8. Magneto-optical displays and printing systems

Bismuth ion-substituted ferrimagnetic garnets, BiYIG, with very high Faraday rotations and factors of merit in the visible range, have enabled direct visualization of a stored magnetic pattern and memory components for display systems. The operating principle of these devices is shown in figure 17 . The information to be visualized corresponds in the magneto-optical layer to a magnetic domain (or set of domains) of a given polarity perpendicular to the plane of the layer, with the rest of the layer magnetized in the other direction. When linearly polarized light passes through the garnet, the polarization direction of the beams corresponding to the information and the rest of the layer (the background) rotate in opposite directions. If the analyzer is set to block the light corresponding...