Abstract: An optical fiber sensor has a sensor band of optical sensor fibers. The band is connected on both ends to a transmitter unit and a receiver unit, the transmitter unit feeding optical signals into the optical fibers, the signals being optically evaluated with regard to the intensity thereof by the receiver unit. Parallel electrical conductors are located in the sensor band and can, for example, be designed as ribbon cables. The electrical conductors allow an additional electrical connection of the transmitter unit and the receiver unit, so that external cables advantageously need only be connected to one of the two units. The difficulty of connection is thereby reduced, and the wearing comfort is increased for the application of the fiber sensor, for example, as a back sensor.