Abstract: In a laser block (10) spokes (26,28,30) and a hub (34) are mechanically worked out resulting in a monolithic integration of a dither device into the laser block.

Abstract: A sensor of rotational velocity on the basis of a ring laser having an external radiation path including one corner mirror of the active resonance space which is transparent to the radiation of the active resonance space and at least two corner mirrors in the external radiation path between which there is arranged a magnetically excited body consisting of a material with a magnetooptical effect to act as a bias element for the production of a phase shift. The corner mirror of the active resonance space which leads to the external radiation path has a transparency of at maximum 5% and the magnetically excited body consists of a material which can be magnetized to saturation. The body is, preferably, a Faraday cell which is constructed from a ferromagnetic compound, in particular a garnet compound.

Abstract: 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.