We look at the world with receptors (normally we call them "eyes") that are sensitive to a limited range of electromagnetic spectrum (390 up to 700nm wavelength, or, if you prefer, 430-770 THz). Light is absorbed and reflected by objects surfaces in different ways, depending on the texture of the surface and its chemical characteristics. It is this reflection that provides the images to our eye (and brain). Different objects surfaces create different reflections, hence we perceive different images.
If we had receptors sensitive to different spectrum we would see different images. Not all animals have the same visual spectrum, hence different animals perceive the world differently. If you wander what animal is the one with the best receptors in terms of broadest range, it is not us but a shrimp, the Mantis Shrimp see photo. It has 12 different kind of receptors, we have only got 3, and it can see much more spectrum than we do (see graphic).
Luckily we have technology. And technology can let us see what our eyes cannot see.
Now researchers at the Washington University have come up with a camera that can detect a wider range of spectrum, beyond the RGB that normal digital cameras are designed to capture (because it correspond to the spectrum we see).
The camera is composed by a sensors and a lamp that can flash light at different wavelengths, see the clip. This produces different reflection from the object surface that are captured by the camera sensor. A software analyses the different images and create an image that is a composition of them all, giving emphases to those characteristics that are invisible to our eyes. Obviously, the software converts those wavelengths that are outside of our visual spectrum into wavelengths that we can see.
The results are impressive. As shown in the clip the veins in our arm pops up, clearly visible. Also nice the possibility to tell if an avocado (or any other fruit...) is ripe. Well, that would really help me at the supermarket!
The good thing is that what is now a special camera should become an add-on to our phone camera. At that point we will have in our hands a Superman vision... beating the Mantis shrimp!