A measuring device for determining the loading and the vibrations of a washer drum of a washing machine, comprising: a first light emitter configured to emit light of a first wavelength λ1; a second light emitter configured to emit light of a second wavelength λ2, wherein particularly the second wavelength λ2 differs from the first wavelength λ1; a reflector to be illuminated by the first and the second light emitters (102, 103) and configured to at least partially reflect the light having the first wavelength λ1 and the light having the second wavelength λ2, the reflector comprising a plurality of reflection zones (201A - 201D) having different reflection rates; a light receiver configured to measure the intensity of the light being reflected by the reflector, wherein the measured intensity depends on the reflection zone, such that a variation of the measured intensity of the received light between an initial state, particularly unloaded state of the washer drum, and a working state, particularly loaded state of the washer drum, is caused by a first relative displacement of the reflector with regard to the first and second light emitters (102, 103) and the light receiver, and that a difference between the received light intensity of the wavelength λ1 and the received light intensity of the wavelength λ2 between the initial and the working state is caused by a different second relative displacement of the reflector with regard to the first light emitter and the second light emitter; and a processor configured to determine the loading of the washer drum based on the first relative displacement and for determining the vibrations of the washer drum based on the second relative displacement. a first light emitter configured to emit light of a first wavelength λ1; a second light emitter configured to emit light of a second wavelength λ2, wherein particularly the second wavelength λ2 differs from the first wavelength λ1; a reflector to be illuminated by the first and the second light emitters (102, 103) and configured to at least partially reflect the light having the first wavelength λ1 and the light having the second wavelength λ2, the reflector comprising a plurality of reflection zones (201A - 201D) having different reflection rates; a light receiver configured to measure the intensity of the light being reflected by the reflector, wherein the measured intensity depends on the reflection zone, such that a variation of the measured intensity of the received light between an initial state, particularly unloaded state of the washer drum, and a working state, particularly loaded state of the washer drum, is caused by a first relative displacement of the reflector with regard to the first and second light emitters (102, 103) and the light receiver, and that a difference between the received light intensity of the wavelength λ1 and the received light intensity of the wavelength λ2 between the initial and the working state is caused by a different second relative displacement of the reflector with regard to the first light emitter and the second light emitter; and a processor configured to determine the loading of the washer drum based on the first relative displacement and for determining the vibrations of the washer drum based on the second relative displacement.