Abstract
A device (1) for determining the concentration of a gas component is configured with a radiation source (30) for radiating (31) light as a light emission in an infrared wavelength range. Two detector arrays (52, 62) with two detector elements (50, 60) are configured suitably for detecting the light emission generated by the radiation source (30) in two detector arrays (52, 62). Two filter elements (51, 61) are associated with the detector elements (50, 60). The two detector elements (50, 60) are oriented in relation to the radiation source, so that a range of overlap (65) is obtained due to the two detector arrays (52, 62). The range of overlap (65) causes attenuations in the propagation of light, which may be due to gas molecules or moisture (400). The attenuations in the propagation of light affect both detector elements (50, 60) and are compensated concerning the determination of the concentration.
Claims
1. A device for determining a concentration of a gas component in an inhaled gas or in an exhaled gas of a living being, the device comprising: a radiation source configured to radiate light as a light emission in a wavelength range of lambda1 (λ1)=2.5 μm to lambda2 (λ2)=14.0 μm; a first detector array comprising a first detector element configured to detect the light emission generated by the radiation source and a first array bandpass filter element arranged at the first detector element and which forms a detection surface for detecting the light emission generated by the radiation source; a second detector array comprising a second detector element configured to detect the light emission generated by the radiation source and a second array bandpass filter element arranged at the second detector element and which forms a detection surface for detecting the light emission generated by the radiation source; a flow channel configured to guide the flow of a gas flow essentially at right angles to a length axis of the light emission; a first light transmission element; a second light transmission element, each of the first light transmission element and the second light transmission element being configured to be optically transparent for the light emission in the wavelength range of lambda1 (λ1)=2.5 μm to lambda2 (λ2)=14.0 μm; a diaphragm element configured to guide a light beam from the radiation source to the detection surfaces of the first detector array and the second detector array; and a control unit configured to control operation of the radiation source and for detecting signals of the first detector element and the second detector element, wherein: one of the first array bandpass filter element and the second array bandpass filter element is configured to be optically transparent for infrared radiation, which is absorbed by a measured gas, wherein another one of the first array bandpass filter element and the second array bandpass filter element is configured as being optically transparent for infrared radiation which is not absorbed by the measured gas; a radiating surface of the radiation source is arranged at a radiation source distance (l.sub.3) from the detection surface of the first detector array and the detection surface of the second detector array; the second light transmission element is arranged as part of a wall of the flow channel; a distance (l.sub.F2) of the second light transmission element to the detection surfaces of the first detector array and the second detector array is related to the radiation source distance (l.sub.3) according to a relationship: a diaphragm element distance (l.sub.DB) from the detection surfaces of the first detector array and the second detector array to the diaphragm element is based on ratios according to a relationship: the first light transmission element is arranged as part of a wall of the flow channel; a distance (l.sub.F1) of the first light transmission element to the radiation source, in relation to the radiation source distance, is according to a relationship: the diaphragm element is arranged at or outside the flow channel with a ratio of a width extension (l.sub.B) of the diaphragm element in relation to a width extension (l.sub.S) radiation of the radiation source according to a relationship: the width extension (l.sub.B) of the diaphragm element in relation to the width extension (l.sub.S) of the radiation of the radiation source and a width extension of the first detector array and the second detector array (l.sub.D1,2) is based on ratios according to a relationship: whereby a range of overlap is obtained, in the flow channel for the light emission generated by the radiation source, between the first detector array and the second detector array.
2. A device in accordance with claim 1, wherein: the radiation source is configured as a flat radiator, as a diaphragm radiator or as a radiation element configured with a planarly configured radiating surface or as a light-emitting diode configured with a planarly configured radiating surface; the radiating surface is configured for a uniform radiation emission over the radiating surface; and the radiating surface of the radiation source is selected in a range of 2.0 mm.sup.2 to 10.0 mm.sup.2.
3. A device in accordance with claim 1, wherein: the first detector element and the second detector element are arranged at a first distance (l.sub.1) from the length axis in a range of 0.1 mm to 10.0 mm; the first array bandpass filter element and the second array bandpass filter element are arranged at the first detector element and the second detector element at a second distance (l.sub.2) from the length axis, extending between the first detector array and the second detector array in a range of 0.1 mm to 10.0 mm.
4. A device in accordance with claim 1, wherein the first array bandpass filter element and the second array bandpass filter element are configured for optical filtering of infrared light in a transmission range of a wavelength range of 2.5 μm to 14 μm.
5. A device in accordance with claim 1, wherein the first detector element and the second detector element are configured as pyrodetectors, bolometers, semiconductor detectors, thermopiles or thermocouples.
6. A device in accordance with claim 1, wherein: a space area, between the first detector array, the second detector array and the diaphragm element and/or a space area between the diaphragm element and the second light transmission element and/or a space area between the radiation source and/or the optically reflecting element and the first light transmission element and/or a space area between the second light transmission element and one of the first detector array and the second detector array is filled with an optically transparent material, which has an optical refractive index n>1.
7. A device in accordance with claim 6, wherein the length l.sub.F1, l.sub.F2 and l.sub.DB are physical geometric length extensions or as physical optical length extensions with inclusion of optical refractive indices of optically transparent materials between the diaphragm element and the second light transmission element and/or the diaphragm element and one of the first detector array and the second detector array and/or the radiation source and the first light transmission element and/or the second light transmission element and one of the first detector array and the second detector array.
8. A device for determining a concentration of a gas component in an inhaled gas or in an exhaled gas of a living being, the device comprising: a radiation source configured to radiate light as a light emission in a wavelength range of lambda1 (λ1)=2.5 μm to lambda2 (λ2)=14.0 μm; an optically reflecting element configured te reflect light, the optically reflecting element being arranged opposite the radiation source; a first detector array comprising a first detector element configured to detect radiation reflected by the optically reflecting element and a first array bandpass filter element arranged at the first detector element and which forms a detection surface for detecting radiation reflected by the optically reflecting element; a second detector array comprising a second detector element configured to detect radiation reflected by the optically reflecting element and a second array bandpass filter element arranged at the second detector element and which forms a detection surface for detecting radiation reflected by the optically reflecting element; a flow channel configured to guide the flow of a gas flow essentially at right angles to a length axis of the light emission; a first light transmission element; a second light transmission element, each of the first light transmission element and the second light transmission element being configured to be optically transparent for the light emission in the wavelength range of lambda1 (λ1)=2.5 μm to lambda2 (λ2)=14.0 μm; a diaphragm element configured to guide a light beam from the radiation source to the detection surface of the first detector array and the detection surface of the second detector array; and a control unit configured to control operation of the radiation source and for detecting signals of the first detector element and the second detector element, wherein: one of the first array bandpass filter element and the second array bandpass filter element is configured to be optically transparent for infrared radiation, which is absorbed by a measured gas, wherein another one of the first array bandpass filter element and the second array bandpass filter element is configured as being optically transparent for infrared radiation which is not absorbed by the measured gas; a reflection surface of the optically reflecting element is arranged at a reflection surface distance (l.sub.3) from the detection surface of the first detector array and the detection surface of the second detector array; a distance (l.sub.F2) of the second light transmission element to the detection surface of the first detector array and the detection surface of the second detector array is related to the reflection surface distance (l.sub.3) according to a relationship: a diaphragm element distance (l.sub.DB) from the detection surface of the first detector array and the detection surface of the second detector array to the diaphragm element is based on ratios according to a relationship: the first light transmission element is arranged as part of a wall of the flow channel; a distance l.sub.F1 of the first light transmission element to the reflection surface of the optically reflecting element in relation to the reflection surface distance (l.sub.3) is according to a relationship: the diaphragm element is arranged at or outside the flow channel with a ratio of a width extension (l.sub.B) of the diaphragm element in relation to a width extension (l.sub.R) of the optically reflecting element according to a relationship: and a ratio for the width extension (l.sub.B) of the diaphragm element in relation to the width extension (l.sub.R) of the optically reflecting element and a width extension of the first detector array and the second detector array (l.sub.D1,2) is according to a relationship: whereby a range of overlap is obtained, in the flow channel for the light emission generated by the radiation source, between the first detector array and the second detector array.
9. A device in accordance with claim 8, wherein: the radiation source is configured as a spotlight or as a light-emitting diode radiating in a punctiform shape with a radiating surface directed toward the optically reflecting element essentially with a width radiation angle of 80° to 170° and is configured for uniform radiation in a direction of the optically reflecting element; and an area of the radiating surface of the radiation source is selected to be in a range of 0.05 mm.sup.2 to 1 mm.sup.2.
10. A device in accordance with claim 8, wherein the optically reflecting element is configured with a surface structure for a uniform distribution of the reflected light, between the first detector array and the second detector array.
11. A device in accordance with claim 8, wherein: the first detector element and the second detector element are arranged at a first distance (l.sub.1) from the length axis in a range of 0.1 mm to 10.0 mm; the first array bandpass filter element and the second array bandpass filter element are arranged at the first detector element and the second detector element at a second distance (l.sub.2) from the length axis, extending between the first detector array and the second detector array in a range of 0.1 mm to 10.0 mm.
12. A device in accordance with claim 8, wherein the first array bandpass filter element and the second array bandpass filter element are configured for optical filtering of infrared light in a transmission range of a wavelength range of 2.5 μm to 14 μm.
13. A device in accordance with claim 8, wherein the first detector element and the second detector element are configured as pyrodetectors, bolometers, semiconductor detectors, thermopiles or thermocouples.
14. A device in accordance with claim 8, wherein: a space area, between the first detector array and the second detector array and the diaphragm element; and/or a space area between the diaphragm element and the second light transmission element; and/or a space area between the radiation source and/or the optically reflecting element and the first light transmission element; and/or a space area between the second light transmission element and one of the first detector array and the second detector array, is filled with an optically transparent material, which has an optical refractive index n>1.
15. A device in accordance with claim 14, wherein the length l.sub.F1, l.sub.F2 and l.sub.DB are physical geometric length extensions or as physical optical length extensions with inclusion of optical refractive indices of optically transparent materials between the diaphragm element and the second light transmission element and/or the diaphragm element and one of the first detector array and the second detector array and/or the radiation source or the optically reflecting element and the first light transmission element and/or the second light transmission element and one of the first detector array and the second detector array.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) In the drawings:
(2) FIG. 1a is a first schematic view of a device for concentration determination;
(3) FIG. 1b is another, second schematic view of a device for concentration determination;
(4) FIG. 2 is an arrangement of a device for concentration determination at a flow channel;
(5) FIG. 3 is another arrangement of a device for concentration determination at a flow channel; and
(6) FIG. 4 is a view of the range of overlap in a device for concentration determination according to FIGS. 1a and 1b.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(7) Referring to the drawings, FIG. 1a shows a first schematic view of a device 1 for determining the concentration of at least one gas component in a breathing gas mixture. The device 1 shown has a radiation source 30 with a radiation element 300. A detector element 50 and a detector element 60 are arranged opposite the radiation source 30 at a vertical (length) distance l.sub.3 33. Bandpass filter elements 51, 61 are arranged at the detector elements 50, 60. The bandpass filter elements 51, 61 are preferably configured as bypass filter elements that are transparent to a predefined wavelength range of the radiation 31 emitted by the radiation source 30. This FIG. 1a shows a coordinate system with vertical (length) reference axis 32 and with a horizontal (width) reference axis 36, to which system reference is made in the description of the positions of the components in relation to one another. Thus, a radiation takes place from the radiation source 30 out of a horizontal plane of radiation 37, the horizontal plane 37 being parallel to the horizontal reference plane 36. A control unit 9 is provided, which is connected to the radiation element 300 by means of control lines 93, 93′. Furthermore, the control unit 9 is connected to the detector element 60 by means of control lines 96, 96′. The control unit 9 is furthermore connected to the detector element 50 by means of control lines 95, 95′. The detector element 50 together with the corresponding filter element 51 forms a detector array 52. The detector element 60 together with the corresponding filter element 61 forms a detector array 62. The detector arrays 52 and 62 together form a detector configuration 40, which functionally forms the device 1 for determining the concentration of a gas component in conjunction with the radiation source 30 and the control unit 9. The arrangement of the detector configuration 40 in relation to the vertical axis 32 and to the horizontal reference axis 36 is determined by distances of the detector arrays 52, 62. The detector array 52 is configured in this FIG. 1a in a parallel arrangement to the horizontal reference axis 36 as well as to the horizontal plane of the radiation 37. A horizontal (width) distance l.sub.1 34 of the detector element 50 to the central axis 32 is obtained in the detector configuration 40. A distance l.sub.1 34′ is obtained for the detector element 60 from the central axis 32 in the detector configuration 40. A distance l.sub.2 35 of the bandpass filter element 51 is obtained from the central axis 32 in the detector configuration 40. Furthermore, a distance l.sub.2 35′ is obtained for the filter element 61 from the central axis 32 in the detector configuration 40. Due to the detector arrays 52, 62 being arranged at right angles in relation to the central axis 32, the distances l.sub.1 34 and l.sub.2 35 between the central axis 32 and the detector element 50, on the one hand, and the filter element 51, on the other hand, are identical.
(8) A flow channel 100, which is arranged between the radiation source 30 and the detector arrays 52, 62 in parallel to the horizontal reference axis 36, is shown in the schematic view of the device 1 for determining the concentration of at least one gas component in a breathing gas mixture. A first transparent light transmission element F1 21 and a second transparent light transmission element F2 22 are arranged opposite each other in walls of the flow channel 100, whereby a radiation 31 is made possible from the radiation source 30 through the flow channel 100.
(9) Extensions or expansions of the components as well as distances of the components in relation to one another are shown in this FIG. 1a in the form of lengths, as they are listed in Tables 2a and 2b.
(10) A distance l.sub.F1 210 between the light transmission element F1 21 and the radiation source 30 is shown.
(11) A distance l.sub.F2 220 between the light transmission element F2 22 and the detector arrays 52, 62 is shown.
(12) A distance l.sub.DB 240 between the diaphragm element B 23 and the detector arrays 52, 62 is shown.
(13) The vertical distance l.sub.3 33 between the radiation source 30 and the detector arrays 52, 62 is shown.
(14) A horizontal extension l.sub.S 388 of the radiation source 30 is shown.
(15) A horizontal extension l.sub.B 230 of an aperture of the diaphragm B 23 is shown.
(16) Horizontal extensions lD1,2 600 of the detector arrays 52, 62 are shown.
(17) The device 1 for determining the concentration of at least one gas component in a breathing gas mixture according to this FIG. 1a is structurally configured such that using the relationships A, B, C, D, E according to Table 3 as the basis for the structural dimensioning, a configuration of a compact arrangement with a range of overlap 65 (FIG. 4) is obtained.
(18) Due to this configuration of the compact arrangement, which is obtained on the basis of the application of the geometric structural conditions shown above by means of the relationships A, B, C, D, E listed above in Table 3 for the first embodiment and on the basis of a distance l.sub.0 38 (FIG. 4) between the two detector arrays 52, 62 in the detector configuration 40, as well as of the distances 34, 34′, 35, 35′ from the vertical central axis 32 of the horizontal extension l.sub.S 388 of the radiation source 30, of the horizontal extension l.sub.B 230 of the aperture of the diaphragm B 23, and of the horizontal extensions lD1,2 600 of the detector arrays 52, 62 in conjunction with the vertical distance l.sub.3 33, the range of overlap 65 (FIG. 4) in the radiation 31 emitted by the radiation source 30 is obtained for the radiation 31 emitted by the radiation source 30 along the vertical distance between the radiation source 30 and the detector configuration 40.
(19) This range of overlap 65 (FIG. 4) is obtained vertically from the plane of the detector arrays 52, 62 in the direction of the radiation source 30. Due to this, the situation is obtained, for example, for gas molecules or condensate (moisture, such as water vapor or water droplets) 400, which are shown in this FIG. 1a, for example, on the central axis 32 in the vicinity of the radiation source 30, in which the radiation 31 of radiation source 30 passes through this gas molecule 400 and it becomes effective as radiation 31 onto both the detector element 50 and onto the detector element 60. It is thus ensured that, for example, moisture (condensate) 400 attenuates the radiation onto both the detector element 50 and onto the detector element 60 in the same manner. This leads to the possibility of eliminating the influence of moisture and impurities from the formation of the ratio of the signals of the detector element 50 and of the detector element 60.
(20) Reference should be made in this description of FIG. 1a to FIG. 4, in which the effects are schematically illustrated in the construction of the device 1 according to the described conditions A, B, C, D, E concerning the range of overlap 65 (FIG. 4) in the radiation 31 in a simplified, graphic form.
(21) The control unit 9 analyzes the signals of the detector elements 50, 60 by means of suitable electronic components (amplifier, analog-to-digital converter, microcontroller) and provides an output signal 99. The output signal 99 is representative here of the signals detected by the detector elements 50, 60 as well as of the ratio of the detected signals and it is also representative of a gas concentration derived from these signals or signal ratio.
(22) FIG. 1b shows another, second schematic view of a device 1′ for determining the concentration of at least one gas component in a breathing gas mixture. Components that are identical in FIG. 1a and in FIG. 1b are designated by the same reference numbers as are the correspondingly equivalent components in FIG. 1a.
(23) FIG. 1b shows with the additional, second schematic view a modified variant of FIG. 1a. Unlike in FIG. 1a, the radiation source 30 is arranged in FIG. 1b on the same side as the optical elements and the detectors. The device 1′ shown has a radiation source 30 (the numbering is missing in FIG. 1b) with a radiation element 300. A detector element 50 and an additional detector element 60 are arranged directly adjacent to the radiation source 30. Bandpass filter elements 51, 61 are arranged at the detector elements 50, 60. A reflector 39, for example, a mirror or plane mirror, is arranged as an optically reflecting element opposite the radiation source 30. The reflector 31 acts as a mirror for the radiation 31 emitted by the radiation source 30 and brings about a reflection of a reflected radiation 31′ towards the bandpass filter elements 51, 61 as well as towards the detector elements 50, 60. The bandpass filter elements 51, 61 are transparent to light in a predefined wavelength range. A coordinate system with vertical reference axes 32 and horizontal reference axes 36 is shown in this FIG. 1b. These axes are used, similarly to their use described in the description of FIG. 1a, as a reference for the position of the components in relation to one another and in space. A control unit 9 is provided, which is connected to the radiation element 300 of the radiation source 30. The arrangement by means of control line 93, 93′ and 96, 96′ as well as 95, 95′ for connecting the control unit 9 to the detector elements 60, 50 corresponds to the arrangement according to FIG. 1a and to the corresponding description, which shall then be used as a reference for this. The detector element 50 forms a detector array 52 together with the corresponding filter element 51. The detector element 60 likewise forms a detector array 62 together with the corresponding filter element 61. These detector arrays 52, 62 form, together with the radiation source 30, a detector configuration 41, which functionally form the device 1′ for determining the concentration of a gas component in conjunction with the control unit 9 and the reflector 39. The arrangement of the detector configuration 41 in reference to the axes 32, 36 is determined by distances of the detector arrays 52, 62. The detector arrays 52, 62 are each configured in this FIG. 1b at right angles to the vertical central axis 32. A horizontal distance l.sub.1 34 is obtained between the detector element 50 and the central axis 32 in the detector configuration 41. A distance l.sub.1 34′ is obtained in the detector configuration 41 for the detector element 60 from the central axis 32. A distance l.sub.2 35 is obtained between the bandpass filter element 51 and the central axis 32 in the detector configuration 41. Due to the detector arrays 52, 62 being arranged at right angles to the central axis 32, the distances l.sub.1 34′ and l.sub.2 35′ from the central axis 32 are identical for the detector element 50 and the filter element 51. Furthermore, a distance l.sub.2 35′ is obtained in the detector configuration 41 between the filter element 61 and the central axis 32. Due to the detector arrays 52, 62 being arranged at right angles to the central axis 32, the distances l.sub.1 34 and l.sub.2 35 of the detector element 50 and the filter element 51 from the central axis 32 are identical.
(24) A flow channel 100′, which is arranged between the reflector 39 and the detector arrays 52, 62 parallel to the horizontal reference axis 36, is shown in the schematic view of the device 1′ for determining the concentration of at least one gas component in a breathing gas mixture. A first transparent light transmission element F1 21 and a second transparent light transmission element F2 22 are arranged opposite each other in walls of the flow channel 100′, as a result of which a radiation 31 is made possible by means of the radiation source 30 and by means of the reflector 39 of reflected radiation 31′ through the flow channel 100′.
(25) Extensions or expansions of the components as well as distances between the components are shown in this FIG. 1b in the form of lengths, as they are listed in Tables 2a and 2b.
(26) A distance l.sub.F1 210 between the light transmission element F1 21 and the reflector 39 is shown.
(27) A distance l.sub.F2 220 between the light transmission element F2 22 and the detector arrays 52, 62 is shown.
(28) A distance l.sub.DB 240 between the diaphragm element B 23 and the detector arrays 52, 62 is shown.
(29) A vertical (length) distance l.sub.3 33′ between the reflector 39 and the detector arrays 52, 62 is shown.
(30) A horizontal (width) extension lR 390 of the reflector 39 is shown.
(31) A horizontal (width) extension l.sub.B 230 of an aperture of the diaphragm B 23 is shown.
(32) Horizontal (width) extensions lD1,2 600 of the detector arrays 52, 62 are shown.
(33) The device 1′ for determining the concentration of at least one gas component in a breathing gas mixture according to FIG. 1b is structurally configured such that using the relationships A, B, C, D′, E′ according to Table 3 as the basis of the structural dimensioning, a configuration of a compact arrangement with a range of overlap 65 (FIG. 4) is obtained.
(34) In conjunction with the vertical distance l.sub.3 33′, the range of overlap 65 (FIG. 4) is obtained for the radiation 31′ reflected from the reflector 39 along the vertical distance between the radiation source 30 and the detector configuration 41 due to the configuration of the compact arrangement, which is obtained on the basis of the application of the geometric structural conditions shown above by means of the relationships A, B, C, D′, E′ listed in Table 3 for the second embodiment and on the basis of a distance l.sub.0 38 (FIG. 4) between the two detector arrays 52, 62 in the detector configuration 41 as well as of the distances 34, 34′, 35, 35′ to the vertical central axis 32, of the horizontal extension l.sub.R 390 of the reflector 39, of the horizontal extension l.sub.B 230 of the aperture of the diaphragm B 23, and of the horizontal extensions lD1,2 600 of the detector arrays 52, 62. This range of overlap 65 (FIG. 4) is obtained vertically from the plane of the detector arrays 52, 62 in the direction of the radiation source 30. The detector arrays 52, 62 are configured in reference to the horizontal reference axis 36, the central axis 32 and to a horizontal plane of the light reflection of the reflector 37′, which reflector is arranged parallel to the horizontal reference axis 36. The range of overlap 65 (FIG. 4), which is obtained on the basis of the detector arrays 52 and 62, causes impurities or condensate, which are present in the reflected radiation 31, for example, in the vicinity of the reflector 39, to influence, i.e., possibly attenuate the radiation to the detector element 50 as well as to the detector element 60 in the same manner. As is described in connection with FIG. 4, this leads to the possibility of eliminating the influence of moisture 400 (FIG. 1a) or impurities from the ratio of the signals of the detector element 50 and of the detector element 60.
(35) Reference should be made in this description to FIG. 1b and FIG. 4, in which the effects are schematically illustrated in the construction of the device 1′ according to the described conditions A, B, C, D′, E′ concerning the range of overlap 65 (FIG. 4) in the reflected radiation 31′ in a simplified graphic form.
(36) Contrary to FIG. 1a, a longer beam path, in the simplest case a doubled beam path is obtained in this FIG. 1b for the path of the radiation 31 towards the reflector 39 and for the path of the reflected radiation 31′ to the detector elements 50, 60. The consequence of this is that the light beams reaching the detector elements 50, 60 have a lower intensity than in FIG. 1a. This leads to a difference concerning the sensitivity of the device 1′ for determining the concentration of a gas component in this FIG. 1b. The analysis of the signals of the detector elements 50, 60 in the control unit 9 takes place by means of suitable electronic components similarly to how it is described in connection with FIG. 1a. The control unit provides an output signal 99, which is representative of the signals of the detector elements 50, 60 or of the ratio of the signals of the detector elements 50, 60. Thus, the output signal 99 provides a gas component derived from the signals on the basis of the detected signals of the detector elements 50, 60 for further processing, for example, in a display unit 94 (FIG. 2).
(37) FIGS. 2 and 3 show arrangements of a device for determining the concentration according to FIGS. 1a, 1b. FIGS. 2, 3 shall be described in a joint description of the figures concerning the common feature they share, but also concerning the differences from one another. Identical components in FIGS. 2, 3 are designated by the same reference numbers as the correspondingly identical components in FIGS. 2, 3. Identical components in FIGS. 2, 3 and in FIGS. 1a, 1b are designated by the same reference numbers as the correspondingly identical components in FIGS. 2, 3 as well as in FIGS. 1a, 1b.
(38) FIG. 2 shows device 1 for determining the concentration of a gas component (FIG. 1b). The flow channel 100′ is configured to feed a flow with a quantity of gas 80 for measurement by means of the device 1′ (FIG. 1b). Detector arrays 52, 62 are shown in conjunction with a radiation source 30, with a radiation element 300 configured as a spotlight 30′ and with a control unit 9. The detector arrays 52, 62 with the radiation source 30 and with the control unit 9 are arranged in a holding element 97, which is coupled with the flow channel 100′. The flow channel 100′ has a first light transmission element F1 21, which forms an assembly unit with a reflector 39 in a wall of the flow channel 100′. The flow channel 100′ has a second light transmission element F2 22, which forms an assembly unit with a diaphragm element 23 in a wall of the flow channel 100′. The light transmission elements F1 21, F2 22 are configured for passing through light that is emitted by the radiation source 30, 30′ and for passing through light reflected by the reflector 39. The light transmission elements F1 21, F2 22 as well as the reflector 39 and the diaphragm element 23 are arranged on the flow channel 100′ by means of sealing elements in order to guarantee the gas-tightness of the flow channel 100′. The mode of operation of the arrangement according to FIG. 2 is as described in connection with FIG. 1b.
(39) Contrary to FIG. 2, FIG. 3 shows a device 1 for determining the concentration of a gas component according to FIG. 1a. The radiation source 30 is arranged opposite two detector arrays 52, 62 at the flow channel 100. The detector arrays 52, 62 with the radiation source 30 and with the control unit 9 are arranged in a holding element 97, which is coupled with the flow channel 100. The detector arrays 52, 62 and the radiation source 30 are arranged opposite each other at a location of the flow channel 100, at which the flow cross section is reduced in the form of a Venturi tube.
(40) The flow channel 100 has a first light transmission element F1 21, which is arranged in a wall of the flow channel 100. The flow channel 100 has a second light transmission element F2 22, which forms an assembly unit with a diaphragm element 23 in a wall of the flow channel 100. The light transmission elements F1 21, F2 22 are configured for passing through light emitted by the radiation source 30. The light transmission elements F1 21, F2 22 as well as the diaphragm element 23 are arranged on the flow channel 100 by means of sealing elements 98 in order to guarantee the gas-tightness of the flow channel 100. It is necessary in this embodiment according to FIG. 3 to provide elements of a control unit 9 from two sides. This makes it possible to operate the detector arrays 52, 62 with the detector elements 50, 60 (FIG. 1a) and to amplify the signal. In addition, the control unit 9 is used to actuate the radiation source 30 and to output the output signal 99.
(41) An output signal 99, which is representative, as was explained above in FIGS. 1a and 1b, of a detected gas concentration, is provided in FIGS. 2, 3.
(42) FIG. 2 shows a medical device 200 as well as a display unit 94 in broken lines each as optional components. These optional components represent exemplary possibilities of sending the output signal 99 for further processing and use.
(43) FIG. 3 does not show these optional components 200, 94, but they shall also be included in the embodiment according to this FIG. 3 based on the inventive idea.
(44) FIG. 4 shows a view 1000 of the range of overlap 65 in devices 1, 1′ for determining the concentration according to FIGS. 1a and 1b. Identical components in FIG. 4 and in FIGS. 1a, 1b, 2, 3 are designated in FIG. 4 by the same reference numbers as the correspondingly identical components in FIGS. 1a, 1b, 2, 3.
(45) The effects are shown in the construction of the device 1 (FIG. 1a) as well as of the device 1′ (FIG. 1b) when observing the conditions A, B, C, D, E or A, B, C, D′, E′ described in Table 3 concerning the range of overlap 65 in the radiation 31 according to FIG. 1a as well as in the reflected radiation 31 according to FIG. 1b. Two detector arrays 52, 62 are shown in a schematic form with a distance l.sub.0 38 between the two detector arrays 52, 62. An optically radiating element or an optically reflecting element configured as a radiation source 30 according to FIG. 1a or configured as a reflector 39 according to FIG. 1b is located opposite the detector arrays 52, 62.
(46) A radiation source needed for a configuration according to FIG. 1b is positioned on a vertical axis 32 as a spotlight 30′ between the two detector arrays 52, 62, comparably to what is shown in FIG. 1b.
(47) It should be noted in this connection that this view according to FIG. 4 is a constellation with the radiation source 30, 30′ and reflector 39 according to the device 1′ (FIG. 1b), wherein the radiation source 30, 30′ and the detector arrays 52, 62 are arranged adjacent to one another, while the constellation with the radiation source 30 according to device 1 (FIG. 1a), in which the radiation source 30 and the detector arrays 52, 62 are arranged opposite each other, does not require an optically reflecting element in the arrangement.
(48) Since the effects on the construction conditions (distances, extensions, expansions) are comparable to the conditions A, B, C, D, E and A, B, C, D′, E′ described in Table 3 concerning the range of overlap 65, this is summarized and shown in this FIG. 4 in the view 1000. A flow channel 100, 100′ with a first transparent light transmission element F1 21 and with a second transparent light transmission element F2 22 and with a diaphragm element 23, which are arranged in a wall of the flow channel 100, 100′, is shown between the two detector arrays 52, 62 and the optically radiating element 30 or the optically reflecting element 39. The vertical arrangement of the first transparent light transmission element F1 21 and of the second transparent light transmission element F2 22, of the diaphragm element 23, of the detector arrays 52, 62 and of the optically radiating element 30 or of the optically reflecting element 39 is shown graphically in this FIG. 4 under conditions that arise from the application of the conditions A, B, C, D, E and A, B, C, D′, E′. The range of overlap 65, which is obtained in the flow channel 100, 100′ for radiation 31 from the radiation source 30 or for reflected radiation 31 to the two detector arrays 52, 62, can therefore be extrapolated concerning a relative extension of the range of overlap 65 in the flow channel 100, 100′. The greater the extension of the range of overlap 65 in the flow channel 100, 100′, the more effectively is it possible to eliminate the influence of moisture and impurities by forming the ratio between the two detector elements 50, 60 (FIGS. 1a, 1b) of the first detector array and the second detector array 52, 62.
(49) While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
APPENDIX
List of Reference Designations
(50) 1, 1′ Device for determining the concentration of a gas component 9 Control unit 21 First light transmission element, window element (F1) 22 Second light transmission element, window element (F2) 23 Diaphragm element (B) 30 Radiation source 30′ Radiation source 30 configured as a spotlight 31 Radiation 31′ Reflected radiation 32 Vertical (length) axis, central axis, vertical reference axis, vertical axis 33 l.sub.3, l.sub.3′ vertical (length) distance 34 l.sub.1 distance of the detector element 50 from the central axis 32 34′ l.sub.1 distance of the detector element 60 from the central axis 32 35 l.sub.2 distance of the filter element 51 from the central axis 32 35′ l.sub.2 distance of the filter element 61 from the central axis 32 36 Horizontal (width) reference axis 37 Horizontal (width) plane of radiation 37′ Horizontal (width) plane of light reflection 38 l.sub.0 distance between the detector elements 50, 60 39 Optically reflecting element, reflector element Reflector, mirror element 40 Detector configuration 41 Detector configuration, reflective 50 Detector element 51 Bandpass filter element 52 Detector array 60 Detector element 61 Bandpass filter element 62 Detector array 65 Range of overlap 80 Quantity of gas, gas concentration 93, 93′ Control line to the radiation element 300 94 Display unit 95, 95′ Data line, signal line 96, 96′ Data line, signal line 97 Holding element 98 Sealing elements 99 Output signal 100, 100′ Flow channel 200 Medical device, ventilator, anesthesia apparatus 210 Distance l.sub.F1 between light transmission element F1 and radiation source 220 Distance l.sub.F2 between light transmission element F2 and detector array 230 Horizontal extension l.sub.B (width, length, diameter) of the diaphragm element (B) 240 Distance l.sub.DB between diaphragm element and detector array 300 Radiation element (diaphragm, coil) 388 Horizontal extension l.sub.S (width, length, diameter) of the radiation source 390 Horizontal extension l.sub.R (width, length, diameter) of the optically reflecting element, reflection element 400 Gas molecule, moisture, condensate 600 Respective horizontal extension lD1,2 (width, length, diameter) of the two detector elements 601 Space area between detector array and diaphragm element B 602 Space area between diaphragm element and second light transmission element F2 603 Space area between detector array and second light transmission element F2 604 Space area between first light transmission element F1 and radiation source 604′ Space area between first light transmission element F1 and reflector element 1000 View of the range of overlap 65
