Time delay in one dimension with two and three microlenses. The microlenses are at positions A, B, and C. The dashed lines show the time delay when only one of the three microlenses is considered. The solid lines corresponds to the time delay when two or three microlenses are considered. Microimages form around the positions where the derivative of the time delay equals zero. The magnification of each microimage is inversely proportional to the curvature (i.e., second derivatives) of the time delay around these positions.