The PIR Fresnel lens, called magnification sheets, has numerous uses, from the start of fires to preventing car accidents. A positive lens focuses a larger area of light on a small focal pointbut the type used here is a negative lens. The light is bent slightly through concentric prismstiny slits cut into the plastic. This makes the area outside the Fresnel lens natural viewscape above in view through the lens, similar to the shape of side mirrors allowing the driver to see an area larger than the size of the mirror. This reduces the area that would normally be a blind spot and can reduce accidents. Pure water will adhere a thin plastic negative Fresnel lens to a window. Things you will need:
- Auto Glass Cleaner
- Paper Towels Fresnel Negative Plastic
- Water Spray Bottle
- Cloth Lensor Old Credit Card
See More Instructions
- Prepare a window for mounting a negative Fresnel lens by washing with a glass cleaner.
- Clean the inside of the car’s rear window thoroughly with a car glass cleaner and paper towels.
- Water holds a Fresnel lens on a window.
- Rinse the glass cleaner off the window surface to remove any residue. Spray the window with water and use paper towels to remove the rinse water. Then spray the window with a light mist of clean water.
Look through the plastic Fresnel 3Dlens on both sides. Make sure you have the lens facing you in such a way that it will magnify what is seen through it, giving you a broader view. If you look through it from the opposite side, things will appear smaller. You want to see through it in the direction that makes things seem bigger.
Place the plastic Fresnel lens on the inside surface of the car rear window. Start at the center of the lens and press to the surface of the window. Press any bubble out toward the edges of the lens. Use the squeegee or an old credit card if necessary.
Remove the lens, just peel it off the window. Repeat these steps to replace it.A consequence of the soft-edged lens is a certain amount of light scattering outside the main beam, which can be disturbing on the set (especially on the legs or behind the scenes) adjacent to the focus. This light scattering can be reduced, and some control of the beam shape gained, by attaching a four-leaf visor to the front of the spotlight. Because the fresnel lens gives light with soft, diffuse edges, its use is limited to the space behind the proscenium.
Fresnel lens in cinema
Fresnel lenses are designed for lighting applications in television, cinema and theater, either for application in “spot” spotlights (concentrated light) or “flood” spotlights (light forming a 60 ° fan). ). The Fresnel lens should be convex in shape in order to get the lamp as close to the lens as possible. For applications where very high thermal loads occur, special hardened Fresnel lenses are used. The light characteristics remain unchanged: smooth, uniform and blurred at the edges.