Evanescent field

Ok kiddo, when light travels through different materials, it can get blocked or absorbed by them. But sometimes, it can leave behind something called an evanescent field.

Imagine a wave in a swimming pool, when it reaches the edge, it creates small ripples that don't go very far, but you can still feel them if you are close enough. The same thing happens with light. When it hits the boundary between two materials, it creates a tiny ripple of light that only goes a short distance, but it's still there, and we call it the evanescent field.

Scientists use these evanescent fields to study and manipulate things that are too small to see with the naked eye, like molecules or cells. They can focus the evanescent field on a specific area and use it to move or change things without actually touching them.

So, to sum it up, an evanescent field is like a little ripple of light left behind when light hits the boundary between two materials, and scientists use it to do very important and cool things!