A combination device includes at least two inputs and one or more outputs. Each input is for entry of a respective input beam. Each output is for exit of a respective output beam. The combination device is configured to form the respective output beam through a coherent combination of two input beams. The combination device is configured to set a polarization direction of the respective output beam based on a relative phase position of individual phases of the two input beams from which the respective output beam is formed through the coherent combination.