Abstract: The invention relates to an illumination device, in particular for a confocal microscope. The object of the invention is to provide an illumination device which operates with a plurality of current-modulated semiconductor-based light sources, in which the light emission is as free as possible from distortions due to dynamic delays of the light emission in the output beam.

Abstract: The invention relates to a method for modulating the resonant frequency of an optical resonator (1) in accordance with a periodic, not necessarily harmonic, modulation signal (Umod(t)). Fast modulation of an optical resonator is intended to be made possible in which the current resonant frequency follows the modulation signal (Umod(t)) as precisely as possible, and specifically at a fundamental frequency of the modulation signal in the kHz range. To do this, the invention proposes the following method steps: deriving an error signal (E(t)) from a light field circulating in the resonator (1), wherein the error signal (E(t)) indicates the deviation of the optical frequency of the light field from a target value, deriving a first actuating signal (S1(t)) from the error signal (E(t)) by means of a controller (6), generating a second actuating signal (S2(t)), which has actuating-signal components at one or more harmonics (fmod, 2fmod, . . .

Abstract: The invention relates to an illumination device, in particular for a confocal microscope. The object of the invention is to provide an illumination device which operates with a plurality of current-modulated semiconductor-based light sources, in which the light emission is as free as possible from distortions due to dynamic delays of the light emission in the output beam.

Abstract: The invention relates to a method for modulating the resonant frequency of an optical resonator (1) in accordance with a periodic, not necessarily harmonic, modulation signal (Umod(t)). Fast modulation of an optical resonator is intended to be made possible in which the current resonant frequency follows the modulation signal (Umod(t)) as precisely as possible, and specifically at a fundamental frequency of the modulation signal in the kHz range. To do this, the invention proposes the following method steps: deriving an error signal (E(t)) from a light field circulating in the resonator (1), wherein the error signal (E(t)) indicates the deviation of the optical frequency of the light field from a target value, deriving a first actuating signal (S1(t)) from the error signal (E(t)) by means of a controller (6), generating a second actuating signal (S2(t)), which has actuating-signal components at one or more harmonics (fmod, 2fmod, . . .