Laser diode array assemblies with optimized brightness conservation

Abstract

The invention relates to laser diode arrays having high beam quality and high beam brightness. In one approach, a laser diode array package includes a mount and first and second laser diode arrays disposed on the mount. Each of the laser diode arrays defines an optical axis and has an emitting surface lying in an emitting surface plane. The emitting surface plane of the first laser diode array is displaced relative to the emitting surface plane of the second laser diode array in a direction parallel to one of the optical axes. The optical axes of the first and second laser diode arrays are offset from each other in a direction perpendicular to one of the optical axes. First and second lenses are disposed relative to respective emitting surfaces to reduce divergence of light output from the emitting surfaces. In another approach, laser diode array bars are stacked and the individual output beam from each bar is collimated using a short focal length, low aberration lens. The resulting collimated beams are treated with reflectors to reduce, or remove, the dead spaces between adjacent collimated beams, thus permitting the use of low aberration lenses, which results in an improved divergence-size product for each beam produced by a bar. Additionally, the total beam output by the array of laser bars is condensed in size.