A flashlight is a good a useful tool to make a sliding projector
Building a slide projector for a science project is a fun and rewarding process. This is because the slide projector can be used after the project has been evaluated and returned to the student. A homemade slide projector focuses on the scientific areas of physics, light rays and the uniqueness of lenses. This makes it an ideal science project.
Instructions
1. Remove the lens from the flashlight that protects the light bulb.
2. Place the flashlight on a flat lumber plank. If necessary, use a small book or a block of wood to level the flashlight at the end. It should be completely parallel to the plank. Tie the flashlight to the plank using string or tape so it does not roll around. Place the plank so the light beam shines onto a white wall.
3. Measure the width of each lens. Write the measurements down.
4. Make two posts for the lenses using two small pieces of lumber. The posts should measure 4 inches wide, 2 1/2 inches deep and 2 1/2 inches tall. Use the saw to cut the posts. Create a small groove on the top of each lumber post using the saw. The groove should be 1/10 of an inch smaller than the measurement collected in step 3. Each groove should be approximately 1/2 inch to support the lenses.
5. Make an additional post for the slides using the same measurements as the posts in step 4. When done, test to see if the slides can easily slide through the groove. Use sandpaper the make the groove smooth.
6. Attach the concave lens in front of the flashlight beam on one post by squeezing it lightly into the tight groove. Place the convex lens in between the concave lens and the front of the flashlight on another post in the same manner. Both lenses should be exposed to the flashlight's beam and placed with at least one foot between the first lens and the flashlight. Do not secure the posts to the wooden plank holding the flashlight.
7. Place the third wood post for the projector slides in between the convex lens and the flashlight. Do not secure it permanently.
8. Place the photographic slides in to the projector slide post. Turn the flashlight on and point the beam through the slide and the two lenses. The slide should project upon the white wall.
9. Adjust the flashlight beam and the positioning of the lenses by moving them back and forth until the slide projection becomes a clear and sharp image on the wall. This may require moving the lenses closer to the flashlight or farther away from it, depending on the original placement of them. It also depends on the strength of the flashlight beam. Continue moving the lenses until the image is clear. Secure the posts when the adjustments are complete by applying glue to the bottom of the posts and pressing them down on the plank until dry.
10. Write down the distance between the wall and the homemade slide projector. This measurement needs to be known when presenting the science project in school. The image should be as clear and crisp during the presentation as it was when you used it at home.
11. Tape the slides together that will be viewed when presenting the projector. The groove made in the wooden post will allow several slides to slide through the post. When presenting, turn off the lights so the slides stand out more.
Tags: flashlight beam, science project, concave lens, concave lens front, convex lens, flashlight secure
