Cataract ultrasonic emulsion aspiration + IOL implantation has become the preferred procedure for cataract surgery, with the following advantages: incision less than 6mm, even up to 1.8mm; fast healing; small astigmatism; short operation time. It is very popular among patients. The size of the incision and the choice of IOL are closely related to cataract ultrasonic emulsion aspiration + IOL implantation. The general incision of ordinary rigid lens requires 6mm incision to implant the IOL into the eye, while the folded IOL requires only 3mm or smaller incision to implant the IOL into the eye, thus the surgical damage is smaller, the postoperative reaction is smaller and the recovery is faster. In recent years, IOLs have been developed rapidly. Patients with corneal astigmatism can choose crystals with astigmatism to obtain better naked eye vision and no longer need to wear glasses to correct astigmatism; patients who often read books or newspapers and need to see things at close range can choose multifocal IOLs or adjustable IOLs to solve the problem of seeing close without wearing presbyopic glasses. problem. Since IOLs cannot yet achieve the perfect function of our own crystals, some patients need to wear a certain number of degrees of eyes after surgery to obtain clearer vision.