By chiseling a BOL on a surface of a lens, a apochromatic system is composed, which actualizes the system's apochromatism, as well as revising primary aberration.

并将二元光学面透镜的表面，校正系统初像差的同时，实现了系统的差。

Apochromatic lens: Compound lens corrected for chromatic aberration, i.e. the three primary colours , red, green and blue are corrected. Also called Apochromat.

矫正差的合式透镜：即是红、绿和蓝三原的差都已矫正。