Fresnel Lenses

A Fresnel lens is a compact optical lens designed to provide excellent light gathering ability in a lightweight package. Typically fresnel lenses consist of a series of concentric grooves etched in plastic, these grooves function as individual refracting surfaces that convert a light source into parallel rays, allowing the light to be seen over very long distances. These lenses can be manufactured with a large aperture and short focal length even while using much less material a conventional lens would require.

History of the Fresnel Lenses

Fresnel lenses were designed by French physicist Augustin Jean Fresnel, who sought to improve lighthouse illumination by replacing the reflectors being used with a ‘lens by steps’. Since a double convex lens of the size required would be far too heavy for his application, he proposed using a flattened design that would be both lighter and cheaper.

Since focusing power of a lens depends on optical surface curvature, he suggested reproducing the curvature of a double convex lens in sections, resulting in a lens that included all the surface area of the original— but with most of the thickness removed. The original lenses were made of glass, but most lenses today are manufactured from molded polymers.

As some light is scattered at each junction in a Fresnel lens, you will notice rings of light in the image plane. But though a Fresnel lens does not produce images of the same optical imaging quality as a traditional lens, its lightweight compactness means it is a good choice for many illumination and imaging applications.

Applications of Fresnel Lenses

Fresnel lenses are used today in a variety of light collection applications, such as illumination, imaging, projection and solar panels.

The glass Fresnel lenses of yesterday are no longer used in many lighthouses, but they have in many cases been replaced by aerobeacons, which often contain plastic Fresnel lenses. Fresnel lenses can also be found in the optical landing systems of aircraft carriers or naval air stations, in searchlights or flashlights, and in the lighting instruments used for theatre and motion pictures.

Imaging uses of Fresnel lenses include virtual reality headsets, retina identification cameras, and in automobiles as rear-view enhancers or to overcome the blind spots in trucks, especially when left-hand-drive trucks are driven on right-hand-drive roads or right-hand-drive trucks are driven on left hand drive roads.

While Fresnel lenses cannot be used for high-resolution projection, they are a good economical option for projection applications where a high-quality image is not essential. They can also be used to concentrate sunlight onto solar cells, lowering the cost and increasing the efficiency of a solar setup.

Custom Fresnel Lenses at Avantier

At Avantier we create custom optics for clients in a wide range of fields, from medicine and defense to research to industry. Whether you need a plastic Fresnel lens for a consumer application, a glass Fresnel lens for cutting edge research, or any other lens or optical component, we have you covered.