Light source consisting of several successively connected leds

The invention relates to a light source, consisting of a number of LEDs (2) which are successively connected one behind the other and which are connected in series to a series resistance (4). The invention is characterised in that (a) the electric circuit of the LEDs (2) has, in addition to the series resistance (4), a rapid electronic switch (6) and a rectifier circuit (8) as the power source which, when in operation, is connected to the voltage of the public mains supply; (b) the rapid electronic switch (6) is connected to a pulse generator (10) which provides pulses with a repetition frequency of at least 70 Hz; (c) the series resistance (4) is smaller than a protective resistor which operates with a constant current (d) the arrangement is configured in such a way that the amplitude of the current to the LEDs (2) is greater than the maximum current which is permitted with a constant current.