Apochromatic color correction using liquid lenses.

A new method of attaining apochromatic color correction in refractive optical systems has been developed. Common, low-cost optical glasses and abnormal dispersion optical liquids are combined to produce optical systems that have a degree of color correction which previously was possible only by using abnormal dispersion glasses or crystals. In addition to providing dramatic color correction these liquids have good availability, reasonable cost, and low light scatter. Two designs are presented: a glass-liquid apochromatic telescope objective which uses one abnormal dispersion liquid, and an athermal design which uses two liquids. Also presented are the theoretical and experimentally measured optical performance characteristics of these two lenses.