Schematic illustration of a magnifying glass.

Comb Rays

How Does a Magnifying Lens Affect Light Rays?

 

Materials

  • 4-in. (10-cm) circle cut out of cardboard
  • pencil
  • masking tape
  • comb
  • sheet of white paper
  • flashlight
  • magnifying lens

Try This

  1. Poke a hole in the center of the cardboard circle with the pencil point and enlarge the hole with the pencil shaft.
  2. Tape the comb over the hole.
  3. Lay the sheet of white paper on a table.
  4. Lay the flashlight next to the sheet. Position the cardboard circle between the flashlight and the sheet so the light shines through the hole.
  5. Darken the room.
  6. Hold the magnifying lens against the edge of the sheet so the light shines through it. What happens to the rays of light?

What's Going On?

Made of glass, the magnifying lens is a double convex lens, a lens that is thicker in the middle than around the edges. It bends the light rays, so they spread out, making an object look much larger when the light reaches your eyes.

Schematic illustration of poking a hole in the center of the cardboard circle with the pencil point and enlarge the hole with the pencil shaft.