Abstract: A tunealble optical grid-assisted add/drop filter for codirectional operational mode consisting of at least two waveguides composed of two different classes of material of different optical parameters. The thermal refractive index coefficient dn/dT, the electro-optic coefficient dn/dE or the dispersion dn/d&lgr; of the two materials differ from each other such that when the temperature, the electric field or the wavelength of or in the two waveguides is change, the result will be effects of different powers.

Abstract: The invention relates to a device for determining a fixation point (3) on screen (1), comprising an eye reference point detector (6) an a direction of view detector (9) which is mounted on a pivoting/inclining element (11) in such a way that it can be pivoted and inclined. By means of three transformation steps, namely rotation, scaling and translation, a direction of view function can be transformed by a system of direction of view coordinates assigned to the direction of view detector (9) in an object coordinate system which is assigned to the screen (1). In this way it is possible, to trigger certain functions by fixation of areas of the screen (1) rendered sensitive, whereby the eye plays the role of a mouse.

Abstract: The invention relates to a device for superposing optical signals of different wavelengths. The device is provided with a light guide grid disposed between an input free beam coupler and an output free beam coupler, the input free beam coupler being provided at its input side with at least two input light guide units and an output light guide unit including a plurality of output light guides being to the output side of the free beam coupler. The aperture areas of the input light guide units are arranged and dimensioned relative to the the aperture areas of the output light guides such that each output light guide is affected by at least two optical signals of different wavelengths from the input light guides.

Abstract: In an integrated structure of a beam spread transformer with several buffer layers separated from each other by light guiding layers there is provided on the upper buffer layer an unclad rib waveguide with a tapered section. Between the fiber-facing interface and the tapered section there is provided a section over which the rib is extending. There, the waveguiding layer is completely removed and the exposed buffer layer is reduced symmetrically to a width which is greater than the width of the rib. By the additional rib thus formed coupling independent of polarization is made possible. The coupling is optimized by increasing layer thicknesses of the buffer layers.

Abstract: A digital optical switch with two input terminals and two output terminals to satisfy the extensive uses of optical switches. The conditions for adiabatic mode evolution can be flexibly adjusted depending on the planned use for said switch, the technological production thereof still being simple. In the digital optical switch according to the invention, the first incoming waveguide, with regard to the second incoming waveguide in the input section and the third outgoing waveguide with regard to the fourth outgoing waveguide in the output section are symmetrical with each other in cross-section, index of refraction and arrangement in relation to the direction in which the light spreads. Structural electrodes have a tapering effect on the wave guides and are adjusted thereto, and an electrode arranged in the output section is electrically driven.

Abstract: For reducing power consumption and cross-talk in the transmission of broadband optical signals without prior conversion into electrical signals there are provided in a thermo-optical switch two waveguides (WL1 and WL2) extending closely adjacent each other over their interactive length the width of which is at least partially covered by one or two pairs of lamellate electrode arms of a heating electrode (E), the arms of each pair being interconnected by a common web (G) and being of similar geometric shape as the waveguides (WL1 and WL2) positioned below them. Furthermore, means is provided for changing and/or setting the thermal and/or geometric symmetry/asymmetry of the refractive indices in the two waveguides.

Abstract: A Q-switched semiconductor laser is supposed to facilitate high-frequency laser modulation with low currents or voltage ranges. According to the invention, a laser of this type consists of at least one continually pumped active medium and two optically coupled resonators at least one of which is passive, both resonators having different mode combs corresponding to the Nonius principle, at least one resonator mirror taking the form of a reflector with strongly dispersive reflection characteristics in the laser wavelength range selected by the double resonator, the index of refraction of the passive resonator and/or reflector capable of being adjusted electronically.

Abstract: In a self-pulsing multi-section laser having two DFB sections, a Fabry-Perot-like resonator formed from two reflectors and a spacer is integrated into the multi-section laser and optically coupled to at least one DFB section. The spacer has a similar layer structure to the adjacent DFB sections (D.sub.1 and D.sub.2) but not DFB grid and takes the form of a control section operable electrically separated from the DFB sections. Selection is unnecessary. The self-pulsing two-section DFB laser of the invention with an integrated control section is suitable for optical beat regeneration in high-rate communication systems.

Abstract: The invention concerns optoelectronic circuits for an optical wavelength multiplexing system, the circuits being constructed with optical couplers (11; 39.2, 39.4) each having four branches (1,2,3, 4; 39.1, 39.3, 2.times.39.5; 2.times.39.6, 39.3, 39.7). Electrical and optical crosstalk is minimized both in integrated (FIG. 1) and hybrid (FIG. 5) constructions. To this end, photo diodes (6', 6"; 36) and laser diodes (5; 38) are each disposed on opposite sides of the couplers (11; 39.2, 39.4) and mutually decoupled by wavelength-selective arrangements of gratings (8, 10', 10") or filter plates (35). The circuits can be designed for bidirectional operation (FIG. 1) and for cascadable modules for multiplexers/demultiplexers with an add-drop function (5) and enable transmission and reception to be carried out simultaneously.

Abstract: An optical frequency generator provided with an optical comb generator for generating a plurality of frequencies including a central frequency and side bands spaced by a frequency transmitter. The central frequency is adjustably combined with the spectral component of a reference light source. Modification of frequency differences between the central frequency and the reference light source and modification of the transmission frequency of the frequency transmitter displaces the frequency comb of the comb generator or alters its spectral width. A heterodyne receiver connected to the output of the comb generator and a test light source of unknown frequency is provided for determining the frequency of the latter.

Abstract: The invention relates to a wavelength converter for converting a first light signal used for data transmission and having a first wavelength (.lambda..sub.in) into a second light signal having a second wavelength (.lambda..sub.out). The wavelength converter signal comprises a signal input for picking up the first light signal, a signal output for emitting the second light signal, a modulatable optical semiconductor amplifier (4) with an input, an output and modulation input and a first laser light source (L1), which forms a first stage with the semiconductor amplifier (4). The input of the semiconductor amplifier (4) is connected to the first laser light source (L1) and the modulation input of the semiconductor amplifier (4) is connected to the signal input for cross amplification modulation. The first laser light source (L1) emits light with a third wavelength (.lambda..sub.int).