Higher-order aberration diagnosis

It is less known that nearsightedness, farsightedness and astigmatism all belong to lower-order aberrations. And there are also higher-order aberrations such as coma, spherical aberration and trefoil. Higher-order aberrations may cause symptoms such as poor night vision, glare, halos, blurring, starburst patterns, double vision and loss of visual contrast. In most cases, slight higher-order aberrations are common and safe.