CN205562386U - Nature atmospheric aerosol muller matrix automatic measuring device - Google Patents

Abstract

The utility model discloses a nature atmospheric aerosol muller matrix automatic measuring device, the device mainly comprise with the data processing unit with measuring unit, data collection and control unit gas pretreatment unit, light source cell, light radiation unit, scattered light collection. The utility model discloses except that measuring the angle of scattering by mechanical servo control, the whole electricity of realizing of all the other component parameters are transferred, and the measuring speed is showing and promotes, the whole solidification of optical component, and the measurement process does not relate to the increase or the reduction of components and parts, and measurement procedure simplifies greatly, can provide accurate natural atmospheric aerosol scattering parameter for the radiative transfer simulation, also provides the infrastest data of accuracy for atmosphere ocean remote sensing, climatology research.

Description

Natural atmosphere aerosol Muller matrix self-operated measuring unit

Technical field

This utility model belongs to meteorological observation field, relates to a kind of natural atmosphere aerosol Muller matrix and automatically measures dress Put.

Background technology

Aerocolloidal light scattering characteristic is the key factor affecting road radiation transmission process.On the one hand, aerosol scattering characteristic The Planetary albedo of change ball Atmosphere System convertibly, be to affect the break-even important factor of ground vapour system capacity, separately On the one hand, the accurate description of aerosol scattering characteristic, is the key realizing radiation transmission accurate simulation, is that enforcement Atmosphere and Ocean is distant The important physical basis of sense.Muller collision matrix is the important parameter describing aerosol scattering characteristic, not only characterizes scattering energy The spatial distribution characteristic of amount, also establishes turning of incident illumination Stokes vector and different angles scattered light Stokes vector simultaneously Change relation, be one of the core parameter of vector radiative transfer pattern.

Muller collision matrix is simulated by Mie scattering theory for a long time, but owing to actual aerosol is complex-shaped Various, Mie is theoretical the most notable to the simulation error of angle of scattering in rear flank；For solving aerosol particle scattering properties mould Intend, currently also the many aspherical scattering theories of development, such as T matrix method, DDA and FDTD etc., but actual experiment it was found that these The analog result of model there is also a certain degree of uncertainty, simultaneously because the complex refractivity index of Real Atmosphere particulate, The Microphysicals such as scale spectrum, shape of particle and orientation are unknown, cause the practical application of these scattering theories.

For problem above, progressively having developed aerosol Muller collision matrix measurement technology, fundamental measurement principle is to utilize Motor drives optical detector, such as photomultiplier tube (PMT) etc., is scattering on principal plane, with effective scattering region as circle The heart rotates 180 ° or 360 ° and measures scattered light intensity and polarization characteristic thereof in different angle of scatterings, and then inverse Muller scattering square Battle array.At present the technical system of development includes two classes: a class be incident light source and scattered light receiving terminal arrange polaroid and 1/4 or The elements such as 1/2 wave plate, by the machinery rotation of these optical components, change the polarization state of light, and then by different Mullers Matrix element is modulated and is measured on scattered light intensity signal, and under this mechanism, the Muller collision matrix of an angle of scattering is surveyed Amount relate to optical component repeatedly combined machine and rotates, and the most whole process is the most relatively long, it is impossible to monitor that aerosol dissipates Penetrating the Rapid Variable Design of characteristic, owing to Mechanical course is more, certainty of measurement is relatively low；Another kind of mechanism uses photoelectricity phase Position modulation technique, incident illumination, after the polarizer, uses electro-optic phase manipulator that it is carried out high frequency phase modulation, and difference is solemn Strangle matrix element and modulate on different frequency harmonic signal, scattered light measure end by the optical axis of polaroid and quarter wave plate with The combination of scattering plane included angle realizes the screening of different matrix element, is then realized the unit of Muller matrix by phase lock amplifying technology The measurement of element, this machined part overcomes the mechanical Rotation of optical component, but for realizing Muller collision matrix 16 The measurement of element, needs manually to add partial optical device or remove, and automaticity is not enough, there is also measurement excessive cycle Shortcoming, in this mechanism, measurement apparatus is mainly used in the aerocolloidal observation of experiment sample simultaneously, not yet realizes natural aerosol The measurement of Muller collision matrix.In general, Muller collision matrix measuring instrument is still in the experimental prototype stage, there is automatization's journey Spending deficiency, measure time-consuming long shortcoming, measurement object is mainly for laboratory particle simultaneously, for the aerocolloidal sight of natural atmosphere Survey experimental apparatus is few, it is impossible to meet high accuracy radiation transmission simulation and the demand of climatological research, therefore, if can build and grind Send out natural atmosphere aerosol Muller collision matrix measurement apparatus full automatic, it is achieved the aerosol Muller under the conditions of natural atmosphere dissipates Penetrate matrix quickly, accurately measure, either for atmosphere environment supervision, atmospheric radiative transfer simulation and other field research all There is using value.

Utility model content

The purpose of this utility model is the quick, accurate, certainly of solution natural atmosphere aerosol Muller collision matrix total factor Dynamicization is measured, and provides scattering parameter the most accurately for radiation transmission simulation, provides standard for Atmosphere and Ocean remote sensing, climatological research True infrastest data, thus propose a kind of natural atmosphere aerosol Muller matrix self-operated measuring unit.

For reaching above-mentioned purpose, the technical solution of the utility model is: a kind of natural atmosphere aerosol Muller matrix is automatic Measurement apparatus, it includes the light source cell of incident illumination for producing different polarization state, exports, with light source cell, the light being connected Scattering unit, with the light scattering elements scattered light collection that is connected of output and measuring unit, the gas being connected with light scattering elements input Body pretreatment unit, the data acquisition being all connected with said units and control unit and with data acquisition and control unit phase Data processing unit even.

Described light source cell includes laser instrument and incident light polarization modulating system；Described light scattering elements include seal closure, Rotating servo system, ligh trap and monitor；Described scattered light collection and measuring unit include polarizing demodulating system and photon counting Device；Described data acquisition and control unit include CPLD data acquisition circuit, single chip machine controlling circuit and light polarization modulation and Demodulating system control circuit；Described data processing unit is for carry out subsequent treatment to data.

Described light source cell includes laser instrument, the first polaroid and first and second liquid crystal phase retardation device, and wherein first is inclined Shake sheet optical axis and horizontal plane angle is 0 °, as the polarizer of incident illumination, the optical axis of the first liquid crystal phase retardation device (LCVR1) with Horizontal plane is 45 °, the optical axis of the second liquid crystal phase retardation device (LCVR2) horizontal by 0 °, wherein the first polaroid and first, Two liquid crystal phase retardation devices constitute the Polarization Modulation system of incident illumination, and the laser of laser emitting sequentially passes through the first polarization Sheet, the first liquid crystal phase retardation device and the injection of the second liquid crystal phase retardation device, by the phase place of first and second liquid crystal phase retardation device Delay angle δ₁And δ₂Combination arrange, change incident illumination Stokes vector；It is mutual that light source cell should at least produce four kinds of Stokes vectors Incoherent incident illumination, and the Matrix condition number of four kinds of light Stokes vector compositions is little.Incident laser power can be according to different Measure the scattered light intensity at angle of scattering dynamically to adjust.

Described scattered light collection and measuring unit include third and fourth liquid crystal phase retardation device, the second polaroid and photon Enumerator forms, and wherein the three, the 4th liquid crystal phase retardation devices and the second polaroid constitute scattered light signal demodulating system, its In the 3rd liquid crystal phase retardation device (LCVR3) optical axis horizontal by 0 ° of angle, the optical axis of the 4th liquid crystal phase retardation device (LCVR4) Horizontal by 45° angle, the optical axis of the second polaroid is horizontal by 0 ° of angle；In the 3rd liquid crystal phase retardation device LCVR3 front end Add a collimation osculum or diaphragm, for limiting the reception solid angle of scattered light collection and measuring unit and suppressing veiling glare Interference to the process of measurement.Wherein scattered light passes sequentially through diaphragm, LCVR3, LCVR4 and polaroid (or analyzer) and enters photon Enumerator measures；By Polarization Modulation system, Q, U and the V component of scattered light Stokes vector are modulated on I component, so Afterwards by arranging the phase-delay quantity of LCVR3 and LCVR4, I component is carried out four measurements in a closed series, construct system of linear equations, real Now scattered light Stokes vector is solved.Scattered light passes sequentially through LCVR3, LCVR4 and analyzer enters photon counter, logical Cross combination and control the phase-delay quantity realization of third and fourth liquid crystal phase retardation device measurement to scattered light Stokes vector, be limited The reception solid angle of scattered light measuring unit processed also suppresses the veiling glare interference to the process of measurement, adds a collimation in front end little Mouth or diaphragm.

Airflow stability is monitored by described monitor, and scattering light measurement signal is done normalized, this supervision Device is positioned between angle of scattering 30 °～40 °, and its front end is placed with collimation osculum or diaphragm, and seal closure mainly realizes experiment and measures Region and extraneous isolation, prevent the interference of external stray light and air, and the internal coating black coating of seal closure suppresses scattered light Reflection.

Described gas pretreatment unit includes nozzle, receiving pipeline, air flow meter and air pump, and wherein the diameter of nozzle is less than connecing Receive pipe diameter, while there being a distance between nozzle and receiving pipeline, but can not be too big, gas sampling uses port of export air pump to take out The mode of gas is carried out, to prevent particulate from polluting other region outside scattering region.

Described acquisition and control system includes CPLD data acquisition circuit, single chip machine controlling circuit and light polarization modulation And the part such as demodulating system control circuit, mainly realizing light source power regulation, the retardation of liquid crystal phase retardation device adjusts, rotates The control of servosystem, light scattering data collection and with the functions such as the communication of host computer.

Described data processing unit mainly realizes the process of the communication with slave computer and measurement data, for computer software, Wherein data process content includes the storage of measurement data, the different inverse of angle of scattering Muller matrix, the normalized of matrix.

Basic functional principle the most of the present utility model is at different angle of scatterings, produces four groups of Stokes vectors the most not phase The incident illumination closed, and accurately measure four groups of scattered light Stokes vectors of correspondence, and then realize Muller matrix at different angle of scattering Inverse.

Compared with prior art, the natural atmosphere of the measurement in a closed series mode that postpones based on leggy that this utility model is proposed Aerosol Muller collision matrix self-operated measuring unit, has an advantage of the following aspects:

(1) automatic observation of Muller collision matrix is achieved, except rotary servo external demand is adjusted by motor Outward, remaining is measured parts and all realizes electricity tune, and measuring speed is obviously improved that (phase place of liquid crystal phase modulator adjusts the time and is only 2ms～5ms)；

(2) optical component all solidifies, and measurement process is not related to being increased or decreased of components and parts；

(3) use photon counting to measure technology and incident laser power dynamic development adjustment, both can realize faint scattered light Measurement, the most expansible scattered light intensity measurement dynamic range, be applicable to the measurement of nature aerosol Muller collision matrix.

Accompanying drawing explanation

Fig. 1 is theory diagram of the present utility model.

Fig. 2 is structured flowchart of the present utility model.

Fig. 3 is the structured flowchart of light source cell in this utility model.

Fig. 4 is scattered light collection and the structured flowchart of measuring unit in this utility model.

Fig. 5 is the light channel structure figure of monitor in this utility model.

Fig. 6 is the structure chart of gas pretreatment unit in this utility model.

Fig. 7 is data acquisition and the execution flow chart of control unit in this utility model.

Detailed description of the invention

Embodiment: as shown in figs. 1-7, this utility model provides a kind of nature postponing measurement in a closed series mode based on leggy The specific embodiment of atmospheric aerosol Muller matrix self-operated measuring unit, it includes the incident illumination for producing different polarization state Light source cell, export with light source cell be connected light scattering elements, with the light scattering elements scattered light collection that is connected of output and Measuring unit, the gas pretreatment unit, the data acquisition being all connected with said units and the control that are connected with light scattering elements input Unit processed and the data processing unit being connected with control unit with data acquisition.Below in conjunction with the accompanying drawings to of the present utility model Detailed description of the invention describes in detail.

Light source cell major function is to produce the incident illumination of different polarization state, needs at least to produce in this experimental provision The incident illumination that four groups of Stokes vectors are orthogonal, as shown in Figure 3, this unit is by laser instrument, the first polarization for its basic structure Sheet and first and second liquid crystal phase retardation device (LCVR1 and LCVR2) are constituted, and wherein the first polaroid optical axis presss from both sides with reference level surface Angle is 0 °, and as the polarizer of incident illumination, the optical axis of LCVR1 and LCVR2 and horizontal plane angle are respectively 45 ° and 0 °, Qi Zhong One polaroid (or polarizer), first and second liquid crystal phase retardation device LCVR1 and LCVR2 constitute the Polarization Modulation system of incident illumination System, by the phase-delay quantity δ of first and second liquid crystal phase retardation device₁And δ₂Combination arrange (δ₁It it is the Phase delay of LCVR1 Amount, δ₂It is the phase-delay quantity of LCVR2), the control of incident illumination Stokes vector can be realized.Based on Stokes vector calculus rule And the Muller matrix calculation function of each device, after incident laser sequentially passes through polaroid (polarizer), LCVR1 and LCVR2, outgoing The Stokes vector S of laser_LCVR2It is represented by:

S_LCVR2=M_LCVR2·M_LCVR1·M_P·S_unpolarized (1)

Wherein M_P,M_LCVR1,M_LCVR2It is respectively the first polaroid and LCVR1, the Muller matrix S of LCVR2_unpolarized=(I₀, 0,0,0) it is the Stokes vector of non-polarized Raman laser of laser original transmitted, I₀For incident intensity.By each matrix concrete form Substitute into formula (1) successively, therefore, from the Stokes vector S of LCVR2 shoot laser_LCVR2Can be further represented as:

$S_{LCVR2}=\left(\begin{array}{cccc}1& 0& 0& 0\\ 0& 1& 0& 0\\ 0& 0& {\mathrm{cos\δ}}_2& {\mathrm{sin\δ}}_2\\ 0& 0& -{\mathrm{sin\δ}}_2& {\mathrm{cos\δ}}_2\end{array}\right)\left(\begin{array}{cccc}1& 0& 0& 0\\ 0& {\mathrm{cos\δ}}_1& 0& -{\mathrm{sin\δ}}_1\\ 0& 0& 1& 0\\ 0& {\mathrm{sin\δ}}_1& 0& {\mathrm{cos\δ}}_1\end{array}\right)\left(\begin{array}{cccc}1/2& 1/2& 0& 0\\ 1/2& 1/2& 0& 0\\ 0& 0& 0& 0\\ 0& 0& 0& 0\end{array}\right)S_{unpolarized}---\left(2\right)$

Arrangement above formula can get

$S_{LCVR2}=\frac{I_0}{2}\left(\begin{array}{c}1\\ {\mathrm{cos\δ}}_1\\ {\mathrm{sin\δ}}_1{\mathrm{sin\δ}}_2\\ {\mathrm{sin\δ}}_1{\mathrm{cos\δ}}_2\end{array}\right)---\left(3\right)$

From above formula, arranged by the combination of phase-delay quantity δ 1, δ 2, different Stokes vector incident illumination can be realized Produce, the requirement of this experimental provision can be met.The combination of one group of δ 1 and δ 2 is given, it is ensured that produce 4 kinds of Stokes herein The incoherent incident illumination of vector, design parameter arranges as shown in table 1, the combination of the δ 1 and δ 2 of this table reflection incident illumination unit and phase Answer the relation of Output of laser Stokes vector.

Table 1

In addition, for realizing the measurement of Larger Dynamic scattered light, have employed the dynamic Adjusted Option of laser power.Work as measurement During forward scattering light, owing to scattered energy is relatively strong, for preventing the saturated phenomenon of photon counter, laser instrument can be controlled by incidence Luminous power is suitably turned down；For the side rear orientation light that energy is more weak, the most suitably increase incident optical power to improve scattering energy Value.

Scattered light collection and measuring unit mainly realize scattered light Stokes vector measurement.Its basic thought is by polarization The Q of scattered light Stokes vector, U and V component are modulated on I component by modulating system, are then surveyed by the repeatedly combination of I component Amount, constructs system of linear equations, it is achieved component each to scattered light Stokes vector solves.As shown in Figure 4, this unit is by Three, four liquid crystal phase retardation devices (LCVR3 and LCVR4), the second polaroid (or analyzer) and photon counter composition, the 3rd, Four liquid crystal phase retardation devices and the second polaroid constitute scattered light signal demodulating system, wherein the optical axis of LCVR3 and LCVR4 with The angle of reference level surface is respectively 0 ° and 45 °, and corresponding phase-delay quantity δ 3 and δ 4, the second polariser is horizontal by 0 ° of angle (inspection polarization function), photon counter is for realizing the measurement to faint scattered light.For limiting the reception of scattered light measuring unit Angle also suppresses the interference of veiling glare, adds a collimation osculum or diaphragm in front end, it is ensured that higher angular resolution.

At an angle of scattering, the measuring principle of scattered light Stokes vector is as follows simultaneously:

After scattered light sequentially passes through LCVR3, LCVR4 and the second polaroid, arrival photon counter, equally, based on Stokes vector calculus rule and the Muller matrix of each device, arrive the scattered light Stokes vector S of photon counter_measurement Available formula (4) represents, wherein M_P1, M_LCVR4, M_LCVR3It is respectively the second polaroid (or analyzer), the Muller of LCVR3 and LCVR4 Matrix, S_sc=(I, Q, U, V) is the Stokes vector of scattered light.The concrete form of each matrix is substituted into the available formula of formula (4) (5), further abbreviation can get formula (6).

S_measurement=M_P1·M_LCVR4·M_LCVR3·S_sc (4)

$S_{measurement}=\left(\begin{array}{cccc}\frac{1}{2}& \frac{1}{2}& 0& 0\\ \frac{1}{2}& \frac{1}{2}& 0& 0\\ 0& 0& 0& 0\\ 0& 0& 0& 0\end{array}\right)\left(\begin{array}{cccc}1& 0& 0& 0\\ 0& {\mathrm{cos\δ}}_4& 0& -{\mathrm{sin\δ}}_4\\ 0& 0& 1& 0\\ 0& {\mathrm{sin\δ}}_4& 0& {\mathrm{cos\δ}}_4\end{array}\right)\left(\begin{array}{cccc}1& 0& 0& 0\\ 0& 1& 0& 0\\ 0& 0& {\mathrm{cos\δ}}_3& {\mathrm{sin\δ}}_3\\ 0& 0& -{\mathrm{sin\δ}}_3& {\mathrm{cos\δ}}_3\end{array}\right)\left(\begin{array}{c}I\\ Q\\ U\\ V\end{array}\right)---\left(5\right)$

$S_{measurement}=\frac{1}{2}\left(\begin{array}{c}I+{\mathrm{cos\δ}}_4\·Q+{\mathrm{sin\δ}}_3{\mathrm{sin\δ}}_4\·U-{\mathrm{cos\δ}}_3{\mathrm{sin\δ}}_4\·V\\ I+{\mathrm{cos\δ}}_4\·Q+{\mathrm{sin\δ}}_3{\mathrm{sin\δ}}_4\·U-{\mathrm{cos\δ}}_3{\mathrm{sin\δ}}_4\·V\\ 0\\ 0\end{array}\right)---\left(6\right)$

Knowable to above formula, light intensity I that photon counter measurement obtains_m(I_mRepresent the scattered light measured by photon counter Stokes vector S_measurementFirst element, m subscript represents the meaning of measurement, i.e. measure initial) can be written as

$\begin{array}{c}{I}_m=\frac{1}{2}\left(\begin{array}{cccc}1,& {\mathrm{cos\δ}}_4,& {\mathrm{sin\δ}}_3{\mathrm{sin\δ}}_4,& -{\mathrm{cos\δ}}_3{\mathrm{sin\δ}}_4\end{array}\right)\left(\begin{array}{c}I\\ Q\\ U\\ V\end{array}\right)\\ =x^T\·S_{sc}\end{array}---\left(7\right)$

Vector in formula(T representing matrix transposition).Formula (8) is given One can by arranging phase-delay quantity δ₃And δ₄And change the linear equation of coefficient, therefore can be by δ₃And δ₄Combination sets Putting (totally four groups), structure system of linear equations just can realize S_scSolving of four components, concrete grammar is as follows: arrange four groups different δ₃And δ₄Combination, determine one group vectorIt is allowed to orthogonal, from formula (8), for In i-th vectorThe number of times (i=1,2,3,4) of measurement [i represent], all has following formula to set up:

$I_m^i=x_i^T\·S_{sc}---\left(8\right)$

More than simultaneous four linear equation, can form one matrix equation of matrix

I_measurement=X S_sc (9)

WhereinFor measuring vector,It is referred to as measurement coefficient matrix, Therefore from simple matrix knowledge

S_sc=X^-1·I_measurement (10)

From formula (11), by the phase-delay quantity δ of four LCVR3 and LCVR4₃And δ₄Combination control, just can realize To scattered light Stokes vector S_scMeasurement, it will be appreciated, however, that owing to herein being related to matrix inversion operation, therefore matrix X Conditional number is little.Provide one group of δ herein₃And δ₄Combination, as shown in table 2, scattered light collection and measuring unit phase delay device A kind of combined value and corresponding x^TVector.

Table 2

Light scattering elements includes monitor, rotating servo system, ligh trap and seal closure.Monitor is for the master of scattered light intensity The supervision of airflow stability to be used for and the normalized of scattering light measurement signal, this monitor is positioned over 30 ° of positions of angle of scattering Putting place, similar with measuring unit with scattered light collection, same collimation osculum or diaphragm are placed in front end, as shown in Figure 5.Light Trap is used for absorbing direct transmission light, to prevent it from reflecting to form interference.Rotating servo system is a high-precision rotation platform, The anglec of rotation is controlled by motor, and its function is to drive scattered light collection and measuring unit centered by effective scattering object Rotate and arrive the measurement angle of scattering specified.Seal closure mainly realizes testing measured zone and extraneous isolation, prevents extraneous empty The entrance of gas and the interference of external stray light, scribble blacking to suppress the reflection of scattered light inside seal closure.

Gas pretreatment unit includes that receiving pipeline that nozzle and nozzle be oppositely arranged, air-flow to receiving pipeline are carried out The air flow meter measured and the air pump being connected with receiving pipeline, as shown in Figure 6, a diameter of 2mm of nozzle, receiving pipeline bore At 2cm, nozzle end is 1cm with the axial distance of receiving pipeline.This unit uses the mode that the air pump of the port of export is bled, so It is advantageous in that and can produce secondary pressure between nozzle and receiving pipeline, prevent sampling air flow to non-scatter regional diffusion, pollute work Make region.Receiving pipeline internal diameter is much larger than air intake diameter, and after its reason is that airflow through nozzle, can dash forward in the cross section of sampling air flow So increasing, the cross section increasing receiving terminal is conducive to receiving sampling air flow completely, prevents from being blown into non-scatter district containing aerocolloidal air-flow Territory.

The embodiment of whole measurement process as shown in Figure 7, is embodied as operating procedure as follows:

(1) experimental provision initializes.Pre-to laser instrument, photon counter, monitor and Polarization Modulation and demodulating unit etc. Heat, preheating time about 30min；Carry out the startup test of rotating servo system, determine its working properly after, and drive light scattering Measuring unit measures angle of scattering position to minimum.

(2) servo Spin Control.Controlling motor and drive scattered light collection and measuring unit high-precision rotary, arrival refers to Stop after determining scatteringangleθ.

(3) the incident light polarization modulating system of light source cell is controlled, by LCVR1 and LCVR2 phase-delay quantity δ₁And δ₂'s Combination, produces the incident illumination of a certain special polarization state (choosing the one to table 1), if its Stokes vector。

(4) the polarization demodulating system of scattered light collection and measuring unit is controlled, it is achieved specify scattered light at angle of scattering The measurement of Stokes vector, measured value is designated as.It should be noted that every time polarization demodulating system state changes and starts to measure Time, needing to stop about 100ms, its reason is that photon counter measurement process needs certain time of integration.

(5) at same scatteringangleθ, control incident light polarization modulating system, sequentially generate other three kinds of differences in table 1 The incident illumination of Stokes vector, then under the conditions of every kind of incident illumination, performs step (4) successively.It is hereby achieved that four groups different The Stokes vector of incident illumination (is designated as) and the Stokes vector of corresponding scattered light, it is designated asMeanwhile record the measured value of monitor.Repeat this process 50 times, obtain 50 groups of differences Measurement data, be averaged as final measurement result.Then corresponding measurement data is sent to host computer, the number of transmission According to including: measured angle of scattering, the Stokes vector of incident illumination, monitor light intensity average measurement value I_scan, scattered light Stokes vector.

(6) step of (2) to (5) is repeated, under the conditions of same incident illumination, it is achieved at each angle of scattering, four groups dissipate Penetrate the measurement of light Stokes vector, and data are stored, then pass through serial ports (such as RS232) or netting twine communication (such as TCP/ IP) transfer data to host computer, carry out next step data process.

During it should be noted that a perfect measurement, step (2) to (6) needs to carry out twice, is once at purity nitrogen Carrying out under the conditions of gas, obtain scattering background value, another time is to carry out under the conditions of the air containing aerosol is passed through, and two groups of data are subtracted each other Obtain aerocolloidal scattering light distribution characteristic.

(7) on host computer, the data recorded are stored according to rule with text formatting or binary file form, Owing to the Stokes vector of scattered light is to be obtained incident illumination Stokes vector linear transformation by Muller collision matrix M (θ), because of This incident illumination Stokes vector S_incThere is relationship below in matrix and scattered light Stokes vector matrix:

S_sc=M (θ) S_inc (10)

Therefore by matrix operations, can be easy to solve and obtain Muller collision matrixFor ensureing inverse square Battle array operation, it is necessary to assure the Stokes vector of four groups of incident illuminations is orthogonal, and matrix S_incConditional number can not be too big, prevent The morbid state of solution procedure.

Next matrix is normalized, wherein matrix element M₁₁(θ) (the unit of Muller matrix M (θ) the first row first row Element) use monitor meansigma methods I_scanBeing normalized, other matrix element uses M₁₁(θ) it is normalized.

This utility model cannot be only used for the measurement of nature aerosol Muller matrix, it may also be used for the survey of sample aerosol Amount.

Certainly above-described embodiment is only for illustrating technology of the present utility model design and feature, its object is to allow and is familiar with this The people of technology will appreciate that content of the present utility model and implements according to this, can not limit protection model of the present utility model with this Enclose.All equivalent transformations done according to the spirit of this utility model main technical schemes or modification, all should contain in this reality Within novel protection domain.

Claims (6)

1. a natural atmosphere aerosol Muller matrix self-operated measuring unit, it is characterised in that it includes for producing different polarization The light source cell of state incident illumination, export the light scattering elements, scattered with what light scattering elements output was connected being connected with light source cell Penetrate the gas pretreatment unit that light collection with measuring unit, is connected, the number being all connected with said units with light scattering elements input According to gathering and control unit and the data processing unit that is connected with control unit with data acquisition.

A kind of natural atmosphere aerosol Muller matrix self-operated measuring unit the most according to claim 1, it is characterised in that: institute State light source cell and include laser instrument and incident light polarization modulating system；Described light scattering elements includes seal closure, rotating servo system System, ligh trap and monitor；Described scattered light collection and measuring unit include polarizing demodulating system and photon counter；Described data Gather and include CPLD data acquisition circuit, single chip machine controlling circuit and light polarization modulation and demodulating system control with control unit Circuit processed.

A kind of natural atmosphere aerosol Muller matrix self-operated measuring unit the most according to claim 2, it is characterised in that: institute State light source cell and include laser instrument, the first polaroid and first and second liquid crystal phase retardation device, wherein the first polaroid optical axis Being 0 ° with horizontal plane angle, as the polarizer of incident illumination, the optical axis of the first liquid crystal phase retardation device is horizontal by 45 ° of folders Angle, the optical axis of the second liquid crystal phase retardation device horizontal by 0 °, wherein the first polaroid and first and second liquid crystal phase retardation device Constituting the Polarization Modulation system of incident illumination, the laser of laser emitting sequentially passes through the first polaroid, the first liquid crystal phase place is prolonged Device and the injection of the second liquid crystal phase retardation device late.

A kind of natural atmosphere aerosol Muller matrix self-operated measuring unit the most according to claim 3, it is characterised in that: institute State scattered light collection and include third and fourth liquid crystal phase retardation device, the second polaroid and photon counter, wherein with measuring unit Third and fourth liquid crystal phase retardation device and the second polaroid constitute scattered light signal demodulating system, and wherein the 3rd liquid crystal phase place is prolonged Device optical axis is horizontal by 0 ° of angle late, and the optical axis of the 4th liquid crystal phase retardation device is horizontal by 45 ° of angles, the second polaroid Optical axis horizontal by 0 ° of angle；Collimation osculum or diaphragm it is provided with in the 3rd liquid crystal phase retardation device front end；Scattered light is successively Through collimation osculum, third and fourth liquid crystal phase retardation device, the second polaroid enter photon counter and measure.

A kind of natural atmosphere aerosol Muller matrix self-operated measuring unit the most according to claim 2, it is characterised in that: Airflow stability is monitored by described monitor, and scattering light measurement signal is done normalized, and this monitor is positioned over Between angle of scattering 30 °～40 °, its front end is placed with collimation osculum or diaphragm, scribbles blacking inside seal closure.

A kind of natural atmosphere aerosol Muller matrix self-operated measuring unit the most according to claim 1, it is characterised in that: institute Stating gas pretreatment unit and include nozzle, receiving pipeline, air flow meter and air pump, wherein the diameter of nozzle is less than receiving pipeline mouth Having a distance between footpath, and nozzle and receiving pipeline, the mode that gas sampling uses port of export air pump to bleed is carried out.