a cemented lens comprising a first component having a polished first surface , a second component whose refractive index is different from that of the first component and having a second surface smoothed to a finish roughness of mesh # 1400 or more but not polished , and an adhesive agent layer intervening between the first and second components to cement them at the first and second surfaces and having a refractive index which does not differ from that of the second component by more than 0 . 1 .