Abstract: The invention relates to a device for measuring scattered light, comprising at least one focusing element provided with electromagnetic radiation that can be focused on a sample, a detector and a detector optical system with which electromagnetic radiation scattered by the sample can be conducted to the detector. The device is characterized in that it comprises means for forming an annular beam such that said annular beam can be focused on a focus point inside the sample by the at least one focusing element and that electromagnetic radiation scattered by the sample can be detected by the detection optical system, said electromagnetic radiation dispersing inside the area surrounded by the annular beam.