CN1266772C - Model method of detection and application for four-quadrant photo-electric detector - Google Patents

Abstract

The present invention discloses a novel, compact and practical model method for detecting and applying a four-quadrant photoelectric detector. A detector light path parameter is reversely doped out by establishing the determined functional relation between an optical path mathematic model of the four-quadrant photoelectric detector, namely an output electric signal characteristic parameter of the detector and an optical path parameter of the detector, and consequently, the method realizes that sample data is obtained without a calibrating experiment. The detector has no need to be arranged on a reference position to regulate the detector light path time after time for every time of detection. Namely, the method can realize the application that whether the self quality of the four-quadrant photoelectric detector is qualified is detected, the three-freedom degree displacement of the detector is detected, etc. Because a calibrating experiment sample does not be needed, a high-accuracy multidimensional freedom degree calibrating device has no need to be established. Because the detector has no need to carry out the light path regulation in practical application, the quality detection of the detector is greatly increased or the detection speed of the three-freedom degree displacement detection is greatly increased.

Description

Four-quadrant photo detector detects and the modelling of using

One, technical field

The invention belongs to the photodetection field, relate to modeling and characteristic parameter extraction to the four-quadrant photo detector light path, thereby the foundation of the light path parameter of the no experiment sample of realization and the corresponding relation of the signal of telecommunication, the four-quadrant photo detector that is used for other application of photodetector quality inspection and detector detects and the modelling of using.

Two, background technology

Along with the development of semiconductor progress, photoelectric detector to diversification, integrated direction development, constantly has various types of new detector to come out gradually.The continuous appearance of new device also constantly proposes the requirement of renewal to soft, the hardware of relevant signal extraction and processing.Photodetector has obtained using widely in each technical fields such as photosignal detection, photoelectric directional, photoelectricity collimation, photoelectricity aligning, optical electronic automatic tracking, photoelectric guidances as the transducer of light signal.The document that domestic relevant photo detector signal is analyzed is also few, also only rests on the detection of a certain parameter of choosing what kind of detector output signal and detector light path in existing document, and external similar reading up the literature also is difficult to find.At present, quality testing before photodetector uses, as carry out the photosurface defocusing amount and detect, its prerequisite is that detector must be installed on the reference position, and with the detection error that the deviation that reduces detector position is as far as possible brought, this makes on the one hand owing to must carry out the detector position calibration when photodetector is installed at every turn, therefore detection speed is slow, on the other hand, owing to bring wearing and tearing can for the detector checkout gear to the adjustment of detector position itself, so the checkout gear life-span is short.

The signal characteristic Parameter Extraction is an important research content in the detection technique.Itself contain a certain amount of noise inevitably in the output signal of telecommunication of four-quadrant photo detector, the information that may comprise several light path parameters in the characteristic parameter that from detector output signal, extracts simultaneously, how from the signal of telecommunication of detector output, to extract effective characteristic parameter, make that the light path parameter cross-couplings that these characteristic parameters comprised is little, the noise that comprises also is an important content of photodetector application research less.About the extraction of this characteristic parameter and and the research of the relation of light path parameter be not reported yet.Habitual experimental calibration method adopts caliberating device to provide the input variable of standard, obtain input---output characteristic, but this is difficult to realize in four-quadrant photo detector, because the output of detector and multiple relating to parameters, need set up multidimensional azimuth controllable accurate caliberating device, its process structure complexity, difficulty of processing is big, be difficult for guaranteeing precision, the cost costliness, therefore in fact all do not adopt standardization, but adopt the reference position method, would rather be tirelessly, repeated multiple times ground regulates four-quadrant photo detector and be installed in the reference position and detect.

Three, summary of the invention

The objective of the invention is to, the detection error problem that solves the detector installation difficulty and bring, and the light path parameter realizes that to the cross-couplings problem of detector output signal characteristic parameter the four-quadrant photo detector that four-quadrant photo detector just can detect in non-reference position detects and the modelling of using.

For the detection error problem that solves above-mentioned detector installation difficulty and bring, and the light path parameter is to cross-couplings problem of detector output signal characteristic parameter etc., technical thought of the present invention is, by whole four-quadrant light path is carried out optical path analysis, set up its light path Mathematical Modeling, to provide all light path parameters (σ, ρ, f, l, R, m, , η, ψ and β) and detector output signal (u in the light path _xAnd u _y) functional relation (u _x=f (f, l, R, m, , ψ, η, β), u _y=g (f, l, R, m, , ψ, η, β)).

Because with the light path parameter is independent variable, detector output signal is that the functional relation of dependent variable is non-linear, therefore is difficult to try to achieve its inverse function.But our available signal is the output signal of telecommunication u of detector usually _xAnd u _y, be some or a plurality of parameters in the light path and we will detect, therefore, be independent variable only with the light path parameter, detector output signal be dependent variable functional relation not enough, what more need is to be independent variable with the detector output signal, is the functional relation of dependent variable with the light path parameter.

The technical scheme that the present invention takes is that four-quadrant photo detector detects and the modelling of using, and is characterized in, may further comprise the steps:

1) determines detector light path parameter (hereinafter to be referred as the light path parameter), extract detector output signal of telecommunication u _xAnd u _yCharacteristic parameter (hereinafter to be referred as characteristic parameter), setting up with the light path parameter is independent variable and output signal of telecommunication u _xAnd u _yRelational expression---positive model;

The positive model functional relation:

2) produce light path parameter and output signal of telecommunication u by positive model _xAnd u _yBehind the data sample between the characteristic parameter, set up the inverse model of positive model, promptly by u _xAnd u _yCharacteristic parameter is that input variable is tried to achieve the light path parameter;

Detector light path parameters selection , ψ, η, R, f, l, β, m, wherein β is the scan angle of detector incident light, R, f, l, m are the basic parameter of detector itself:

R: detector convex lens radius;

L: the distance between detector photosurface and the convex lens;

M: the detector fitting depth of detector carriage;

F: the focal length of convex lens on the detector;

Wherein , ψ, η sign detector space mounting state depart from the relevant irrelevance in reference position, and they are:

: the position angle that detector pitching, orientation depart from;

ψ: the deviation angle that detector pitching, orientation depart from;

η: the deviation angle when detector generation roll departs from;

Also can represent, or select for use other to characterize the parameter of three dimensions state with other related angle;

The output signal of telecommunication is the output signal of telecommunication u of four area I of four-quadrant photo detector, II, III, IV _I, u _II, u _III, U _IVSynthesize gained according to following relation:

$\left\{\begin{array}{c}{u}_x=(u_I+u_{\mathrm{IV}})-(u_{\mathrm{II}}+u_{\mathrm{III}})\\ u_y=(u_I+u_{\mathrm{II}})-(u_{\mathrm{III}}+u_{\mathrm{IV}})\end{array}\right.$

Also can be

$\left\{\begin{array}{c}{u}_x=(u_{\mathrm{II}}+u_{\mathrm{III}})-(u_I+u_{\mathrm{IV}})\\ u_y=(u_{\mathrm{III}}+u_{\mathrm{IV}})-(u_I+u_{\mathrm{II}})\end{array}\right.$

Can also be u _I, u _II, u _III, u _IVOther combining form, poor as diagonal sum, or form such as phase multiplication and division.

The output signal of telecommunication u of detector _xAnd u _yIn comprised the full detail of detector light path, also has simultaneously a lot of features, these characteristic parameters are comprising different light path parameter informations, and corresponding relation therefore how to find out these characteristic parameters and the light path parameter that will detect is another important content of photodetector.For this reason, the present invention by to above-mentioned be independent variable with the light path parameter, detector output signal is that the functional relation of dependent variable is analyzed, and therefrom extracts u _xAnd u _yFour characteristic parameter a of signal _x, b _x, a _yAnd b _y, these four characteristic parameters mainly comprise respectively between detector focal distance f, photosurface and the convex lens apart from l and roll deviation angle η, orientation irrelevance, information such as pitching irrelevance.So, at first the functional relation by light path parameter and detector output signal in the photodetector test macro generates many arbitrarily samples about light path parameter and characteristic parameter, carry out function approximation by these samples by neural net or other method again, can obtain with characteristic parameter a _x, b _x, a _yAnd b _yBeing independent variable, is the approximate function relation of dependent variable with photodetector light path parameter.In follow-up actual detected, extract detector output signal u _xAnd u _yCharacteristic parameter a _x, b _x, a _yAnd b _y,, can try to achieve in the light path parameter one or several then this approximate function relational expression of characteristic parameter substitution.For example, in the defocusing amount d=f-l of the photosurface of four-quadrant photo detector detects, can be independent variable with the light path parameter at first by what set up, with the detector output signal is the defocusing amount d of the modelling of dependent variable about the photosurface of four-quadrant photo detector, detector offset , η, ψ and characteristic parameter a _x, b _x, a _yAnd b _ySample, come approximating function d=h (a with neural net then _x, b _x, a _y, b _y).So, in the actual detected of detector photosurface defocusing amount, only need from detector output signal, to extract characteristic parameter a afterwards _x, b _x, a _yAnd b _y, in the neural net that these four parameter substitutions have been trained, can try to achieve the defocusing amount d of the photosurface of four-quadrant photo detector then.

Four-quadrant photo detector of the present invention detects and the modelling of using, by setting up four-quadrant photo detector light path Mathematical Modeling, be the characteristic parameter of the detector output signal of telecommunication and the counter parameter of releasing the detector light path of definite functional relation between the detector light path parameter, thereby realize and to obtain sample data by calibration experiment, need not carry out the repeated multiple times adjusting to the detector light path for detector being installed in each the detection all in reference position, can realize the detection that the quality of four-quadrant photo detector own is whether qualified, and detector is in the application such as detection of rotary body Three Degree Of Freedom displacement.Because do not need to do the calibration experiment sample, do not need to set up high-precision multidimensional degree of freedom caliberating device.Regulate because detector does not need to carry out light path when practical application, therefore improved the detector quality testing greatly, or the detection speed of Three Degree Of Freedom displacement detection.

Four, description of drawings

Fig. 1 is the four-quadrant photo detector index path;

Fig. 2 is cut apart schematic diagram for detector photosurface four-quadrant;

Fig. 3 is the theoretical output signal of 4 quadrant detector and the real output signal of detector, wherein the negative pulse on the real output signal both sides of detector is a synchronizing signal, the model signals waveform of Fig. 3 (a) when being in the reference position for detector, Fig. 3 (b) is the model waveform waveform of detector when being in pitching and departing from, Fig. 3 (c) is the model signal output waveform of detector when being in the orientation and departing from, Fig. 3 (d) is the model signal output waveform of detector when being in roll and departing from, Fig. 3 (f) is the actual signal waveform of detector when being in the reference position, just above-mentioned three kinds of signal output waveforms that depart from when taking place simultaneously;

Fig. 3 (g) is the real output signal of a certain given four-quadrant photo detector, Fig. 3 (e) is for after recording deflecting angle , ψ, η and the parameter l of this detector by the four-quadrant photo detector modeling, the theoretical output signal of the resulting detector of these four parameter substitution master moulds.Relatively the real output signal of the theoretical output signal of 4 quadrant detector and detector as can be seen, it is consistent that the output of the theory of detector is exported with reality.

Fig. 4 is an independent variable for approaching with the characteristic parameter, is the neural network structure figure of the function of dependent variable with certain light path parameter.

Five, specific embodiments

The present invention is described in further detail below in conjunction with specific embodiments that accompanying drawing and inventor provide.

According to technical scheme of the present invention, be that example illustrates how to realize that by modelling the no experiment sample of detector detects with the defocusing amount d=f-l that detects the four-quadrant photo detector photosurface.

1, the light path of four-quadrant photo detector such as accompanying drawing 1, four-quadrant photosurface such as Fig. 2.By analysis, can set up four-quadrant photo detector about being independent variable, with u with σ, ρ, f, l, R, m, , η, ψ and β to this light path _xAnd u _yBe the functional relation of dependent variable, and extract four characteristic parameter: u _xSignal is at the tangent slope a of zero crossing _xWith intercept b _x, u _ySignal is at the tangent slope a of zero crossing _yWith intercept b _y

$\left\{\begin{array}{c}{u}_x=\mathrm{\σ\ρ\π}{R}^2\sqrt{1-{\cos }^2\mathrm{\φ}}(\arccos \frac{{\mathrm{MO}}_2\sin (\mathrm{\π}/2-\mathrm{\η})}{R}/\frac{\mathrm{\π}}{2}-1)---\left(1\right)\\ u_y=\mathrm{\σ\ρ\π}{R}^2\sqrt{1-{\cos }^2\mathrm{\φ}}(\arccos \frac{O_{2}N\sin (\frac{\mathrm{\π}}{2}-\mathrm{\η})}{R}/\frac{\mathrm{\π}}{2}-1)---\left(2\right)\end{array}\right.$

Wherein

cos ²φ＝{sinβ-cos[β+arcsin(sinψsin)-arccos(sinsinψ)]} ²

+cos ²[arccos(sinsinψ)-β]

$\∠{\mathrm{RO}}_{3}S=\arccos \frac{O_3{R}^2+O_3{S}^2-R{S}^2}{2O_{3}R\·O_{3}S}$

$O_{3}R=\sqrt{O_3{S}^2+R{S}^2-2O_{3}S\·\mathrm{RS}\cos (\mathrm{\ψ}+\mathrm{\η})}$

O ₃S＝ltanψ

Parameter declaration:

F: four-quadrant photo detector focal length of convex lens;

L: the distance between four-quadrant photo detector photosurface and the convex lens;

R: four-quadrant photo detector convex lens radius;

: four-quadrant photo detector deviation position;

ψ: four-quadrant photo detector deviation angle;

η: four-quadrant photo detector roll deflecting angle;

M: four-quadrant photo detector is contained in half that it reprints length on support;

σ: photosurface photoelectric conversion factors;

ρ: the illuminance of detector incident light;

β: the deflecting angle of detector incident light.

Especially,

(1) when ψ=0, η=0 o'clock, detector is in the reference position;

This moment u _yBe converted into: u _y=0, u _xBe converted into:

Wherein $r=R\frac{f-l}{f},$ s＝|ltanβ|，

With u _xAsk local derviation to get to β: $a_x={\mathrm{du}}_x/\mathrm{d\β}{|}_{\mathrm{\β}=0}=-\mathrm{\π\τ\ρ\σ}{R}^2(f-l)/f.$ Because f-l is the defocusing amount of detector photosurface, other is definite value, therefore, under base case, u _xThe slope a that signal is located at its zero crossing (β=0) _xBe directly proportional with the photosurface defocusing amount, utilize this characteristic can be according to u _xThe slope of zero crossing detects the defocusing amount d=f-l or the focal length of convex lens f of detector, but detected parameters l similarly certainly.The theoretical output signal of detector is shown in Fig. 3 (a) at this moment.

(2) when =pi/2 or 3 pi/2s, η=0, but ψ ≠ 0 o'clock, detector is in the pitching deviation position.This moment u _yBe converted into:

u _xBe converted into: $u_x=\mathrm{\τ\ρ\σ}[2r^2\arccos (s/r)-2s\sqrt{r^2-s^2}-{\mathrm{\πr}}^2]\·\sin \∠A^{\′}\mathrm{OE}$

Wherein $\∠A^{\′}\mathrm{OE}=\arccos \frac{\sqrt{{\tan }^2\mathrm{\ψ}+{\tan }^2\mathrm{\β}}}{\sec \mathrm{\β}},$ t＝(l-m)tanψ

Usually the value of ψ and β is all smaller, so sin ∠ A`OE ≈ 1, and uy is approximately straight line, and the information spinner of ψ will be reflected in u _yIntercept b _yOn.The output waveform of detector is shown in Fig. 3 (b) at this moment.

(3) as =0 or π, η=0, but ψ ≠ 0 o'clock, detector is in the orientation deviation position.This moment u _yBe converted into u _y=0, u _xBe converted into:

When β=0, u _x≠ 0, so ψ is reflected in u _xThe side-play amount of zero crossing also is u _xThe intercept b of zero crossing tangent line _xOn.The output of detector is shown in Fig. 3 (c) at this moment.

(4) when η ≠ 0, but ψ=0 o'clock, detector is in the roll deviation position.This moment u _xBe converted into:

u _yBe converted into:

This moment u _yValue change with the variation of β because u _yOther parameter is almost constant in the expression formula, so the message reflection of η is at u _ySlope a _yOn.

2, make about characteristic parameter a _x, b _x, a _yAnd b _ySample with detector defocusing amount d

Is independent variable setting up above-mentioned with σ, ρ, f, l, R, m, , η, ψ and β, with u _xAnd u _yBehind the functional relation (1) of dependent variable, (2), can (σ, ρ, f, R, m be constant here by changing arbitrarily one or several parameter among , η, ψ, f, the l, the parameter that needs to detect is f-l, but have interference volume , η and ψ), try to achieve about these parameters and characteristic parameter a by relational expression (1), (2) _x, b _x, a _yAnd b _ySample.

3, foundation is about the inverse model of characteristic parameter and detector defocusing amount

Can approach with a by neural net by these samples _x, b _x, a _yAnd b _yBe independent variable, with functions that a plurality of parameters are dependent variable such as , η, ψ, f or , η, ψ, l.Thereby realize the detection of detector light path parameter.Used neural network model such as accompanying drawing 4 in the detection of detector photosurface defocusing amount.

4, experiment actual measurement

With the inverse model of setting up in 3 different four-quadrant photo detectors are carried out repeatability actual measurement, detection data such as following table about d=f-l.Similarly, if necessary, also can record parameter , η and ψ with identical method.

Three four-quadrant photo detector photosurface defocusing amount d duplicate detection tables of data (mm)

Claims (4)

1. a four-quadrant photo detector detects and the modelling of using, and it is characterized in that: may further comprise the steps:

1) determines detector light path parameter, extract detector output signal of telecommunication u _xAnd u _yCharacteristic parameter, setting up with the light path parameter is independent variable and output signal of telecommunication u _xAnd u _yRelational expression---positive model;

The positive model functional relation:

2) produce light path parameter and output signal of telecommunication u by positive model _xAnd u _yBehind the data sample between the characteristic parameter, set up the inverse model of positive model, promptly by u _xAnd u _yCharacteristic parameter is that input variable is tried to achieve the light path parameter;

Detector light path parameters selection , ψ, η, R, f, l, β, m, wherein β is the scan angle of detector incident light, R, f, l, m are the basic parameter of detector itself:

R: detector convex lens radius;

L: the distance between detector photosurface and the convex lens;

M: the detector fitting depth of detector carriage;

F: the focal length of convex lens on the detector;

Wherein , ψ, η sign detector space mounting state depart from the relevant irrelevance in reference position, and they are:

: the position angle that detector pitching, orientation depart from;

ψ: the deviation angle that detector pitching, orientation depart from;

η: the deviation angle when detector generation roll departs from;

The output signal of telecommunication is the output signal of telecommunication u of four area I of four-quadrant photo detector, II, III, IV _I, u _II, u _III, u _IVSynthesize gained according to following relation:

$\left\{\begin{array}{c}{u}_x=(u_I+u_{\mathrm{IV}})-(u_{\mathrm{II}}+u_{\mathrm{III}})\\ u_y=(u_I+u_{\mathrm{II}})-(u_{\mathrm{III}}+u_{\mathrm{IV}})\end{array}\right.$

Or

$\left\{\begin{array}{c}{u}_x=(u_{\mathrm{II}}+u_{\mathrm{III}})-(u_I+u_{\mathrm{IV}})\\ u_y=(u_{\mathrm{III}}+u_{\mathrm{IV}})-(u_I+u_{\mathrm{II}})\end{array}\right..$

2. four-quadrant photo detector according to claim 1 detects and the modelling of using, and it is characterized in that: described detector output signal of telecommunication u _xAnd u _yThe synthetic output signal of telecommunication u of characteristic parameter extraction _xAnd u _yCharacteristic parameter be u _xZero crossing tangent slope a _xIntercept b _xu _yZero crossing tangent slope a _yIntercept b _yOr coordinate figure.

3. four-quadrant photo detector according to claim 1 detects and the modelling of using, and described positive model relational expression can also be following relational expression:

$\left\{\begin{array}{c}{u}_x=\mathrm{\σ\ρ\π}{R}^2\sqrt{1-{\cos }^2\mathrm{\φ}}(\arccos \frac{M{O}_2\sin (\mathrm{\π}/2-\mathrm{\η})}{R}/\frac{\mathrm{\π}}{2}-1)---\left(1\right)\\ u_y=\mathrm{\σ\ρ\π}{R}^2\sqrt{1-{\cos }^2\mathrm{\φ}}(\arccos \frac{O_{2}N\sin (\frac{\mathrm{\π}}{2}+\mathrm{\η})}{R}/\frac{\mathrm{\π}}{2}-1)---\left(2\right)\end{array}\right.$

Wherein

cos ²φ＝{sinβ-cos[β+arcsin(sinψsin)-arccos(sinsinψ)]} ²

+cos ²[arccos(sinsinψ)-β]

$\∠{\mathrm{RO}}_{3}S=\arccos \frac{O_3{R}^2+O_3{S}^2-{\mathrm{RS}}^2}{{2O}_{3}R\·O_{3}S}$

$O_{3}R=\sqrt{O_3{S}^2+{\mathrm{RS}}^2-{2O}_{3}S\·\mathrm{RS}\cos (\mathrm{\ψ}+\mathrm{\η})}$

O ₃S＝ltanψ

Parameter declaration:

F: four-quadrant photo detector focal length of convex lens;

L: the distance between four-quadrant photo detector photosurface and the convex lens;

R: four-quadrant photo detector convex lens radius

: four-quadrant photo detector deviation position

ψ: four-quadrant photo detector deviation angle

η: four-quadrant photo detector roll deflecting angle

M: four-quadrant photo detector is contained in half that it reprints length on support

σ: photosurface photoelectric conversion factors

ρ: the illuminance of detector incident light

β: the deflecting angle of detector incident light

Especially:

(1) when ψ=0, η=0 o'clock, detector is in the reference position, this moment u _yBe converted into: u _y=0, u _xBe converted into:

Wherein $r=R\frac{f-l}{f},$ s＝|ltanβ|，

With u _xAsk local derviation to get to β: a _x=du _x/ d β | _β=0=-π τ ρ σ R ²(f-l)/f; Because f-l is the defocusing amount of detector photosurface, other is definite value, therefore, under base case, u _xSignal is at its zero crossing, i.e. the slope a at β=0 place _xBe directly proportional with the photosurface defocusing amount, utilize this characteristic can be according to u _xThe slope of zero crossing detects the defocusing amount d=f-l or the focal length of convex lens f of detector, but detected parameters l similarly certainly;

(2) when =pi/2 or 3 pi/2s, η=0, but ψ ≠ 0 o'clock, detector is in the pitching deviation position, this moment u _yBe converted into:

u _xBe converted into: $u_x=\mathrm{\τ\ρ\σ}[{2r}^2\arccos (s/r)-2s\sqrt{r^2-s^2}-{\mathrm{\πr}}^2]\·\sin \∠A^{\′}\mathrm{OE}$

Wherein $\∠A^{\′}\mathrm{OE}=\arccos \frac{\sqrt{{\tan }^2\mathrm{\ψ}+{\tan }^2\mathrm{\β}}}{\sec \mathrm{\β}},$ t＝(l-m)tanψ

Usually the value of ψ and β is all smaller, so sin ∠ A`OE ≈ 1, u _yBe approximately straight line, the information spinner of ψ will be reflected in u _yIntercept b _yOn;

(3) as =0 or π, η=0, but ψ ≠ 0 o'clock, detector is in the orientation deviation position, this moment u _yBe converted into u _y=0, u _xBe converted into:

When β=0, u _x≠ 0, so ψ is reflected in u _xThe side-play amount of zero crossing also is u _xThe intercept b of zero crossing tangent line _xOn;

(4) when η ≠ 0, but ψ=0 o'clock, detector is in the roll deviation position; This moment u _xBe converted into:

u _yBe converted into:

This moment u _yValue change with the variation of β because u _yOther parameter is almost constant in the expression formula, so the message reflection of η is at u _ySlope a _yOn;

Make characteristic parameter a _x, b _x, a _yAnd b _yWith the sample of detector defocusing amount d be:

Is independent variable setting up above-mentioned with σ, ρ, f, l, R, m, , η, ψ and β, with u _xAnd u _yBehind the functional relation (1) of dependent variable, (2), can try to achieve about these parameters and characteristic parameter a by relational expression (1), (2) by changing one or several parameter among , η, ψ, f, the l arbitrarily _x, b _x, a _yAnd b _ySample.

4. four-quadrant photo detector according to claim 1 detects and the modelling of using, it is characterized in that, the data sample that is generated by positive model has been set up the inverse model of positive model, and the foundation of inverse model can be adopted the neural net method, can be approached with a by neural net by these samples _x, b _x, a _yAnd b _yBeing independent variable, is the function of dependent variable with , η, ψ, f or , η, ψ, one of l and a plurality of parameter, thereby realizes the detection of detector light path parameter.

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