Université de Neuchâtel

Micro-optical elements with arbitrary surfaces

Schilling, Andreas ; Nussbaum, Philippe ; Philipoussis, Irene ; Herzig, Hans-Peter ; Rossi, Markus ; Kley, Ernst-Bernhard

In: Diffractive Optics and Micro-Optics (DOMO), 2000, p. 234-236

We present a comparison of three different technologies for the fabrication of micro-optical elements with arbitrary surfaces. We used direct laser writing, binary mask lithography incombination with reactive ion etching, and graytone lithography.

Université de Neuchâtel

Optimized staircase profiles for diffractive optical devices made from absorbing materials

Nöhammer, Bernd ; David, Christian ; Gobrecht, Jens ; Herzig, Hans-Peter

In: Optics Letters, 2003, vol. 28, no. 13, p. 1087-1089

We report on the optimization of staircase grating profiles for the case of absorbing grating materials. Using a simple numerical algorithm, we determined the grating parameters, maximizing the first-order diffraction efficiency for different numbers of staircase steps. The results show that there is a significant difference between the staircase profiles for nonnegligible and negligible...

Université de Neuchâtel

Efficient Beam Shaping of Linear, High-Power Diode Lasers by Use of Micro-Optics

Schilling, Andreas ; Herzig, Hans-Peter ; Stauffer, Laurent ; Vokinger, Urs ; Rossi, Markus

In: Applied Optics, 2001, vol. 40, no. 32, p. 5852-5859

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 (DOEs) in combination with conventional optics. With a first prototype, we achieved an overall efficiency of 28%. Straightforward...

Université de Neuchâtel

Phase function encoding of diffractive structures

Schilling, Andreas ; Herzig, Hans-Peter

In: Applied Optics, 2000, vol. 39, no. 29, p. 5273-5279

We analyzed the direct sampling (DS) method for diffractive lens encoding, using exact electromagnetic diffraction theory. In addition to previously published research [Pure Appl. Opt. 7, 565 (1998)] we present what we believe to be new results for TM polarization. We found that the validity of the scalar-based DS method is even more extended for TM than for TE polarization. Additionally, we...

Université de Neuchâtel

Continuous-relief fan-out elements with optimized fabrication tolerances

Ehbets, Peter ; Rossi, Markus ; Herzig, Hans-Peter

In: Optical Engineering, 1995, vol. 34, no. 12, p. 3456-3464

The design of kinoform fan-out elements with high efficiency and reduced sensitivity to vertical profile scaling errors is presented. We start from a high-efficiency continuous-phase fan-out solution and optimize the position of the 0-2π transitions in the phase function, in order to achieve a high fabrication-error tolerance. The sensitivity of Fourier-transform and focusing fan-out elements to...

Université de Neuchâtel

Fabrication technologies for micro-optical elements with arbitrary surfaces

Schilling, Andreas ; Nussbaum, Philippe ; Philipoussis, Irene ; Herzig, Hans-Peter ; Stauffer, Laurent ; Rossi, Markus ; Kley, Ernst-Bernhard

In: Micromachining Technology for Micro-Optics (Proceedings of SPIE), 2000, vol. 4179, p. 65-72

We present a comparison of three different technologies for the fabrication of micro-optical elements with arbitrary surfaces. We used direct laser writing in photoresist, binary mask lithography in combination with reactive ion etching in fused silica, and High-Energy- Beam-Sensitive (HEBS) glass graytone lithography in photoresist. We analyzed the efficiencies and the deflection angles of...