An optical apparatus for recording and / or reproducing

The optical recording and / or reproducing optically performs the recording operation and / or reproducing information on a data carrier 1 by directing a beam of an optical head 7 on a data carrier 1. in this apparatus, the angle between the optical axis 10 of the beam from the optical head 7 and the face of said data carrier 1 is detected and a temperature control device 17 provides a temperature difference between the two faces of the data carrier 1 on the basis of the detected result with respect to the angle, the temperature difference producing a thermal stress which acts to release the tension imposed beforehand the data carrier 1.