Abstract: A high resolution observation apparatus of material features with a photon scanning microscope. The apparatus detects evanescent light which depends on surface feature of a sample and detects detailed distribution of optical constants of the sample. Namely, the apparatus makes it possible to detect detailed distribution of transparency or refractive index within a sample material in higher resolution than the wavelength of the incident light which is irradiates to the sample material coated on the top surface of the optical prism. The apparatus includes means for maintaining a predetermined distance between the sample and an optical fiber tip or means for detecting a positioning signal. Further, it becomes possible to detect fluorescent condition of the sample.