The optical assay device and method of gasTechnical field
The present invention relates to photoelectric analysis, in particular to new type light source and should the optical assay device of gas of light source, sideMethod.
Background technique
In gas sensor, the output light of diode laser is high divergence, it is therefore desirable to use collimating opticsElement, such as collimation lens.And the introducing meeting of collimation lens is so that generate interference between laser and lens: what laser issuedThe laser for impinging perpendicularly on lens rear surface has part and is reflected back laser, reflects in the front window of laser, againLens rear surface is impinged perpendicularly on, the emergent light of front and back twice will form an interference.In the process of measurement gas absorption signalIn, interfere the striped of formation that will greatly reduce gas detection limit, it is therefore desirable to strongly avoid or eliminate.
The method that tradition eliminates optical interference noise between collimation lens and laser has:
1. lens plate anti-reflection film, plating anti-reflection film can only reduce interference strength to a certain extent, can not inhibit light wellNoise is learned, and the transmitance of bloomed lens can be reduced with daily wiping and mirror surface pollution；
2. lens and optical axis are angled.When the angle of lens axis and optical axis is smaller, the suppression of optical interference noiseAbility processed is poor；When lens and larger optical axis included angle, very serious aberration will be present, beam collimation effect is poor.
Summary of the invention
To solve the deficiency in above-mentioned prior art, it is low, at low cost new that the present invention provides a kind of optical noisesType light source.
The purpose of the present invention is what is be achieved through the following technical solutions:
A kind of new type light source, the new type light source include:
Illuminator, the illuminator are fixed on bracket；
First support, the first support is for carrying the illuminator；
Light collimation device, the light collimation device are fixed in the optical path of the emergent light of the illuminator, and collimation is described outPenetrate light；Angle between the axis of the light collimation device and the optical axis of the emergent light is acute angle；
Rotating member, the light collimation device are fixed on the rotating member；
Second support, the rotating member are rotatably arranged in the second support；
Motor, the motor is for driving the rotating member and light collimation device to rotate.
According to above-mentioned new type light source, it is preferable that the acute angle is less than 30 degree.
According to above-mentioned new type light source, it is preferable that the light collimation device is plate-convex lens, and the emergent light is successively wornCross plane and the convex surface of the lens.
According to above-mentioned new type light source, it is preferable that the first support is the sleeve with radial component and axial component,The illuminator is fixed on the center of the radial component.
According to above-mentioned new type light source, it is preferable that the rotating member is bearing, the portion of the axial component of the first supportIt is allocated as second support, the outer ring of the bearing is fixed in the second support.
According to above-mentioned new type light source, optionally, the new type light source further comprises:
Fixing piece, the light collimation device are arranged on the fixing piece, and the fixing piece is arranged on the rotating member；The motor drives the fixing piece rotation.
According to above-mentioned new type light source, it is preferable that the fixing piece is sleeve.
According to above-mentioned new type light source, it is preferable that the illuminator is laser.
The object of the invention is also to provide a kind of gases using above-mentioned new type light source of the high and low cost of detection accuracyOptical assay device, which is achieved by the following technical programs:
The optical assay device of gas, the optical assay device include light source, detector and analytical unit；
The light source uses above-mentioned new type light source；
The analytical unit includes averager, computing module, and the averager comes for the average detector transmissionSpectroscopic data entrained by electric signal send the computing module later；After the computing module is handled averagely using spectral techniqueElectric signal.
The object of the invention is also to provide a kind of high gases using above-mentioned optical assay device of detection accuracyAnalysis method, the goal of the invention are achieved by the following technical programs:
According to the analysis method of the gas of above-mentioned optical assay device, the analysis method the following steps are included:
(A1) the light collimation device collimation that the measurement light that illuminator issues is rotated；
(A2) the measurement light emission after collimating enters in region to be measured, interacts under test gas；
(A3) the measurement light for projecting the region to be measured is converted into electric signal, and send analysis module；
(A4) averager is averaged the electric signal, computing module using spectral technique handle it is average after electric signal, knowThe parameter of under test gas.
Compared with prior art, the device have the advantages that are as follows:
1. the angle between the axis of light collimation device and the optical axis of illuminator emergent light is acute angle, reduce to a certain extentOptical noise, but also reduce collimating effect；But by rotating the light collimation device,
So that every time measurement when generate optical interference condition it is different, it is complementary relevant between optical interference noise, pass through byThe spectroscopic data multiple averaging that the optical signal of measurement carries, inhibited optical interference noise with not only having can dramatically, but also significantly reduceThe light collimation device bring collimating effect difference bring adverse effect being obliquely installed；
Anti-reflection film is plated on light collimation device surface, further reduced optical noise；
The small above-mentioned light source of optical noise helps to improve the analysis precision of the laser gas analyzer using the light source；
2. each device is cheap and easy to get, so that entire cost of light source is low.
Detailed description of the invention
Referring to attached drawing, the disclosure of the present invention will become more readily understood.Skilled addressee readily understands that: thisIt is only used to illustrate the technical scheme of the present invention for a little attached drawings, and is not intended to limit the scope of protection of the present invention.In figure:
Fig. 1 is the structure diagram of according to embodiments of the present invention 1 new type light source；
Fig. 2 is the structure diagram of according to embodiments of the present invention 2 new type light source.
Specific embodiment
Fig. 1-2 and following description describe optional embodiments of the invention to instruct how those skilled in the art implementIt is of the invention with reproducing.In order to teach the technical scheme of the invention, it has simplified or omitted some conventional aspects.Those skilled in the artIt should be understood that the variation or replacement from these embodiments will within the scope of the invention.Those skilled in the art should understand thatThe following features can be combined in various ways to form multiple variations of the present invention.As a result, the invention is not limited to it is following canEmbodiment is selected, and is only limited by the claims and their equivalents.
Embodiment 1:
Fig. 1 schematically illustrates the structure diagram of the new type light source of the present embodiment, as shown in Figure 1, the new type light sourceInclude:
Illuminator 11, for emitting monochromatic light；The illuminator is fixed in first support；
First support 21, such as circular sleeve, mounting plate, for carrying the illuminator, bracket is formed with the bracketThe optical channel passed through suitable for the illuminator emergent light；
Light collimation device 81, such as plate-convex lens, the light collimation device is fixed on the optical path of the emergent light of the illuminatorOn, collimate the emergent light；Angle between the axis of the light collimation device and the optical axis of the emergent light is acute angle, such as 2 degree,10 degree, 25 degree etc., but it is no more than 30 degree；
Rotating member 31, the light collimation device are fixed on the rotating member；
Second support 61, the rotating member are rotatably arranged in the second support；
Motor 51, the motor is for driving the rotating member and light collimation device to rotate.
Embodiment 2:
The laser gas analyzer of the embodiment of the present invention, the laser gas analyzer include:
New type light source, as shown in Fig. 2, the new type light source includes:
Illuminator 11 selects semiconductor laser with tunable；
First support 21 is fixed on the diameter using the circular sleeve with radial component, axial component, the illuminatorTo the center of part；The part 22 of axial component is used as second support；
Rotating member 31 uses bearing, and bearing outer ring is fixed in the second support namely the inside of the axial component；
Fixing piece 41, fixing piece use sleeve, are fixed on rotating member, i.e., on the inner ring of bearing；
Light collimation device 81 uses plate-convex lens, and lens are fixed in the fixing piece, and the axis and laser of lens are sent outThe angle of optical axis of measurement light out is acute angle, and such as 5 degree, lens plating has the anti-reflection film passed through convenient for the measurement light, convex surfaceBack to the laser；
Motor 51, such as the motor driven by electricity, gas, magnetic, hydraulic mode make for driving the fixing piece to rotateLight collimation device rotation is obtained, but the displacement on measurement light optical path direction does not occur；
Detector, the detector are used to be converted to by the measurement light of collimation to interact under test gasElectric signal, and send analytical unit；
Analytical unit, the analytical unit include: averager, computing module, and the averager is used for the average telecommunicationsNumber spectroscopic data carried, computing module using spectral analysis technique handle it is average after spectroscopic data, to know gas to be measuredThe parameter of body, such as gas content, flow velocity.
The analysis method of the gas of the embodiment of the present invention, i.e., the course of work of above-mentioned analyzer, the analysis method includeFollowing steps:
(A1) the light collimation device collimation that the measurement light that laser issues is rotated；
(A2) the measurement light emission after collimating enters in region to be measured, interacts under test gas；
(A3) the measurement light for projecting the region to be measured is converted into electric signal, and send analysis module；
(A4) spectroscopic data that the average electric signal of averager carries, computing module are handled flat using absorption spectroscopy techniquesElectric signal after knows the concentration of under test gas.
Embodiment 3:
The laser gas analyzer of the embodiment of the present invention, as shown in Figure 1, as different from Example 2:
1. not using fixing piece, light collimation device is directly anchored on the inner ring of bearing, and motor directly drives inner ring and turnsIt is dynamic, frictional force drives inner ring is utilized by the driving wheel of motor；
2. second support is separately provided, the outer ring of the bearing is fixed in the second support；The survey that laser issuesIt measures light and passes through light collimation device, and the angle between optical axis and the axis of light collimation device is acute angle, such as 10 degree, 15 degree, 20 degree, 30Degree etc..
Above-described embodiment is only that illustratively to give illuminator be laser, can also be other illuminators certainly, such asLED etc..