An apertureless optical near-field scanning microscope system has been created by combining a commercially available atomic force microscope and an ellipsometer without any prior changes in design of the respective devices. In preliminary experiments, an optical resolution of about 20 nm ~l/32! has been achieved using the combined microscope. The intensity of the measured optical signal has been found to be a periodic function of the thickness of the sample. Moreover, the period of this function is dependent upon the local optical properties of the sample material. 組合式多功能橢偏儀