We have designed, fabricated, and characterized a micro-optical beam-shaping device that is intended to optimize the coupling of an incoherent, linearly extended high-power diode laser into a multimode fiber. The device uses two aligned diffractive optical elements ͑DOEs͒ in combination with conventional optics. With a first prototype, we achieved an overall efficiency of 28%. Straightforward improvements, such as antireflective coatings and the use of gray-tone elements, are expected to lead to an efficiency of approximately 50%. The device is compact, and its fabrication is suited for mass production at low cost. This micro-optical device, used in a range-finder measurement system, will extend the measurement range. In addition to the direct laser writing technique, which was used for fabrication of the DOEs of the prototype, we applied two other technologies for the fabrication of the micro-optical elements and compared their performance. The technologies were multiple-projection photolithography in combination with reactive-ion etching in fused silica and high-energy beam-sensitive glass gray-tone lithography in photoresist. We found that refractive-type elements ͑gray tone͒ yield better efficiency for large deflection angles, whereas diffractive elements ͑multilevel or laser written͒ give intrinsically accurate deflection angles.

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We designed, fabricated and characterized a micro-optical beamshaping device, intended to optimize the coupling of an incoherent, linearly extended high-power diode-laser into a multimode fiber. The device uses two aligned micro-optical elements (DOEs) in combination with conventional optics. With a first prototype we achieved an overall efficiency of 28 %. Straightforward improvements, like antireflective coatings and the use of graytone elements, should lead to an efficiency of about 50 %. The device is compact and the fabrication is suited for mass production at low cost. We applied three different technologies for the fabrication of the micro-optical elements and compared the performance. The technologies were: direct laser writing, multiple projection photolithography in combination with reactive ion etching (RIE) in fused silica, and highenergy-beam-sensitive (HEBS) glass graytone lithography in photoresist. We found that the refractive type elements (graytone) yield better efficiency for large deflection angles, while diffractive elements give intrinsically accurate deflection angles.