A Detector System for Identifying Substances in a Sample

A system for identifying substances in a sample comprises an array of cantilevers (330), at least some of the cantilevers being provided with a recognition layer and adapted to bend if the recognition layer reacts with the substance, and a common-path interferometer for measuring cantilever bending, said interferometer comprising an array of light sources (312) for emitting spatially coherent light, a transmitter diffractive optical element (319) for splitting the light into a plurality of probing beam sets, each beam set comprising at least a first probing beam and a second probing beam for illuminating a first area and a second area of the corresponding cantilever (330); a detector array (334, 336), and a receiver diffractive optical element (329) adapted to collect light reflected from the cantilever array and to form at least two spatially overlapping images of said areas so that interference between the two spatially overlapping images is formed and measured by at least one separate detector (334, 336) of the detector array.