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 indifferent 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, and wherein the light emitting diodes are positioned on said plate so that there is a certain distance between two adjacent light emitting diodes. The invention is characterised in that the drive device (9,10)is arranged to control the light emitting means to emit pulsating light with a pulse length which lies within an interval of about 60% to 90% of the time between the respective start edge of two consecutive pulses, and is arranged to vary the length of the pulses over time.
