Testing the vision of cataract patients by means of laser-generated interference fringes

In a new technique for measuring the visual acuity of cataract patients the light from a laser is used to form interference patterns of variable fineness on the patient's retina. The fineness of the interference pattern that the patient can detect gives an indication of the potential for improved vision. Comparison of this estimate of the potential with the patient's vision after cataract extraction shows that this test can indicate the condition of the fovea behind a cataract.