What happens at the “edges” of the visible light spectrum?

Question

We can “see” light between 380 and 700 nanometers, but what happens at the egde and just after that? I mean, when we approach the limit like 699-700-701-705…
Does it turn completely dark/invisible/something else immediately or is there some kind of gradual change?
Is it the same on both ends?

In: 17

Answer 1

You can look at a rainbow and see for yourself. Turn your hose on to a mist and spray it into the air during a sunny day. You will most likely need to spin around a bit to get the correct angle but there is a point where you will see the spectrum of colors like a rainbow.