What is Light? - Lenses

Single Lens Reflex (SLR) Camera Lenses that Use Laminated Diffractive Optical Elements

Chromatic aberration caused by diffraction on the one hand, and refraction on the other arise in completely opposite ways. Skillful exploitation of this fact enables the creation of small and light telephoto lenses.

Unlike pickup lenses for CD and DVD players, incorporating simple diffractive optical elements into SLR camera lenses results in the generation of stray light. However this problem can be resolved by using laminated diffractive optical elements, in which two diffractive optical elements are aligned within a precision of a few microns. If this arrangement is then combined with a refractive convex lens, chromatic aberration can be corrected. Smaller and lighter than the purely refractive lenses that have been commonly used until now, these diffractive lenses are now being increasingly used by sports and news photographers.