How Does It Work
Your phone is upside down when you put it into the box and the magnifying glass is a lot smaller than the image on the screen. It just seems a little weird, right? Think about the upside down phone. You probably know that, inside their eyes, humans “see” images of the world upside down. Well, they would be without corrections made by your brain. The Homemade Projector can help visualize this concept. The human eye has a lens in it similar to the magnifying glass that’s attached to your projector. The lens on the box flips images right side up as they pass through it going from the upside down phone to the screen. Your eye flips images coming from what you see so they’re upside down. While your brain flips the image to its correct orientation, the wall doesn’t. That’s why you have to set your phone in the box upside-down. You have to out-think your thinker.
But, how about that image on the screen? It’s way bigger than the lens in the magnifying glass! This works because of the shape of the lens and the fact that light travels in straight lines. A convex lens has a shape where the middle is thicker than the edges, rather than a concave lens which is thinner in the middle than at the edges. The shape of a convex lens allows it to catch, bend, and focus more light coming from the phone inside the box.
Once you have a dark enough space by darkening the “theater,” the magnifying glass will gather, focus, and project the light coming from the phone to the screen and you see images. Thanks to your Homemade Projector!
