Even today, it is sometimes necessary to view a filmstrip or slide. A modern office video projector is unsuitable for this, and its cost is prohibitively high. A homemade projector will help you get out of the situation.
Instructions
Step 1
Use a regular drawing ruler as an impromptu optical bench. Using the bracket, fix the tubular battery lamp to it strictly horizontally.
Step 2
Take several identical small collecting lenses. Insert them into a tube of a suitable diameter. Install this tube in front of the lantern. Also fix it with a bracket strictly horizontally.
Step 3
Make a frame for installing a slide or filmstrip advance from any suitable material. The main requirement for it is that it does not scratch the carrier in any way. Place it in front of the lens tube strictly vertically.
Step 4
Use a large magnifier as a lens. Place it on a bracket of such a structure that allows movement along the ruler. The center of the magnifier should be aligned with the center of the frame on the filmstrip or transparency.
Step 5
Darken the room completely and turn on the flashlight. If using a diaphragm, place the ruler sideways, otherwise the frame will be rotated 90 degrees. Point the projector at a wall. Focus the image by moving the lens along the ruler. Please be aware that as the distance from the wall to the projector increases, the image size increases and the brightness decreases. Re-focus each time this distance is changed.
Step 6
If the image turns out to be mirrored, turn the frame with the slide or filmstrip to the opposite side of the lens.
Step 7
Light from the flashlight can hit the screen past the wearer, thereby degrading the contrast of the image. To prevent this, use a casing of any design.
Step 8
If you are going to use the projector often, for example, to show filmstrips and slides to children, use rechargeable batteries or an AC adapter with suitable parameters to power the flashlight instead of batteries, and hang a white screen made of any material on the wall.
