Abstract: A laser distance ranging method includes splitting two combs of dual comb radiation into a signal radiation portion and a local oscillator radiation portion. The signal radiation portions are, after separation, combined into a combined signal radiation and directed onto an object, the distance to which is to be measured. The signal thrown back from the object is split into a first and second signal portions. The first signal portion is superimposed with the second local oscillator radiation portion to generate a first measurement signal, and the second signal portion is superimposed with the first local oscillator radiation portion to generate a second measurement signal. The distance to the object is determined from the first and second measurement signals, and from reference signals obtained by the partial reflection, wherein the Vernier effect can be used to extend ambiguity by comparison of the first and second measurement signals.

Abstract: An apparatus for emitting electromagnetic radiation includes a gain element, an optical arrangement defining a resonator and arranged to re-direct radiation emitted by the gain element along a beam path back onto the gain element, the optical arrangement including an output coupler configured to couple a portion of the radiation in the resonator out of the resonator, and a pump arrangement configured to pump the gain element. The optical arrangement further includes a passive device placed in the resonator in the beam path, the passive device having at least two surface portions at an angle to each other. The passive device is arranged to direct first radiation portions and second radiation portions of the radiation, which first and second radiation portions are incident on different ones of the surface portions, to be spatially separated. The apparatus is suitable as a source of dual-comb pulsed laser radiation.