Pinhole patterns Prediction: What will you see if you put a card with a small hole in it between the bulb and a piece of paper as a screen? Use a pencil to punch a small hole in a note card and put the card about halfway between the light source and the screen so that the pencil hole is about 30cm from the bulb. Examine the pattern formed on the screen. What do you see? Is the pattern upside down or right side up with respect to the lament itself? Is it ipped right to left? (You can tell by holding a pencil in mm of the bottom part of the bulb and seeing where it appears on the screen.) How is the pinhole pattern different from an image produced by a lens? To help explain what is happening with the pinhole, draw rays coming from different parts of the lament. Show some that make it through the hole to the screen as well as some that are stopped by the card. Card with hole screen Use your diagram to explain how pinhole patterns are formed. Hint: Where does lightom the top parts ofthelament end up? Prediction: What would you see if the card had three holes in it instead of one? Try it. What do you see? Prediction: What will happen to the patterns if you move the screen closer and farther from the holes? Try it. What happens to the patterns