CN100468046C - Multi-gas sensing device - Google Patents
Multi-gas sensing device Download PDFInfo
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- CN100468046C CN100468046C CNB2005101153876A CN200510115387A CN100468046C CN 100468046 C CN100468046 C CN 100468046C CN B2005101153876 A CNB2005101153876 A CN B2005101153876A CN 200510115387 A CN200510115387 A CN 200510115387A CN 100468046 C CN100468046 C CN 100468046C
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Abstract
The invention discloses a multi-gas sensing device, using the planar waveguide circuit to construct the multi-gas sensing platform with sensing channel and reference channel, substantially thin gas sensor structure, to increase gas sensor accuracy and long-term stability, and reduce the response time. It can be widely used in factory work site's safety monitoring, staff security monitoring, factory disaster warning, restricted regional security monitoring, pipeline leak investigation, environmental steam locomotive emission monitoring, and home environment quality monitoring.
Description
Technical field
The present invention relates to a kind of gas measuring device, particularly a kind ofly utilize the planar lightwave circuit construction to have sense channel and reference channel so that the multi-gas sensing device of at least a gas of sensing to be provided.
Background technology
The qualitative and quantitative analysis of many gases has a wide range of applications in fields such as environmental monitoring, home alarm, chemical industry control, greenhouse control and aviations.The using gases sensor carries out the qualitative, quantitative research of many gases, can significantly reduce the measurement cost, reduces measuring period, and can realize real-time control measurement.But because present gas sensor, the problem of cross-sensitivity (Cross sensitivity) as conductor oxidate formula, metal oxide formula, electric chemical formula or solid electrolyte formula ubiquity, and cross-sensitivity can significantly reduce the repeatability and the reliability of measurement, and make sensor can't accurately judge the concentration of indivedual target gases, realize many gas sensings though can utilize the different gas sensor of a plurality of sensitivitys to form sensor groups, but still can't eliminate the cross-sensitivity of sensor gas with various.And utilizing gas with various the principle of different absorption characteristics to be arranged for infrared light, designed optical gas sensor is because of no cross-sensitivity problem, so extremely be fit to be used for realizing designing and developing of many gas sensors.Existing optical gas sensor causes understanding the increase because of package detection component quantity, and the volume of sensor significantly being increased when realizing many gas sensings because of being subjected to the restriction on traditional cavity body structure, and cost of manufacture also improves relatively.Therefore, optical gas sensor only carries out the sensing design at pure gas mostly at present, and the environment for there being simultaneously multiple harmful gases does not possess adaptive sensing function.
With reference to figure 1, be traditional optics list gas sensor, the structure of this optics list gas sensor includes infrared light supply 10, reference light source 11, cavity 12, beam split filter plate 13 and inspection optical diode 14.By infrared light supply 10 light with particular range of wavelengths that sends, can reflect in cavity 12 inside and transmit, in this process, the light of a certain specific wavelength can penetrate beam split filter plate 13, and tested optical diode 14 receives, its principle is to utilize the light of this specific wavelength by the variation of light intensity that is produced before and after the gas absorption to be measured, comes sensing gaseous species to be measured and concentration.And the light that reference light source 11 is sent can be by gas absorption to be measured, and therefore, its light intensity value can be used as signal initial value or reference value.In the design of general gas sensor, the main function of reference light source is to be used for eliminating because of the signal that factor caused erroneous judgements such as the variation of environment temperature pressure, material behavior change and detection light source deteriorations.
In addition, United States Patent (USP) notification number 6067840 disclosed technology, its reference light source adheres to different sources separately with detection light source.And for example, United States Patent (USP) notification number 6469303,6392234,5610400 and 5550375 disclosed technology are the detection technology of single gas.
Comprehensive above-mentioned known technology framework exists following four main shortcomings:
1. reference light source and detection light source (infrared light supply 10) adhere to separate sources separately.When reference light source and detection light source when deterioration appears in different time points, will make signal initial value (no gas reaction) and signal response value (gas reaction is arranged) be difficult to distinguish.If reference light source and detection light source belong to same source, its reference light source can be consistent with detection light source deterioration time point, and then signal initial value and signal response value will be easy to distinguish out.
2. the light path path walked of reference light source and detection light source is different.When changing appears in environment temperature, pressure or material behavior, can cause air and material refraction index changing, and the light path path also can change, if reference light source is different with the light path path that detection light source is walked, can make the signal initial value be vulnerable to the influence of environment temperature, pressure or changes in material properties, and reduce the accuracy and the long-time stability of sensor.
3. can't realize many gas sensings.
4. slimming gas sensor significantly.
In sum, be starved of a kind of multi-gas sensing device and solve problem in the known technology.
Summary of the invention
The object of the present invention is to provide a kind of many gas sensings platform, the cross-sensitivity in the time that many gas detection can being eliminated.In addition, the sense channel and the reference channel that utilize planar lightwave circuit to design, the signal erroneous judgement that is caused because of light source deterioration, variation of ambient temperature, pressure variation and waveguide material characteristic variations be can eliminate, and then the accuracy and the long-time stability of sensor improved.And the application by planar lightwave circuit, significantly slimming gas sensor.
To achieve these goals, the invention provides a kind of multi-gas sensing device, it comprises an illuminator, a planar lightwave circuit and at least one device for testing light.This illuminator can be launched a flashlight.This planar lightwave circuit, the one front end couples mutually with this illuminator, this planar lightwave circuit also has a sense channel and a reference channel, this sense channel and this reference channel have at least one open region and at least one end respectively, and this planar lightwave circuit can receive this flashlight to form a sensor light signal and a reference optical signal respectively.This at least one device for testing light, it is arranged at this sense channel and the set at least one end of this reference channel, converts this sensor light signal and this reference optical signal to electric signal.
Preferably, this illuminator may be selected to be emitting laser transistor, surface emitting laser transistor or light emitting diode on one side.
Preferably, the open region of this sense channel has identical spacing with the open region of this reference channel.This sense channel has identical length with this reference channel.
Preferably, this multi-gas sensing device also has at least one spacer, covers around at least one open region of this reference channel.
Preferably, also has a filter plate between the set at least one end of this device for testing light and this sense channel and this reference channel.
Preferably, this multi-gas sensing device also includes a substrate, is used for carrying this illuminator, this planar lightwave circuit and this device for testing light, and wherein this planar lightwave circuit directly is produced on the surface of this substrate.Wherein this substrate may be selected to be semiconductor material, a macromolecular material or a metal material.
Preferably, this multi-gas sensing device also includes and is used for isolating a dust and a dust barrier film dirty and that allow gas to be measured to pass through.
Preferably, this multi-gas sensing device also includes a control circuit, and this control circuit and this illuminator and this device for testing light connect and compose gas sensor.
To achieve these goals, the present invention also provides a kind of multi-gas sensing device, and it comprises several illuminators, several planar lightwave circuits and several device for testing light.These several illuminators can be launched a flashlight.These several planar lightwave circuits, its front end couples mutually with these several illuminators respectively, this planar lightwave circuit also has a sense channel and a reference channel, this sense channel and this reference channel have at least one open region and at least one end respectively, and this planar lightwave circuit can receive this flashlight and form a sensor light signal and a reference optical signal respectively.These several device for testing light, it is arranged at this sense channel and the set at least one end of this reference channel respectively, converts this sensor light signal and this reference optical signal to electric signal.
Preferably, the signal light wavelength launched of wantonly two these adjacent illuminators may be selected to be identical wavelength or wavelength inequality.
Preferably, also include illuminator in the middle of between this adjacent illuminator, this centre illuminator is communicated with adjacent this planar lightwave circuit with lightwave circuit.The signal light wavelength that this centre illuminator is sent may be selected to be identical wavelength or wavelength inequality with the signal light wavelength that this adjacent illuminator is launched.
Following conjunction with figs. and specific embodiment elaborate to feature of the present invention, but not as a limitation of the invention.
Description of drawings
Fig. 1 is the optics list gas sensor synoptic diagram of known technology;
Fig. 2 A is the preferred embodiment synoptic diagram of multi-gas sensing device of the present invention;
Fig. 2 B is the isolated area synoptic diagram of multi-gas sensing device of the present invention;
Fig. 3 A is another preferred embodiment synoptic diagram of sense channel opening of the present invention;
Fig. 3 B is another preferred embodiment synoptic diagram of reference channel opening of the present invention;
Fig. 4 is another preferred embodiment schematic top plan view of multi-gas sensing device of the present invention.
Wherein, Reference numeral:
The single gas sensor of 1-
The 10-infrared light supply
The 11-reference light source
The 12-cavity
13-beam split filter plate
14-examines optical diode
The many gas sensors of 2-
The 20-substrate
The 21-illuminator
The 22-planar lightwave circuit
The 221-sense channel
The 2210-open region
The 2211-end
2212,2213,2214-Waveguide branching
The 222-reference channel
The 2220-open region
The 2221-spacer
The 2222-spacing block
The 2223-end
2224,2225,2226-Waveguide branching
The 223-front end
The 23-filter plate
The 24-device for testing light
The many gas sensors of 3-
The 30-substrate
31-first illuminator
32-second illuminator
33-the 3rd illuminator
34-first planar lightwave circuit
The 341-sense channel
The 3410-open region
The 342-reference channel
The 3420-spacer
35-second planar lightwave circuit
The 351-sense channel
The 3510-open region
The 352-reference channel
The 3520-spacer
36-the 3rd planar lightwave circuit
361-difference waveguide line
371,372,373,374-filter plate
381,382,383,384-device for testing light
Embodiment
Please refer to Fig. 2 A, this figure is the preferred embodiment synoptic diagram of multi-gas sensing device of the present invention.This embodiment is used for realizing single gas sensing, and this sensing apparatus 2 is formed on the substrate 20.The material of this substrate 20 is semiconductor material, macromolecular material, metal material or flexible material.This sensing apparatus 2 includes an illuminator 21, a planar lightwave circuit 22, a filter plate 23 and at least one device for testing light 24.The front end 223 of this planar lightwave circuit 22 couples mutually with this illuminator 21, to receive the detected light that this illuminator 21 is sent.This illuminator 21 can be limit emitting laser transistor, surface emitting laser transistor or light emitting diode (LED), and the selection of optical wavelength is decided by gaseous species to be measured.
This planar lightwave circuit 22 also has a sense channel 221 and a reference channel 222.This sense channel 221 is divided into two Waveguide branchings 2212,2213, respectively has an open region 2210 on each Waveguide branching 2212,2213, and this two Waveguide branching 2212,2213 is intersection unification again after open region 2210.This sense channel 221 also has at least one terminal 2211, and these end 2211 places are provided with this filter plate 23 respectively, also is provided with this device for testing light 24 after this filter plate 23.In the present embodiment, the quantity of this Waveguide branching 2212,2213 can be set according to circumstances, is not limited to the quantity of present embodiment branch, is to be to increase the area that detected light contacts with gas as for the purpose of Waveguide branching, so that measured accurately.As shown in Figure 3A, this Waveguide branching 2212,2213,2214 is three.
Please refer to Fig. 2 A and Fig. 2 B, wherein Fig. 2 B is the isolated area synoptic diagram of multi-gas sensing device of the present invention.This reference channel 222 is divided into two Waveguide branchings 2224,2225, respectively has an open region 2220 (shown in Fig. 2 B) on each Waveguide branching 2224,2225, and this two Waveguide branching 2224,2225 is intersection unification again after open region 2220.In the present embodiment, the open region 2220 of this reference channel 222 has identical spacing with the open region 2210 of this sense channel 221, and the length of this reference channel 222 is identical with the length of this sense channel 221.
The purpose that this reference channel 222 is provided with is to obtain a relative datum value of measurement, and this reference value to measure employed gas be air.Please refer to Fig. 2 B, mix with gas to be measured, therefore around this open region 2220, block, above this open region 2220, cover a spacer 2221 then, to reach the purpose of air-isolation and gas to be measured with two spacing blocks 2222 for fear of air.This reference channel 222 also has at least one terminal 2223, and these end 2223 places are provided with this filter plate 23, also is provided with this device for testing light 24 after this filter plate 23.This illuminator 21 and this device for testing light 24 are connected to a control circuit, constitute gas sensor, these illuminator 21 transmitting illuminants of this control circuit may command, and handle the electric signal that this device for testing light 24 produces.In the present embodiment, the quantity of this Waveguide branching 2224,2225 can be set according to circumstances, is not limited to the quantity of present embodiment branch, is to increase the area that detected light contacts with gas as for the purpose of Waveguide branching, to be measured accurately.Shown in Fig. 3 B, this Waveguide branching 2224,2225,2226 is three.
Next the method for operation of this multi-gas sensing device 2 is described, the light that is sent by illuminator 20 can be coupled into front end 223, and by planar lightwave circuit 22 leaded lights and beam split, enter sense channel 221 and reference channel 222 respectively, the light that enters sense channel 221 can contact with gas to be measured at open region 2210, this light intensity can be because of being changed by gas absorption, penetrates filter plate 23 at last and enter device for testing light 24, and produce response signal.And enter the light of reference channel 222, and because of being subjected to the obstruct of spacer 2221, can not contacting with gas to be measured at open region 2220, this light intensity can remain unchanged, and penetrates filter plate 23 at last and enters device for testing light 24, and produce reference signal.Above-mentioned filter plate 23 mainly is to be used for other flashlight or parasitic light outside the isolation detection light source, and the main function of device for testing light 24 is to convert light signal to electric signal.In addition, pollute open region for fear of the dust of external environment condition or spot and influenced the precision of sensing, also can provide a dust barrier film to isolate this multi-gas sensing device 2 and dust or dirtyly contact and allow gas to be measured to pass through.
Please refer to Fig. 4, this figure is another preferred embodiment schematic top plan view of multi-gas sensing device of the present invention.This multi-gas sensing device 3 is formed on the substrate 30, is mainly used to realize three gas sensings, and its structure is the framework based on Fig. 2 A basically, only is the difference line that has expanded planar lightwave circuit.This device 3 has one first planar lightwave circuit 34, one second planar lightwave circuit 35 and one the 3rd planar lightwave circuit 36.The front end of this first planar lightwave circuit 34 and one first illuminator 31 couple, and the front end of this second planar lightwave circuit 35 and one the 3rd illuminator 33 couple, and the front end of the 3rd planar lightwave circuit 36 and one second illuminator 32 couple.Wherein, the material of this substrate 30 is semiconductor material, macromolecular material, metal material or flexible material, and the detected light that first illuminator 31, second illuminator 32 and the 3rd illuminator 33 can be launched different wave length, and may be selected to be limit emitting laser transistor, surface emitting laser transistor or light emitting diode (LED).As for the selection of the detected light wavelength that illuminator sent, decide by gaseous species to be measured.
The 3rd planar lightwave circuit 36 couples with this first planar lightwave circuit 34 and this second planar lightwave circuit 35 respectively with two difference waveguide lines 361 and is communicated with.This first planar lightwave circuit 34 is identical with these second lightwave circuit, 35 structures, has a sense channel 341,351 and a reference channel 342,352 respectively.This sense channel 341,351 is divided into two Waveguide branchings, respectively has an open region 3410,3510 on each Waveguide branching, and this two Waveguide branching is intersection unification again after open region 3410,3510.This sense channel 341,351 also has at least one end, and this end is provided with a filter plate 371,373, also is provided with a device for testing light 381,383 after this filter plate 371,373.
This reference channel 342,352 is divided into two Waveguide branchings, respectively has an open region on each Waveguide branching, and this two Waveguide branching is intersection unification again after open region.The top of this open region covers a spacer 3420,3520, is used for the air in the open region and to be measured gas-insulated.This reference channel 342,352 also has at least one end, and this end is provided with a filter plate 372,374, also is provided with a device for testing light 382,384 after this filter plate.As for the principle of measuring, identical with above-mentioned Fig. 2 A do not repeat them here.
By the utilization of suitable planar lightwave circuit, the present invention has following advantage: (1) is the slimming gas sensor significantly.(2) can realize many gas sensings, the extendibility height of its amount of gas to be measured.(3) signal response time is short.(4) accuracy and long-time stability height.
The above is preferred embodiment of the present invention only, is not to be used for limiting the scope of the invention.For example, the front end of this planar lightwave circuit, sense channel, reference channel and terminal quantity can reduce arbitrarily or increase.The quantity of this illuminator and this device for testing light can be according to the variation of the front end of this planar lightwave circuit, sense channel, reference channel and terminal quantity, and elasticity increases or reduce.
Certainly; the present invention also can have other various embodiments; under the situation that does not deviate from spirit of the present invention and essence thereof; those of ordinary skill in the art can make various corresponding changes and distortion according to the present invention, but these corresponding changes and distortion all should belong to the protection domain of the appended claim of the present invention.
Claims (24)
1, a kind of multi-gas sensing device is characterized in that, comprising:
One illuminator can be launched a flashlight;
One planar lightwave circuit, its front end couples mutually with this illuminator, this planar lightwave circuit also has a sense channel and a reference channel, this sense channel and this reference channel have at least one open region and at least one end respectively, this planar lightwave circuit can receive this flashlight, to form a sensor light signal and a reference optical signal respectively; And
At least one device for testing light is arranged at the set at least one end of this sense channel and this reference channel, is used for converting this sensor light signal and this reference optical signal to electric signal.
2, multi-gas sensing device according to claim 1 is characterized in that, this illuminator may be selected to be emitting laser transistor, surface emitting laser transistor or light emitting diode on one side.
3, multi-gas sensing device according to claim 1 is characterized in that, the open region of this sense channel has identical spacing with the open region of this reference channel.
4, multi-gas sensing device according to claim 1 is characterized in that, also has at least one spacer and is covered in around at least one open region of this reference channel.
5, multi-gas sensing device according to claim 1 is characterized in that, this sense channel has identical length with this reference channel.
6, multi-gas sensing device according to claim 1 is characterized in that, also has a filter plate between the set at least one end of this device for testing light and this sense channel and this reference channel.
7, multi-gas sensing device according to claim 1 is characterized in that, also includes a substrate, is used for carrying this illuminator, this planar lightwave circuit and this device for testing light, and wherein this planar lightwave circuit directly is made in the surface of this substrate.
8, multi-gas sensing device according to claim 7 is characterized in that, this substrate may be selected to be semiconductor material, a macromolecular material or a metal material.
9, multi-gas sensing device according to claim 1 is characterized in that, also includes to isolate a dust and a dust barrier film dirty and that allow gas to be measured to pass through.
10, multi-gas sensing device according to claim 1 is characterized in that, also includes a control circuit, and this control circuit is connected with this illuminator and this device for testing light and constitutes gas sensor.
11, a kind of multi-gas sensing device is characterized in that, comprising:
A plurality of illuminators, each illuminator can be launched a flashlight;
A plurality of planar lightwave circuits, its front end couples mutually with these a plurality of illuminators respectively, each planar lightwave circuit also has a sense channel and a reference channel, this sense channel and this reference channel have at least one open region and at least one end respectively, and each planar lightwave circuit can receive this flashlight to form a sensor light signal and a reference optical signal respectively; And
A plurality of device for testing light, it is arranged at this sense channel and the set at least one end of this reference channel respectively, is used for converting this sensor light signal and this reference optical signal to electric signal.
12, multi-gas sensing device according to claim 11 is characterized in that, the signal light wavelength that wantonly two these adjacent illuminators are launched may be selected to be identical wavelength or wavelength inequality.
13, multi-gas sensing device according to claim 11 is characterized in that, also includes illuminator in the middle of between this adjacent illuminator, and this centre illuminator is communicated with adjacent this planar lightwave circuit by lightwave circuit.
14, multi-gas sensing device according to claim 13 is characterized in that, the signal light wavelength that this centre illuminator is sent may be selected to be identical wavelength or wavelength inequality with the signal light wavelength that this adjacent illuminator is launched.
15, multi-gas sensing device according to claim 13 is characterized in that, this centre illuminator may be selected to be emitting laser transistor, surface emitting laser transistor or light emitting diode on one side.
16, multi-gas sensing device according to claim 11 is characterized in that, this illuminator may be selected to be emitting laser transistor, surface emitting laser transistor or light emitting diode on one side.
17, multi-gas sensing device according to claim 11 is characterized in that, the open region of this sense channel has identical spacing with the open region of this reference channel.
18, multi-gas sensing device according to claim 11 is characterized in that, also has at least one spacer and is covered in around at least one open region of this reference channel.
19, multi-gas sensing device according to claim 11 is characterized in that, this sense channel has identical length with this reference channel.
20, multi-gas sensing device according to claim 11 is characterized in that, also has a filter plate between the set end of this device for testing light and this sense channel and this reference channel.
21, multi-gas sensing device according to claim 11, it is characterized in that, also include a substrate, be used for carrying these a plurality of illuminators, these a plurality of planar lightwave circuits and this a plurality of device for testing light, wherein these a plurality of planar lightwave circuits directly are made in the surface of this substrate.
22, multi-gas sensing device according to claim 21 is characterized in that, this substrate may be selected to be semiconductor material, a macromolecular material or a metal material.
23, multi-gas sensing device according to claim 11 is characterized in that, also includes to isolate a dust and a dust barrier film dirty and that allow gas to be measured to pass through.
24, multi-gas sensing device according to claim 11 is characterized in that, also includes a control circuit, and this control circuit is connected with this illuminator and this device for testing light and constitutes gas sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005101153876A CN100468046C (en) | 2005-11-16 | 2005-11-16 | Multi-gas sensing device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005101153876A CN100468046C (en) | 2005-11-16 | 2005-11-16 | Multi-gas sensing device |
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| CN1967211A CN1967211A (en) | 2007-05-23 |
| CN100468046C true CN100468046C (en) | 2009-03-11 |
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| CNB2005101153876A Expired - Fee Related CN100468046C (en) | 2005-11-16 | 2005-11-16 | Multi-gas sensing device |
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| CN105699294B (en) * | 2016-02-29 | 2018-11-02 | 中国工程物理研究院材料研究所 | A kind of micronano optical sensing system of achievable multiple gases measurement of concetration |
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