Definition of an Aspherical Lens

Aspherical lenses are small and efficient.

Traditional lenses are made from the curved surface of a glass or plastic sphere. Aspherical lenses, on the other hand, are made by using special molded glass, and although they still have a curved surface, they are not entirely spherical.

Definition and How They're Made

Aspherical lenses are lenses made by heating optical glass until it can be placed into heat-resistant molds. Manufacturers then create individual variations of aspherical lenses.

Shape Of The Lens

Although aspherical lenses have curved surfaces, they do not share the same shape as traditional lenses. This difference in shape makes an aspherical lens more precise, and with fewer visual aberrations, than a spherical lens.

Uses

Aspherical lenses have been mostly used in eyeglasses, but in the past 30 years, they have been developed to be used for high-quality photography and as a standard for smaller photographic and video cameras.

Unique Features

Thanks to their smaller size, aspherical lenses have a thinner center, which makes them much lighter. Manufacturers can adjust the shape of the lenses while creating them, allowing for adjustments to each lens's focal power and clarity.

Advantages Over Spherical Lenses

Aspherical lenses are built to be cheaper and smaller than conventional lenses, and they often surpass the quality of lenses made from a spherical shape. Thanks to their manufacturing process, aspherical lenses are in continual improvement as technology moves forward.

References

• Opticampus: Ophthalmic Lens Design
• Nikon: Precision Glass Mold (PGM) Aspherical Lenses

Resources

• Nikon: Photography Glossary