Through a transparent medium a double refraction can be considered. If we think of a window glass, the light undergoes a first refraction when passing from the air to the glass, continues on its way and refracts again when it passes back into the air.
The science of light has helped us understand and know what certain objects we could not see were like. Thanks to the interaction of objects with light we can know their shape and, on certain occasions, the material of which they are made up. The ALBA Synchrotron uses a very bright light, called synchrotron light, to study matter, like you have just done yourselves. But it uses devices much more complicated than a flashlight to generate it! CAN YOU SEE THE DIFFERENCE BETWEEN THE SHADOWS PROJECTED BY OPAQUE, TRANSLUCENT AND REFLECTIVE OBJECTS? Yes, it is abysmal the difference between they. HOW DOES LIGHT HELP US KNOW ABOUT OBJECTS THAT WE CANNOT OBSERVE DIRECTLY? It help us reflecting the light to our eyes see the difference objects