Abstract: Arrangement for analysis of substances at or near the surface of an optical sensor with at least one wave-guiding film and at least one multidiffraction grating coupler for in-coupling and out-coupling of light beams, in which at least two light beams enclosing an angle .alpha. relative to one another are coupled in and by which at least two light beams enclosing an angle .phi. relative to one another are coupled out, and with a detection system for detecting the out-coupled light beams, wherein in-coupling and out-coupling are effected on one and the same side of the sensor and the in-couple beams and out-couple beams lie in different quadrants of the plane of incident light, and the angle .alpha. between the in-couple beams is greater than the angle .phi. between the out-couple beams. The arrangement has multiple uses for determining physical or chemical measured quantities based on the interaction of the guided light waves with the medium at or near the sensor surface.