A LED flashlight produces light through light emitting diodes (LEDs) rather than an incandescent bulb, making them cooler, more energy efficient and tougher.
Incandescent light used in traditional flashlights utilizes a filament wire encased in a glass vacuum tube or bulb. When electricity is supplied to the wire from the batteries, the wire glows with heat that produces light. The heat, however, is not only lost energy but it eventually burns out the wire and the bulb must be replaced.
A LED flashlight harnesses light created by an entirely different process. Two types of semiconductor materials are used in a LED: one type that has an abundance of free electrons and the other that has a deficit. When enough energy is supplied in the form of electricity, a threshold is reached that pushes some of the free electrons in the abundant material to jump to the attracting material. When that electron takes its place in the new material a photon or particle of light is released.
The color of the released light is dependent on what kinds of materials are used and how much energy is required for the electrons to make the jump. If a low amount of energy is required the light emitted will be in the infrared or red wavelength. If a comparatively high threshold much be reached, the light emitted will be up in the blue/white wavelength.
OLED or organic light emitting diode, is a newer technology that uses carbon based materials rather than synthetic materials. OLED is well suited for display screens and will likely replace LCD technology, but OLED flashlights may or may not come to pass.
LED flashlights come on many different sizes and candle powers as do regular flashlights. The number of LEDs in the flashlight will determine its brightness. LEDs are coated with a clear solid resin, making them nearly indestructible. If you drop a LED flashlight the chances are slim that any damage will occur. Many LED flashlights are also waterproof.
A LED flashlight draws only 5-10% of the power of an equivalent light bulb, conserving batteries and saving money. It can also hold up under 5-10 years of continual use!
The light from a LED flashlight is pure, bright and true and can be seen for up to 1 mile (1.6 kilometers). Unlike incandescent bulbs that produced rings of brighter light within the scope of the beam, LED beams are evenly illuminated, like fluorescent light.
One type of LED flashlight does not even require batteries. Based on the Faraday Principle of Electromagnetic Energy, a copper wire is encased in a magnetic field inside the flashlight. By shaking it vigorously for 15-30 seconds, enough electricity is generated to produce light for about 5 minutes. If you need light beyond that period, you simply shake the flashlight again. This product has no replaceable parts and is a great emergency light.
A LED flashlight might cost a little more than a traditional flashlight, but the money saved in batteries and bulbs will offset that cost. It is nearly indestructible under normal use, is more environmentally friendly, can be waterproof, and emits purer, truer light. With all of these advantages it's clear that LED technology is lighting our way to a brighter future.