It's time to experiment and see what colours you can generate. Have fun and send us you photos and comments. If you have any questions please email t...
In this tutorial we will build a physical RGB (red, green, blue) LED (light emitting diode) colour mixer using Bare Conductive Paint. Each RGB LED has three internal light emitting diodes (LEDs) for each of the colours - red, green and blue. Further there is a lead to connect and control each of these internal diodes. Thus you can mix these three and get a whole range of new colours. The diagram below shows what one would commonly find inside a RGB LED.
Step 1: RGB LED Internal Diagram
You can see that pin 2 is the three internal LEDs negative lead or cathode and 1, 3 and 4 are each of their respective positive leads or anodes. We are going to physically control the RGB LED by making Bare Paint Potentiometers for each of its positive leads instead of using static resistors. Thus by altering the resistance we will ultimately change the current flowing into each diode and affect its brightness. This is a fairly crude way to control LEDs. There is a more elegant way to do this using an Arduino and PWM (pulse width modulation). We will cover this in another tutorial.