Birefringence measurement optical system and high spatial resolution polarimetric apparatus

The object of the present invention is to measure the amount of birefringence of a target while enhancing spatial resolution. A birefringence measurement optical system is comprised of a Stabilized Transverse Zeeman Laser emitting laser beam in a predetermined polarization state toward a target, a halfwave plate (polarized light emission optical system), a linear polarizer (polarized light detection optical system) detecting information on the retardation, main axial direction and optical rotation angle of the target as a light signal which can be polarimetrically analyzed through the target, and a photo detector converting the light signal from the linear polarizer into an electric signal and detecting the electric signal. An optical fiber (light transmission path) taking out part of light fluxes of the light signal and optically transmitting the part of the light fluxes from the target toward the photo detector, is arranged between the photo detector and the target.