Why do remote controls use infrared light instead of other wavelengths?

Question

Why do remote controls use infrared light instead of other wavelengths?

In: Technology

Answer 1

Related, some early remote controls used high frequency (15,000-20,000hz+) sound instead of light. The researchers developing the technology were mostly old (enough) men who’s hearing had degraded to the point that they couldn’t hear the remotes. Their young secretaries and lab assistants on the other hand *could* hear the sound of the remotes and *hated* them. The rise of transistors and IR LEDs are what finally killed this version of the technology.

Edit: These [early remotes](https://www.youtube.com/watch?v=PlgSuaIHYsY) are also where the slang “clicker” for remote controls came from due to the fact that some made a distinctly audible click.