Star Trek: 10 Things You Didn't Know About Geordi's VISOR

10. What Geordi Can See

The colours that Humans see are actually just different wavelengths of electromagnetic radiation, with red being the longest (at around 700 nanometres), and violet the shortest (at around 380 nanometres). However, visual light is only a small segment of the electromagnetic spectrum. Longer wavelengths contain types of radiation like infared light, microwaves, and radio waves, and shorter wavelengths contain types like ultraviolet light, X-rays, and gamma rays. With his VISOR, Geordi was able to see much more of the electromagnetic spectrum, meaning he could detect heat by looking at infared light, and sometimes see through objects or clouds that would appear opaque for anyone else.

He also saw the world in much more detail than the average person. He could detect tiny details in people's heart rates and perspiration, which sometimes even allowed him to tell if someone was lying.

Several scenes have given us representations of Geordi's way of seeing, but with ordinary Human eyes, it's actually physically impossible to even comprehend what it would be like to see anything other than visible light.