CN106289542A - A kind of radiation correction method of preposition polaroid type infrared polarization imaging system - Google Patents

Abstract

The radiation correction method of a kind of preposition polaroid type infrared polarization imaging system disclosed by the invention, relates to the radiation correction method of infrared polarization imaging system, belongs to image procossing and test and measuring technical field.The present invention carries out gradation of image irradiance mapping relations and demarcates the infrared imaging system removing analyzing mechanism；Then, use infrared polarization imaging system to obtain Same Scene analyzing passage and the gray level image of intensity channel, according to the demarcation relation that matching obtains, the gray level image gathered is carried out the conversion from gray scale to irradiance；Finally, solve stokes parameter and polaroid reflected radiation and self radiation according to the Muller matrix of preposition polaroid type infrared polarization imaging system analyzing link, complete the correction to stokes parameter.The present invention can eliminate preposition polaroid reflected radiation and self radiates the adverse effect causing polarization imaging measurement, reduces the measurement of scene radiation polarisation parameter and calculates error, improving the accuracy of system polarization information.

Description

A kind of radiation correction method of preposition polaroid type infrared polarization imaging system

Technical field

The present invention relates to the radiation correction method of a kind of infrared polarization imaging system, particularly relate to a kind of for preposition polarization The radiation correction method of chip infrared polarization imaging system, belongs to image procossing and test and measuring technical field.

Background technology

Polarization is one of key property of electromagnetic radiation, owing to object reflection and self radiation are often with object self Polarization characteristic, these differences of target scene can be that target acquisition provides new information.Along with infrared focal plane detector skill The development of art, detector sensitivity is significantly improved so that Infrared Polarization Imaging Technology moves towards rapidly practical, and substantially carries Rise the effectiveness of target acquisition under complex background or intense radiation jamming pattern.

Polarized imaging system obtains mode according to polarization image can be divided into timesharing and both of which simultaneously.Timesharing polarizes As instrument is at the image obtaining same scenery different polarization states the most in the same time, it is adaptable to static target, it is achieved mode mainly includes partially The sheet that shakes is polarized formula and polarizing prism beam splitting type；Polarization imager can obtain 4 width different polarization of target by single exposure simultaneously Image, the most applicable for static target and moving target, it is achieved mode is broadly divided into point amplitude polarization imaging, point aperture simultaneously Polarization imaging and point focal plane polarization imaging simultaneously simultaneously.By installing polaroid before optical system or imaging focal plane with reality The polarization imaging structure of existing analyzing is owing to having simple in construction, with low cost, the most conventional in polarization imaging is measured.

For preposition polaroid visible ray polarized imaging system, polaroid is non-substantially without introducing in the range of imaging band The extraneous emission of scene；But for applying the infrared polarization imaging system of preposition polarizer constructions, red except from scene External radiation, the spontaneous radiation of polaroid and reflected radiation all will be imaged region and receive, thus cause the distortion of incident radiation, And then affect the follow-up resolving of scene polarization information.Especially for non-refrigeration type LONG WAVE INFRARED polarized imaging system, preposition partially The harmful effect that the sheet that shakes introduces will be the most notable.

The polarization imaging model that conventional polarization information method for solving uses mostly does not accounts for the attached of preposition polaroid introducing Adding radiation, as a example by Single-channel Rolling polaroid type infrared polarization imaging system, its imaging model is as shown in Figure 2.It practice, examine The spontaneous radiation of worry polaroid and imaging system self heat radiation are reflected back the spurious radiation of optical system through polaroid, and count And polaroid principal direction and the transmitance of orthogonal direction thereof, the correction of Single-channel Rolling polaroid type infrared polarization imaging system is former Reason figure otherwise should certainly will cause calculating error as it is shown on figure 3, the method for solving of polarization parameter also should make corresponding amendment.

In sum, for preposition polaroid type infrared polarization imaging system, radiant correction link is essential.How to have Completing preposition polaroid radiant correction to effect, that reduces polarization information solves error, is a key issue being worth solving.

Summary of the invention

The radiation correction method of a kind of preposition polaroid type infrared polarization imaging system disclosed by the invention, skill to be solved Art problem is to eliminate preposition polaroid reflected radiation and self radiate the adverse effect causing polarization imaging measurement, reduction scene The measurement of radiation polarisation parameter and calculating error, improve the accuracy of system polarization information.

The radiation correction method of a kind of preposition polaroid type infrared polarization imaging system disclosed by the invention, first, to shifting Demarcate except the infrared imaging system of analyzing mechanism carries out gradation of image irradiance mapping relations；Then, infrared polarization is used to become As system obtains Same Scene analyzing passage and the gray level image of intensity channel, the demarcation relation that obtains according to matching is to gathering Gray level image carries out the conversion from gray scale to irradiance；Finally, according to preposition polaroid type infrared polarization imaging system analyzing ring The Muller matrix (Mueller Matrix) of joint solves stokes parameter (Stokes parameters) and polaroid reflection spoke Penetrate and self radiation, complete the correction to stokes parameter.

Compare the situation not considering that preposition polaroid affects, use the stokes parameter that the inventive method calculates with inclined Degree of shaking is the most accurate, thus is more beneficial for the polarization characteristic of reduction observation scene.

The radiation correction method of a kind of preposition polaroid type infrared polarization imaging system disclosed by the invention, specifically include with Lower step:

Step 1, carries out gradation of image irradiance mapping relations and demarcates the infrared imaging system removing analyzing mechanism.

Step 1.1, first, uses infrared imaging system to be calibrated to obtain face type blackbody radiation source at different temperatures red Outer gray level image.

Method particularly includes: under room temperature environment, placed side type beyond 10 times of focal lengths of infrared imaging system dead ahead to be calibrated Blackbody radiation source, is set to comprise the Regular temperature ranges of thermal imaging system photographed scene by blackbody temperature excursion, and temperature range is excellent Select 298.15K～393.15K, interval sampling temperature value, and use infrared imaging system to be calibrated to shoot one group of black matrix clearly Radiation source image.Described interval sampling is preferably every 5K one temperature value of sampling.

Step 1.2, matching gradation of image irradiance mapping curve, i.e. complete the gradation of image of infra-red thermal imaging system Irradiance mapping relations are demarcated.

Calculation procedure 1.1 is often organized image blackbody radiation source and occupies the average gray of part, and according to blackbody radiation emission Rate and Planck (Plank) formula calculate the blackbody radiation source radiant exitance in imaging system response wave band.Afterwards according to meter Count according to matching gradation of image black body radiation emittance mapping relations curve, i.e. complete the image ash of infra-red thermal imaging system Degree irradiance mapping relations are demarcated.

It is directly proportional owing to radiant exitance receives illumination to detector, replaces irradiance by radiant exitance below.

Method particularly includes:

Occupy according to black matrix heat picture average gray computing formula (1) calculation procedure 1.1 often organizes image blackbody radiation source The average gray of part,

$\stackrel{\‾}{G}=\frac{\underset{A}{\Σ}G}{\underset{A}{\Σ}1}---\left(1\right)$

In formula,For boldface average gray, G is gradation of image, and A is the pixel region that in image, black matrix occupies.

Blackbody radiation source giving off in imaging system response wave band is calculated according to black body radiation emittance computing formula (2) Degree of penetrating,

$M={\mathrm{\ϵ}}_{BB}\underset{{\mathrm{\λ}}_1}{\overset{{\mathrm{\λ}}_2}{\∫}}\[\frac{c_1}{{\mathrm{\λ}}^5}\frac{1}{\exp (c_2/\mathrm{\λ}T)}-1\]d\mathrm{\λ}---\left(2\right)$

In formula, M is the face type blackbody radiation source radiant exitance in imaging system response wave band；ε_BBFor blackbody radiation source Radiant emissivity, λ₁、λ₂It is respectively lower limit wavelength and the upper limit, the c of imaging system response wave band₁、c₂It is respectively first, second spoke Penetrate constant.

The black matrix heat picture average gray calculated according to formula (1) is being become with the black matrix calculated according to formula (2) As the radiant exitance of system response wave band is fitted, matched curve form is formula (3),

$\stackrel{\‾}{G}=a\×M^{\mathrm{\γ}}+b---\left(3\right)$

In formula, a, b are respectively gain and biasing coefficient, and γ is non-linear for characterize between output signal and input radiation amount Effect.

Approximating method described in step 1.2 can be nonlinear least square method or trust region method etc..

Step 2, uses infrared polarization imaging system to obtain Same Scene analyzing passage and the gray level image of intensity channel, institute The intensity channel stated refers to not install analyzing mechanism thus directly obtains the imaging band of scene radiation.Intend according in step 1.2 Close the demarcation relation obtained and the gray level image gathered is carried out the conversion from gray scale to irradiance.And it is red according to preposition polaroid type The Muller matrix of outer polarized imaging system analyzing mechanism solves stokes parameter and polaroid reflected radiation and self radiation, complete The correction of stokes parameter in pairs.

Beneficial effect:

1, the radiation correction method of a kind of preposition polaroid type infrared polarization imaging system disclosed by the invention, it is considered to infrared The impact that during polarization imaging, preposition polaroid reflected radiation and self radiation introduce, receives in radiation detector and carrys out self-fields Scape and the two parts from polaroid make a distinction, and accurately reflect the imaging of preposition polaroid type infrared polarization imaging system Journey.

2, the radiation correction method of a kind of preposition polaroid type infrared polarization imaging system disclosed by the invention, solves and obtains Incident radiation stokes parameter and degree of polarization accuracy higher, i.e. correction after stokes parameter accuracy higher, Eliminate preposition polaroid reflected radiation and self radiates the adverse effect causing polarization imaging measurement, reduce scene radiation polarisation The measurement of parameter and calculating error, improve the accuracy of system polarization information, is more beneficial for the polarization characteristic of reduction observation scene.

Accompanying drawing explanation

Fig. 1 is the radiation correction method flow chart for preposition polaroid type infrared polarization imaging system.

Fig. 2 is not consider the Single-channel Rolling polaroid type infrared polarization imaging system images schematic diagram that polaroid affects.

Fig. 3 is the Single-channel Rolling polaroid type infrared polarization imaging system images schematic diagram considering polaroid impact.

Fig. 4 is that polaroid type infrared polarization imaging system images schematic diagram fixed by Single-channel Rolling wave plate.

Fig. 5 is real-time four-way infrared polarization imaging system images schematic diagram.

Detailed description of the invention

For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to attached Figure, the present invention is described in more detail.It is to be noted that described example is the understanding for the ease of the present invention, and right It does not play any restriction effect.The method that the present invention provides both can be at the single channel timesharing infrared polarization with preposition polaroid Imaging system uses, it is also possible to use in the polarized imaging system simultaneously of the multichannel with preposition polaroid.

The radiation correction method for preposition polaroid type infrared polarization imaging system that the present invention provides, including to removing The infrared imaging system of analyzing mechanism carries out gradation of image irradiance mapping relations and demarcates；And to infrared polarization imaging system The gray scale that analyzing channel image and intensity channel image are carried out is to the conversion of amount of radiation with to stokes parameter and polaroid Reflected radiation solves with self radiation.Compare the situation not considering that preposition polaroid affects, use the inventive method to calculate Stokes parameter and degree of polarization the most accurate, thus be more beneficial for reduction observation scene polarization characteristic.

Embodiment 1:

The Single-channel Rolling polaroid type infrared polarization imaging system structure that the embodiment of the present invention 1 uses mainly includes revolving Rotatable preposition polaroid and thermal infrared imager.This system imaging schematic diagram is as it is shown on figure 3, S_inRepresent the linear stoke of incident radiation This vector, I represents the radiation value that image planes receive, and R represents the radiation value from preposition polaroid, τ₁、τ₂Represent preposition polarization respectively Sheet principal direction and the energetic transmittance of orthogonal direction thereof, ρ represents the energetic transmittance of polaroid back-end optical system.

For the radiation correction method of Single-channel Rolling polaroid type infrared polarization imaging system in the present embodiment 1, specifically Implement step to include:

Step 1, carries out image to the Single-channel Rolling polaroid type infrared polarization imaging system after removing preposition polaroid Gray scale irradiance mapping relations are demarcated.

Step 1.1, first, uses the Single-channel Rolling polaroid type infrared polarization imaging system after removing preposition polaroid Acquisition face type blackbody radiation source infrared hybrid optical system at different temperatures.

Method particularly includes: the Single-channel Rolling polaroid type infrared polarization under room temperature environment, after removing preposition polaroid Placed side type blackbody radiation source beyond 10 times of focal lengths of imaging system dead ahead, is set to comprise thermal imaging system by blackbody temperature excursion The Regular temperature ranges of photographed scene, preferred 298.15K～393.15K of temperature range, interval sampling temperature value, and use and wait to mark Determine infrared imaging system and shoot one group of black body radiation source images clearly.Described interval sampling is preferably every 5K one temperature of sampling Angle value.

Step 1.2, matching gradation of image irradiance mapping curve, i.e. complete the gradation of image of infra-red thermal imaging system Irradiance mapping relations are demarcated.

Calculation procedure 1.1 is often organized image blackbody radiation source and occupies the average gray of part, and according to blackbody radiation emission Rate and planck formula calculate the blackbody radiation source radiant exitance in imaging system response wave band.Afterwards according to calculating data plan Close gradation of image black body radiation emittance mapping relations curve, i.e. complete the gradation of image irradiance of infra-red thermal imaging system Mapping relations are demarcated.

It is directly proportional owing to radiant exitance receives illumination to detector, replaces irradiance by radiant exitance below.

Method particularly includes:

Occupy according to black matrix heat picture average gray computing formula (4) calculation procedure 1.1 often organizes image blackbody radiation source The average gray of part,

$\stackrel{\‾}{G}=\frac{\underset{A}{\Σ}G}{\underset{A}{\Σ}1}---\left(4\right)$

In formula,For boldface average gray, G is gradation of image, and A is the pixel region that in image, black matrix occupies.

Blackbody radiation source giving off in imaging system response wave band is calculated according to black body radiation emittance computing formula (5) Degree of penetrating,

$M={\mathrm{\ϵ}}_{BB}\underset{{\mathrm{\λ}}_1}{\overset{{\mathrm{\λ}}_2}{\∫}}\[\frac{c_1}{{\mathrm{\λ}}^5}\frac{1}{\exp (c_2/\mathrm{\λ}T)}-1\]d\mathrm{\λ}---\left(5\right)$

In formula, M is the face type blackbody radiation source radiant exitance in imaging system response wave band；ε_BBFor blackbody radiation source Radiant emissivity, λ₁、λ₂It is respectively lower limit wavelength and the upper limit, the c of imaging system response wave band₁、c₂It is respectively first, second spoke Penetrate constant.

The black matrix heat picture average gray calculated according to formula (4) is being become with the black matrix calculated according to formula (5) As the radiant exitance of system response wave band is fitted, matched curve form is formula (6),

$\stackrel{\‾}{G}=a\×M^{\mathrm{\γ}}+b---\left(6\right)$

In formula, a, b are respectively gain and biasing coefficient, and γ is non-linear for characterize between output signal and input radiation amount Effect.

Approximating method described in step 1.2 can be nonlinear least square method, trust region method etc..

Step 2, uses Single-channel Rolling polaroid type infrared polarization imaging system photographed scene, obtains same static scene Intensity channel and the gray level image of analyzing passage.When gathering intensity channel image, polaroid is not installed, directly obtains self-fields The incident radiation of scape；Polaroid is installed when gathering analyzing channel image, and altogether needs to gather three times, before rotating before gathering for three times Put polaroid, make polaroid pass through direction and be followed successively by θ with horizontal direction angle₀、θ₁、θ₂, three angles are different, preferably 45 °, 90 ° and 135 °.According to demarcating mapping relations formula (6), gradation of image is scaled irradiance.Analyzing after conversion is led to All pixels in road image and intensity channel image carry out computing according to formula (7), solve this torr of correct incident radiation Gram this parameter and the reflected radiation of polaroid and self radiation:

$\left[\begin{array}{c}I\\ Q\\ U\\ r\end{array}\right]={\left(\frac{1}{2}\left[\begin{array}{cccc}\mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_0& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_0& 2\\ \mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_1& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_1& 2\\ \mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_2& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_2& 2\\ 2\mathrm{\ρ}& 0& 0& 0\end{array}\right]\right)}^{-1}\left[\begin{array}{c}{I}_0\\ I_1\\ I_2\\ I_{NP}\end{array}\right]---\left(7\right)$

In formula, I₀、I₁、I₂It is respectively θ₀、θ₁、θ₂The irradiance value that analyzing channel image pixel grey scale obtains through conversion, I_NP The irradiance value obtained through conversion for intensity channel image pixel gray level；τ₁、τ₂Represent preposition polaroid principal direction and just respectively Hand over the energetic transmittance in direction；ρ represents the energetic transmittance of polaroid back-end optical system, when being concerned only with stokes parameter Can be taken as during relative size between 0～1 be not 0 arbitrary value；I, Q, U represent the intensity of incident radiation Stokes vector respectively Component, level/vertical curve deviatoric component and+45 °/-45 ° line deviatoric components, r represents reflected radiation and self spoke of preposition polaroid Penetrate.

So far, the correction to stokes parameter is completed.

Embodiment 2:

It is main that polaroid type infrared polarization imaging system structure fixed by the Single-channel Rolling wave plate that the embodiment of the present invention 2 uses Including rotary type quarter wave plate, fixing preposition polaroid and LONG WAVE INFRARED thermal imaging system.This system imaging schematic diagram as shown in Figure 4, S_inRepresenting incident radiation Stokes vector, I represents the radiation value that image planes receive, and R represents the radiation value from preposition polaroid, τ_wpRepresent the energetic transmittance of quarter wave plate, τ₁、τ₂Represent that the energy of preposition polaroid principal direction and orthogonal direction thereof passes through respectively Rate, ρ represents the energetic transmittance of polaroid back-end optical system.

The radiant correction side of polaroid type infrared polarization imaging system is fixed for Single-channel Rolling wave plate in the present embodiment 2 Method, is embodied as step and includes:

Step 1, fixes polaroid type infrared polarization to the Single-channel Rolling wave plate after removing wave plate and preposition polaroid and becomes Demarcate as system carries out gradation of image irradiance mapping relations.

Step 1.1, first, uses the Single-channel Rolling wave plate after removing wave plate and preposition polaroid to fix polaroid type red Outer polarized imaging system obtains face type blackbody radiation source infrared hybrid optical system at different temperatures.

Method particularly includes: under room temperature environment, the Single-channel Rolling wave plate after removing wave plate and preposition polaroid is fixing partially Shake placed side type blackbody radiation source beyond chip 10 times of focal lengths of infrared polarization imaging system dead ahead, by blackbody temperature excursion It is set to comprise the Regular temperature ranges of thermal imaging system photographed scene, preferred 298.15K～393.15K of temperature range, interval sampling temperature Angle value, and use infrared imaging system to be calibrated to shoot one group of black body radiation source images clearly.Described interval sampling is preferred Every 5K one temperature value of sampling.

Step 1.2, matching gradation of image irradiance mapping curve, i.e. complete the gradation of image of infra-red thermal imaging system Irradiance mapping relations are demarcated.

Calculation procedure 1.1 is often organized image blackbody radiation source and occupies the average gray of part, and according to blackbody radiation emission Rate and planck formula calculate the blackbody radiation source radiant exitance in imaging system response wave band.Afterwards according to calculating data plan Close gradation of image black body radiation emittance mapping relations curve, i.e. complete the gradation of image irradiance of infra-red thermal imaging system Mapping relations are demarcated.

It is directly proportional owing to radiant exitance receives illumination to detector, replaces irradiance by radiant exitance below.

Method particularly includes:

Occupy according to black matrix heat picture average gray computing formula (8) calculation procedure 1.1 often organizes image blackbody radiation source The average gray of part,

$\stackrel{\‾}{G}=\frac{\underset{A}{\Σ}G}{\underset{A}{\Σ}1}---\left(8\right)$

In formula,For boldface average gray, G is gradation of image, and A is the pixel region that in image, black matrix occupies.

Blackbody radiation source giving off in imaging system response wave band is calculated according to black body radiation emittance computing formula (9) Degree of penetrating,

$M={\mathrm{\ϵ}}_{BB}\underset{{\mathrm{\λ}}_1}{\overset{{\mathrm{\λ}}_2}{\∫}}\[\frac{c_1}{{\mathrm{\λ}}^5}\frac{1}{\exp (c_2/\mathrm{\λ}T)}-1\]d\mathrm{\λ}---\left(9\right)$

In formula, M is the face type blackbody radiation source radiant exitance in imaging system response wave band；ε_BBFor blackbody radiation source Radiant emissivity, λ₁、λ₂It is respectively lower limit wavelength and the upper limit, the c of imaging system response wave band₁、c₂It is respectively first, second spoke Penetrate constant.

The black matrix heat picture average gray calculated according to formula (8) is being become with the black matrix calculated according to formula (9) As the radiant exitance of system response wave band is fitted, matched curve form is formula (10),

$\stackrel{\‾}{G}=a\×M^{\mathrm{\γ}}+b---\left(10\right)$

In formula, a, b are respectively gain and biasing coefficient, and γ is non-linear for characterize between output signal and input radiation amount Effect.

Approximating method described in step 1.2 can be nonlinear least square method, trust region method etc..

Step 2, uses Single-channel Rolling wave plate to fix polaroid type infrared polarization imaging system photographed scene, obtains same The intensity channel of static scene and the gray level image of analyzing passage.When gathering intensity channel image, wave plate and polaroid are not installed, Directly obtain the incident radiation from scene；Installing wave plate and polaroid when gathering analyzing channel image, wherein, polaroid passes through Direction and horizontal direction parallel, and altogether need to gather four times, rotate quarter wave plates before gathering for four times, make wave plate quick shaft direction with Horizontal direction angle is followed successively by θ₀、θ₁、θ₂、θ₃, four angles are different.According to demarcating mapping relations formula (10) by image ash Degree is scaled irradiance.For the analyzing channel image after conversion and all pixels in intensity channel image according to formula (11) Carry out computing, solve correct incident radiation stokes parameter and the reflected radiation of polaroid and self radiates:

$\left[\begin{array}{c}I\\ Q\\ U\\ V\\ r\end{array}\right]={\left(\frac{1}{2}\left[\begin{array}{ccccc}{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)\mathrm{\ρ}& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2){\mathrm{\ρcos}}^{2}2{\mathrm{\θ}}_0& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_0\cos 2{\mathrm{\θ}}_0& -{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_0& 2\\ {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)\mathrm{\ρ}& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2){\mathrm{\ρcos}}^{2}2{\mathrm{\θ}}_1& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_1\cos 2{\mathrm{\θ}}_1& -{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_1& 2\\ {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)\mathrm{\ρ}& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2){\mathrm{\ρcos}}^{2}2{\mathrm{\θ}}_2& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_2\cos 2{\mathrm{\θ}}_2& -{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_2& 2\\ {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)\mathrm{\ρ}& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2){\mathrm{\ρcos}}^{2}2{\mathrm{\θ}}_3& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_3\cos 2{\mathrm{\θ}}_3& -{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_3& 2\\ 2\mathrm{\ρ}& 0& 0& 0& 0\end{array}\right]\right)}^{-1}\left[\begin{array}{c}{I}_0\\ I_1\\ I_2\\ I_3\\ I_{NP}\end{array}\right]---\left(11\right)$

In formula, I₀、I₁、I₂、I₃It is respectively θ₀、θ₁、θ₂、θ₃The irradiance that analyzing channel image pixel grey scale obtains through conversion Value, I_NPThe irradiance value obtained through conversion for intensity channel image pixel gray level；τ_wpRepresent the energetic transmittance of quarter wave plate, τ₁、 τ₂Represent preposition polaroid principal direction and the energetic transmittance of orthogonal direction thereof respectively；ρ represents polaroid back-end optical system Energetic transmittance, can be taken as when being concerned only with the relative size of stokes parameter between 0～1 be not 0 arbitrary value；I、Q、U、 V represent respectively the strength component of incident radiation Stokes vector, level/vertical curve deviatoric component ,+45 °/-45 ° line deviatoric components with And dextrorotation/left-handed round deviatoric component；R represents the reflected radiation of preposition polaroid and self radiates.

So far, the correction to stokes parameter is completed.

Embodiment 3:

The real-time four-way infrared polarization imaging system that the embodiment of the present invention 3 uses mainly comprises the inclined of three same sizes Shake sheet and the thermal infrared imager of four same sizes, and its imaging schematic diagram is as it is shown in figure 5, S_inRepresent incident radiation this torr linear Gram this vector, θ₀、θ₁、θ₂It is respectively three preposition polaroids of analyzing passage angle through direction with horizontal direction, I₀、I₁、I₂ It is respectively θ₀、θ₁、θ₂The radiation value that analyzing passage image planes receive, I_NPFor intensity channel image planes receive radiation value, r represent from The radiation value of preposition polaroid, τ₁、τ₂Representing preposition polaroid principal direction and the energetic transmittance of orthogonal direction thereof respectively, ρ represents The energetic transmittance of polaroid back-end optical system.

For the radiation correction method of four-way infrared polarization imaging system real-time in the present embodiment 3, it is embodied as step Including:

Step 1, the thermal infrared imager using four imaging bands carries out gradation of image irradiance mapping relations respectively Demarcate.The concrete demarcating steps of the thermal infrared imager of each imaging band is:

Step 1.1, first, uses thermal infrared imager to obtain face type blackbody radiation source infrared gray-scale map at different temperatures Picture.

Method particularly includes: under room temperature environment, beyond 10 times of focal lengths of thermal infrared imager dead ahead to be calibrated, placed side type is black Body radiation source, is set to comprise the Regular temperature ranges of thermal imaging system photographed scene by blackbody temperature excursion, and temperature range is preferred 298.15K～393.15K, interval sampling temperature value, and use infrared imaging system to be calibrated to shoot one group of black matrix spoke clearly Penetrate source images.Described interval sampling is preferably every 5K one temperature value of sampling.

Step 1.2, matching gradation of image irradiance mapping curve, i.e. complete the gradation of image irradiation of thermal infrared imager Degree mapping relations are demarcated.

Calculation procedure 1.1 is often organized image blackbody radiation source and occupies the average gray of part, and according to blackbody radiation emission Rate and planck formula calculate the blackbody radiation source radiant exitance in imaging system response wave band.Afterwards according to calculating data plan Closing gradation of image black body radiation emittance mapping relations curve, the gradation of image irradiance i.e. completing thermal infrared imager maps Relation is demarcated.

It is directly proportional owing to radiant exitance receives illumination to detector, replaces irradiance by radiant exitance below.

Method particularly includes:

Occupy according to black matrix heat picture average gray computing formula (12) calculation procedure 1.1 often organizes image blackbody radiation source The average gray of part,

$\stackrel{\‾}{G}=\frac{\underset{A}{\Σ}G}{\underset{A}{\Σ}1}---\left(12\right)$

In formula,For boldface average gray, G is gradation of image, and A is the pixel region that in image, black matrix occupies.

The blackbody radiation source radiation in imaging system response wave band is calculated according to black body radiation emittance computing formula (13) Emittance,

$M={\mathrm{\ϵ}}_{BB}\underset{{\mathrm{\λ}}_1}{\overset{{\mathrm{\λ}}_2}{\∫}}\[\frac{c_1}{{\mathrm{\λ}}^5}\frac{1}{\exp (c_2/\mathrm{\λ}T)}-1\]d\mathrm{\λ}---\left(13\right)$

In formula, M is the face type blackbody radiation source radiant exitance in imaging system response wave band；ε_BBFor blackbody radiation source Radiant emissivity, λ₁、λ₂It is respectively lower limit wavelength and the upper limit, the c of imaging system response wave band₁、c₂It is respectively first, second spoke Penetrate constant.

The black matrix heat picture average gray calculated according to formula (12) and the black matrix calculated according to formula (13) are existed The radiant exitance of imaging system response wave band is fitted, and matched curve form is formula (14),

$\stackrel{\‾}{G}=a\×M^{\mathrm{\γ}}+b---\left(14\right)$

In formula, a, b are respectively gain and biasing coefficient, and γ is non-linear for characterize between output signal and input radiation amount Effect.

Approximating method described in step 1.2 can be nonlinear least square method, trust region method etc..

Step 2, uses real-time four-way infrared polarization imaging system photographed scene, installs polaroid by front end respectively The intensity imaging passage of three polarization imaging passages and front end no polarization sheet obtains analyzing image and the intensity image of Same Scene. According to demarcation mapping relations formula (14) of the thermal infrared imager of each passage use in step 1, respective channel gradation of image is converted For irradiance.Analyzing channel image after conversion and all pixels in intensity channel image are transported according to formula (15) Calculate, solve correct incident radiation stokes parameter and the reflected radiation of polaroid and self radiates:

$\left[\begin{array}{c}I\\ Q\\ U\\ r\end{array}\right]={\left(\frac{1}{2}\left[\begin{array}{cccc}\mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_0& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_0& 2\\ \mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_1& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_1& 2\\ \mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_2& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_2& 2\\ 2\mathrm{\ρ}& 0& 0& 0\end{array}\right]\right)}^{-1}\left[\begin{array}{c}{I}_0\\ I_1\\ I_2\\ I_{NP}\end{array}\right]---\left(15\right)$

In formula, θ₀、θ₁、θ₂It is respectively three preposition polaroids of analyzing passage angle through direction with horizontal direction, I₀、 I₁、I₂It is respectively θ₀、θ₁、θ₂The irradiance value that analyzing channel image pixel grey scale obtains through conversion, I_NPFor intensity channel image slices The irradiance value that element gray scale obtains through conversion；τ₁、τ₂Represent that the energy of preposition polaroid principal direction and orthogonal direction thereof passes through respectively Rate；ρ represents the energetic transmittance of polaroid back-end optical system, can be taken as when being concerned only with the relative size of stokes parameter It it is not the arbitrary value of 0 between 0～1；I, Q, U represent the strength component of incident radiation Stokes vector, level/vertical curve respectively Deviatoric component and+45 °/-45 ° line deviatoric components, r represents the reflected radiation of preposition polaroid and self radiates.

So far, the correction to stokes parameter is completed.

It is to be appreciated that the foregoing is only the specific embodiment of the present invention, the protection being not intended to limit the present invention Scope, all within the spirit and principles in the present invention, any modification, equivalent substitution and improvement etc. done, should be included in this Within bright protection domain.

Claims (8)

1. the radiation correction method of a preposition polaroid type infrared polarization imaging system, it is characterised in that: first, to removing inspection The infrared imaging system of mechanism partially carries out the demarcation of gradation of image irradiance mapping relations；Then, use infrared polarization imaging system System obtains Same Scene analyzing passage and the gray level image of intensity channel, the demarcation relation obtained according to the matching gray scale to gathering Image carries out the conversion from gray scale to irradiance；Finally, according to preposition polaroid type infrared polarization imaging system analyzing link Muller matrix (Mueller Matrix) solve stokes parameter (Stokes parameters) and polaroid reflected radiation and Self radiation, completes the correction to stokes parameter.

2. the radiation correction method of a preposition polaroid type infrared polarization imaging system, it is characterised in that: comprise the steps,

Step 1, carries out gradation of image irradiance mapping relations and demarcates the infrared imaging system removing analyzing mechanism；

Step 2, uses infrared polarization imaging system to obtain Same Scene analyzing passage and the gray level image of intensity channel, described Intensity channel refers to not install analyzing mechanism thus directly obtains the imaging band of scene radiation；Obtain according to matching in step 1 Demarcation relation to gather gray level image carry out the conversion from gray scale to irradiance；And according to preposition polaroid type infrared polarization The Muller matrix of imaging system analyzing mechanism solves stokes parameter and polaroid reflected radiation and self radiation, completes this The correction of lentor parameter.

The radiation correction method of a kind of preposition polaroid type infrared polarization imaging system the most as claimed in claim 1, its feature It is: described step 1 implementation method is,

Step 1.1, first, uses infrared imaging system to be calibrated to obtain face type blackbody radiation source infrared ash at different temperatures Degree image；

Under room temperature environment, placed side type blackbody radiation source beyond 10 times of focal lengths of infrared imaging system dead ahead to be calibrated, by black Temperature excursion is set to comprise the Regular temperature ranges of thermal imaging system photographed scene, the preferred 298.15K of temperature range～ 393.15K, interval sampling temperature value, and use infrared imaging system to be calibrated to shoot one group of black body radiation source images clearly；

Step 1.2, matching gradation of image irradiance mapping curve, i.e. complete the gradation of image irradiation of infra-red thermal imaging system Degree mapping relations are demarcated；

Calculation procedure 1.1 is often organized image blackbody radiation source and occupies the average gray of part, and according to blackbody radiation emission rate and Planck (Plank) formula calculates the blackbody radiation source radiant exitance in imaging system response wave band；Afterwards according to calculating number According to matching gradation of image black body radiation emittance mapping relations curve, i.e. complete the gradation of image spoke of infra-red thermal imaging system Illumination mapping relations are demarcated.

The radiation correction method of a kind of preposition polaroid type infrared polarization imaging system the most as claimed in claim 2 or claim 3, it is special Levy and be: described step 1.2 concrete methods of realizing is,

Part is occupied according to black matrix heat picture average gray computing formula (1) calculation procedure 1.1 often organizes image blackbody radiation source Average gray,

$\stackrel{\‾}{G}=\frac{\underset{A}{\mathrm{\Σ}}G}{\underset{A}{\mathrm{\Σ}}1}---\left(1\right)$

In formula,For boldface average gray, G is gradation of image, and A is the pixel region that in image, black matrix occupies；

The blackbody radiation source radiation outgoing in imaging system response wave band is calculated according to black body radiation emittance computing formula (2) Degree,

$M={\mathrm{\ϵ}}_{BB}\underset{{\mathrm{\λ}}_1}{\overset{{\mathrm{\λ}}_2}{\∫}}\[\frac{c_1}{{\mathrm{\λ}}^5}\frac{1}{\exp (c_2/\mathrm{\λ}T)}-1\]d\mathrm{\λ}---\left(2\right)$

In formula, M is the face type blackbody radiation source radiant exitance in imaging system response wave band；ε_BBRadiation for blackbody radiation source Emissivity, λ₁、λ₂It is respectively lower limit wavelength and the upper limit, the c of imaging system response wave band₁、c₂Often it is respectively first, second radiation Number；

To the black matrix heat picture average gray calculated according to formula (1) and the black matrix that calculates according to formula (2) in imaging system The radiant exitance of system response wave band is fitted, and matched curve form is formula (3),

$\stackrel{\‾}{G}=a\×M^{\mathrm{\γ}}+b---\left(3\right)$

In formula, a, b are respectively gain and biasing coefficient, and γ is for characterizing the non-linear effect between output signal and input radiation amount Should.

The radiation correction method of a kind of preposition polaroid type infrared polarization imaging system the most as claimed in claim 4, its feature It is: the approximating method described in step 1.2 is nonlinear least square method or trust region method.

6. for the radiation correction method of Single-channel Rolling polaroid type infrared polarization imaging system, it is characterised in that: include as Lower step,

Step 1, carries out image ash to the Single-channel Rolling polaroid type infrared polarization imaging system after removing preposition polaroid Degree irradiance mapping relations are demarcated；

Step 1.1, first, uses the Single-channel Rolling polaroid type infrared polarization imaging system after removing preposition polaroid to obtain Face type blackbody radiation source infrared hybrid optical system at different temperatures；

Single-channel Rolling polaroid type infrared polarization imaging system dead ahead 10 under room temperature environment, after removing preposition polaroid Placed side type blackbody radiation source beyond times focal length, is set to comprise the conventional temperature of thermal imaging system photographed scene by blackbody temperature excursion Degree scope, preferred 298.15K～393.15K of temperature range, interval sampling temperature value, and use infrared imaging system to be calibrated to clap Take the photograph one group of black body radiation source images clearly；Described interval sampling is preferably every 5K one temperature value of sampling；

Step 1.2, matching gradation of image irradiance mapping curve, i.e. complete the gradation of image irradiation of infra-red thermal imaging system Degree mapping relations are demarcated；

Calculation procedure 1.1 is often organized image blackbody radiation source and occupies the average gray of part, and according to blackbody radiation emission rate and Planck formula calculates the blackbody radiation source radiant exitance in imaging system response wave band；Afterwards according to calculating data fitted figure As gray scale black body radiation emittance mapping relations curve, the gradation of image irradiance i.e. completing infra-red thermal imaging system maps Relation is demarcated；

It is directly proportional owing to radiant exitance receives illumination to detector, replaces irradiance by radiant exitance below；

Part is occupied according to black matrix heat picture average gray computing formula (4) calculation procedure 1.1 often organizes image blackbody radiation source Average gray,

$\stackrel{\‾}{G}=\frac{\underset{A}{\mathrm{\Σ}}G}{\underset{A}{\mathrm{\Σ}}1}---\left(4\right)$

In formula,For boldface average gray, G is gradation of image, and A is the pixel region that in image, black matrix occupies；

The blackbody radiation source radiation outgoing in imaging system response wave band is calculated according to black body radiation emittance computing formula (5) Degree,

$M={\mathrm{\ϵ}}_{BB}\underset{{\mathrm{\λ}}_1}{\overset{{\mathrm{\λ}}_2}{\∫}}\[\frac{c_1}{{\mathrm{\λ}}^5}\frac{1}{\exp (c_2/\mathrm{\λ}T)}-1\]d\mathrm{\λ}---\left(5\right)$

In formula, M is the face type blackbody radiation source radiant exitance in imaging system response wave band；ε_BBRadiation for blackbody radiation source Emissivity, λ₁、λ₂It is respectively lower limit wavelength and the upper limit, the c of imaging system response wave band₁、c₂Often it is respectively first, second radiation Number；

To the black matrix heat picture average gray calculated according to formula (4) and the black matrix that calculates according to formula (5) in imaging system The radiant exitance of system response wave band is fitted, and matched curve form is formula (6),

$\stackrel{\‾}{G}=a\×M^{\mathrm{\γ}}+b---\left(6\right)$

In formula, a, b are respectively gain and biasing coefficient, and γ is for characterizing the non-linear effect between output signal and input radiation amount Should；

Approximating method described in step 1.2 can be nonlinear least square method, trust region method etc.；

Step 2, uses Single-channel Rolling polaroid type infrared polarization imaging system photographed scene, obtains the strong of same static scene Degree passage and the gray level image of analyzing passage；Polaroid is not installed when gathering intensity channel image, directly obtains from scene Incident radiation；Installing polaroid when gathering analyzing channel image, and altogether need to gather three times, before gathering for three times, rotation is preposition partially Shake sheet, makes polaroid pass through direction and is followed successively by θ with horizontal direction angle₀、θ₁、θ₂, three angles are different；Reflect according to demarcation Penetrate relational expression (6) and gradation of image is scaled irradiance；For in the analyzing channel image after conversion and intensity channel image All pixels carry out computing according to formula (7), solve the reflection spoke of correct incident radiation stokes parameter and polaroid Penetrate and self radiation:

$\left[\begin{array}{c}I\\ Q\\ U\\ r\end{array}\right]={\left(\frac{1}{2}\left[\begin{array}{cccc}\mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_0& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_0& 2\\ \mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_1& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_1& 2\\ \mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_2& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_2& 2\\ 2\mathrm{\ρ}& 0& 0& 0\end{array}\right]\right)}^{-1}\left[\begin{array}{c}{I}_0\\ I_1\\ I_2\\ I_{NP}\end{array}\right]---\left(7\right)$

In formula, I₀、I₁、I₂It is respectively θ₀、θ₁、θ₂The irradiance value that analyzing channel image pixel grey scale obtains through conversion, I_NPFor by force The irradiance value that degree channel image pixel grey scale obtains through conversion；τ₁、τ₂Represent preposition polaroid principal direction and orthogonal side thereof respectively To energetic transmittance；ρ represents the energetic transmittance of polaroid back-end optical system, when being concerned only with the relative of stokes parameter Can be taken as during size between 0～1 be not 0 arbitrary value；I, Q, U represent that the intensity of incident radiation Stokes vector is divided respectively Amount, level/vertical curve deviatoric component and+45 °/-45 ° line deviatoric components, r represents reflected radiation and self spoke of preposition polaroid Penetrate；

So far, the correction to stokes parameter is completed.

7. fix the radiation correction method of polaroid type infrared polarization imaging system for Single-channel Rolling wave plate, its feature exists In: comprise the steps,

Step 1, fixes polaroid type infrared polarization imaging system to the Single-channel Rolling wave plate after removing wave plate and preposition polaroid System carries out gradation of image irradiance mapping relations and demarcates；

Step 1.1, first, uses the Single-channel Rolling wave plate after removing wave plate and preposition polaroid to fix polaroid type infrared partially Imaging system of shaking obtains face type blackbody radiation source infrared hybrid optical system at different temperatures；

Under room temperature environment, the Single-channel Rolling wave plate after removing wave plate and preposition polaroid is fixed polaroid type infrared polarization and is become As placed side type blackbody radiation source beyond 10 times of focal lengths of system dead ahead, blackbody temperature excursion is set to comprises thermal imaging system and claps Take the photograph the Regular temperature ranges of scene, preferred 298.15K～393.15K of temperature range, interval sampling temperature value, and use to be calibrated Infrared imaging system shoots one group of black body radiation source images clearly；Described interval sampling is preferably every 5K one temperature of sampling Value；

Step 1.2, matching gradation of image irradiance mapping curve, i.e. complete the gradation of image irradiation of infra-red thermal imaging system Degree mapping relations are demarcated；

Calculation procedure 1.1 is often organized image blackbody radiation source and occupies the average gray of part, and according to blackbody radiation emission rate and Planck formula calculates the blackbody radiation source radiant exitance in imaging system response wave band；Afterwards according to calculating data fitted figure As gray scale black body radiation emittance mapping relations curve, the gradation of image irradiance i.e. completing infra-red thermal imaging system maps Relation is demarcated；

It is directly proportional owing to radiant exitance receives illumination to detector, replaces irradiance by radiant exitance below；

Part is occupied according to black matrix heat picture average gray computing formula (8) calculation procedure 1.1 often organizes image blackbody radiation source Average gray,

$\stackrel{\‾}{G}=\frac{\underset{A}{\mathrm{\Σ}}G}{\underset{A}{\mathrm{\Σ}}1}---\left(8\right)$

In formula,For boldface average gray, G is gradation of image, and A is the pixel region that in image, black matrix occupies；

The blackbody radiation source radiation outgoing in imaging system response wave band is calculated according to black body radiation emittance computing formula (9) Degree,

$M={\mathrm{\ϵ}}_{BB}\underset{{\mathrm{\λ}}_1}{\overset{{\mathrm{\λ}}_2}{\∫}}\[\frac{c_1}{{\mathrm{\λ}}^5}\frac{1}{\exp (c_2/\mathrm{\λ}T)}-1\]d\mathrm{\λ}---\left(9\right)$

In formula, M is the face type blackbody radiation source radiant exitance in imaging system response wave band；ε_BBRadiation for blackbody radiation source Emissivity, λ₁、λ₂It is respectively lower limit wavelength and the upper limit, the c of imaging system response wave band₁、c₂Often it is respectively first, second radiation Number；

To the black matrix heat picture average gray calculated according to formula (8) and the black matrix that calculates according to formula (9) in imaging system The radiant exitance of system response wave band is fitted, and matched curve form is formula (10),

$\stackrel{\‾}{G}=a\×M^{\mathrm{\γ}}+b---\left(10\right)$ In formula, a, b are respectively gain and biasing system Number, γ is for characterizing the nonlinear effect between output signal and input radiation amount；

Step 2, uses Single-channel Rolling wave plate to fix polaroid type infrared polarization imaging system photographed scene, obtains same static state The intensity channel of scene and the gray level image of analyzing passage；Wave plate and polaroid are not installed, directly when gathering intensity channel image Obtain the incident radiation from scene；Installing wave plate and polaroid when gathering analyzing channel image, wherein, polaroid passes through direction With horizontal direction parallel, and altogether need to gather four times, rotate quarter wave plates before gathering for four times, make wave plate quick shaft direction and level Angular separation is followed successively by θ₀、θ₁、θ₂、θ₃, four angles are different；According to demarcating mapping relations formula (10), gradation of image is changed Calculate as irradiance；Analyzing channel image after conversion and all pixels in intensity channel image are carried out according to formula (11) Computing, solves correct incident radiation stokes parameter and the reflected radiation of polaroid and self radiates:

$\left[\begin{array}{c}I\\ Q\\ U\\ V\\ r\end{array}\right]={\left(\frac{1}{2}\left[\begin{array}{ccccc}{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)\mathrm{\ρ}& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2){\mathrm{\ρcos}}^{2}2{\mathrm{\θ}}_0& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_0\cos 2{\mathrm{\θ}}_0& -{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_0& 2\\ {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)\mathrm{\ρ}& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2){\mathrm{\ρcos}}^{2}2{\mathrm{\θ}}_1& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_1\cos 2{\mathrm{\θ}}_1& -{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_1& 2\\ {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)\mathrm{\ρ}& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2){\mathrm{\ρcos}}^{2}2{\mathrm{\θ}}_2& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_2\cos 2{\mathrm{\θ}}_2& -{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_2& 2\\ {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)\mathrm{\ρ}& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2){\mathrm{\ρcos}}^{2}2{\mathrm{\θ}}_3& {\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_3\cos 2{\mathrm{\θ}}_3& -{\mathrm{\τ}}_{wp}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\mathrm{\ρ}\sin 2{\mathrm{\θ}}_3& 2\\ 2\mathrm{\ρ}& 0& 0& 0& 0\end{array}\right]\right)}^{-1}\left[\begin{array}{c}{I}_0\\ I_1\\ I_2\\ I_3\\ I_{NP}\end{array}\right]---\left(11\right)$

In formula, I₀、I₁、I₂、I₃It is respectively θ₀、θ₁、θ₂、θ₃The irradiance value that analyzing channel image pixel grey scale obtains through conversion, I_NP The irradiance value obtained through conversion for intensity channel image pixel gray level；τ_wpRepresent the energetic transmittance of quarter wave plate, τ₁、τ₂Point Do not represent preposition polaroid principal direction and the energetic transmittance of orthogonal direction thereof；ρ represents the energy of polaroid back-end optical system Transmitance, can be taken as when being concerned only with the relative size of stokes parameter between 0～1 be not 0 arbitrary value；I, Q, U, V divide Not Biao Shi the strength component of incident radiation Stokes vector, level/vertical curve deviatoric component ,+45 °/-45 ° line deviatoric components and Dextrorotation/left-handed round deviatoric component；R represents the reflected radiation of preposition polaroid and self radiates；

So far, the correction to stokes parameter is completed.

8. for the radiation correction method of real-time four-way infrared polarization imaging system, it is characterised in that: comprise the steps,

Step 1, the thermal infrared imager using four imaging bands carries out gradation of image irradiance mapping relations respectively and demarcates； The concrete demarcating steps of the thermal infrared imager of each imaging band is:

Step 1.1, first, uses thermal infrared imager to obtain face type blackbody radiation source infrared hybrid optical system at different temperatures；

Under room temperature environment, placed side type blackbody radiation source beyond 10 times of focal lengths of thermal infrared imager dead ahead to be calibrated, by black matrix Range of temperature is set to comprise the Regular temperature ranges of thermal imaging system photographed scene, the preferred 298.15K of temperature range～ 393.15K, interval sampling temperature value, and use infrared imaging system to be calibrated to shoot one group of black body radiation source images clearly； Described interval sampling is preferably every 5K one temperature value of sampling；

Step 1.2, matching gradation of image irradiance mapping curve, the gradation of image irradiance i.e. completing thermal infrared imager reflects Relation of penetrating is demarcated；

Calculation procedure 1.1 is often organized image blackbody radiation source and occupies the average gray of part, and according to blackbody radiation emission rate and Planck formula calculates the blackbody radiation source radiant exitance in imaging system response wave band；Afterwards according to calculating data fitted figure As gray scale black body radiation emittance mapping relations curve, i.e. complete the gradation of image irradiance mapping relations of thermal infrared imager Demarcate；

It is directly proportional owing to radiant exitance receives illumination to detector, replaces irradiance by radiant exitance below；

Part is occupied according to black matrix heat picture average gray computing formula (12) calculation procedure 1.1 often organizes image blackbody radiation source Average gray,

$\stackrel{\‾}{G}=\frac{\underset{A}{\mathrm{\Σ}}G}{\underset{A}{\mathrm{\Σ}}1}---\left(12\right)$

In formula,For boldface average gray, G is gradation of image, and A is the pixel region that in image, black matrix occupies；

The blackbody radiation source radiation outgoing in imaging system response wave band is calculated according to black body radiation emittance computing formula (13) Degree,

$M={\mathrm{\ϵ}}_{BB}\underset{{\mathrm{\λ}}_1}{\overset{{\mathrm{\λ}}_2}{\∫}}\[\frac{c_1}{{\mathrm{\λ}}^5}\frac{1}{\exp (c_2/\mathrm{\λ}T)}-1\]d\mathrm{\λ}---\left(13\right)$

In formula, M is the face type blackbody radiation source radiant exitance in imaging system response wave band；ε_BBRadiation for blackbody radiation source Emissivity, λ₁、λ₂It is respectively lower limit wavelength and the upper limit, the c of imaging system response wave band₁、c₂Often it is respectively first, second radiation Number；

To the black matrix heat picture average gray calculated according to formula (12) and the black matrix that calculates according to formula (13) in imaging The radiant exitance of system response wave band is fitted, and matched curve form is formula (14),

$\stackrel{\‾}{G}=a\×M^{\mathrm{\γ}}+b---\left(14\right)$

In formula, a, b are respectively gain and biasing coefficient, and γ is for characterizing the non-linear effect between output signal and input radiation amount Should；

Step 2, uses real-time four-way infrared polarization imaging system photographed scene, installed polaroid respectively by front end three The intensity imaging passage of polarization imaging passage and front end no polarization sheet obtains analyzing image and the intensity image of Same Scene；According to In step 1, respective channel gradation of image is scaled spoke by demarcation mapping relations formula (14) of the thermal infrared imager that each passage uses Illumination；According to formula (15), computing is carried out for the analyzing channel image after conversion and all pixels in intensity channel image, Solve correct incident radiation stokes parameter and the reflected radiation of polaroid and self radiate:

$\left[\begin{array}{c}I\\ Q\\ U\\ r\end{array}\right]={\left(\frac{1}{2}\left[\begin{array}{cccc}\mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_0& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_0& 2\\ \mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_1& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_1& 2\\ \mathrm{\ρ}({\mathrm{\τ}}_1+{\mathrm{\τ}}_2)& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\cos 2{\mathrm{\θ}}_2& \mathrm{\ρ}({\mathrm{\τ}}_1-{\mathrm{\τ}}_2)\sin 2{\mathrm{\θ}}_2& 2\\ 2\mathrm{\ρ}& 0& 0& 0\end{array}\right]\right)}^{-1}\left[\begin{array}{c}{I}_0\\ I_1\\ I_2\\ I_{NP}\end{array}\right]---\left(15\right)$

In formula, θ₀、θ₁、θ₂It is respectively three preposition polaroids of analyzing passage angle through direction with horizontal direction, I₀、I₁、I₂ It is respectively θ₀、θ₁、θ₂The irradiance value that analyzing channel image pixel grey scale obtains through conversion, I_NPFor intensity channel image pixel ash Spend the irradiance value obtained through conversion；τ₁、τ₂Represent preposition polaroid principal direction and the energetic transmittance of orthogonal direction thereof respectively；ρ Represent the energetic transmittance of polaroid back-end optical system, can be taken as 0～1 when being concerned only with the relative size of stokes parameter Between be not 0 arbitrary value；I, Q, U represent that the strength component of incident radiation Stokes vector, level/vertical curve divide partially respectively Amount and+45 °/-45 ° line deviatoric components, r represents the reflected radiation of preposition polaroid and self radiates.

So far, the correction to stokes parameter is completed.