Abstract: A high pressure gas discharge lamp and the method of making same utilizing integrated circuit fabrication techniques. The lamp is manufactured from heat and pressure resistant planar substrates in which cavities are etched, by integrated circuit manufacturing techniques, so as to provide a cavity forming the gas discharge tube. Electrodes are deposited in the cavity. The cavity is filled with gas discharge materials such as mercury vapor, sodium vapor or metal halide. The substrates are bonded together and channels may be etched in the substrate so as to provide a means for connection to the electrodes. Electrodeless RF activated lamps may also be fabricated by this technique. Micro-lasers may also be fabricated by this technique as well.

Abstract: The invention provides a method which can suitably be used to mass-produce semiconductor devices. This method includes the following steps: a) providing a silicon surface with an anti-reflective layer which is made predominantly from a mixture of polyimide and polyamidic acid, b) providing the anti-reflective layer with a photosensitive layer which is subjected to patterned radiation and then developed thus forming an etch mask of the photosensitive layer and the anti-reflective layer, c) etching the freed parts of the silicon surface, and d) removing the etch mask. The method in accordance with the invention is characterized in that, prior to applying the anti-reflective layer, the silicon surface is exposed to an oxidative treatment in which, preferably, an aqueous solution of hydrogen peroxide with ammonia or sulphuric acid is used. By virtue of this measure in accordance with the invention, the undesired etching away of small silicon structures is precluded.

Abstract: The invention aims to make an automatic information system suitable for the input of requests which are spoken as naturally as possible and which are not subject to restrictions about which the user must be informed in advance. To this end, the system and the method are subdivided into several, essentially independently operating segments with unambiguous interfaces. A first segment serves for the recognition of words and outputs a word graph. A second segment forms a concept graph from the word graph in that essentially the word graph is searched only for word sequences wherefrom values for a database enquiry can be derived; such word sequences, or also single words, are replaced by concepts in the concept graph. In a further segment the concepts in the concept graph are bridged and gaps between the concepts are filled. A speech model is taken into account for this operation.

Abstract: An optical unit for restoring a pulse pattern is described. The unit has an input for receiving a signal pulse series at a modulation period T and wavelength .lambda.hd p and comprises a pulsed laser for supplying a pulse series whose distance between two consecutive pulses is equal to n.T, in which n is an integer and is variable throughout the pulse series. Pulses of the signal pulse series can be injected into the pulsed laser. Moreover, the unit comprises at least a detection system arranged in the path of the radiation emitted by the pulsed laser, which system detects on the basis of a variation of a feedback-sensitive parameter of the laser.

Abstract: Optoelectric device having a coupling between a semiconductor diode laser component, such as an amplifier or modulator, and two optical glass fibres. The optoelectronic device has an optoelectronic module comprising a first holder with a semiconductor diode laser component and provided on either side of the component with a second holder comprising a plate with an opening and a lens holder in which a lens is present. The module also comprises a third holder for an optical glass fibre aligned with the component on either side of the component. The second holder comprises a bush which is connected to the plate and within which the lens holder is fastened to the plate, while the bush is provided with at least one opening, near the plate.

Abstract: The invention relates to a III-V laser (amplifier) with an active region (4A) which encloses a small angle with the end faces (50, 51), is separated therefrom by a preferably current-blocking cladding layer (5) and has a tapering end (40) of which a first side face (42) coincides with a side face (42) of the remainder of the strip-shaped active region (4A), while a second side face (43) thereof encloses an acute angle with the perpendicular to the end faces (50, 51). Such a laser has an amplification ripple, which is undesirable. In a laser according to the invention, the second side face (43) of the tapering portion (40) encloses an angle with the perpendicular to the end face (50, 51) which lies between 0.degree. and 30.degree., preferably between 0.degree. and 10.degree., and which is preferably approximately 0.degree.. The laser according to the invention has a particularly low reflection, as a result of which said amplification ripple is absent or at least very small.

Abstract: An electro-optical scanning device comprises a lens (2) having an optical axis (2a), which lens is movable in a focusing direction (F), related to the optical axis, to form at least one radiation spot on a surface to be scanned, and in a tracking direction (T), oriented transversely of the focusing direction, to follow a recording track. The scanning device comprises a stationary section (16) having first actuator means and a movable section (6) having second actuator means, which movable section is movable relative the stationary section and carries said lens, which actuator means cooperate electromagnetically with one another via an air gap (20) in order to drive the lens. The movable section is secured to the stationary section by elastically deformable suspension means.

Abstract: The invention provides a novel type of piezoelectric element. This element comprises a number of piezoelectric layers of a ceramic material and a number of electrode layers of a silver-palladium alloy. The piezoelectric layers and the electrode layers are stacked alternately to form a multilayer. This multilayer is also provided with at least two external electrical connections which are in contact with a number of said electrode layers. In accordance with the invention, the composition of the main component of the ceramic material corresponds to the formula:?Pb.sub.1-u-x Ag.sub.u RE.sub.x !?Ti.sub.1-y-z Zr.sub.y (W.sub.1/2 Mg.sub.1/2).sub.z !O.sub.3,where RE is at least one element selected from the group formed by La, Nd, Sm and Gd, and in which 0<u.ltoreq.0.025; 0.005.ltoreq.x.ltoreq.0.05; 0.44.ltoreq.y.ltoreq.0.52 and 0.015.ltoreq.z.ltoreq.0.1. Preferably, RE stands for La and 0.005<u<0.020. This material can be sintered at a low temperature and has a relatively high Curie temperature.

Abstract: An optoelectronic device with an optoelectronic module containing a semiconductor diode laser device and, in the radiation path (S) on either side of the semiconductor diode laser device, in that order, a first lens, an optical component, in particular an optical isolator, a second lens, and an optical glass fiber. The second lens and the glass fiber are arranged in a sub-module. The optical component is present in the sub-module and the first lens outside it, and the module is provided with means for fastening the sub-module to the module at an adjustable angle relative to the radiation path. Said means preferably comprise a membrane and radially adjustable clamping means.

Abstract: An optical transmissive component (1) is described, which component has an entrance surface (4) and an exit surface (5) for optical radiation (20), in which one of the surfaces (4; 5) is provided with an anti-reflection grating (10; 15). By providing a second surface, (5; 4) with a second anti-reflection grating and by ensuring that the grating strips (11) of the first grating (10) extend essentially perpendicularly to those (16) of the second grating (15) in corresponding areas of the first and the second surface (4; 5), it is prevented that the component is birefringent.

Abstract: An actuator comprises a permanent magnet body (1) and coil means for cooperation with the magnet body. The magnet body is rotatable about an axis of rotation (7) between, for example two, stop positions. The coil means exclusively comprise at least one active coil section (9a, 11a) of an electrical coil, which coil section extends parallel to the axis of rotation of the magnet body and substantially faces a magnet pole in a stop position of the magnet body.

Abstract: The invention relates to the field of integrated optics and communication techniques. In these fields, integrated, compact passive beam splitters and combiners are of great importance. These optical functions can be fulfilled by means of multimode interference (MMI) couplers. A given number of inputs is evenly distributed to all outputs. These components have wide manufacturing tolerances and are substantially independent of polarization. In the conventional MMI couplers with parallel sides, the intensity and phase distribution at the output are fixed. However, since in many applications, these distributions must be influenced in a controlled manner, the invention provides a method of changing the intensity and phase distributions at the outputs of MMI couplers in a controlled manner. The conventional MMI couplers are first split up into sections. Each section is then separately transformed so that the self-imaging properties are maintained. At the end, the sections are arranged in series again.

Abstract: Information is supplied to a bus in a wired logic function, the potential on the bus either being pulled down to ground level or remaining at supply level. The data line in a bus is split into two parts which are interconnected via the main current channel a transistor. Different supply voltages are used on the two parts. The control electrode of the transistor is connected to the lowest of the supply voltages. The transistor becomes conductive when either of the parts is pulled down. The transistor is non-conductive when none of the parts is pulled down.

Abstract: Speech recognition produces test signals from the speech signal which are compared with predetermined reference signals so as to form scores. Each subsequent test signal is compared with reference values which are situated within a predetermined neighborhood of the reference value which has been determined to be optimum for the preceding test signal. In dependence on this neighborhood, transition values in conformity with the transition probabilities are added to the scores. In order to enhance the results notably in the case of different speeds of speaking of the instantaneous speaker, it is proposed to adapt these transition values in dependence on the speed of speaking. A further improvement can be achieved by also adapting the reference values themselves to the relevant speaker's pronunciation. This adaptation can also be iteratively performed in a number of steps.

Abstract: A method and apparatus for repetitively imaging a mask pattern (C) on a substrate (W) are described. Various parameters of the apparatus and the projection lens system (PL) can be measured accurately and reliably and measuring devices of the apparatus can be calibrated by measuring a latent image of a mark by means of a scanning microscope (LID) forming a diffraction-limited radiation spot (Sp) on the photoresist layer on the substrate (W), in which layer the latent image is formed by means of a projection beam (PB).

Abstract: An integrated optical circuit comprises a first device and a second device, which devices are connected by a polarization convertor. The polarization convertor has one or more curved sections of a waveguide, integrated in the optical circuit. The conversion ratio is determined in part by the radius of curvature of the curved sections.

Abstract: An optical unit (1) is provided for optically scanning a surface, particularly an information surface of a recording medium (9). The unit comprises a frame (13), a radiation source unit (15), a rotatable mirror unit (17), and an objective system (19) for forming a scanning spot on the information surface, which objective system has an entrance pupil (19b) and an optical axis (19a). From an optical point of view, the rotatable mirror unit is situated between the radiation source unit and the objective system, suspension means being provided for movably supporting the objective system relative to the frame. The suspension means allow a longitudinal movement of the objective system along the optical axis and a pivotal movement of the objective system about a pivot which coincides with the point of intersection of the optical axis and the entrance pupil. Actuating means drive the objective system in accordance with these movements.

Abstract: The invention relates to a substrate made from a novel type of ceramic material. This material comprises 44-47 at. % A1, 31-39 at. % O, 8-13 at. % C and 8-12 at. % N. Substrates made from this material exhibit a relatively high heat conductance, a relatively great strength and their coefficient of expansion is equal to that of Si. Consequently, the substrates in accordance with the invention are very suitable for use in the Si-semiconductor technology. The main component of the ceramic material of the substrates preferably corresponds to the formula Al.sub.28 O.sub.21 C.sub.6 N.sub.6. The invention also provides methods of manufacturing substrates and other mouldings from this material.

Abstract: A semiconductor device with a bipolar transistor formed in a layer of semiconductor material (2) provided on an insulating substrate (1), in which material a collector zone (4), a base zone (5), and an emitter zone (6) are provided below a strip of insulating material (3) situated on the layer (2), which zones are connected to contact regions (7, 8, 9, 10) lying adjacent the strip (3), three of the contact regions (8, 9, 10) lying next to one another at a same side of the strip (3), of which two (8 and 9) are connected to the base zone (5) while the third (10), which lies between the former two (8 and 9), is connected to the emitter zone (6). The three contact regions (8, 9, 10) situated next to another at the same side of the strip (3) are provided alternately in the layer of semiconductor material (2) and in a further layer of semiconductor material (19) extending up to the strip (3).

Abstract: The properties of a diffusion barrier material layer over a semiconductor substrate are enhanced in a simple and time-effective manner by immersing the substrate in an oxidizing liquid. For a titanium-tungsten barrier metal, a dip in nitric acid for 1-60 minutes provides the metal with an oxide layer of the right thickness of 10-20 .ANG..