LASER BEAM-COMBINING OPTICAL DEVICE

The present invention provides a laser beam-combining optical device capable of combining laser light beams from a plurality of lasers with a simple configuration. The laser beam-combining optical device (100) according to the present invention includes a plurality of semiconductor laser arrays (10a, 10b, 10c), and a reflective element (11b, 11c) that reflects a laser light beam emitted from at least one semiconductor laser array (10b, 10c) of the plurality of semiconductor laser arrays (10a, 10b, 10c). When laser light beams emitted from respective ones of the plurality of semiconductor laser arrays (10a, 10b, 10c) are focused on a single focus point (14), the laser light beam emitted from the at least one semiconductor laser array (10b, 10c) is reflected by the reflective element (11b, 11c), and is then focused on the focus point (14).