The present invention relates to a method for investigating a sample using scanning probe photon microscopy or optical force microscopy, and to an apparatus which is designed accordingly. The method or the apparatus provides for two optical traps which can be moved in a local region of the sample, wherein in at least one of the two traps a probe is held. The sample is scanned using the two traps and the measured data from the two traps are captured separately and evaluated by correlation. In particular interference signals resulting from an interaction between sample and light trap can be eliminated by the method.