Inclusion Criteria:  The patients are diagnosed age related cataract with axial length over 26mm The patients' age over 50 years old The patients plan to receive cataract surgery in Eye hospital of Wenzhou Medical University The dialated pupils are over 6mm Patients are willing and able to complete the follow-ups.  Exclusion Criteria:  Patients with other type of cataract Patients have complications in the surgery and after surgery Patients have other severe diseases of eyes