An instrument for measuring and analyzing surface plasmon resonance on a sensor surface has a polarized light source optically connected to the sensor surface by a plurality of optical elements, including in one embodiment an optical telescope that transfers light from a rotatable reflecting surface to the sensor surface. Selective positioning of a cylindrical lens into a first position within the path of light transforms collimated light to a rectangular wedge that is incident upon the sensor surface at numerous angles. In another embodiment, the light source is operated as a laser to excite fluorescence on the sensor surface and the fluorescence is selectively directed to a detector by appropriate optical elements positioned in specific configurations.