US Patent 7299482 High precision positioning apparatus

There is disclosed a high precision positioning apparatus capable of realizing accurate positioning of a recording medium with respect to an optical system by minute movement at a relatively low cost. The high precision positioning apparatus comprises a driving unit 1 for minutely moving a flat-plate shaped recording medium 10, which records/reproduces information using light, with respect to an optical system in an in-plane direction of the recording medium 10. The driving unit 1 comprises a frame-shaped unit body 2, a first drive frame 3 accommodated inside the unit body 2, and a second drive frame 4 accommodated inside the first drive frame 3 and fixed in the vicinity of a recording portion 11 of the recording medium 10. The first drive frame 3 freely moves with respect to the unit body 2 by means of micro-driving elements 5 in an in-plane direction of the recording medium 10, and the second drive frame 4 freely moves with respect to the first drive frame 3 by means of micro-driving elements 5 in an in-plane direction of the recording medium 10, in a direction substantially perpendicular to the direction in which the first drive frame 3 moves. Therefore, the recording medium 10 is minutely moved in an in-plane direction thereof.