How to make a model camera?

1, find a convex lens (the stationery store can have a magnifying glass);

2. Roughly measure the focal length L of the convex lens

3. Find a suitable paper box with a width a less than l..

4. According to the size of the convex lens, cut a round hole on one side of the paper box and a slightly larger square hole on the other side;

5. Cover the square hole with translucent plastic film (in the supermarket);

6, lens production: roll up the convex lens with slightly thick opaque paper, the length is about equal to L-a, and install the convex lens at one end.

7. Make another round paper tube with a slightly smaller diameter than the lens. Cut 10 small openings vertically along the height direction at one end and spread them out. Like sunflower, insert this paper tube into the round hole of the carton and stick the cut part on the inner wall of the carton;

8. Put the lens on the paper tube, and you can see the distant scenery (inverted image, reduced) from the plastic film with square holes.

9, adjustment, if the scene is not clear, you can adjust the length of the paper tube and lens, cut off a circle appropriately.

Try to be your favorite model camera.