Abstract: An optical coupling element having a convex, refractive microlens is characterized by a ball having a flat, planar surface being mounted in a through-hole of a carrier lamina with the flat, planar surface extending parallel to a planar surface of the lamina. The coupling element is preferably made by a method which involves forming a through-hole in a lamina, mounting a ball in the through-hole, processing a surface of the ball to form the planar surface that extends parallel to a surface of the lamina. Preferably, a plurality of coupling elements are formed by providing a plurality of through-holes in an enlarged carrier and after processing, each individual coupling element is then separated from this enlarged carrier.

Abstract: An arrangement for converting diverging polarized laser emission from a semiconductor laser into a convergent beam includes two optical lenses and an optical isolator formed of a Faraday rotator and at least one polarizer arranged in the beam path of the laser emission. The lens which lies farther from the semiconductor layer is a component of the Faraday rotator and is formed by a plano-convex lens having an curved side facing the semiconductor laser.

Abstract: A transmission and reception module for a bidirectional optical communication network characterized by a housing containing a laser diode, a first spherical lens for focussing the output of the laser diode on a first beam path, a second spherical lens arranged on the first beam path for focussing the light from the first lens at a focal point at which an end face of an optical fiber is positioned, a beam splitter which is at least partially transmissive to light of a first wavelength from the laser diode and partially reflective of light of a second wavelength being emitted from the fiber into a second beam path on which a detector is positioned. To improve the positioning, the first lens and the laser diode are mounted on a carrier member in a fixed relationship which enables assembling the device with less problems with maladjustment.

Abstract: The invention concerns a firing device for a number of electric valves, particularly thyristors. Each thyristor control path is associated with a firing circuit with a detector for electromagnetic radiation responsive to a transmitter which is controlled by a firing control signal and is equipped with a radiating device which energizes the individual detectors. To transmit the firing control signal with sufficient strength, a transmitter with a radiator is provided which is arranged in the focal line of a reflector designed as a partial elliptical cylinder. The individual detectors are disposed in a line which is aligned essentially parallel to the focal line of the reflector.

Abstract: The invention concerns a circuit arrangement for the wireless transmission of control signals to the control paths of controlled semiconductor valves, particularly of thyristors, which are preferably usable in a rectifier for high voltage. The control signals are provided for the modulation of a high-frequency transmitter which is disposed at some distance from high frequency receivers each containing a demodulator, whose output signal is delivered to the control path of a semiconductor valve. In order to ensure reliable and interference-proof firing of the semiconductor valves, if the distance between the high-frequency transmitter and the high-frequency receiver is large, there is provided, a frequency-modulated high-frequency transmitter as the high-frequency transmitter.