Abstract:
Es wird eine Infrarot-Lichtquelle angegeben, umfassend ein Substrat, das wenigstens eine einkristalline Siliziumschicht aufweist und das in einem Teilbereich eine Membran aufweist, wobei die Dicke der Membran weniger als 200 μm beträgt und wobei die Membran einen Teil der einkristallinen Siliziumschicht umfasst, wobei das Substrat wenigstens eine Diffusionssperrschicht zur Verminderung der Oxidation der einkristallinen Siliziumschicht aufweist, wobei die Diffusionssperrschicht wenigstens die Membran bedeckt, wobei die Infrarot-Lichtquelle weiterhin eine auf der Membran angeordnete Deck-Schicht umfasst, die eine Emissivität von wenigstens 0,85 aufweist.
Abstract:
Eine Infrarotstrahleranordnung für ein Gasanalysengerät besteht aus einem Strahlergehäuse, in dessen einseitig mit einem strahlungsdurchlässigen Fenster abgeschlossenen Innenraum ein plattenförmiger Keramikkörper (3) angeordnet ist, auf dem eine Heizwiderstandsschicht (4) aufgebracht ist. Um eine sichere und exakt definierte Halterung des Keramikkörpers (3) zu gewährleisten, ist dieser als gleichseitige Dreiecksplatte (5) ausgebildet, die mit ihren Dreiecksspitzen (6) an dem Innenumfang des Strahlergehäuses (1), vorzugsweise in einer Umlaufnut (7), gehalten ist.
Abstract:
A gas sample chamber (10) for use in a gas analyzer consists of an elongated hollow tube (21) having an inwardly-facing specularly-reflective surface (22) that permits the tube to function also as a light pipe for conducting radiation from a source (20) to a detector (16) through the sample gas. A number of apertures (24) in the wall of the elongated hollow tube permit the sample gas to enter and exit. Particles of smoke and dust of a size greater than 0.1 micron are kept out of the chamber by use of a semi-permeable membrane (28) that spans the apertures in the hollow tube. Condensation of the sample gas components is prevented by heating the sample chamber electrically to a temperature above the dew point of the component of concern.
Abstract:
A light source and a method for its use in an optical sensor are provided, the light source including a resistively heated element. The light source includes a power circuit configured to provide a pulse width modulated voltage to the resistively heated element, the pulse width modulated voltage including: a duty cycle with a first voltage; and a pulse period including a period with a second voltage, wherein: the duty cycle, the first voltage, and the pulse period are selected so that the resistively heated element is heated to a first temperature; and the first temperature is selected to emit black body radiation in a continuum spectral range. Also provided is an optical sensor for determining a chemical composition including a light source as above.
Abstract:
The present invention concerns an apparatus for radiometric measurement of thin fluid films. It has a housing (1) enclosing means of radiation, a radiation guide, a reflector (4) and one or more detectors (5). The means of radiation is normally an IR radiator (2). The radiation guide is either a radiation tube (3) or a radiation cone (7). The reflector (4) is of the type non-imagining optics. If there is more than one detector (5) normally at least one detector is a reference detector.
Abstract:
A miniature source of modulated infra-red energy comprises a very thin heated wire strip (11) of low mass, mounted in a tensioned state by means of two resilient members (18), and a reflector (15) positioned behind the wire (11) so as to enhance the radiated energy. The source is hermetically sealed in an inert atmosphere with a cap (20). The cap (20) has an aperture (16) through which the energy emerges, this is sealed either with a window or a filter (17) if a specific wavelength is desired.
Abstract:
Die Erfindung betrifft eine photoakustische Gassensor-Vorrichtung (30, 50, 60) mit: einem Messraum (16) zur Aufnahme eines zu messenden Mediums, einer Strahlungsquelle (10), einer ersten an den Messraum (16) angeschlossenen photoakustischen Messzelle (32), die zum Erfassen eines ersten Gases (33) eingerichtet ist, und einer optischen Einrichtung zum Leiten von aus der Strahlungsquelle (10) ausgesandter Strahlung durch den Messraum (16) zu der ersten photoakustischen Messzelle (32). Um mit einer kompakten Einheit mehrere Sensoraufgaben lösen zu können, wird vorgeschlagen, dass wenigstens eine zweite photoakustische Messzelle (34), die zum Erfassen wenigstens eines zweiten, unterschiedlichen zu messenden Gases (35) eingerichtet ist, an den Messraum (16) angeschlossen ist und dass die optische Einrichtung von der Strahlungsquelle (10) ausgesandte Strahlung (12) durch den Messraum (16) hindurch hin zu der ersten und zu der zweiten Messzelle (32, 34) leitet.
Abstract:
A method and apparatus are described for driving a modulated radiation source (which can be, for example, an infrared light source). The method affects the power driving a light source in such as way so as to minimize the warm-up time of the source. The apparatus permits feedback control of a light source to specified powers or temperatures. Disclosed embodiments can improve source performance and lifetime and decrease the operating costs of the source.
Abstract:
The invention relates to a transmission spectrometer for analysing a liquid sample with regard to a medically significant component, in particular a bodily fluid, preferably in the middle infrared spectral range MIR. Said spectrometer comprises: a cell (3) with opposing transparent walls (4, 5) for holding the sample; a light source (2) for emitting radiation, which passes through the opposing walls (4, 5) of the cell (3) and is partially absorbed by the sample; a plurality of filters (8a-8p) that are arranged on one of the walls (5) of the cell (3) and that are respectively permeable to a wavelength range, in which the medically significant component of the sample causes absorption maxima; a plurality of detectors (9a-9p), which are respectively associated with one of the filters (8a-8p), for detecting the intensity of the radiation that passes through the cell (3) and the respective filter (8a-8p); and an evaluation unit (10), which is connected to the detectors (9a-9p) and determines an analytical result from signals that are generated by the detectors (9a-9p) in accordance with the detected intensity. According to the invention, one of the opposing walls (5) of the cell (3) supports the detectors (9a-9p).
Abstract:
A radiation arrangement suitable for emitting IR radiation has a flat radiation source (2), the radiation emitted from which is deflected in at least one predetermined direction by a reflector (4); said reflector consists of a body, the circumference of which becomes smaller towards the beam outlet and the reflective surface of which is substantially surrounded by the radiation source; in an axisymmetrical arrangement, the distance between the radiation source and the axis of the reflected beam is greater than the radius of the reflector component arranged symmetrically in rotation along the optical axis. The radiation body may consist thereby of a resistive coating (2) on an electrically insulating substrate (3) or a self-supporting resistive strip or wire. An essential advantage here is that there is a relatively large area for the generation of IR radiation which can be bunched into a high-intensity beam by the reflector arrangement, as is necessary in measuring instruments, e.g. gas analysers.