Advantages Of Using Plastic Hybrid Aspheric Lenses

TECHSPEC® Plastic Hybrid Aspheric Lenses are low cost optical components that lack both spherical and chromatic aberrations. These aspheric lenses provide optical designers with unique, single element solutions for achieving diffraction-limited focusing performance at high numerical apertures with broadband light sources. These aspheric lenses consist of a diffractive surface that has been added to a molded aspheric lens. The aspheric lens eliminates all spherical aberration, while the diffractive surface has a net effect of introducing negative dispersion – when properly tuned to the refractive index and wavelength design of the lens, chromatic aberration is eliminated as well.

SPHERICAL AND CHROMATIC ABERRATIONS
There are two major forms of axial optical aberrations inherent in common optical lenses: spherical aberration and chromatic aberration. Spherical aberration is an inherent characteristic of any lens whose surface is a section of a sphere. Light originating from the same object point comes to a focus at slightly different points (P and P’), depending on whether the rays pass through the center of the lens or the periphery.

Chromatic aberration results from material dispersion. Because different colors of light refract by different amounts, an image point formed by light of one color does not coincide with the corresponding image point formed by light of a different color.