CN103954435A - Device and method for detecting phase delay and polarization dependent losses - Google Patents

Abstract

The invention relates to a device and method for detecting phase delay and polarization dependent losses. The device comprises a first phase delayer (10), a second phase delayer (11) and a feedback control system (7) provided with a calculation module. The calculation module is used for calculating the phase delay angle delta 1 and the polarization dependent loss PDL 1 of the first phase delayer (10) and the phase delay angle delta 2 and the polarization dependent loss PDL 2 of the second phase delayer (11), the relational expression is shown in the specification, and I(kpi, kpi), I(kpi+pi/4, kpi+pi/4), I(kpi+pi/2, kpi+pi/2), I(kpi, kpi+pi/2), I(kpi+pi/4, kpi+3*pi/4) and I(kpi+pi/2, kpi+pi) are the photoelectric current data measured by a photoelectric detector (6) at the same to-be-measured wavelength and different k values, or are the mean value of all of the photoelectric current data measured by the photoelectric detector (6) at the same to-be-measured wavelength and different k values. By means of the device and method, the fast axis positions, phase delay characters and the PDL characters of two unknown broadband phase delayers can be measured at the same time.

Description

Device and the detection method thereof of a kind of detected phase delay and Polarization Dependent Loss

Technical field

The invention belongs to polarization optics detection field, particularly a kind of method and device of the phase-delay characteristic and the Polarization Dependent Loss characteristic that detect two phase delay devices simultaneously.

Background technology

Phase delay device (or phase compensator) is widely used basic optical element in Experiments of Optics and optical instrument, and it is to utilize the birefringence effect of material to be made.In the time that linearly polarized light passes through this device perpendicular to phase delay device surface, in incident light, to be parallel to the speed that the component (e light) of phase delay device optical axis propagates in phase delay device with the component (o light) perpendicular to phase delay device optical axis different for electric vector, conventionally there is certain phase differential thereby see through between the e light of phase delay device and o light, make transmitted light there is multiple possible polarization characteristic.In principle, say, any material with birefringence effect can be used for making phase delay device, crystalline phase delayer, the liquid crystal phase delay device made by birefringece crystals such as quartz, kalzit, magnesium fluoride or micas that for example generally adopt, and magnetic liquid under external magnetic field, W sheet etc.But above-mentioned all material, except having birefringence effect, also has dichroism, this can directly cause the Polarization Dependent Loss (PDL, Polarization Dependent Loss) of device; And the phase-delay characteristic of phase delay device and dichroism (being PDL characteristic) be all functions of wavelength, within the scope of some common wavelengths, the PDL characteristic of phase delay device can produce a very large impact device performance.For example, in rotation double compensation device formula wide spectrum ellipsometer (PCSCA type ellipsometer), two whirl compensator C ₁, C ₂phase-delay characteristic and the accurate measurement of PDL characteristic be the prerequisite that realizes high-acruracy survey, any remaining polarization all will have influence on the precision of polarimetry.If consider whirl compensator C ₁, C ₂polarization Dependent Loss characteristic, the operation algorithm of PCSCA type ellipsometer must be made necessary correction.Therefore, the phase-delay characteristic of two whirl compensators and PDL characteristic all have material impact to overall performance.

The method of measurement polarizer phase delay or PDL has a variety of, but there is no any phase-delay quantity and PDL that can simultaneously measure two polarizers, more can not measure phase delay spectral characteristic and the PDL spectral characteristic of two polarizers simultaneously.

Summary of the invention

Object of the present invention is exactly in order to address the above problem, method and the device of the phase delay and Polarization Dependent Loss (PDL) characteristic that detect two phase delay devices are provided simultaneously, it belongs to non-cpntact measurement, simultaneously phase delay and the PDL characteristic of two phase delay devices of fast detecting; Easy to use efficient, can be used for the direct calibration of phase delay and the PDL characteristic of simultaneously carrying out two unknown phase delayers in actual production and research work, and measurement result is not subject to the impact of light source and detector spectrum characteristic.

To achieve these goals, the present invention adopts following technical scheme:

The device of a kind of detected phase delay and Polarization Dependent Loss, comprise natural light light source, feedback control system, the parallel natural light of natural light light source outgoing is successively by transmission axle is placed altogether the polarizer, the first rotating disk, the second rotating disk, analyzer, photodetector, the first rotating disk is connected with the first motor, and the second rotating disk is connected with the second motor; The same photodetector of feedback control system, the first motor, the second motor are connected and realize the rotation status of collection analysis photocurrent data FEEDBACK CONTROL the first motor and the second motor; Described the first rotating disk and the second rotating disk are hollow structure, in described the first rotating disk hollow structure, be provided with the locating device of fixing the first phase delay device, in described the second rotating disk hollow structure, be provided with the locating device of fixing the second phase delay device, described feedback control system is provided with computing module, is provided with computing module and calculates the first phase delay device (10) and the second phase delay device (11) phase delay angle δ ₁, δ ₂and polarized dependent loss PDL ₁, PDL ₂,

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{I(\mathrm{k\π},\mathrm{k\π})}$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{I(\mathrm{k\π},\mathrm{k\π})}$

Wherein, k is nonnegative integer (k=0,1,2,), photocurrent data I (k π, k π), I (k π+π/4, k π+π/4), I (k π+pi/2, k π+pi/2), I (k π, k π+pi/2), I (k π+π/4, π/4, k π+3) and I (k π+pi/2, k π+π) be the photocurrent data that photodetector is measured under same wavelength to be measured place, different value of K, or the mean value of photodetector all photocurrent data under same wavelength to be measured place, different value of K.

Described photodetector is photodiode or photomultiplier or CCD linear array or area array sensor, and its operating wavelength range covers the operating wavelength range of the first phase delay device and the second phase delay device.

The described polarizer and analyzer adopt dichroic polarizer or birefringent polarizer, and its operating wavelength range covers the operating wavelength range of the first phase delay device and the second phase delay device.

Described natural light light source is broadband lamp or the wavelength adjustable type lamp that output characteristics is stable, and its operating wavelength range covers the operating wavelength range of the first phase delay device and the second phase delay device.

In the light emitting source output light path of described natural light light source, be provided with expand-collimation lens set.

Apply the method that described device carries out detected phase delay and Polarization Dependent Loss, comprise the steps: step 1: regulate analyzer parallel with the polarization direction of the polarizer; Step 2: the polarization direction that regulates the first phase delay device, the parallel polarizer of the second phase delay device; Step 3: in the same way, synchronized rotation the first rotating disk and the second rotating disk, feedback control system is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π), I (k π+π/4, k π+π/4), I (k π+pi/2, k π+pi/2) and I (π/4, k π+3, π/4, k π+3), wherein k is nonnegative integer, at counting initial time definition k=0, after this first rotating disk and the every rotation half cycle of the second rotating disk k value increase by 1; Calculate respectively the photocurrent root-mean-square valve at each wavelength place $\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π},\mathrm{i\π})\right]}^2}{k}},\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}\{{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{4},\mathrm{i\π}+\frac{\mathrm{\π}}{4})\right]}^2+{\left[I(\mathrm{i\π}+\frac{3\mathrm{\π}}{4},\mathrm{i\π}+\frac{3\mathrm{\π}}{4})\right]}^2\}}{2k}}$ With $\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{2},\mathrm{i\π}+\frac{\mathrm{\π}}{2})\right]}^2}{k}};$ Regulate the quick shaft direction of the second phase delay device, make it mutually vertical with the quick shaft direction of the first phase delay device; Step 4: the zero clearing of k value is restarted to counting, method of counting is identical with step 3, synchronized rotation the first rotating disk and the second rotating disk in the same way,, feedback control system is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π+pi/2), I (k π+π/4, π/4, k π+3), I (k π+pi/2, k π+π) and I (π/4, k π+3, π/4, k π+5), calculate respectively root-mean-square valve $\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π},\mathrm{i\π}+\frac{\mathrm{\π}}{2})\right]}^2}{k}},$ $\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}\{{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{4},\mathrm{i\π}+\frac{3\mathrm{\π}}{4})\right]}^2+{\left[I(\mathrm{i\π}+\frac{3\mathrm{\π}}{4},\mathrm{i\π}+\frac{5\mathrm{\π}}{4})\right]}^2\}}{2k}}$ With $\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{2},\mathrm{i\π}+\mathrm{\π})\right]}^2}{k}};$ Step 5: the phase delay angle δ that is calculated the first phase delay device and the second phase delay device by the computing module of feedback control system ₁, δ ₂, and calculate polarized dependent loss PDL ₁and PDL ₂,

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-10\lg \frac{D_2}{D_1}=-5\lg \frac{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})}$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-10\lg \frac{L_2}{L_1}=-5\lg \frac{\stackrel{\‾}{I}\left(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π}\right)}{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})},$ Testing process finishes.

Between described step 1 and step 2, also comprise the steps: step 1-1: search the fast axis direction of the second phase delay device, carry out after mark, it is taken off from the second rotating disk; Step 1-2: search the fast axis direction of the first phase delay device, and carry out mark, then the second phase delay device is put back to the second rotating disk.

The specific implementation of searching phase delay device fast axis direction in described step 1-1, step 1-2 is: phase delay device is fixed on rotating disk, ensure and light path devices transmission axle placement altogether, rotary turnplate is until the photocurrent of photodetector output reaches maximal value.

Apply the method that described device carries out detected phase delay and Polarization Dependent Loss, it is characterized in that, comprise the steps: step 1: regulate analyzer parallel with the polarization direction of the polarizer; Step 2: the polarization direction that regulates the first phase delay device, the parallel polarizer of the second phase delay device; Step 3: in the same way, synchronized rotation the first rotating disk and the second rotating disk, feedback control system is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π), I (k π+π/4, k π+π/4) and I (k π+pi/2, k π+pi/2), wherein k is nonnegative integer; Regulate the quick shaft direction of the second phase delay device, make it mutually vertical with the quick shaft direction of the first phase delay device; Step 4: the zero clearing of k value is restarted to counting, synchronized rotation the first rotating disk and the second rotating disk in the same way,, feedback control system is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π+pi/2), I (k π+π/4, π/4, k π+3) and I (k π+pi/2, k π+π); Step 5: by feedback control system and computing module

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{I(\mathrm{k\π},\mathrm{k\π})}$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{I(\mathrm{k\π},\mathrm{k\π})}$ Calculate the first phase delay device and the second phase delay device phase delay angle δ at all k values place _1k, δ _2k, and calculate polarized dependent loss PDL _1kand PDL _2k; To the δ at all k values place _1k, δ _2k, PDL _1kand PDL _2kask quadratic sum, get root-mean-square valve, testing process finishes.

Between described step 1 and step 2, also comprise the steps: step 1-1: search the fast axis direction of the second phase delay device, carry out after mark, it is taken off from the second rotating disk; Step 1-2: search the fast axis direction of the first phase delay device, and carry out mark, then the second phase delay device is put back to the second rotating disk.

Beneficial effect of the present invention:

1) measuring method of the present invention belongs to non-cpntact measurement, can measure fast shaft position, phase-delay characteristic and the PDL characteristic of two unknown broadband phase delay devices simultaneously, easy to use efficient, can be used for the direct calibration of the phase-delay quantity that simultaneously carries out two unknown zero level phase delay devices in actual production and research work.

2) in multi-wavelength light electric explorer, the characteristic of each probe unit and incident intensity the unknown, do not need complicated Fourier analysis and solve to demarcate rapidly and accurately the phase delay spectrum of two zero level phase delay devices to be measured at wave band to be investigated simultaneously.

3), with respect to other measuring method, the measured zero level phase delay device phase delay of the present invention is wider, can be both 1/4 phase delay device, can not be also 1/4 phase delay device.

Brief description of the drawings

Fig. 1 is phase delay device phase-delay characteristic involved in the present invention and the universal architecture schematic diagram of Polarization Dependent Loss characteristic measuring device;

Fig. 2 is phase delay device phase-delay characteristic involved in the present invention and the detection method process flow diagram of Polarization Dependent Loss characteristic measuring device;

Wherein:

1, lamp; 2, the polarizer;

3, the first rotating disk; 4, the second rotating disk;

5, analyzer; 6, photodetector;

7, feedback control system; 8, the first motor;

9, the second motor; 10, the first phase delay device;

11, the second phase delay device; 20: heat-conducting silicone grease;

Embodiment

Innovative point of the present invention has been to provide method and the device of the phase delay and Polarization Dependent Loss (PDL) characteristic that simultaneously detect two phase delay devices.Below in conjunction with embodiment, the present invention is described in detail.

The structure of the device for fast detecting of the phase-delay characteristic of phase delay device of the present invention and Polarization Dependent Loss characteristic is as shown in Figure 1: comprise natural light light source 1 and feedback control system 7, the parallel natural light of natural light light source 1 outgoing is successively by transmission axle is placed altogether the polarizer 2, the first rotating disk 3, the second rotating disk 4, analyzer 5, photodetector 6, the first rotating disk 3 is connected with the first motor 8, and the second rotating disk 4 is connected with the second motor 9; Feedback control system 7 is connected and realizes the rotation status of collection analysis photocurrent data FEEDBACK CONTROL the first motor 8 and the second motor 9 with photodetector 6, the first motor 8, the second motor 9; Described the first rotating disk 3 and the second rotating disk 4 are hollow structure, in described the first rotating disk 3 hollow structures, are provided with the locating device of fixing the first phase delay device 10, in described the second rotating disk 4 hollow structures, are provided with the locating device of fixing the second phase delay device 11.In the present embodiment, adopt the periphery of hollow structure to have multiple pilot holes, by this pilot hole, the first phase delay device 10 and the second phase delay device 11 are separately fixed to the hollow structure part of the first rotating disk 3 and the second rotating disk 4; And controlled respectively the rotation status of the first rotating disk 3 and the second rotating disk 4 by the first motor 8 and the second motor 9.

Described feedback control system 7 is provided with computing module, and computing module is provided with and calculates the first phase delay device 10 and the second phase delay device 11 phase delay angle δ ₁, δ ₂and polarized dependent loss PDL ₁, PDL ₂relational expression:

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{I(\mathrm{k\π},\mathrm{k\π})}$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{I(\mathrm{k\π},\mathrm{k\π})}$

Wherein, k is nonnegative integer (k=0,1,2,), photocurrent data I (k π, k π), I (k π+π/4, k π+π/4), I (k π+pi/2, k π+pi/2), I (k π, k π+pi/2), I (k π+π/4, π/4, k π+3) and I (k π+pi/2, k π+π) be the photocurrent data that photodetector 6 is measured under same wavelength to be measured place, different value of K, or the mean value of photodetector 6 all photocurrent data under same wavelength to be measured place, different value of K.

Described natural light light source 1 is broadband lamp or the wavelength adjustable type lamp that output characteristics is stable, and its operating wavelength range can cover the operating wavelength range of the first phase delay device 10 and the second phase delay device 11.In concrete application, according to the spot size of this light source and beam quality, in the light emitting source output light path of natural light light source 1, be provided with expand-collimation lens set.

The described polarizer 2 and analyzer 5 can adopt the one in dichroic polarizer or birefringent polarizer, and its operating wavelength range can cover the operating wavelength range of the first phase delay device 10 and the second phase delay device 11.

The application requirements of described the first rotating disk 3 and the second rotating disk 4 is control requirements that the rotation precision of two rotating disks all should meet feedback control system 7, and common commercial product all can meet this application requirements.

Described photodetector 6 is photodiode, photomultiplier or CCD (Charge-coupled Device) linear array or area array sensor, carry out data processing for the photo-signal detecting is reached to feedback control system 7 through data collecting card, its operating wavelength range can cover the operating wavelength range of the first phase delay device 10 and the second phase delay device 11.

After the photocurrent data that described feedback control system 7 collection analysis photodetectors 6 detect, send the rotation status of pulse signal through motor driver adjustment motor according to certain feedback control algorithm.

Described the first motor 8 and the second motor 9 and motor driver thereof are selected servomotor, p-m step motor or reaction stepping motor, and the motor driver matching with the motor of above every type.Because the first rotating disk 3 in the present invention is connected with the first motor 8, the second rotating disk 4 is connected with the second motor 9, and controlled respectively the rotation status of the first rotating disk 3 and the second rotating disk 4 by the first motor 8 and the second motor 9, in practical application, also can select integrated to single motor and the single rotating disk electric rotary commodity that are produced on together to be come respectively as the first rotating disk 3 being connected and the first motor 8, and the second rotating disk 4 being connected and the second motor 9.

All for single or compound phase delay device of the making such as the magnetic liquid by under crystalline material, polymeric material, liquid crystal, external magnetic field etc., all possess the optical device of phase delay function for described the first phase delay device 10 and the second phase delay device 11.

As shown in Figure 2, its concrete steps are as follows for the process of the phase delay angle of a kind of phase delay device of the present invention and the pick-up unit practical function of Polarization Dependent Loss characteristic:

Step 1: regulate analyzer 5 parallel with the polarization direction of the polarizer 2;

Step 2: the first phase delay device 10, the second phase delay device 11 are individually fixed on the locating device of the first rotating disk 3, the second rotating disk 4, regulate the quick shaft direction of the first phase delay device 10 and the second phase delay device 11 to be parallel to each other, this quick shaft direction is parallel to each other with the polarizer 2 and the polarization direction of analyzer 5 simultaneously;

Step 3: with angular velocity w in the same way, synchronized rotation the first rotating disk 3 and the second rotating disk 4, now rotation angle C ₁=C ₂=wt, feedback control system 7 is according to the photocurrent data I (C that the concrete testing requirement of the first phase delay device 10 and the second phase delay device 11 is captured in to corresponding detection wavelength place ₁, C ₂), especially I (k π, k π), I (k π+π/4, k π+π/4) and I (k π+pi/2, k π+pi/2), wherein k is that nonnegative integer is (at the counting initial time of t=0, definition k=0, every rotation half cycle k value increases by 1); It is to detect phase delay angle and the Polarization Dependent Loss characteristic of two phase delay devices in a certain certain wave strong point that testing requirement is actually, still detect phase delay angle characteristic and the Polarization Dependent Loss characteristic of two phase delay devices in a certain wavelength coverage, in the time being the latter's testing requirement, need to be captured in by detector array the photocurrent data at all wavelengths place in required wavelength coverage, finally obtain phase delay angle spectral characteristic and the Polarization Dependent Loss spectral characteristic of two phase delay devices in this wavelength coverage.Rotation angle C ₁, C ₂after changing k π, stop sampling, now the neglecting greatly concrete detection case and can set voluntarily of k value, then regulate the quick shaft direction of the second phase delay device 11, make it mutually vertical with the quick shaft direction of the first phase delay device 10, keep the quick shaft direction of the first phase delay device 10 and the polarization direction of the polarizer 2 and analyzer 5 to be parallel to each other, the rotation angle of this latter two phase delay device meets relational expression C simultaneously ₂=C ₁+ pi/2;

Step 4: the zero clearing of k value is restarted to counting, simultaneously with same angular velocity in the same way, synchronized rotation the first rotating disk 3 and the second rotating disk 4, feedback control system 7 is captured in the photocurrent data I (C at corresponding detection wavelength place ₁, C ₂), especially I (k π, k π+pi/2), I (k π+π/4, π/4, k π+3) and I (k π+pi/2, k π+π); The phase delay angle δ about the first phase delay device 10 and the second phase delay device 11 arranging in computing module by feedback control system 7 ₁, δ ₂, and polarized dependent loss PDL ₁and PDL ₂computing formula, calculate and export the characteristic at each detection wavelength place the first phase delay device 10 and the second phase delay device 11.When calculating the first phase delay device 10 and the second phase delay device 11 phase delay angle δ at all k values place _1k, δ _2k, and calculate polarized dependent loss PDL _1kand PDL _2kafter, to the δ at all k values place _1k, δ _2k, PDL _1kand PDL _2kask quadratic sum and get its root-mean-square valve, testing process finishes.

Calculating the first phase place A delayer 10 arranging in the computing module of feedback control system 7 and the second phase delay device 11 phase delay angle δ ₁, δ ₂, and calculate polarized dependent loss PDL ₁and PDL ₂formula be specially:

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{I(\mathrm{k\π},\mathrm{k\π})}$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{I(\mathrm{k\π},\mathrm{k\π})}$

The phase delay angle of a kind of phase delay device as above and the detection method of Polarization Dependent Loss characteristic, also comprise the steps: between described step 1 and step 2

Step 1-1: search the fast axis direction of the second phase delay device 11, carry out after mark, it is taken off from the second rotating disk 4;

Step 1-2: search the fast axis direction of the first phase delay device 10, and carry out mark, then the second phase delay device 11 is put back to the second rotating disk 4.

The specific implementation of searching phase delay device fast axis direction in described step 1-1, step 1-2 is: phase delay device is fixed on rotating disk, ensure and light path devices transmission axle placement altogether, rotary turnplate is until the photocurrent of photodetector output reaches maximal value.

The phase delay angle of a kind of phase delay device as above and the detection method of Polarization Dependent Loss characteristic, the phase delay angle δ arranging in feedback control system 7 in described step 4 ₁, δ ₂, PDL ₁and PDL ₂each photocurrent data in computing formula, both can adopt photocurrent data I (k π, k π), I (k π+π/4 of each measurement, k π+π/4), I (k π+pi/2, k π+pi/2), I (k π, k π+pi/2), I (k π+π/4, π/4, k π+3) and I (k π+pi/2, k π+π), wherein integer k=0,1,2,, obtain respectively the δ under several different value of K _1k, δ _2k, PDL _1kand PDL _2kvalue, then the δ to all k values place respectively _1k, δ _2k, PDL _1kand PDL _2ksummation is averaged, and obtains final δ ₁, δ ₂, PDL ₁and PDL ₂data; Also other various measures that reduce error can be adopted, for example, the following root-mean-square valve of each wavelength place photocurrent can be in step 3, calculated respectively with and in step 4, calculate respectively root-mean-square valve with then the calculating δ, arranging in feedback control system 7 ₁, δ ₂, PDL ₁and PDL ₂formula in, adopt above-mentioned root-mean-square valve replace respectively corresponding I (C ₁, C ₂), obtain the δ at each wavelength to be measured place ₁, δ ₂, PDL ₁and PDL ₂data are also preserved output data, end operation.Its idiographic flow comprises the steps:

Step 1: regulate analyzer 5 parallel with the polarization direction of the polarizer 2;

Step 2: the polarization direction that regulates the first phase delay device 10, the parallel polarizer 2 of the second phase delay device 11;

Step 3: in the same way, synchronized rotation the first rotating disk 3 and the second rotating disk 4, feedback control system 7 is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π), I (k π+π/4, k π+π/4), I (k π+pi/2, k π+pi/2) and I (π/4, k π+3, π/4, k π+3), wherein k is nonnegative integer, at counting initial time definition k=0, after this first rotating disk 3 and the every rotation half cycle of the second rotating disk 4 k value increase by 1; Calculate respectively the root-mean-square valve of each wavelength place photocurrent

$\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π},\mathrm{i\π})\right]}^2}{k}}$

$\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}\{{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{4},\mathrm{i\π}+\frac{\mathrm{\π}}{4})\right]}^2+{\left[I(\mathrm{i\π}+\frac{3\mathrm{\π}}{4},\mathrm{i\π}+\frac{3\mathrm{\π}}{4})\right]}^2\}}{2k}}$

$\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{2},\mathrm{i\π}+\frac{\mathrm{\π}}{2})\right]}^2}{k}};$ Regulate the quick shaft direction of the second phase delay device 11, make it mutually vertical with the quick shaft direction of the first phase delay device 10;

Step 4: the zero clearing of k value is restarted to counting, method of counting is identical with step 3, synchronized rotation the first rotating disk 3 and the second rotating disk 4 in the same way,, feedback control system 7 is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π+pi/2), I (k π+π/4, π/4, k π+3), I (k π+pi/2, k π+π) and I (π/4, k π+3, π/4, k π+5), calculate respectively root-mean-square valve

$\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π},\mathrm{i\π}+\frac{\mathrm{\π}}{2})\right]}^2}{k}},$

$\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}\{{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{4},\mathrm{i\π}+\frac{3\mathrm{\π}}{4})\right]}^2+{\left[I(\mathrm{i\π}+\frac{3\mathrm{\π}}{4},\mathrm{i\π}+\frac{5\mathrm{\π}}{4})\right]}^2\}}{2k}}$

$\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{2},\mathrm{i\π}+\mathrm{\π})\right]}^2}{k}};$

Step 5: by the formula arranging in feedback control system 7 computing modules

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-10\lg \frac{D_2}{D_1}=-5\lg \frac{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})}$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-10\lg \frac{L_2}{L_1}=-5\lg \frac{\stackrel{\‾}{I}\left(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π}\right)}{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})}$

Calculate the phase delay angle δ of the first phase delay device 10 and the second phase delay device 11 ₁, δ ₂, and calculate polarized dependent loss PDL ₁and PDL ₂, testing process finishes.

Introduce the theoretical foundation of every formula in above-mentioned steps three and step 4 below.According to the correlation theory of polarization optics, the Stokes of the natural light that the natural light light source 1 in Fig. 1 shown device sends represents Sin, and the Stokes of the light signal that detects of photodetector 6 represents to meet between Sout following relation:

S _out＝M _A·M _C2(C ₂,δ ₂,D ₁,D ₂)·M _C1(C ₁,δ ₁,L ₁,L ₂)·M _P·S _in (1)

Wherein, M _p, M _a, MC ₁, MC ₂be respectively the Muller matrix of the polarizer 2, analyzer 5, the first phase delay device 10 and the second phase delay device 11; C ₁, δ ₁, L ₁, L ₂be respectively the fast axle of the first phase delay device 10 with respect to the phase-delay quantity of the angle of polarizer polarization direction, the first phase delay device 10 and the dichroism absorption coefficient of the fast axle of the first phase delay device 10 and slow axis; In like manner, C ₂, δ ₂, D ₁, D ₂be respectively the fast axle of the second phase delay device 11 with respect to the phase-delay quantity of the angle of polarizer polarization direction, the second phase delay device 11 and the dichroism absorption coefficient of the fast axle of the second phase delay device 11 and slow axis.The Stokes of the natural light that natural light light source 1 sends is expressed as:

$S_{\mathrm{in}}=\left(\begin{array}{c}S0\\ S1\\ S2\\ S3\end{array}\right)=\left(\begin{array}{c}1\\ 0\\ 0\\ 0\end{array}\right)$

The Muller matrix of the polarizer 2 and analyzer 5: $M_P=M_A=\frac{1}{2}\·\left(\begin{array}{cccc}1& 1& 0& 0\\ 1& 1& 0& 0\\ 0& 0& 0& 0\\ 0& 0& 0& 0\end{array}\right)$

The Muller matrix of the first phase delay device 4:

$M_{C1}(C_1,{\mathrm{\δ}}_1,L_1,L_2)=\left(\begin{array}{cccc}{L}_1^2+L_2^2& (L_1^2-L_2^2)\·\cos 2C_1& (L_1^2-L_2^2)\·\sin 2C_1& 0\\ (L_1^2-L_2^2)\·\cos 2C_1& (L_1^2+L_2^2)\·{\cos }^{2}2C_1+2L_1{L}_2\cos {\mathrm{\δ}}_1\·{\sin }^{2}2C_1& \frac{1}{2}\·\sin 4C_1\·(L_1^2+L_2^2-2L_1{L}_2\cos {\mathrm{\δ}}_1)& -2L_1{L}_2\sin {\mathrm{\δ}}_1\·\sin 2C_1\\ (L_1^2-L_2^2)\·\sin 2C_1& \frac{1}{2}\·\sin 4C_1\·(L_1^2+L_2^2-2L_1{L}_2\cos {\mathrm{\δ}}_1)& (L_1^2+L_2^2)\·{\sin }^{2}2C_1+2L_1{L}_2\cos {\mathrm{\δ}}_1\·{\cos }^{2}2C_1& 2L_1{L}_2\sin {\mathrm{\δ}}_1\·\cos 2C_1\\ 0& 2L_1{L}_2\sin {\mathrm{\δ}}_1\·{\sin 2C}_1& -{2L}_1{L}_2\sin {\mathrm{\δ}}_1\·\cos 2C_1& 2L_1{L}_2\cos {\mathrm{\δ}}_1\end{array}\right)$

The Muller matrix of the second phase delay device 5:

$M_{C2}(C_2,{\mathrm{\δ}}_2,D_1,D_2)=\left(\begin{array}{cccc}{D}_1^2+D_2^2& (D_1^2-D_2^2)\·\cos 2C_2& (D_1^2-D_2^2)\·\sin 2C_2& 0\\ (D_1^2-D_2^2)\·\cos 2C_2& (D_1^2+D_2^2)\·{\cos }^{2}2C_2+2D_1{D}_2\cos {\mathrm{\δ}}_2\·{\sin }^{2}2C_2& \frac{1}{2}\·\sin 4C_2\·(D_1^2+D_2^2-2D_1{D}_2\cos {\mathrm{\δ}}_2)& -2D_1{D}_2\sin {\mathrm{\δ}}_2\·\sin 2C_2\\ (D_1^2-D_2^2)\·\sin 2C_2& \frac{1}{2}\·\sin 4C_2\·(D_1^2+D_2^2-2D_1{D}_2\cos {\mathrm{\δ}}_2)& (D_1^2+D_2^2)\·{\sin }^{2}2C_2+2D_1{D}_2\cos {\mathrm{\δ}}_2\·{\cos }^{2}2C_2& 2{D_{1}D}_2\sin {\mathrm{\δ}}_2\·\cos 2C_2\\ 0& 2D_1{D}_2\sin {\mathrm{\δ}}_2\·{\sin 2C}_2& -{2D}_1{D}_2\sin {\mathrm{\δ}}_2\·\cos 2C_2& 2D_1{D}_2\cos {\mathrm{\δ}}_2\end{array}\right)$

The expression of the S0 component of output optical signal Sout is:

$\begin{array}{c}{S}_0(D_1,D_2,L_1,L_2,{\mathrm{\δ}}_1,{\mathrm{\δ}}_2,C_1,C_2)=[D_1^2+D_2^2+(D_1^2-D_2^2)\·\cos 2C_2]\·[L_1^2+L_2^2+(L_1^2-L_2^2)\·\cos 2C_1]+\\ +[(D_1^2-D_2^2)\·\cos 2C_2+(D_1^2+D_2^2)\·{\cos }^{2}2C_2+2D_1{D}_2\cos {\mathrm{\δ}}_2\·{\sin }^{2}2C_2]\·[(L_1^2-L_2^2)\·\cos {2C}_1+(L_1^2+L_2^2)\·{\cos }^{2}2C_1+{2L}_1{L}_2\cos {\mathrm{\δ}}_1\·{\sin }^{2}2C_1]+\\ +[(D_1^2-D_2^2)\·\sin {2C}_2+\frac{1}{2}\·(D_1^2+D_2^2-2D_1{D}_2\cos {\mathrm{\δ}}_2)\·\sin 4C_2]\·[(L_1^2-L_2^2)\·\sin {2C}_1+\frac{1}{2}\·(L_1^2+L_2^2-2L_1{L}_2\cos {\mathrm{\δ}}_1)\·\sin 4C_1]-\\ -4D_1{D}_2{L}_1{L}_2\sin {\mathrm{\δ}}_1{\sin \mathrm{\δ}}_2\sin 2C_1\sin {2C}_2\end{array}$

Due at any wavelength place, the output photoelectric stream of 6 corresponding probe units of photodetector is proportional to the light intensity of the output optical signal S0 of this wavelength place component,

I(C ₁,C ₂)＝η·S ₀(D ₁,D ₂,L ₁,L ₂,δ ₁,δ ₂,C ₁,C ₂) (2)

Wherein real number η is 1 the scale-up factor of being less than of considering that the impact of the factor such as detective quantum efficiency introduces, and result of calculation last in this value and the present invention has nothing to do.As shown from the above formula, output photoelectric stream is actually C ₁, C ₂, D ₁, D ₂, L ₁, L ₂, δ ₁, δ ₂function, for the convenience that follow-up formula (3.a～3.f) and (4.a～4.d) represent, be abbreviated as I (C herein ₁, C ₂).In the situation that system performance is stable, at any one definite wavelength place, photocurrent I (C ₁, C ₂) about independent variable C ₁and C ₂be to be all the function of π in the cycle, and have following relation to occur in several special angle:

$I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})=I(\mathrm{k\π}+\frac{3\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})=\mathrm{\η}\·[2D_1^2{L}_1^2+2D_2^2{L}_2^2+4D_1{D}_2{L}_1{L}_2\cos ({\mathrm{\δ}}_1+{\mathrm{\δ}}_2)]---(3.a)$

$I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})=I(\mathrm{k\π}+\frac{3\mathrm{\π}}{4},\mathrm{k\π}+\frac{5\mathrm{\π}}{4})=\mathrm{\η}\·[2D_2^2{L}_1^2+2D_1^2{L}_2^2+4D_1{D}_2{L}_1{L}_2\cos ({\mathrm{\δ}}_1-{\mathrm{\δ}}_2)]---(3.b)$

$I(\mathrm{k\π},\mathrm{k\π})=8{\mathrm{\ηD}}_1^2{L}_1^2---(3.c)$

$I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})=8{\mathrm{\ηD}}_2^2{L}_2^2---(3.d)$

$I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})=8{\mathrm{\ηD}}_2^2{L}_1^2---(3.e)$

$I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})=8{\mathrm{\ηD}}_1^2{L}_2^2---(3.f)$

Utilize above formula can obtain the phase-delay quantity of the first phase delay device 4 and the second phase delay device 5:

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]---(4.a)$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]---(4.b)$

The polarized dependent loss PDL of the first phase delay device 4 and the second phase delay device 5 ₁, PDL ₂and the pass between dichroism absorption coefficient is separately:

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-10\lg \frac{D_2}{D_1}=-5\lg \frac{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{I(\mathrm{k\π},\mathrm{k\π})}---(4.c)$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-10\lg \frac{L_2}{L_1}=-5\lg \frac{I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{I(\mathrm{k\π},\mathrm{k\π})}---(4.d)$

In formula (4.a-4.d), along with increase (integer k=0,1,2 of k value,), all can obtain many group photocurrent data I (k π, k π), I (k π+π/4, k π+π/4), I (k π+pi/2 at each wavelength to be measured place, k π+pi/2), I (k π, k π+pi/2), I (k π+π/4, π/4, k π+3) and I (k π+pi/2, k π+π); For eliminating the impact in the slight error source such as anglec of rotation deviation, photodetector noise of the first phase delay device 10 and the second phase delay device 11, can in specific implementation process, adopt the various measures that reduce error, both can in abovementioned steps three and step 4, adopt the photocurrent data under each k value, obtain respectively the δ under several different value of K _1k, δ _2k, PDL _1kand PDL _2kvalue, then the δ to all k values place respectively _1k, δ _2k, PDL _1kand PDL _2kask quadratic sum, and get its r.m.s., obtain final δ ₁, δ ₂, PDL ₁and PDL ₂data; Also other various measures that reduce error can be adopted, for example, the following root-mean-square valve of each wavelength place photocurrent can be in step 3, calculated respectively with and in step 4, calculate respectively root-mean-square valve with then the calculating δ, arranging in feedback control system 7 ₁, δ ₂, PDL ₁and PDL ₂formula in, adopt above-mentioned root-mean-square valve replace respectively corresponding I (C ₁, C ₂), as shown in formula (5.a-5.d), obtain the δ at each wavelength to be measured place ₁, δ ₂, PDL ₁and PDL ₂data are also preserved output data, end operation.

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]---(5.a)$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]---(5.b)$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-10\lg \frac{D_2}{D_1}=-5\lg \frac{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})}---(5.c)$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-10\lg \frac{L_2}{L_1}=-5\lg \frac{\stackrel{\‾}{I}\left(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π}\right)}{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})}---(5.d)$

Wherein, the expression formula of each root-mean-square valve is as follows:

$\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π},\mathrm{i\π})\right]}^2}{k}}$

$\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{2},\mathrm{i\π}+\frac{\mathrm{\π}}{2})\right]}^2}{k}}$

$\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}\{{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{4},\mathrm{i\π}+\frac{\mathrm{\π}}{4})\right]}^2+{\left[I(\mathrm{i\π}+\frac{3\mathrm{\π}}{4},\mathrm{i\π}+\frac{3\mathrm{\π}}{4})\right]}^2\}}{2k}}$

$\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π},\mathrm{i\π}+\frac{\mathrm{\π}}{2})\right]}^2}{k}}$

$\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{2},\mathrm{i\π}+\mathrm{\π})\right]}^2}{k}}$

$\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}\{{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{4},\mathrm{i\π}+\frac{3\mathrm{\π}}{4})\right]}^2+{\left[I(\mathrm{i\π}+\frac{3\mathrm{\π}}{4},\mathrm{i\π}+\frac{5\mathrm{\π}}{4})\right]}^2\}}{2k}}$

By reference to the accompanying drawings the specific embodiment of the present invention is described although above-mentioned; but not limiting the scope of the invention; one of ordinary skill in the art should be understood that; on the basis of technical scheme of the present invention, those skilled in the art do not need to pay various amendments that creative work can make or distortion still in protection scope of the present invention.

Claims (10)

1. a detected phase postpones and the device of Polarization Dependent Loss, it is characterized in that: comprise natural light light source (1), feedback control system (7), the parallel natural light of natural light light source (1) outgoing is successively by transmission axle is placed altogether the polarizer (2), the first rotating disk (3), the second rotating disk (4), analyzer (5), photodetector (6), the first rotating disk (3) is connected with the first motor (8), and the second rotating disk (4) is connected with the second motor (9); The same photodetector of feedback control system (7) (6), the first motor (8), the second motor (9) are connected and realize the rotation status of collection analysis photocurrent data FEEDBACK CONTROL the first motor (8) and the second motor (9); Described the first rotating disk (3) and the second rotating disk (4) are hollow structure, in described the first rotating disk (3) hollow structure, be provided with the locating device of fixing the first phase delay device (10), in described the second rotating disk (4) hollow structure, be provided with the locating device of fixing the second phase delay device (11), described feedback control system (7) is provided with computing module and calculates the first phase delay device (10) and the second phase delay device (11) phase delay angle δ ₁, δ ₂and polarized dependent loss PDL ₁, PDL ₂:

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{I(\mathrm{k\π},\mathrm{k\π})}$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{I(\mathrm{k\π},\mathrm{k\π})}$

Wherein, k is nonnegative integer (k=0,1,2,), photocurrent data I (k π, k π), I (k π+π/4, k π+π/4), I (k π+pi/2, k π+pi/2), I (k π, k π+pi/2), I (k π+π/4, π/4, k π+3) and I (k π+pi/2, k π+π) be the photocurrent data that photodetector (6) is measured under same wavelength to be measured place, different value of K, or the mean value of photodetector (6) all photocurrent data under same wavelength to be measured place, different value of K.

2. the device of a kind of detected phase delay according to claim 1 and Polarization Dependent Loss, it is characterized in that: described photodetector (6) is photodiode or photomultiplier or CCD linear array or area array sensor, and its operating wavelength range covers the operating wavelength range of the first phase delay device (10) and the second phase delay device (11).

3. the device of a kind of detected phase delay according to claim 1 and Polarization Dependent Loss, it is characterized in that: the described polarizer (2) and analyzer (5) adopt dichroic polarizer or birefringent polarizer, and its operating wavelength range covers the operating wavelength range of the first phase delay device (10) and the second phase delay device (11).

4. the device of a kind of detected phase delay according to claim 1 and Polarization Dependent Loss, it is characterized in that: described natural light light source (1) is stable broadband lamp or the wavelength adjustable type lamp of output characteristics, and its operating wavelength range covers the operating wavelength range of the first phase delay device (10) and the second phase delay device (11).

5. the device of a kind of detected phase delay according to claim 1 and Polarization Dependent Loss, is characterized in that: in the light emitting source output light path of described natural light light source (1), be provided with expand-collimation lens set.

6. application rights requires device described in 1 to carry out a method for detected phase delay and Polarization Dependent Loss, it is characterized in that, comprises the steps:

Step 1: regulate analyzer (5) parallel with the polarization direction of the polarizer (2);

Step 2: the polarization direction that regulates the first phase delay device (10), the parallel polarizer of the second phase delay device (11) (2);

Step 3: in the same way, synchronized rotation the first rotating disk (3) and the second rotating disk (4), feedback control system (7) is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π), I (k π+π/4, k π+π/4), I (k π+pi/2, k π+pi/2) and I (π/4, k π+3, π/4, k π+3), wherein k is nonnegative integer, at counting initial time definition k=0, after this first rotating disk (3) and the every rotation half cycle of the second rotating disk (4) k value increase by 1; Calculate respectively the photocurrent root-mean-square valve at each wavelength place $\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}\{{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{4},\mathrm{i\π}+\frac{\mathrm{\π}}{4})\right]}^2+{\left[I(\mathrm{i\π}+\frac{3\mathrm{\π}}{4},\mathrm{i\π}+\frac{3\mathrm{\π}}{4})\right]}^2\}}{2k}}$ With $\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{2},\mathrm{i\π}+\frac{\mathrm{\π}}{2})\right]}^2}{k}};$ Regulate the quick shaft direction of the second phase delay device (11), make it mutually vertical with the quick shaft direction of the first phase delay device (10);

Step 4: the zero clearing of k value is restarted to counting, method of counting is identical with step 3, synchronized rotation the first rotating disk (3) and the second rotating disk (4) in the same way,, feedback control system (7) is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π+pi/2), I (k π+π/4, π/4, k π+3), I (k π+pi/2, k π+π) and I (π/4, k π+3, π/4, k π+5), calculate respectively root-mean-square valve $\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}\{{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{4},\mathrm{i\π}+\frac{3\mathrm{\π}}{4})\right]}^2+{\left[I(\mathrm{i\π}+\frac{3\mathrm{\π}}{4},\mathrm{i\π}+\frac{5\mathrm{\π}}{4})\right]}^2\}}{2k}}$ With $\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})=\sqrt{\frac{\underset{i=0}{\overset{k}{\mathrm{\Σ}}}{\left[I(\mathrm{i\π}+\frac{\mathrm{\π}}{2},\mathrm{i\π}+\mathrm{\π})\right]}^2}{k}};$

Step 5: the phase delay angle δ that is calculated the first phase delay device (10) and the second phase delay device (11) by the computing module of feedback control system (7) ₁, δ ₂, and calculate polarized dependent loss PDL ₁and PDL ₂,

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·\stackrel{\‾}{I}(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-10\lg \frac{D_2}{D_1}=-5\lg \frac{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})}$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-10\lg \frac{L_2}{L_1}=-5\lg \frac{\stackrel{\‾}{I}\left(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π}\right)}{\stackrel{\‾}{I}(\mathrm{k\π},\mathrm{k\π})},$ Testing process finishes.

7. the detection method of a kind of phase delay and Polarization Dependent Loss according to claim 5, is characterized in that: between described step 1 and step 2, also comprise the steps:

Step 1-1: search the fast axis direction of the second phase delay device (11), carry out after mark, it is taken off from the second rotating disk (4);

Step 1-2: search the fast axis direction of the first phase delay device (10), and carry out mark, then the second phase delay device (11) is put back to the second rotating disk (4).

8. the detection method of a kind of phase delay and Polarization Dependent Loss according to claim 5, it is characterized in that: the specific implementation of searching phase delay device fast axis direction in described step 1-1, step 1-2 is: phase delay device is fixed on rotating disk, ensure and light path devices transmission axle placement altogether, rotary turnplate is until the photocurrent of photodetector output reaches maximal value.

9. application rights requires device described in 1 to carry out a method for detected phase delay and Polarization Dependent Loss, it is characterized in that, comprises the steps:

Step 1: regulate analyzer (5) parallel with the polarization direction of the polarizer (2);

Step 2: the polarization direction that regulates the first phase delay device (10), the parallel polarizer of the second phase delay device (11) (2);

Step 3: in the same way, synchronized rotation the first rotating disk (3) and the second rotating disk (4), feedback control system (7) is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π), I (k π+π/4, k π+π/4) and I (k π+pi/2, k π+pi/2), wherein k is nonnegative integer; Regulate the quick shaft direction of the second phase delay device (11), make it mutually vertical with the quick shaft direction of the first phase delay device (10);

Step 4: the zero clearing of k value is restarted to counting, synchronized rotation the first rotating disk (3) and the second rotating disk (4) in the same way,, feedback control system (7) is captured in photocurrent data I (the k π at corresponding detection wavelength place, k π+pi/2), I (k π+π/4, π/4, k π+3) and I (k π+pi/2, k π+π);

Step 5: the first phase delay device (10) and the second phase delay device (11) the phase delay angle δ that are calculated all k values place by the computing module of feedback control system (7) _1k, δ _2k, and calculate polarized dependent loss PDL _1kand PDL _2k

${\mathrm{\δ}}_1=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]+\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{\δ}}_2=\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}}\right]-\frac{1}{2}\·{\cos }^{-1}\left[\frac{4I(\mathrm{k\π}+\frac{\mathrm{\π}}{4},\mathrm{k\π}+\frac{3\mathrm{\π}}{4})-I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})-I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{2\sqrt{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})\·I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}}\right]$

${\mathrm{PDL}}_1\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π},\mathrm{k\π}+\frac{\mathrm{\π}}{2})}{I(\mathrm{k\π},\mathrm{k\π})}$

${\mathrm{PDL}}_2\left(\mathrm{indB}\right)=-5\lg \frac{I(\mathrm{k\π}+\frac{\mathrm{\π}}{2},\mathrm{k\π}+\mathrm{\π})}{I(\mathrm{k\π},\mathrm{k\π})},$ To the δ at all k values place _1k, δ _2k, PDL _1kand PDL _2kask quadratic sum, get root-mean-square valve, testing process finishes.

10. the detection method of a kind of phase delay and Polarization Dependent Loss according to claim 9, is characterized in that: between described step 1 and step 2, also comprise the steps:

Step 1-1: search the fast axis direction of the second phase delay device (11), carry out after mark, it is taken off from the second rotating disk (4);

Step 1-2: search the fast axis direction of the first phase delay device (10), and carry out mark, then the second phase delay device (11) is put back to the second rotating disk (4).