An apparatus for frequency comb generation comprises a component of second order nonlinearity, where the component is configured to interact with a laser beam or derivatives of the laser beam and thereby generate frequencies for the frequency comb. The apparatus comprises advantageously an optical manipulator, which both comprises the component but additionally is configured to introduce the beam or its derivatives in a repetitive or resonating manner to the component. The component is e.g. a monolithic or other solid optical resonator or microresonator comprising optical crystal and having said second order nonlinearity.