EN
The present paper deals with investigations concerning optical magnetic sensors. The most important advantage of sensors of this kind is their safety of service and insulating power. The insensitiveness of optical sensors to electromagnetic interference was discussed and experimentally investigated. The experimental investigations were concentrated on the adequate sensing fibre as well as on the sensor based on the bulk glass cylinder. The paper presents the results of magnetooptic tests of the elaborated magnetic field optical sensors and conclusions arise from them.