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AssigneeDeutsch Forschungs- und Versuchsanstalt fur Luft- und Raumfahrt e. V.
InventorsRolf Gauert, Werner W. Jungbluth
Estimating the term…
A ring laser having at least three corner mirrors, of which one carries a ferromagnetic garnet layer on a substrate and is coated with a plurality of interference layers and magnetized at right angles to the ferromagnetic garnet layer. The ring laser is designed in such a way that the corner mirror which carries the ferromagnetic garnet layer acts in reflection as a Faraday cell and, in particular, in that the ferromagnetic garnet layer is subjected to circularly polarized radiation. The circularly polarized radiation may be produced by arranging in front of the corner mirror which carries the ferromagnetic garnet layer a .lambda./4 retarding plate. Another possibility consists in providing those corner mirrors which in the radiation path are adjacent to the corner mirror which carries the ferromagnetic garnet layer with a plurality of interference layers which are arranged in such a way that circularly polarized radiation is converted into linearly polarized radiation by means of a 90.degree. phase shift and vice versa.
A ring laser having at least three corner mirrors of which one requires circularly polarised light to be incident thereon, said one corner mirror including a substrate having a ferromagnetic garnet layer thereon, the garnet layer being magnetised to saturation in a direction perpendicular to that layer, and a plurality of superimposed highly reflecting interference layers on the surface of the garnet layer facing the incident circularly polarised light, the interference layers having a reflectivity of approximately 99.4% and permitting approximately 0.6% of the incident light to pass through into the garnet layer, the passed small fraction of the light being sufficient to enable the desired bias or phase shift to be achieved.
Dependencies are inferred from the claim text.