Robot Builder: The Beginner’s Guide to Building Robots

7. Harnessing Infrared

There is an invisible light that surrounds us—infrared, or IR. Its wavelength is below the visible spectrum, meaning that we cannot see this light without the help of technology.

The upside to this limitation is that we can stutter the light to transmit information. The 1s and 0s of digital communication represent a switch being turned on and off, and that works the same way with IR communications.

It is, however, a limited form of communication for the simple fact that the standard IR frequency is 38KHz, or 38,000 pulses per second, and most IR-decoding devices ignore all other frequencies of light. To make matters worse, the light doesn’t pass through walls or other obstructions, limiting it to line-of-sight applications ...