Device for external medical treatment using light, comprising a light emitting means (1) arranged to abut against or be held near the body of an individual as well as a drive device (9,10) for the light emitting means, which light emitting means comprises light emitting diodes or the corresponding (3,4), which light emitting diodes are arranged to emit light in different wavelength intervals, wherein the drive device (9,10) is arranged to control the light emitting means (1) to emit light of one or several wavelengths during one or sever- al predetermined times and to emit said light in a pulsating manner, which light emitting means comprises a cover and a light emitting diode plate (2), supporting the light emitting diodes, wherein the light emitting diodes are positioned on said plate so that there is a certain distance between two adjacent light emitting diodes, and wherein the device is arranged to emit light in two or several series with increas- ing pulse frequencies F1, F2, Fn, where F1 is a fundamental frequency and where F2 and Fn are multiples of the fundamen- tal frequency. The invention is characterised in that the device is arranged to emit a pulse repetition frequency that varies about the respective frequency F1, F2 and Fn.
