Abstract
Two clinical interferometers generated gratings directly on the retina in young experienced observers and also in patients about to undergo cataract surgery. Eyes in the patients with no media opacities were used as controls. Gratings were seen on the retina independent of refractive state. Gratings can still be seen through most cataracts. Preoperative retinal visual acuity was of no value in predicting postoperative Snellen visual acuity. Reasons for this are discussed.