Clinical research has demonstrated the the continuous decline of the contrast sensitivity with age results from increasing spherical aberration of the human crystalline lens. Replacing the crystalline lens with appropriate modeled pseudophakic lens can provide superior contrast sensitivity and functional vision. As advances in the technology allow cataract and refractive surgeons to address higher-order optical aberrations, the measurement of functional vision becomes increasingly critical as a gauge of the progress. Contrast sensitivity testing is assuming a prominent place in the evaluation of surgical modalities because it reflects functional vision, correlates with visual performance, and provide a key to understanding optical and visual processing of images.