In this Instructable, we will go through the steps of getting our first LED project completed. The idea is to make a simple 'flashlight' while dabbling our feet, ever so gently, in the waters of electronic hardware. The hope is to get to know a little bit of the theory of operation, while actually making a functioning device. We hope you enjoy it!
Difficulty level: Beginner
Time to completion: 15-20 Minutes
Step 1: Overview
- Batteries (aka Power Supply)
- Light bulb (aka Light Source)
- Casing (aka Body)
For our purposes, we'll only need two modes of operation (on/off) so we'll ignore the 'flashing mode electronics' included in modern LED flashlights.
Power Source: as we know, batteries provide the electricity that turns the bulb on. Everyday batteries (like those inside the TV remote) are made using specific materials that, when combined, are able to store and supply energy. The energy is stored in a chemical form, and it is supplied (discharged) in an electrical form. By connecting the battery ends (terminals) to some specific materials, we can convert the discharged electric energy into light.
Light Source: there are many different ways to produce light, but the most common are by means of fluorescence or incandescence (heat). The bulbs inside older flashlights contain a small filament that heats up when electricity passes through. And so, when the path of electricity discharged from the battery goes through the filament it heats up and emits light. This heat-to-light effect is due to the properties of the filament's material. Those of us with electric kitchens can witness this effect when the stove elements get really hot. Different to the incandescent bulbs, LEDs turn electrical energy into light by means of an electrical/optical process known as electroluminescence.
Switch: much like the light switches in our households, the switch on a flashlight controls the discharge of electric energy from the batteries to the light bulb. It is not essential for the operation of the flashlight, but it provides a convenient way to turn it on and off (an alternative would be to plug/unplug the connection between the battery and bulb).
Casing: the casing or body of a flashlight offers a convenient way to keep all the components in place. It also provides a little protection against expected and unexpected changes in the surroundings.
With all necessary components identified, we can now go about purchasing them to get our project started.