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Université de Neuchâtel

Encoding of efficient diffractive microlenses

Kuittinen, Markku ; Herzig, Hans-Peter

In: Optics Letters, 1995, vol. 20, no. 21, p. 2156-2158

Different coding schemes for diffractive multilevel microlenses are compared. A simple method to code a lens to get the optimum diffraction efficiency is given. Furthermore, a straight forward way to estimate the achievable efficiency of a lens is presented.

Université de Neuchâtel

High-efficiency continuous surface-relief gratings for two-dimensional array generation

Ehbets, Peter ; Herzig, Hans-Peter ; Prongué, Damien ; Gale, M. T.

In: Optics Letters, 1992, vol. 17, no. 13, p. 908-910

Continuous surface-relief phase for two-dimensional (2-D) array generation have been realized by laser-beam writing lithography. For a 9 x 9 fan-out element, a diffraction efficiency of 94% and a uniformity of better than 8% have been achieved. These are, to our knowledge, the best published results for 2-D surface-relief fan-out elements. Separable and nonseparable solutions for the design of...

Université de Neuchâtel

Diffraction from metallic gratings with locally varying profile forms

Tompkin Wayne R. ; Staub, René ; Schilling, Andreas ; Herzig, Hans-Peter

In: Optics Letters, 1999, vol. 24, no. 2, p. 71-73

Measurements of the diffraction characteristics of one-dimensional surface-relief gratings of locally varying profile are compared with rigorous diffraction theory. These gratings result from the superposition of two linear sinusoidal gratings of uniform depth for which the relative phase between the two gratings varies slowly with position. The resultant surface profile exhibits a relatively...

Université de Neuchâtel

Miniaturized time-scanning Fourier transform spectrometer based on silicon technology

Manzardo, Omar ; Marxer, Cornel R. ; de Rooij, Nicolaas F. ; Herzig, Hans-Peter

In: Optics Letters, 1999, vol. 24, no. 23, p. 1705-1707

We present a miniaturized Fourier transform spectrometer (FTS) based on optical microelectromechanical system technology. The FTS is a Michelson interferometer with one scanning mirror. A new type of electrostatic comb drive actuator moves the mirror. We have measured a nonlinearity of the driving system of ±0.5 μm for a displacement of 38.5 μm . A method is presented to correct...

Université de Neuchâtel

Quantitative amplitude and phase measurement by use of a heterodyne scanning near-field optical microscope

Nesci, Antonello ; Dändliker, René ; Herzig, Hans-Peter

In: Optics Letters, 2001, vol. 26, no. 4, p. 208-210

A coherent photon scanning tunneling microscope is presented. The setup employs heterodyne interferometry, allowing both the phase and the amplitude of the optical near field to be measured. Experimental results of measurements on a standing evanescent wave reveal the high resolution that is obtainable with such an approach. In fact we have measured the amplitude and the phase of the near field,...

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

Wavelength-dependent optical force on elliptical silver cylinders at plasmon resonance

Rockstuhl, Carsten ; Herzig, Hans-Peter

In: Optics Letters, 2004, vol. 29, no. 18, p. 2181-2183

We use rigorous diffraction theory to analyze the force on elliptical cylinders made from silver as a function of the elongation. We find that, when the wires are illuminated at the plasmon wavelength and placed in a highly focused Gaussian beam, they are attracted toward the optical axis if the waist of the laser is behind the wire and repelled if the waist is before the wire. Also, the force...

Université de Neuchâtel

Miniature lamellar grating interferometer based on silicon technology

Manzardo, Omar ; Michaely, Roland ; Schädelin, Felix ; Noell, Wilfried ; Overstolz, Thomas ; de Rooij, Nicolaas F. ; Herzig, Hans-Peter

In: Optics Letters, 2004, vol. 29, no. 13, p. 1437-1439

We present a lamellar grating interferometer realized with microelectromechanical system technology. It is used as a time-scanning Fourier-transform spectrometer. The motion is carried out by an electrostatic comb drive actuator fabricated by silicon micromachining, particularly by silicon-on-insulator technology. For the first time to our knowledge, we measure the spectrum of an extended...