A Fresnel lens can be used to create a simple front-projection system. The lens enlarges the back-lit image it is placed against, and projects that image onto a surface, for example, a wall. A cell phone screen can be used with a Fresnel lens to make a front-projector, although the size of the enlarged image is restricted by the size of the cell phone's LCD screen. Supplies from a hobby store and from around the house are needed, but no special electrical or electronic skills are required.
Instructions
1. Place the shoebox horizontally on a work surface. Put the top cover on the shoebox. Measure the length of the shoebox using a tape measure. Cut the shoebox and top cover in half at the halfway mark using the blade of a utility knife.
2. Place one of the cut halves of shoebox and top cover aside. Stand up the cut half of shoebox so that the open end is facing down.
3. Place the Fresnel lens on top of the shoebox. Trace an outline around the Fresnel lens with a pencil. Remove the Fresnel lens.
4. Cut out the outline on the shoebox with the blade of a utility knife. Dispose of the cut out cardboard in the trash.
5. Turn the shoebox over so that the cutout is facing down. Place the Fresnel lens on the cutout with the grooved side of the lens facing out. Tape the sides of the Fresnel lens to the shoebox with strips of duct tape.
6. Place the shoebox right side up on the floor. Move the shoebox over so that it is a few inches from the wall, with the Fresnel lens side facing the wall. Stand the cell phone on the shoebox at the open end with its LCD screen facing toward the Fresnel lens. Tape the bottom of the cell phone to the shoebox with strips of duct tape.
7. Turn the cell phone on so that the LCD screen is lit up. Place the cut half of the top cover on the top of the shoebox. Turn off the lights. Move the shoebox toward and away from the wall until the image being projected on it is in focus.
Tags: Fresnel lens, cell phone, shoebox with, blade utility, blade utility knife, cell phone screen