Inclusion Criteria:  Age-related cataracts performed by the same surgeon in our hospital; Pupil diameter can be enlarged more than 6 millimetre.  Exclusion Criteria:  The pupil diameter cannot be dilated greater than 6mm; previously ocular surgery or laser treatment; history of ocular trauma; other ocular diseases such as keratoconus, glaucoma and retinal detachment; corneal opacities caused by leucoma, pterygium and other diseases; lens dislocation or complicated cataract surgery (any complications during/after the operations); poor fixation leading to low image quality or inability to cooperate with examinations.