CN102879103A - Method for correcting error of polarization detection device - Google Patents

Abstract

The invention discloses a method for correcting an error of a polarization detection device. The polarization detection device comprises a phase retarder, an analyzer and a photoelectric detector which are sequentially arranged along an optical axis of the device system, wherein the output of the photoelectric detector is connected with a signal processing system; and the linearly polarized light with the Stokes parameter of (1, 1, 0, 0) enters the polarization detection device. The method comprises the following steps of: setting the angle of a transparent shaft of the analyzer to be 0 and performing measurement for the first time to obtain a first measurement error of the normalized Stokes parameter; setting the angle of the transparent shaft of the analyzer to be 45 degrees and performing measurement for the second time to obtain a second measurement error of the normalized Stokes parameter; and solving the phase retardation error of the phase retarder, the fast axis angle error and the transparent shaft angle error of the analyzer in the polarization detection device so as to realize error correction. According to the method, the device error in the polarization detection device can be measured under the condition that the polarization detection device does not need to be detached, so that the device error is corrected.

Description

The bearing calibration of device for testing polarization device error

Technical field

The present invention relates to device for testing polarization, particularly a kind of bearing calibration of device for testing polarization device error.

Background technology

The progress of semiconductor fabrication is always with the power that is reduced to of the increase of the reducing of exposure wavelength, numerical aperture of projection objective and photoetching process factor k1.Recent years, immersion lithography has obtained fast development.In immersion lithography, adopt certain liquid filling between the photoresist on the last a slice eyeglass of object lens and the silicon chip, the numerical aperture of projection objective is significantly improved.When the numerical aperture of projection objective near 0.8 or when larger, the polarization state of illumination light is very important on the impact of optical patterning.Adopting suitable polarized illumination is a kind of strong method that improves image contrast in the large-numerical aperture situation.For different lighting systems, polarization illumination requires to form different linear polarization, such as x direction polarized light, y direction polarized light, radial polarisation light, tangential polarization light etc.

When using polarized illumination, there is many factors polarisation of light attitude in the illuminator of projection aligner.Most importantly the intrinsic birefringence of optical material and stress birefrin reduce the polarisation of light degree.In addition, the polarization characteristic of optical thin film, light also can affect the polarisation of light attitude in reflection and the refraction at interface.Therefore, in polarized-light lighting system, owing to the needs of Polarization Control, should detect in real time the polarization state of illumination light, and the rotating wave plate in the FEEDBACK CONTROL illuminator, the linearly polarized light output of high-polarization guaranteed.In addition, also need to carry out polarization illumination and detect dress school and the maintenance that is used for litho machine.Technology 1(Jap.P.: Te Open 2005-005521 formerly) a kind of polarization parameter pick-up unit that utilizes the rotatable phase delayer has been proposed.Fig. 3 is the schematic diagram of illumination iris polarization parameter pick-up unit in the projection aligner that proposes of technology 1 formerly.As shown in Figure 3, this polarization parameter pick-up unit comprises pinhole mask 10, transform lens group 20, phase delay device 2 and driver 6 thereof, analyzer 3, photodetector 4 and signal processing system 5.Illuminating bundle by the pin hole 101 on the pinhole mask 10 after, become parallel beam through transform lens group 20.This parallel beam is as incident beam 1, successively by being surveyed by photodetector 4 behind phase delay device 2 and the analyzer 3.

Described pinhole mask 10 place projection aligner the mask face or near, perhaps with the plane of mask face conjugation or neighbouring (the silicon chip face or near, perhaps with the plane of silicon chip face conjugation or near).

When utilizing device in the technology 1 formerly to measure, the systematic optical axis rotation of phase delay device 2 winding apparatus, utilize formerly technology 1 and formerly technology 2(Jap.P.: Te Open 2006-179660) in data processing method the electric signal of photodetector output is processed, can obtain the Stokes' parameter of incident beam.But the phase delay device of this device and analyzer all are operated in the deep ultraviolet wave band, are difficult to make desirable device according to design objective at this wave band, therefore can produce the Stokes' parameter measuring error.

For this reason, formerly technology 2 has proposed not to be subjected to the impact of phase delay device and analyzer correlated error, the method for high-precision measurement polarization parameter.The method is to measure the polarization characteristic of each device before consisting of device for testing polarization with wave plate and analyzer, comprises that light transmission shaft direction, the extinction ratio of the interior distribution of face, quick shaft direction and the analyzer of retardation of wave plate distributes.But the method still can not be measured the positioning error of the direction of the quick shaft direction of the phase delay device that is installed in device for testing polarization and analyzer light transmission shaft, can't eliminate the impact of angle orientation error on measuring of the device that consists of device for testing polarization.Technology 3(Chinese patent formerly: 201010268324.5) proposed a kind of measuring method of apparatus error in polarization detection device, but the method need to obtain theoretical curved surface by emulation, and then find corresponding error point to determine the device error according to the polarization azimuth error of twice measurement and degree of polarization error at theoretical curved surface, be similar to the method for enquiry form, determine that the process of error is more loaded down with trivial details.

Summary of the invention

The object of the invention is to replenish above-mentioned the deficiencies in the prior art, a kind of bearing calibration of device for testing polarization device error is provided.The light transmission shaft angular error of phase-delay quantity error, fast shaft angle degree error and analyzer by the phase delay device that measures in the manufacture process and occur when consisting of device for testing polarization is the device error of recoverable device for testing polarization according to the result who records.

Technical solution of the present invention is as follows:

A kind of bearing calibration of device for testing polarization device error, the formation of described device for testing polarization comprises the phase delay device that sets gradually along the apparatus system optical axis, analyzer and photodetector, the output of this photodetector connects signal processing system, but described phase delay device is the rotation of winding apparatus systematic optical axis under the driving of driver, incident beam is parallel to systematic optical axis and is incident to described phase delay device and analyzer, and by described photodetector detection, the electric signal of this photodetector output is sent into described signal processing system and is carried out the data processing, it is characterized in that:

When utilizing described device for testing polarization to carry out Polarization Detection, the light transmission shaft angle of the phase-delay quantity of phase delay device, fast axle initial angle and analyzer is known, as initial parameter;

Described incident beam is the horizontal direction linearly polarized light, and its Stokes' parameter is (S ₀₀, S ₀₁, S ₀₂, S ₀₃)=(1,1,0,0);

Original state when measuring for the first time is that the light transmission shaft angle of described analyzer is 0 degree, carries out measuring for the first time the measuring error first time of normalization Stokes' parameter;

Original state when measuring for the second time is that the light transmission shaft angle of described analyzer is 45 degree, carries out measuring for the second time the measuring error second time of normalization Stokes' parameter;

Described signal processing system is processed the normalization Stokes' parameter measuring error that obtains for twice, obtain afterwards as calculated the light transmission shaft angular error of the phase-delay quantity error of phase delay device in the device for testing polarization, fast shaft angle degree error and analyzer, can the correcting device error according to the result who records.

Its concrete aligning step of the bearing calibration of described device for testing polarization device error is as follows:

1. the original state of measuring for the first time is set: the system optical axis of setting up departments is the z axle of Cartesian coordinates, the forward of z axle is the light beam working direction, the plane vertical with the z axle is the xy plane, take the polarization direction of the horizontal direction linearly polarized light of incident as the x direction of principal axis, angle between the fast axle of x axle positive dirction and phase delay device is fast shaft angle degree θ, angle between x axle positive dirction and the analyzer light transmission shaft is the light transmission shaft angle [alpha], the phase-delay quantity of phase delay device is δ, take the design parameter of described phase delay device and analyzer as benchmark, adjust the initial fast shaft angle degree θ 0 of described phase delay device, the light transmission shaft angle of described analyzer is 0 degree, and sets the original state of this state for measuring for the first time;

2. measure for the first time: utilize the described phase delay device rotation of driver drives, described photodetector is surveyed light signal and output electrical signals, described electric signal obtains normalization Stokes' parameter (1, the S of incident beam after described signal processing system data are processed ₁₁, S ₁₂, S ₁₃), with known incident beam Stokes' parameter (S ₀₀, S ₀₁, S ₀₂, S ₀₃)=(1,1,0,0) compare, obtain the S of normalization Stokes' parameter ₁₁And S ₁₂Measuring error is for the first time:

ΔS ₁₁=S ₁₁-S ₀₁=S ₁₁-1，ΔS ₁₂=S ₁₂-S ₀₂=S ₁₂-0=S ₁₂；

3. the original state of measuring for the second time is set: the initial angle light transmission shaft angle identical, described analyzer of the fast shaft angle degree of adjusting described phase delay device when measuring for the first time is 45 degree, and sets this state and be the original state of measurement for the second time;

4. measure for the second time: the described phase delay device rotation of described driver drives, described photodetector is surveyed light signal and output electrical signals, described electric signal carries out data through described signal processing system to described electric signal to be processed, obtain normalization Stokes' parameter (1, the S of incident beam ₂₁, S ₂₂, S ₂₃), compare with known incident beam Stokes' parameter (1,1,0,0), obtain normalization Stokes' parameter S ₂₁The measuring error second time be:

ΔS ₂₁=S ₂₁-S ₀₁=S ₂₁-1；

5. acquisition device error: the light transmission shaft angular error Δ α of the phase-delay quantity error delta δ of phase delay device, fast shaft angle degree error delta θ 0 and analyzer is with the first time of normalization Stokes' parameter, exist following the relation for the second time in the device for testing polarization between the measuring error: 2 Δs δ=Δ S ₁₁=S ₁₁-1,2 Δ α-4 Δ θ ₀=Δ S ₁₂=S ₁₂, 2 Δ α-2 Δ θ ₀+ Δ δ=Δ S ₂₁=S ₂₁-1, try to achieve Δ δ, Δ θ ₀With Δ α;

6. device error correction: when using described device for testing polarization to carry out Polarization Detection, for initial parameter δ, θ ₀With the value of α, utilize respectively Δ δ+δ, Δ θ ₀+ θ ₀Replace with the value of Δ α+α, namely realize the correction of the light transmission shaft angular error of the phase-delay quantity error of phase delay device, fast axle initial angle error and analyzer.

The described phase delay device system for winding of described driver drives optical axis at the uniform velocity rotates, perhaps by driving the position of at least four different angles between fast axle that the phase delay device rotation can arrange phase delay device and the described analyzer light transmission shaft.

The present invention has been owing to having adopted technique scheme, compares with technology formerly, has the following advantages and good effect:

Compare with technology 2 formerly, the present invention is in the situation that need not to dismantle the device for testing polarization device, by the normalization Stokes' parameter of twice measurement incident beam, can measure the manufacturing of phase delay device and analyzer and the error that the location forms, finish the device error correction of device for testing polarization.Compare with technology 3 formerly, the present invention is simple, the link such as avoided loaded down with trivial details emulation and table look-up.

Description of drawings

Fig. 1 is the related device for testing polarization schematic diagram of the bearing calibration of device for testing polarization device error of the present invention.

Fig. 2 is the process flow diagram of correcting device error.

Fig. 3 is the schematic diagram of illumination iris polarization parameter pick-up unit in the existing projection aligner.

Embodiment

The invention will be further described below in conjunction with embodiment and accompanying drawing, but should not limit protection scope of the present invention with this.

See also first Fig. 1, Fig. 1 is the related device for testing polarization schematic diagram of the bearing calibration of device for testing polarization device error of the present invention.As seen from Figure 1, the formation of the device for testing polarization that the present invention relates to comprises the phase delay device 2 that sets gradually along the apparatus system optical axis, analyzer 3 and photodetector 4, the output of this photodetector 4 connects signal processing system 5, but described phase delay device 2 is the rotation of winding apparatus systematic optical axis under the driving of driver 6, light beam is parallel to systematic optical axis and is incident to described phase delay device 2 and analyzer 3, and by described photodetector 4 detections, the electric signal of these photodetector 4 outputs is sent into described signal processing system 5 and is carried out the data processing, obtains the Stokes' parameter of incident beam 1.

The characteristics of the bearing calibration of device for testing polarization device error of the present invention are:

When utilizing described device for testing polarization to carry out Polarization Detection, the light transmission shaft angle of the phase-delay quantity of phase delay device, fast axle initial angle and analyzer is known, as initial parameter;

Described incident beam is the horizontal direction linearly polarized light, and its Stokes' parameter is (S ₀₀, S ₀₁, S ₀₂, S ₀₃)=(1,1,0,0);

Original state when measuring for the first time is that the fast shaft angle degree of described phase delay device 2 is that the light transmission shaft angle of unspecified angle, described analyzer 3 is 0 degree;

Original state when measuring for the second time is to measure on the basis of original state for the first time, rotates light transmission shaft angle 45 degree of described analyzer 3;

Data are carried out in twice measurement process, obtain the device error, can realize the device error correction of device for testing polarization.

For the ease of the understanding of the present invention, about key concept of the present invention with according to being explained as follows:

The device error of described device for testing polarization comprises: the positioning error of quick shaft direction can be summed up as fast shaft angle degree error when the foozle between phase delay device 2 quick shaft directions and the design parameter and formation device for testing polarization; The phase-delay quantity of phase delay device 2 and the foozle between the design parameter, the phase-delay quantity error that the variation of the external environment such as quick shaft direction and the caused phase-delay quantity error of systematic optical axis off plumb positioning error and temperature causes when consisting of device for testing polarization can be summed up as the phase-delay quantity error; The axial positioning error of printing opacity can be summed up as the light transmission shaft angular error when light transmission shaft direction of analyzer 3 and the foozle between the design parameter and formation device for testing polarization.

Original state during described the measurement is before rotatable phase delayer 2 is measured, the residing position of light transmission shaft of the fast axle of phase delay device 2 and analyzer 3.

Described phase delay device 2 is for producing quarter-wave plate, electrooptic modulator or the light ball modulator of 90 degree phase delays.Phase delay device 2 is quarter-wave plate in the present embodiment.

Described driver 6 drives the angle multiple rotary that described phase delay device 2 system for winding optical axises at the uniform velocity rotate or the interval is fixing, perhaps by driving at least four different angle positions between fast axle that phase delay device 2 rotations can arrange phase delay device 2 and described analyzer 3 light transmission shafts.Driver 6 can drive phase delay device 2 system for winding optical axises and at the uniform velocity rotates in the present embodiment.

Analyzer 3 in the described device for testing polarization is 100% for the transmitance of the polarization direction linearly polarized light parallel with light transmission shaft in the ideal case; And with the transmitance of the linearly polarized light of this light transmission shaft perpendicular direction be 0.Definition is parallel to the light transmission shaft direction and is extinction coefficient p perpendicular to the ratio of the axial linear polarization light intensity of printing opacity transmitance, and ideally p be infinity.Analyzer 3 is polarizing prism in the present embodiment.

Described photodetector 4 is two-dimensional array detector or point probe.Photodetector 4 is point probe in the present embodiment.

Described signal processing system 5 utilize technology 1 formerly and formerly the data processing method in the technology 2 electric signal of photodetector 4 outputs is processed the Stokes' parameter of the incident beam 1 that output records.

Xyz coordinate system shown in definition Fig. 1, wherein the z axle is systematic optical axis, and the positive dirction of z axle is the light beam working direction, and the xy plane is the plane vertical with systematic optical axis.If the Stokes' parameter of incident beam is S=[S ₀, S ₁, S ₂, S ₃] ^T(upper right corner " T " representing matrix transposition).

Angle between definition x axle positive dirction and the quarter-wave plate fast axis is fast shaft angle degree θ, and its scope is-90 °≤θ≤90 °; Angle between definition x axle positive dirction and the polarizing prism light transmission shaft is the light transmission shaft angle [alpha], and its scope is-90 °≤α≤90 °.

The Muller matrix of the quarter-wave plate of described systematic optical axis rotation around device for testing polarization is:

$M\left(\mathrm{\&theta;}\right)=\left[\begin{array}{cccc}1,& 0,& 0,& 0\\ 0,& {\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^{2}2\mathrm{\&theta;}{+\sin }^{2}2\mathrm{\&theta;}\cos \mathrm{\&delta;},& \sin 2\mathrm{\&theta;}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&theta;}-\sin 2\mathrm{\&theta;}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&theta;}\cos \mathrm{\&delta;},& -\sin 2\mathrm{\&theta;}\sin \mathrm{\&delta;}\\ 0,& \sin 2\mathrm{\&theta;}\cos -\sin 2\mathrm{\&theta;}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&theta;sos\&delta;},& {\sin }^{2}2\mathrm{\&theta;}+{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^{2}2\mathrm{\&theta;}\cos \mathrm{\&delta;},& \cos 2\mathrm{\&theta;}\sin \mathrm{\&delta;}\\ 0,& \sin 2\mathrm{\&theta;}\sin \mathrm{\&delta;},& -\cos 2\mathrm{\&theta;}\sin \mathrm{\&delta;},& \cos \mathrm{\&delta;}\end{array}\right],---\left(1\right)$

Wherein, δ is the phase-delay quantity of quarter wave plate.

Extinction ratio is that p, light transmission shaft angle are that the Muller matrix of the analyzer of α is:

$P\left(\mathrm{\&alpha;}\right)=\left[\begin{array}{cccc}1,& \frac{p-1}{p+1}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;},& \frac{p-1}{p+1}\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}& 0\\ \frac{p-1}{p+1}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;},& {\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^{2}2\mathrm{\&alpha;}\frac{2\sqrt{p}}{p+1}{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^{2}2\mathrm{\&alpha;},& \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;}-\frac{2\sqrt{p}}{p+1}\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;}& 0\\ \frac{p-1}{p+1}\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;},& \mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;}-\frac{2\sqrt{p}}{p+1}\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;},& {\sin }^{2}2\mathrm{\&alpha;}+\frac{2\sqrt{p}}{p+1}{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2& 0\\ 0,& 0,& 0,& \frac{2\sqrt{p}}{p+1}\end{array}\right].---\left(2\right)$

Behind light beam process quarter wave plate to be measured and the analyzer, Stokes vector is S'=P (α) M (θ) S.Because the first row of Stokes vector represents the total intensity of light wave, the light intensity that photodetector can detect i.e. intensity level for this reason, so only be concerned about the first row numerical value of Stokes vector herein.

Measure about S ₀, S ₁, S ₂, S ₃The quaternary linear function be:

${S_0}^{\&prime;}\left(\mathrm{\&theta;}\right)=S_0+S_1\frac{p-1}{p+1}\{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;}+[{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^{2}2(\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)+{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^{2}2(\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)\cos \mathrm{\&delta;}]+\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}\sin 2(\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)\cos 2(\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)(1-\cos )\}$

$+S_2\frac{p-1}{p+1}\{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;}\sin 2(\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)\mathrm{sos}2(\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)(1-\cos \mathrm{\&delta;})+\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}[{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^{2}2(\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)+{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^{2}2(\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)\mathrm{sos\&delta;}\left]\right\}$

$+S_3\frac{p-1}{p+1}[\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}\cos 2(\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)-\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;}\sin (\mathrm{\&theta;}+{\mathrm{\&theta;}}_0)]\sin \mathrm{\&delta;},---\left(3\right)$

θ wherein ₀Initial (being the original state of quarter wave plate when not rotating) fast shaft angle degree for quarter wave plate.

During measurement, rotate quarter wave plate and change θ.With S ₀' as the function of θ, and with its fourier expansion:

${S_0}^{\&prime;}\left(\mathrm{\&theta;}\right)=\frac{a_0}{2}+\underset{n}{\mathrm{\&Sigma;}}(a_n\cos \mathrm{n\&theta;}+b_n\sin \mathrm{n\&theta;}),---\left(4\right)$

Obtain respectively a ₀, a ₂, b ₂, a ₄And b ₄:

$\frac{a_0}{2}=S_0+\frac{p-1}{p+1}({\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_1\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;}+{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_2\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}){\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2},---\left(5\right)$

$a_2=\frac{p-1}{p+1}{\mathrm{<figure-callout\; id="3"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_3\sin 2(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0)\sin \mathrm{\&delta;},---\left(6\right)$

${\mathrm{<figure-callout\; id="2"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_2=-\frac{p-1}{p+1}{\mathrm{<figure-callout\; id="3"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_3\cos 2(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0)\sin \mathrm{\&delta;},---\left(7\right)$

$a_4=\frac{p-1}{p+1}[{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_1\cos 2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0)-{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_2\sin 2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0)]{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2},---\left(8\right)$

${\mathrm{<figure-callout\; id="4"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_4=\frac{p-1}{p+1}[{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_1\sin 2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0)+{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_2\cos 2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0)]{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}.---\left(9\right)$

The a that utilization obtains ₀, a ₂, b ₂, a ₄And b ₄, 4 the Stokes' parameter Ss corresponding with polarization state light beam to be measured that obtain by Amplitude Comparison ₀, S ₁, S ₂, S ₃For:

$S_0=\frac{a_0}{2}-{\mathrm{<figure-callout\; id="2"\; label="ctg"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">ctg</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}[a_4\cos 4(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0)+{\mathrm{<figure-callout\; id="4"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_4\sin 4(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0],---\left(10\right)$

${\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_1=\frac{p+1}{(p-1){\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}}[a_4\cos 2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0)+{\mathrm{<figure-callout\; id="4"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_4\sin 2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0)],---\left(11\right)$

$S_2\frac{p+1}{(p-1){\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}}[{\mathrm{<figure-callout\; id="4"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_4\cos 2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0)-a_4\sin 2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0),---\left(12\right)$

${\mathrm{<figure-callout\; id="3"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_3=\frac{-(p+1)b_2}{(p-1)\sin \mathrm{\&delta;}\cos 2(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0)}=\frac{(p+1)a_2}{(p-1)\sin \mathrm{\&delta;}\sin 2(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0)}.---\left(13\right)$

Can obtain the normalization Stokes' parameter is:

S ₀₀=1， (14)

$S_{10}=\frac{S_1}{S_0}=\frac{\frac{p+1}{(p-1){\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}}\sin [2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0)+\mathrm{\&phi;}]}{\frac{a_0}{2\sqrt{{a_4}^2+{{\mathrm{<figure-callout\; id="4"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_4}^2}}-{\mathrm{<figure-callout\; id="2"\; label="ctg"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">ctg</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}\sin [4(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0)+\mathrm{\&phi;}]},---\left(15\right)$

$S_{20}=\frac{S_2}{S_0}=\frac{\frac{p+1}{(p-1){\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}}\sin [2(\mathrm{\&alpha;}-{2\mathrm{\&theta;}}_0)+\mathrm{\&phi;}]}{\frac{a_0}{2\sqrt{{a_4}^2+{{\mathrm{<figure-callout\; id="4"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_4}^2}}-{\mathrm{<figure-callout\; id="2"\; label="ctg"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">ctg</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}\sin [4(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0)+\mathrm{\&phi;}]},---\left(16\right)$

$S_{30}=\frac{S_3}{S_0}=\frac{1}{\sqrt{{a_4}^2+{{\mathrm{<figure-callout\; id="4"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_4}^2}}\frac{\frac{-(p+1)b_2}{(p-1)\sin \mathrm{\&delta;}\cos 2(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0)}}{\frac{a_0}{2\sqrt{{a_4}^2+{{\mathrm{<figure-callout\; id="4"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_4}^2}}-{\mathrm{<figure-callout\; id="2"\; label="ctg"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">ctg</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}\sin [4(\mathrm{\&alpha;}-{\mathrm{\&theta;}}_0)+\mathrm{\&phi;}]}.---\left(17\right)$

Wherein

$\sqrt{{a_4}^2+{{\mathrm{<figure-callout\; id="4"\; label="b"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">b</figure-callout>}}_4}^2}$

$=\frac{p-1}{p+1}{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}\sqrt{{[{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_1\cos 2(\mathrm{\&alpha;}-2{\mathrm{\&theta;}}_0)-{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_2\sin 2(\mathrm{\&alpha;}-2{\mathrm{\&theta;}}_0)]}^2+{[{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_1\sin 2(\mathrm{\&alpha;}-2{\mathrm{\&theta;}}_0)+{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_2\cos 2(\mathrm{\&alpha;}-2{\mathrm{\&theta;}}_0)]}^2}.$

$=\frac{p-1}{p+1}{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\frac{\mathrm{\&delta;}}{2}\sqrt{{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_1^2+{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">S</figure-callout>}}_2^2}$

Be the phase-delay quantity δ that obtains quarter wave plate, the initial fast shaft angle degree θ of quarter wave plate ₀, analyzer light transmission shaft angle [alpha], analyzer the error in the normalization Stokes' parameter, introduced of extinction ratio p (〉=1000) equal error, utilize the expression formula of normalization Stokes' parameter, respectively to δ, θ ₀, α and p carry out differential, can try to achieve the phase-delay quantity error delta δ of quarter wave plate, initial fast shaft angle degree error delta θ ₀, analyzer light transmission shaft angular error Δ α, analyzer the systematic error in Stokes' parameter S10 and S20, introduced of extinction ratio error, can obtain:

$\frac{{\&PartialD;S}_{10}}{{\&PartialD;\mathrm{\&theta;}}_0}\&ap;2\cos \mathrm{\&Phi;}[2+\sin (2\mathrm{\&alpha;}+\mathrm{\&Phi;})]-2\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;},---\left(18\right)$

$\frac{{\&PartialD;S}_{10}}{\&PartialD;\mathrm{\&alpha;}}\&ap;\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">sin</figure-callout>}2\mathrm{\&alpha;}-2\cos \mathrm{\&Phi;}-\sin 2(\mathrm{\&alpha;}+\mathrm{\&Phi;}),---\left(19\right)$

$\frac{{\&PartialD;S}_{10}}{\&PartialD;\mathrm{\&delta;}}\&ap;\sin \mathrm{\&Phi;}[1+\sin (2\mathrm{\&alpha;}+\mathrm{\&Phi;})],---\left(20\right)$

$\frac{{\&PartialD;S}_{10}}{\&PartialD;p}\&ap;\frac{2\sin \mathrm{\&Phi;}}{{(p-1)}^2}\&ap;0.---\left(21\right)$

To obtaining behind the S20 differential:

$\frac{{\&PartialD;S}_{20}}{{\&PartialD;\mathrm{\&theta;}}_0}\&ap;2\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;}-2\sin \mathrm{\&Phi;}[2+\sin (2\mathrm{\&alpha;}+\mathrm{\&Phi;})],---\left(22\right)$

$\frac{{\&PartialD;S}_{20}}{\&PartialD;\mathrm{\&alpha;}}\&ap;2\sin \mathrm{\&Phi;}-\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA00002266719700011.png"\; state="\{\{state\}\}">cos</figure-callout>}2\mathrm{\&alpha;}-\cos 2(\mathrm{\&alpha;}+\mathrm{\&Phi;}),---\left(23\right)$

$\frac{{\&PartialD;S}_{20}}{\&PartialD;\mathrm{\&delta;}}\&ap;\cos \mathrm{\&Phi;}[1+\sin (2\mathrm{\&alpha;}+\mathrm{\&Phi;})],---\left(24\right)$

$\frac{{\&PartialD;S}_{20}}{\&PartialD;p}\&ap;\frac{2\cos \mathrm{\&Phi;}}{{(p-1)}^2}\&ap;0.---\left(25\right)$

Incident beam is the horizontal direction linearly polarized light, and its Stokes' parameter is (S ₀₀, S ₀₁, S ₀₂, S ₀₃)=(1,1,0,0), Φ=90 are spent at this moment.

When α=0 is spent, $\frac{{\&PartialD;S}_{10}}{{\&PartialD;\mathrm{\&theta;}}_0}\&ap;0,$ $\frac{{\&PartialD;S}_{10}}{\&PartialD;\mathrm{\&alpha;}}\&ap;0,$ $\frac{{\&PartialD;S}_{10}}{\&PartialD;\mathrm{\&delta;}}\&ap;2,$ $\frac{{\&PartialD;S}_{20}}{{\&PartialD;\mathrm{\&theta;}}_0}\&ap;-4,$ $\frac{{\&PartialD;S}_{20}}{\&PartialD;\mathrm{\&alpha;}}\&ap;2,$ $\frac{{\&PartialD;S}_{20}}{\&PartialD;\mathrm{\&delta;}}\&ap;0,$

Have

ΔS ₁₀₍₀₎S ₁₀₍₀₎-1=2Δδ， (26)

ΔS ₂₀₍₀₎=S ₂₀₍₀₎=2Δα-4Δθ ₀， (27)

When α=45 are spent, $\frac{{\&PartialD;S}_{10}}{{\&PartialD;\mathrm{\&theta;}}_0}\&ap;-2,$ $\frac{{\&PartialD;S}_{10}}{\&PartialD;\mathrm{\&alpha;}}\&ap;2,$ $\frac{{\&PartialD;S}_{10}}{\&PartialD;\mathrm{\&delta;}}\&ap;1,$ Therefore have

ΔS ₁₀₍₄₅₎=S ₁₀₍₄₅₎-1=2Δα-2Δθ ₀+Δδ。(28)

The ternary linear function group of finding the solution (26), (27) and (28) formula composition can obtain Δ θ ₀, Δ α and Δ δ.

Stokes' parameter is that the horizontal direction linearly polarized light of (1,1,0,0) is incident to device for testing polarization, establishes apparatus error in polarization detection device to be: the phase-delay quantity error delta δ of quarter wave plate, initial fast shaft angle degree error delta θ ₀, analyzer light transmission shaft angular error Δ α.According to the device error of process flow diagram recoverable device for testing polarization shown in Figure 2, concrete steps are as follows:

1, the original state of measuring for the first time is set: the system optical axis of setting up departments is the z axle of Cartesian coordinates, the forward of z axle is the light beam working direction, the plane vertical with the z axle is the xy plane, take the polarization direction of the horizontal direction linearly polarized light of incident as the x direction of principal axis, angle between the fast axle of x axle positive dirction and phase delay device is fast shaft angle degree θ, angle between x axle positive dirction and the analyzer light transmission shaft is the light transmission shaft angle [alpha], the phase-delay quantity of phase delay device is δ, take the design parameter of described phase delay device and analyzer as benchmark, adjust the initial fast shaft angle degree θ of described phase delay device ₀, described analyzer the light transmission shaft angle be 0 degree, and set the original state of this state for measuring for the first time;

2, measure for the first time: utilize the described phase delay device rotation of driver drives, described photodetector is surveyed light signal and output electrical signals, described electric signal obtains normalization Stokes' parameter (1, the S of incident beam after described signal processing system data are processed ₁₁, S ₁₂, S ₁₃), with known incident beam Stokes' parameter (S ₀₀, S ₀₁, S ₀₂, S ₀₃)=(1,1,0,0) compare, obtain the S of normalization Stokes' parameter ₁₁And S ₁₂Measuring error is for the first time

ΔS ₁₁=S ₁₁-S ₀₁=S ₁₁-1，ΔS ₁₂=S ₁₂-S ₀₂=S ₁₂-0=S ₁₂；

3, the original state of measuring for the second time is set: the original state light transmission shaft angle identical, described analyzer of the fast shaft angle degree of adjusting described phase delay device when measuring for the first time is 45 degree, and sets this state and be the original state of measurement for the second time;

4, measure for the second time: the described phase delay device rotation of described driver drives, described photodetector is surveyed light signal and output electrical signals, described electric signal carries out data through described signal processing system to described electric signal to be processed, obtain normalization Stokes' parameter (1, the S of incident beam ₂₁, S ₂₂, S ₂₃), compare with known incident beam Stokes' parameter (1,1,0,0), obtain normalization Stokes' parameter S ₂₁The measuring error second time be:

ΔS ₂₁=S ₂₁-S ₀₁=S ₂₁-1；

5, acquisition device error: the phase-delay quantity error delta δ of phase delay device, fast shaft angle degree error delta θ in the device for testing polarization ₀And the first time of the light transmission shaft angular error Δ α of analyzer and normalization Stokes' parameter, the second time concern below the existence between the measuring error: 2 Δs δ=Δ S ₁₁=S ₁₁-1,2 Δ α-4 Δ θ ₀=Δ S ₁₂=S ₁₂, 2 Δ α-2 Δ θ ₀+ Δ δ=Δ S ₂₁=S ₂₁-1, can be in the hope of Δ δ, Δ θ ₀With Δ α;

6, device error correction: when using described device for testing polarization to carry out Polarization Detection, for initial parameter δ, θ ₀With the value of α, utilize respectively Δ δ+δ, Δ θ ₀+ θ ₀Replace with the value of Δ α+α, namely realize the correction of the light transmission shaft angular error of the phase-delay quantity error of phase delay device, fast axle initial angle error and analyzer.

Figure 3 shows that the schematic diagram of illumination iris polarization parameter pick-up unit in the projection aligner that technology formerly 1 proposes.

The light beam of transform lens group 20 outgoing in the described device for testing polarization is parallel beam, and is the lens combination of polarization irrelevant or low-birefringence.

The bearing calibration of device for testing polarization device error of the present invention is applicable to this polarization parameter pick-up unit.Determine error delta θ ₀, behind Δ α, the Δ δ, the light transmission shaft angle by adjusting the initial fast shaft angle degree of phase delay device and analyzer or in computation process to initiation parameter θ ₀, α, δ revise, and realizes the device error correction of device for testing polarization, thereby realize the high-acruracy survey of incident beam polarization state.

Claims (3)

1. the bearing calibration of a device for testing polarization device error, the formation of described device for testing polarization comprises the phase delay device that sets gradually along the apparatus system optical axis, analyzer and photodetector, the output of this photodetector connects signal processing system, but described phase delay device is the rotation of winding apparatus systematic optical axis under the driving of driver, incident beam is parallel to systematic optical axis and is incident to described phase delay device and analyzer, and by described photodetector detection, the electric signal of this photodetector output is sent into described signal processing system and is carried out the data processing, it is characterized in that:

When utilizing described device for testing polarization to carry out Polarization Detection, the light transmission shaft angle of the phase-delay quantity of phase delay device, fast axle initial angle and analyzer is known, as initial parameter;

Described incident beam is the horizontal direction linearly polarized light, and its Stokes' parameter is (S ₀₀, S ₀₁, S ₀₂, S ₀₃)=(1,1,0,0);

Original state when measuring for the first time is that the light transmission shaft angle of described analyzer is 0 degree, carries out measuring for the first time the measuring error first time of normalization Stokes' parameter;

Original state when measuring for the second time is that the light transmission shaft angle of described analyzer is 45 degree, carries out measuring for the second time the measuring error second time of normalization Stokes' parameter;

Described signal processing system is processed the normalization Stokes' parameter measuring error that obtains for twice, obtain afterwards as calculated the light transmission shaft angular error of the phase-delay quantity error of phase delay device, fast shaft angle degree error and analyzer, and then the device error of recoverable device for testing polarization.

2. the bearing calibration of device for testing polarization device error according to claim 1 is characterized in that concrete aligning step is as follows:

1. the original state of measuring for the first time is set: the system optical axis of setting up departments is the z axle of Cartesian coordinates, the forward of z axle is the light beam working direction, the plane vertical with the z axle is the xy plane, take the polarization direction of the horizontal direction linearly polarized light of incident as the x direction of principal axis, angle between the fast axle of x axle positive dirction and phase delay device is fast shaft angle degree θ, angle between x axle positive dirction and the analyzer light transmission shaft is the light transmission shaft angle [alpha], and the phase-delay quantity of phase delay device is δ.Take described phase delay device and analyzer manufacture and design parameter as benchmark, adjust the initial fast shaft angle degree θ of described phase delay device ₀, described analyzer the light transmission shaft angle be 0 degree, and set the original state of this state for measuring for the first time;

2. measure for the first time: utilize the described phase delay device rotation of driver drives, described photodetector is surveyed light signal and output electrical signals, described electric signal obtains normalization Stokes' parameter (1, the S of incident beam after described signal processing system data are processed ₁₁, S ₁₂, S ₁₃), with known incident beam Stokes' parameter (S ₀₀, S ₀₁, S ₀₂, S ₀₃)=(1,1,0,0) compare, obtain the S of normalization Stokes' parameter ₁₁And S ₁₂Measuring error is for the first time:

ΔS ₁₁=S ₁₁-S ₀₁=S ₁₁-1，ΔS ₁₂=S ₁₂-S ₀₂=S ₁₂-0=S ₁₂；

3. the original state of measuring for the second time is set: the original state light transmission shaft angle identical, described analyzer of the fast shaft angle degree of adjusting described phase delay device when measuring for the first time is 45 degree, and sets this state and be the original state of measurement for the second time;

4. measure for the second time: the described phase delay device rotation of described driver drives, described photodetector is surveyed light signal and output electrical signals, described electric signal carries out data through described signal processing system to described electric signal to be processed, obtain normalization Stokes' parameter (1, the S of incident beam ₂₁, S ₂₂, S ₂₃), compare with known incident beam Stokes' parameter (1,1,0,0), obtain normalization Stokes' parameter S ₂₁The measuring error second time be:

ΔS ₂₁=S ₂₁-S ₀₁=S ₂₁-1；

5. acquisition device error: the phase-delay quantity error delta δ of phase delay device, fast shaft angle degree error delta θ in the device for testing polarization ₀And the first time of the light transmission shaft angular error Δ α of analyzer and normalization Stokes' parameter, the second time concern below the existence between the measuring error:

2 Δ δ Δ S ₁₁=S ₁₁-1,2 Δ α-4 Δ θ ₀=Δ S ₁₂=S ₁₂, 2 Δ α-2 Δ θ ₀+ Δ δ=Δ S ₂₁=S ₂₁-1, try to achieve Δ δ, Δ θ ₀With Δ α;

6. device error correction: when using described device for testing polarization to carry out Polarization Detection, for initial parameter δ, θ ₀With the value of α, utilize respectively Δ δ+δ, Δ θ ₀+ θ ₀Replace with the value of Δ α+α, namely realize the correction of the light transmission shaft angular error of the phase-delay quantity error of phase delay device, fast axle initial angle error and analyzer.

3. the bearing calibration of device for testing polarization device error according to claim 1, it is characterized in that the described phase delay device system for winding of described driver drives optical axis at the uniform velocity rotates, perhaps by driving the position of at least four different angles between fast axle that the phase delay device rotation can arrange phase delay device and the described analyzer light transmission shaft.

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