Offset laser array with beam combining optical element

A laser beam device comprising:

• a laser array comprising several laser diodes arranged in a stepped form, each laser diode having an emitting surface;
• a shaping optical system, set at the emitting side of said laser array;
• a beam combining optical element, set at the emitting side of said shaping optical system, wherein said beam combining optical element comprises several reflecting surfaces corresponding to each of the laser diodes of said laser array, and said reflecting surfaces are arranged in a stepped form;
• wherein said several laser diodes include a first laser diode and a plurality of second laser diodes, said first laser diode positioned farther from the beam combining optical element than the second laser diodes;
• wherein the emitting optical path length from the emitting surface of the first laser diode to said beam combining optical element is substantially equal to the optical path length for each second laser diode, consisting of the sum of the emitting optical path length from the emitting surface of each second laser diode to its corresponding reflecting surface in said beam combining optical element and the reflecting optical path length from said corresponding reflecting surface to the emitting optical path from the first laser diode to said beam combining optical element.