Abstract: A high power optical combiner (18) is provided for amplifying an optical signal. The combiner (18) includes a splitter (20) having a splitter input (22)and two splitter outputs (24, 26). The splitter input (22) receives an optical signal which the splitter divides (20) into two sub-signals. The splitter outputs (24, 26) have respectively coupled thereto a reference arm (30) and a dither arm (32). Both arms (30, 32) receive the sub-signals from the respective splitter outputs (24, 26) and transmit the sub-signals in parallel. Each arm (30, 32) has an amplifier (34) integrated therein for amplifying the sub-signals in parallel thereby producing amplified sub-signals. The high power optical combiner (18) further includes a combining coupler (42) connected to both arms (30, 32). The combining coupler (42) has two coupler inputs (46, 48), and a coupler output (50). The coupler inputs (46, 48) receive the amplified sub-signals from the arms (30, 32).