Abstract: A radiant source including an essentially planar substrate having a well or hole formed therein. At least one incandescent filament is mounted to the substrate and aligned at the well or hole. Contact pads are formed onto the substrate, to both ends of the incandescent filament, and feed electric current to the incandescent filament. Furthermore, each incandescent filament is doped with phosphorus to an impurity concentration of at least 5.times.10.sup.19 atoms/cm.sup.3.

Abstract: A calibration method for gas concentration measurement with an NDIR technique based on optical absorption. Radiation is imposed onto the gas mixture under measurement contained in a measurement channel (3) isolated at least partially from its environment, the intensity of radiation transmitted through the gas is measured, the gas concentration is computed from the measured intensity, in order to calibrate the measurement apparatus the gas state variables are deviated in a controlled manner, whereby the level of transmitted radiation intensity is changed, and the intensity of the transmitted radiation is measured in at least two known points of the gas state variables, thus obtaining data for calibration of the measurement apparatus employed.

Abstract: A method and an apparatus for measuring dewpoint of different kinds of gases, is based on cooling the measured gas, with the help of cold gas, down to the dewpoint and then detecting the generated mist by optical sensors. The cooling gas is routed to a measurement area (7) from outside the process and the cooling gas is brought to an appropriate temperature below the dewpoint of the measured gas before being conducted to the measurement area (7). Mist generated during the cooling of the measured gas is detected by illuminating the measurement area (7) by a light emitting source (8) and measuring the light (2) scattered from the mist or light (3) penetrating through the mist with the help of a photodetector (9). The temperature of the measurement area is continuously monitored with temperature sensors (10) so that when the mist is detected, the temperature of the measurement area (7) at that instant corresponds to the dewpoint temperature of the measured gas.

Abstract: An apparatus and method measures the concentration of a gas. The apparatus comprises a radiation source (70) for emitting radiation onto the gas (79) to be measured, whereby the radiation source (70) is comprised of an anode (4) and a cathode (9), and as an emitting fill gas the same as the gas (79) to be measured; and a radiation detector (74) with which the radiation transmitted through the gas (79) to be measured can be detected. The cathode (9) functions as an electron emitter, and between the anode (4) and the cathode is connected such a low operating voltage that does not cause ionization or essential dissociation of the emitting gas. The design provides an approximate temperature tracking of the radiation source with the ambient temperature.

Abstract: In a novel multilayer transducer (1') with bonded contacts and a method for fabricating the bonded contact areas (5') of the transducer, the contact areas (5') are formed on the side surface (7) of the transducer by metal deposition using laser-based deposition, sputter deposition or another suitable metallization method. By virtue of the fabrication method of the contact areas, the size of the transducer (1')can be reduced and the transducer (1') can be bonded to a circuit board using surface-mount technology.

Abstract: A method and an apparatus for measuring dewpoint of different kinds of gases is based upon cooling the measured gas by mixing it with a cold gas down to the dewpoint and then detecting the generated mist by optical sensors. The cooling gas is routed to a measurement area (7) from outside the process and the cooling gas is brought to an appropriate temperature below the dewpoint of the measured gas before being conducted to the measurement area (7) where it is mixed with the measured gas. Mist generated during the cooling of the measured gas is detected by illuminating the measurement area (7) by a light emitting source (8) and measuring the light (2) scattered from the mist or light (3) penetrating through the mist with the help of a photodetector (9).

Abstract: Disclosed herein is a humidity calibrator device including a base part sealed by plugs, and a replaceable humidity calibrator cartridge. The cartridge contains saturated vapor, saturated salt solution and salt crystals. The cartridge is sealed with a semipermeable membrane and an air-tight protective peel-off foil. The semipermeable membrane, which seals the part of the humidity calibrator cartridge entering the base part of the apparatus provides a separation of the compartment in the base of the apparatus and liquid containing space of the cartridge, allowing permeation of water vapor and preventing permeation of the liquid.

Abstract: The invention concerns a sensor construction for, e.g., the measurement of gas concentration, including a sensor element; a heating element arranged in conjunction with the sensor, with which the sensor element can be brought to a temperature above the ambient gas atmosphere temperature; and an electronics circuitry section, with which the desired electrical properties of the sensor element can be measured and the heating element of the sensor can be controlled. According to the invention, the sensor element and the electronics circuitry are placed onto the same planar substrate, and the substrate is processed to have adjacent openings around the sensor element area to the immediate vicinity of the area so that the openings extend through the substrate whereby the sensor area is connected to the surrounding part of the substrate and, then, to the electronics circuitry section, only along thin isthmuses remaining between the openings.

Abstract: A pressure transducer comprises a sensor (16), an electronic circuitry part (17), a pressure connection (13), and an electrical connection (14). According to the invention, the transducer is constructed as a plug-in unit (5) and both the pressure connection and the electrical connection (14) are designed integral with the socket (6). The plug-in unit (5) may incorporate a splash-water protection (8) with a latch mechanism (9) for locking the plug-in unit (5) and the socket (6).

Abstract: This invention concerns a method for trimming a planar capacitor. According to the method, a laser emission is focused to an electrode of a capacitor formed on a substrate transparent to laser emission and including of an upper electrode, an insulation layer, and a lower electrode, in order to achieve a passivation effect on the electrode. The laser emission is focused according to the invention locally onto the lower electrode through the substrate in order to achieve a heating effect on the lower electrode, thereby oxidizing the electrode material so that the lower electrode is locally converted into an electrically nonconductive state while being protected by the substrate and the insulation layer. The trimming method in accordance with the invention is accurate and offers a stable capacitance value.

Abstract: Described herein are a capacitive pressure detector, with an electrically conductive substrate (1), an electrically conductive, plate-like member (3) disposed at a distance from the substrate, and an electrically insulating layer (2') hermetically bonding together the substrate (1) and the member (3) such that a capacitor chamber is formed between the substrate (1) and the member (3), as well as a method for manufacturing same. The method comprises machining at least one recess (5) into one side of the substrate (1), applying a layer (2) of electrically insulating material in molten state onto the machined side of the substrate (1) such that the layer (2) covers the machined side of the substrate, allowing the layer (2) to harden, remowing material out of the surface of the structure in this way produced for obtaining a substantially plane surface with at least one conductive mesa portion (6) of the substrate (1) surrounded by at least one insulating layer portion (2').

Abstract: The characteristics of various solid materials, in particular, surfaces of and coatings on metals and thickness of surface hardening layers are measured without damaging the specimen. The phase angle of a continuous thermal surface wave produced by a modulated light beam is measured. The phase angle of the continuous thermal wave progressing along the surface of the specimen is measured by temperature detectors either at a fixed distance from the light spot, as a function of frequency, or at a fixed frequency, as a function of distance. The phase angle of the thermal wave depends upon the thickness of the surface hardened layer whereby such thickness is measured.

Abstract: The present publication describes a capacitive humidity sensor and a method for the manufacture of same. The sensor comprises a substrate (1), first (5) and second bottom electrodes (4), which have been fitted close to each other on the substrate (1), an active layer (7), which fills the area between the first (5) and the second bottom electrodes (4) on the substrate (1) and extends to above the top face of the second electrode (4). According to the invention, the sensor further consists of structures (6) connected to the top face of the first electrode (5), made of a conductive material, and being beam-shaped with an upwardly widening section and being placed side by side, the said structures (6) limiting portions (7) of the active layer between themselves from two sides, and a narrow slot (26) being provided between the top faces of the said structures. Owing to its construction, the sensor is not sensitive to touching.

Abstract: A method for detecting and measuring electromagnetic or particle radiation by electrical means has been provided. A piece of semiconductor material, such as phosphorus-doped silicon, fitted with at least two electrodes is used as the detector and the measurement is performed by exposing the detector to the radiation to be measured and by applying an electric field between the electrodes, which will cause an electric breakdown after a certain delay time. The length of this delay time preceding the breakdown is altered by radiation and the magnitude of the change is serving as a measure of the intensity of the radiation falling on the detector.