Pinhole Viewer

WHAT TO DO

Draw a simple picture with the black marker and paper provided next to the box. Drawings made with simple, thick lines work best!

Open the lid of the box and put your picture in the clear plastic slot in front of the light bulb. Put the lid of the box back on making sure it is lined up correctly and no light is escaping!

Now look through the hole at the end of the box. What do you see? Slide the metal piece sticking out of the middle of the box to vary the size of the pinhole you are using. You can open the lid of the box and look at what is going on. Which pinhole creates the sharpest image? Which creates the brightest image?

HOW IT WORKS

You are seeing the images through a pinhole that is placed in front of the light bulb. The picture shows why the sharpness of the image depends on the size of the pinhole. A large pinhole lets through more light than a small pinhole, which is why the image is brighter. A large pinhole is not as precise as the small one however. The light rays can go through the top of the pinhole, the middle, or the bottom and they are able to spread out. With a small pinhole the light rays that go through the top, middle, and bottom are not as spread out and therefore the projected image is much more precise. Play with åUp-side down worldπ to explore why the image is flipped up-side down!