Abstract: A microphone includes a first diaphragm and a second diaphragm coupled to the first diaphragm by a closed air volume. The first diaphragm and the second diaphragm each constitutes a piezoelectric diaphragm. The first diaphragm and the second diaphragm are electrically coupled so that movement of the first diaphragm causes movement of the second diaphragm.

Abstract: An electrical module includes a base plate having an acoustic channel that opens into a first cavity at a first end and that is closed off by a microphone chip at a second end. The microphone chip borders a second cavity that opens to an exterior of the electrical module. The second cavity is separated from the acoustic channel by the microphone chip.

Abstract: Elements and methods for forming elements that operate with acoustic waves are disclosed. The element includes a piezoelectric electric substrate that has a first thermal coefficient of expansion, electrically conducting element structures on an upper side of the substrate, a compensation layer on an underside of the substrate, and an SiO2 layer over the element structures.

Abstract: The invention relates to a microphone membrane (M1) comprising two piezoelectric layers (PS1, PS2) with c-axes oriented in the same direction. A first electroconductive surface (E11) is formed in the central metal layer and subjected to a first electrical potential. The piezoelectric layers (PS1, PS2) are respectively arranged between the central metal layer (ML2) and an outer metal layer (ML1, ML3). In a preferred embodiment, the membrane (M1) has a largely symmetrical structure in terms of the layer sequence and the layer thickness thereof.

Abstract: An apparatus including a piezoelectric substrate having at least one transducer electrode structure. The structure having a metallization formed by one or more metals with a mean specific density that is at least 50% higher than that of aluminum. The structure having a compensation layer that is applied fully or partially over the metallization. The compensation layer is of a material having a temperature dependence of elastic constants that counteracts the temperature coefficient of frequency of the substrate. The compensation layer has a thickness that is less than 15% of an acoustic wavelength of a wave capable of propagation in the structure.

Abstract: A microphone includes a first diaphragm and a second diaphragm coupled to the first diaphragm by a closed air volume. The first diaphragm and the second diaphragm each constitutes a piezoelectric diaphragm. The first diaphragm and the second diaphragm are electrically coupled so that movement of the first diaphragm causes movement of the second diaphragm.

Abstract: An electrical module includes a base plate having an acoustic channel that opens into a first cavity at a first end and that is closed off by a microphone chip at a second end. The microphone chip borders a second cavity that opens to an exterior of the electrical module. The second cavity is separated from the acoustic channel by the microphone chip.

Abstract: Elements and methods for forming elements that operate with acoustic waves are disclosed. The element includes a piezoelectric electric substrate that has a first thermal coefficient of expansion, electrically conducting element structures on an upper side of the substrate, a compensation layer on an underside of the substrate, and an SiO2 layer over the element structures.

Abstract: SAW component with improved temperature coefficient of frequency To reduce losses in a SAW component assembled on a piezoelectric substrate (S), the mass load on the metallization (M) is increased until the propagation velocity of the surface wave comes to rest below the propagation velocity of the fast shear wave. To limit the increase in the temperature coefficient of frequency in this process, a metallization with a significantly higher specific density than [that of] Al is used. The temperature coefficient of frequency of the component is simultaneously reduced by a compensation layer (K) applied to essentially the entire surface, said compensation layer being made of a material having a temperature dependency of the elastic coefficient that counteracts that of the substrate-metallization combination.

Abstract: In the manufacture of a fiber fleece with a nonwoven producing means and a fleece laying machine, which produces from a single or multi-layered nonwoven web contionuously discharged by the nonwoven producing means a fleece web having a thickness variable across the laying width, the nonwoven web is cyclically drawn on the way between the nonwoven producing means and the fleece laying machine at a fixedly determined location, said drawing depending on the laying movements of the fleece laying machine to form a fleece web of a regular cross sectional profile. Between a separate drawing equipment performing the drawing process and the inlet into the fleece laying machine, the nonwoven web may run through a separate, variable buffer storage, which adapts the speed fluctuations of the nonwoven web on the outlet side of the drawing equipment to the intake speed of the fleece laying machine.

Abstract: An integrated optical arrangement operated as a switch composed of at least three ridge waveguides on a substrate, the third ridge waveguide is utilized for an infeed of an optical waveguide proceeding between two parallel ridge waveguides forming the first and second waveguides having either a contacted pn-junction or a contacted pin-junction. As a result of asymmetrical switching of the junctions, the optical wave is coupled over into one or the other of the first and second waveguides. The advantage over traditional directional coupler switch structures are complete symmetry of the two switch conditions, "digital switching behavior", enhanced separation of the output waveguide, low switching losses and greater manufacturing tolerances, reduced polarization sensitivity and increased optical bandwidth.

Abstract: An integrated optical arrangement having at least one optical waveguide integrated a substrate of semiconductor material, characterized by the waveguide being a rib waveguide comprising the p-doped material disposed on a substrate which contains a waveguiding layer which is either an n-doped or an undoped material, said arrangement having either a pn or a pin junction between the p-doped material of the rib and the n-doped or undoped material of the waveguiding layer. In addition, a method for forming the various layer is disclosed.

Abstract: A method for generating a lattice structure with a phase shift on a surface of a substrate characterized by the steps of exposing of a photo-sensitive surface in an optical interference field and then subsequently exposing the same surface to a second interference field with the spatial frequencies of the two interference fields being changed a small amount between the two exposures. The photo-sensitive surface can be a photoresist layer applied on the substrate. After developing of the layer, this lattice structure is produced by etching. Another embodiment of the method is produced by means of a laser-active etching wherein the photo-sensitive surface is compound of a substrate surface in contact with an etchant and the etchant reaction is activated by the exposure.

Abstract: A monolithically integrated WDM demultiplex module has a film wave guide of InGaAsP fashioned on a substrate, a photodiode of InGaAs being applied to the film wave guide. The photodiode is optically coupled to the film wave guide by a leakage coupling. A wavelength selection element in the form of a grating is provided in the surface of the film wave guide. The module can be manufactured with a single epitaxial step. Structures for increasing the crosstalk attenuation of the module and for a better coupling-in of radiation into the module are provided.

Abstract: A method for integrating a DFB laser and a passive strip waveguide on a substrate. A layer stack is produced in a first epitaxy step, the layer stack having a laser-active layer and a surface-wide grating on the uppermost layer, and eroding the stack area-wise, but only down to a layer under the laser-active layer, not down to the substrate, by means of etching to create a step separating the laser region from the passive strip waveguide region. By employing an etching stop layer, the etching can ensue self-adjustingly, and the coupling between the laser-active layer and the passive strip waveguide region occurs not by end coupling, but by surface coupling. Only two epitaxy steps are required for the complete manufacture of the structure, and a strip required for the definition of the laser and of the waveguide can be produced in the same single method step.

Abstract: A window function optimum for apodization of diffraction at an aperture of a Bragg Cell spectral analyzer. A window function is derived which is simpler to realize and which comes very close to an optimum window function.

Abstract: A Bragg cell spectral analyzer with a prism expansion system for a laser beam, which has a Gaussian cross-sectional distribution of light intensity, is generally superimposed with stray light, and is conducted along a path through the system to a Bragg cell characterized by an aperture diaphragm being positioned in the path before the prism expansion system with the diameter of the aperture being selected to be larger than the half-width value of the Gaussian cross-sectional distribution. The prism expansion system only expands the laser beam to such a degree that the half-width value of the Gaussian cross-sectional distribution is smaller than the diameter of an aperture of the Bragg cell. As a result thereof, the diffraction side lobes of the spectrum can be reduced by apodization relative to the principal maximum of the spectrum and stray light contained in the laser beam can be blanked out.

Abstract: The aim of the present disclosure is to provide an arrangement for the production of x-ray sectional pictures by means of which the layergram can be filtered in a rapid and simple manner. The recording medium possesses a modulation transmission function having high-pass or band-pass filter characteristics.