term situations another form of flashlight may be more useful.
LED flashlights are a fairly new technology that is rapidly developing. While LED lights are most commonly associated with multi-color decorative lights and electronic screens, LED flashlights come in “white” light options that have a more bluish tone to them. LED lights are very battery efficient, as they do not require the production of heat to turn on. With the bulbs being much less fragile than the incandescent options, LED lights are a good mid-range price point flashlight for an emergency kit or a camping trip. The only downside of a LED flashlight is that many people find the bluish light very unnatural and it can cause headaches in individuals that are prone to migraines.
HID, Xenon, Halogen, and Krypton
High Intensity Discharge (HID) bulbs are much more bulky and expensive than LED bulbs. The light is created by ionized gas, and as such the mechanics for creating the flashlight tend to be more complex and more expensive than your average flashlight. However, HID flashlights provide an intense beam of light and are long lasting. They are often used in industrial and emergency situations to create a high powered, focused beam to light to search an area or provide a clear line of site to a safe point. Xenon, Halogen, and Krypton are flashlights that have a pressurized gas inside the bulb to help increase the lifetime of the bulb itself. This allows these kinds of flashlights to produce one of the brightest lights possible for a hand-held flashlight without draining the batteries. However, they are not nearly as durable or reliable as LED flashlights.
Crank and Shake Flashlights
While crank flashlights are slowly moving out of fashion, these incandescent flashlights produce and store light through sheer manpower. The lights are charged through a crank handle, which allows for the storing of a small amount of energy. The energy acts as a renewable battery source, allowing these flashlights to work in an environment where batteries are limited. The modern day replacement for crank flashlights are the shake flashlight, which uses a pair of magnets to generate energy when shaken near each other. The interactions of the magnetic fields allow for the generation of a small amount of energy that produces a weak source of light. While the lights provided are not nearly as bright as some of the other options, the shake flashlight does not require batteries, allowing it to be readily used without concerns of keeping batteries on hand.
Here is a YouTube video explaining how flashlights are made:
When picking out the right flashlight type, keep in mind the intended use. For a children’s sleepover, an incandescent bulb is a cheap, entertaining option. However, for a hurricane or tornado kit, or for everyday use on the job, consider looking into more durable lighting options.