Abstract: The synthetic antiferromagnet disk-shaped particle comprises a first ferromagnetic layer, a second ferromagnetic layer and a non-magnetic interlayer arranged between the first and the second ferromagnetic layer, wherein each of the first and the second ferromagnetic layer comprises a uniaxial magnetic anisotropy in the plane of the ferromagnetic layers such that the switching fields from an antiferromagnetic alignment of the first and the second ferromagnetic layer to a ferromagnetic alignment (HAF?F) and from the ferromagnetic alignment to the antiferromagnetic alignment (HF?AF) fulfill the condition H AF ? F - H F ? AF > 1 4 · H AF ? F .

Abstract: A method for calibrating magnetic force microscopes (MFM) or scanning Hall probe microscopes (SHPM) is disclosed, wherein an instrument response function IRF is determined for correcting arbitrary raw MFM- or SHPM-images Si. According to one aspect of the invention a sample with an irregular magnetization pattern M over an extended area is provided, a raw MFM- or SHPM-image S is measured, an approximate sample magnetization pattern M0 and therefrom an approximate magnetic stray field distribution H0 are determined and an instrument response function IRF is calculated using the raw MFM- or SHPM-image S and the approximate magnetic stray field distribution H0. Other aspects of the calibration method consist in that the instrument response function IRF is calculated in Fourier space as IRF(k)=S(k)H0(k) and/or that averages or iterative calculations of instrument response functions IRFj (j=1 . . . m) are performed.

Abstract: Liquid cell crystal, with fine structures made up of regions having defined different orientation and dimensions of the order of 0.1 to about 100 &mgr;m can be used as optical conductors and projection displays. The fine structures in the liquid crystals are produced in that the plates bounding and guiding the liquid crystal are provided with micromechanically produced regions having different defined preferred directions. The result is a molecular orientation having a higher refractive index that the surrounding region for guiding and polarizing irradiated light. The orienting layers on the plates bounding the liquid crystal are micromechanically structured in that certain spatial regions are mechanically structured in a uniform direction by a stylus moved by piezoelectric means.