Abstract: A device for physiological pressure monitoring comprises a miniaturized pressure sensor element which is located near the tip of a guide, which in turn is inserted into a catheter. The guide and the catheter have sealing surfaces which can be brought into contact with each other by axial or rotary motion of the guide in relation to the catheter, whereby the sensor element becomes available for calibration from a pressure generator connected to the catheter.

Abstract: A fiber-optic sensor for sensing dynamic acceleration is arranged so that the acceleration gives rise to changes in angle between at least one body and the optical axis of at least one lens of graded index type (GRIN lens). At least one optical fiber is arranged to transmit optical energy to and from one end surface of the lens. The optical energy reflected back into the fiber is dependent on the angle and essentially independent of the distance between the body and the lens, and the sensor comprises at least one photoluminescent material so that a part of the optical output signal from the sensor includes a photoluminescent signal.

Abstract: A fiber-optic measuring device for measuring physical quantities, comprising a transducer unit and an electronic unit which are interconnected by means of at least one optic fiber. The measuring transducer unit comprises at least two photoluminescent elements, of which at least one is positioned in the ray path of light from the fiber, at least partly behind another element. The physical quantities to be measured are arranged to influence the light transmission between the photo-luminescent elements. The electronic unit includes at least two light sources having different emission spectra which are so chosen in relation to the absorption and transmission spectra of the photo-luminescent elements that one light source is arranged to excite substantially one of the photo-luminescent elements whereas the other light sources at least partly excite the other element or elements.

Abstract: The temperature-measuring transducer of a temperature-measuring system that includes a device for emitting energizing radiation, a temperature-measuring transducer which, upon excitation by the energizing radiation, will emit luminescent light, a detector for detecting the luminescent light emitted by the temperature-measuring transducer, and at least one optical fiber interconnecting the various elements is made of a crystalline sensor material which contains luminescent ions, at least some of these luminescent ions being so located in the crystal lattice of the sensor material that for each of said at least some luminescent ions each immediately adjacent anion substantially shows inversion symmetry in relation to that luminescent ion.

Abstract: A fiber optical measuring device for measuring dynamic movements between a boundary surface of an optical fiber and a boundary surface of a movement-sensing body. The optical fiber is adapted to transmit optical energy to and from the boundary surfaces and at least one of the boundary surfaces includes a photo-luminescent material, the optical energy reflected from the boundary surface of the body being dependent on the relative position between the two boundary surfaces.

Abstract: A fiber-optic sensor for measuring a physical quantity or sensing changes therein, consists of a transmitter and receiver unit respectively arranged to transmit and receive optical energy and an optical fiber for transmission of said optical energy to and from a sensor located at the measurement point. The sensor has at least one solid body, which is arranged to emit photoluminescent optical energy in at least one wavelength range, and a volume limited by at least two substantially plane-parallel surfaces, the separation of which is smaller than half the coherence length for either the transmitted or luminescent optical energy, whereby an interference pattern will differently affect the transmission of optical energy to the receiver unit as the optical length between said parallel surfaces changes with changes in the physical quantity being sensed.

Abstract: An optical sensor for detecting changes in physical quantities such as temperature, position, force, level, pressure, flow, acceleration, magnetic or electrical field strength or mechanical deformation, includes a luminescent material built up of atomically localized luminescence centers, included as a solid solution in an amorphous or mono-crystalline bonding material.

Abstract: A fiber optical luminescence measuring system for measuring a change in a physical quantity employs a transmitter/receiver unit and a sensor unit for the physical quantity optically linked by at least one optical fiber. The sensor unit is arranged to emit luminescent light with at least two different decay time constants, where the quotient between the intensities of emitted luminescent light having the different decay times corresponds to a measure of the quantity to be measured.

Abstract: A fiber optical measuring apparatus suitable for measuring physical quantities such as position, speed, acceleration, force, pressure, elongation, temperature, etc., comprises at least one optical fiber for conducting incident light between an electronic unit and a sensor, the sensor comprising at least one luminescent element. The measuring apparatus is characterized in that the physical quantity to be measured is arranged to influence the position of an optical spectral filter, for example of absorption or interference type, relative to the optical fiber in the sensor and/or relative to said luminescent element, and that said spectral filter is arranged to be situated, to a greater or lesser extent, between the end surface of the optical fiber and at least one of the luminescent elements.

Abstract: An hermetic seal at a smooth interface between a gallium arsenide body and a glass body is effected without organic or inorganic binders by thermally bonding the bodies at the interface while ensuring that the oxygen concentration at the interface is so low that there is no optically detectable variations in color of the gallium arsenide close to the interface.

Abstract: In an exemplary embodiment, a measuring cell is disposed in an outer tube. A chamber in the outer tube adjacent the measuring cell can be directly connected via an opening to the liquid in a liquid vessel whose pressure is to be measured. In order to also be able to calibrate the pressure transducer at any time in the liquid vessel, an elastic container is inventively disposed in the chamber, the container being connected to a connecting line likewise lying in the outer tube for the purpose of filling and emptying. In its filled state, the container closes the opening of the chamber without interrupting the connection between a fluid line used for calibration and the measuring cell.

Abstract: A capacitive transducer indicates the value of a physical quantity to be measured and is constructed with two spaced electrically conducting plates movable relative to one another in response to a mechanical signal representative of the physical quantity to be measured to generate an electrical signal in response thereto with the transducer capacitor being actuated and de-actuated to be respectively responsive and non-responsive to the mechanical signal in accordance with pre-designated time intervals. The electrical signal in accordance with the capacitance of the transducer capacitor is integrated to provide an output signal when the integrated signal exceeds a reference value.

Abstract: In an exemplary embodiment, an electrical signal is to be generated corresponding to the pressure to be measured. The pressure transducer is formed by an outer tube in which a measuring cell as well as a liquid line connected to a liquid reservoir are disposed. In order to be able to calibrate the pressure transducer at the respective place of measurement, for example, a blood vessel, the disclosure provides that the open end of the outer tube is closed by a one-way valve through which fluid can only flow out in the direction from the tube. When a slight, specific underpressure is set, the one-way valve closes and the pressure transducer can be calibrated.

Abstract: In an exemplary embodiment, a measuring cell is formed by an interior tube open at one end and within a surrounding exterior tube. The interior tube is adapted to contain a gas while a chamber within the exterior tube at the open end of the interior tube can be filled with a pressure transmission liquid via a channel extending within the exterior tube and along the length of the interior tube and leading to the chamber. For a pressure measurement, the liquid in the chamber can communicate directly with a liquid in a liquid vessel, e.g. a blood vessel. In the measuring cell electrodes are arranged for generating an electric signal which corresponds to the gas volume in the measuring cell and thus the liquid pressure in the chamber. The measuring cell is disposed with its open end opposite a lateral opening in the wall of the exterior tube.

Abstract: In an exemplary embodiment, the liquid pressure to be measured is in a liquid container with an inner tube forming a measuring cell arranged in an outer tube, which measuring cell can be filled in part with a liquid and in the remainder with a gas. A conduit that can be filled with the liquid leads away from the measuring cell, which conduit is open on its end facing away from the measuring cell and can be directly connected with the fluid in the liquid container. A transducer for generating an electric magnitude which corresponds to the gas volume in the measuring cell is arranged in the measuring cell. A channel is left free between the outer tube and the inner tube for the passage of the fluid. The inner tube is closed on its end facing away from the measuring end of the pressure transducer.

Abstract: A pressure transducer including a measuring cell which is partly filled with a liquid and with the remainder being filled with a gas; a conduit filled with the liquid extending from the measuring cell, and which is open at an end thereof remote from the measuring cell; and means in the pressure transducer for generating an electrical value which corresponds to the particular gas volume.