Two-dimensional position control method and two-dimensional position control apparatus

摘要

There is provided a two-dimensional position control method which carries out two-dimensional position control fast at a minimum wobbling frequency. The method includes a step of oscillating at least either a space propagation energy distributed in a substantially limited range on a predetermined two-dimensional plane or energy input system to which the energy is input such that a locus of a relative movement thereof forms an ellipse on the two-dimensional plane, a step of detecting energies at least two pairs of points on the elliptic locus on both sides of the center of the ellipse, and a step of calculating differences between the detected energies at the respective pairs of points, thereby detecting a displacement between the energy and the energy input system on the two-dimensional plane.