Patent ID: 7299482

Claim:
A high precision positioning apparatus having a driving unit for minutely moving a flat-plate shaped recording medium, which records/reproduces information using light, with respect to an optical system in an in-plane direction of the recording medium, a recording portion of the recording medium being positioned in a predetermined position by the driving unit, wherein the driving unit comprises a frame-shaped unit body, a first drive frame accommodated inside the unit body, and a second drive frame accommodated inside the first drive frame and fixed in the vicinity of the recording portion of the recording medium, and wherein the first drive frame freely moves with respect to the unit body by means of micro-driving elements in an in-plane direction of the recording medium, and the second drive frame freely moves with respect to the first drive frame by means of micro-driving elements in an in-plane direction of the recording medium, in a direction substantially perpendicular to the direction in which the first drive frame moves, so that the recording medium is minutely moved in an in-plane direction of the recording medium by moving the first drive frame and the second drive frame with respect to each other, and wherein the second drive frame includes air holes disposed substantially perpendicular to the recording medium and the second drive frame is fixed to or isolated from the recording medium by air aspirated or ejected through the air holes.