CN104865050A - Focusing performance analysis method for grazing incidence optical system based on X-ray optical simulation - Google Patents

Abstract

The invention provides a focusing performance analysis method for a grazing incidence optical system based on X-ray optical simulation. The method fully considers characteristic information of X-ray photon energy and reflectivity, irons out a defect in the prior art that only single-energy X-ray photons are considered and the reflectivity is not considered, can achieve engineering actual condition closer to X-ray pulsar navigation apparatus, and improves the efficiency of X-ray optical simulation and analysis. The method can achieve the analysis of the focusing performance of an optical system under the conditions of thermal deformation, structural deformation or thermal-structural coupling deformation, and obtains the mean square root radiuses of a disc of confusion of the optical system, 100% energy concentration ratio and 50% energy concentration ratio under different conditions, thereby achieving the quantification of impact degree on the focusing performance of the optical system from different deformations, and providing support for the reliability design and optimization of a product.

Description

Based on the grazing incidence optics system focusing performance analytical approach of X ray optical simulation

Technical field

The present invention relates to spacecraft product design technology field, particularly based on the grazing incidence optics system focusing performance analytical approach of X ray optical simulation.

Background technology

Along with the needs of the driving of military requirement, resource detection and Science Explorations, X-ray pulsar airmanship obtains develop rapidly.X-ray pulsar navigating instrument is as the core load in this field, the performance index such as its spatial resolution, temporal resolution, navigation accuracy improve constantly, and the lifting of navigating instrument performance requirement also determines and proposes more harsh requirement to the optical system of whole device and the degree of stability of supporting construction and size.Meanwhile, along with the development of Small Satellite Technology, but sustainable growth is required to the light weight degree of X-ray pulsar navigating instrument.And the design of X-ray pulsar navigating instrument relates to light, machine, hot multiple subject, be a multidisciplinary interaction, the process of choosing comprehensively.Therefore, how optical simulation analysis is carried out to X-ray pulsar guider and focusing performance evaluation is the basis of developing high capability instrument.

Glancing incidence type X-ray optical system, compared with traditional optical system, has following difference: (1) glancing incidence cirtical angle of total reflection increases non-linear reduction with energy; (2) X ray of particular energy, reflectivity increases non-linear reduction with incident angle; (3) grazing angle one timing, reflectivity falls sharply with the increase of energy is non-linear; (4) harsh to optical lens surface roughness requirements, must reach below 1nm could be totally reflected, and therefore requires high to camera lens face shape.

And existing X ray optical simulation and evaluation method still adopt traditional optical simulation for other wave band (as visible ray, infrared, ultraviolet etc.) and evaluation method mostly.Do not consider the reflectivity of X ray and the relation of incident angle and X-ray energy, this will cause two problems: (1) existing optical simulation method or business software can only analyze the X ray of certain single energy at every turn, and cannot reflectivity information be considered, for the Wolter-I type x-ray telescope of 0.1-10keV wide energy section, its workload is huge, seriously hinders the application in aerospace engineering.(2) traditional optics evaluating method is adopted can not really to reflect X-ray focusing performance, because for broadband X ray, due to its continuity, discrete emulation mode is adopted to be unfavorable for Project Realization, secondly owing to not considering the relation between energy and reflectivity, it focuses on evaluation method cannot reflect actual conditions strictly according to the facts.

Summary of the invention

Object of the present invention with overcome the deficiencies in the prior art, provide the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation.The method has taken into full account the characteristic information of x-ray photon energy and reflectivity, avoid in prior art and only consider single energy x-ray photon, and do not consider the defect of reflectivity, the engineering practice closer to X-ray pulsar guider can be realized, improve the efficiency of X ray optical simulation.

Above-mentioned purpose of the present invention is realized by following technical scheme:

Based on the grazing incidence optics system focusing performance analytical approach of X ray optical simulation, comprise the following steps:

(1), arrange the incoming position of P x-ray photon on optical lens inside surface, photon energy and grazing angle, wherein, the incoming position coordinate of p photon is respectively x _p, y _p, z _p, the initial point of described coordinate system is set as detector center, and Z axis is set as the central axis of optical lens; The photon energy of p photon is E _p, E _pat the energy range E of setting _min~ E _maxinterior stochastic distribution; The grazing angle of p photon is θ _p, θ _pin the angular range, theta of setting _min~ θ _maxinterior stochastic distribution; P=1,2 ..., P, P be setting x-ray photon sample size;

(2) the x-ray photon incoming position coordinate, according to step (1) arranged, calculate the camera lens radius-of-curvature of each described photon at optical lens inside surface incidence point place, and described incidence point is to the distance of optical lens central axis; Wherein, Υ _pit is the camera lens radius-of-curvature at p photon incidence point place; d _pbe that p photon is in the distance of optical lens inside surface incidence point to optical lens central axis; P=1,2 ..., P; Specific formula for calculation is as follows:

$d_p=\sqrt{x_p^2+y_p^2};$

(3) the camera lens radius-of-curvature of the x-ray photon, according to step (2) calculated at optical lens inside surface incidence point place and incidence point, to the distance of optical lens central axis, calculate the actual grazing angle of each x-ray photon; Wherein, the actual grazing angle calculating p x-ray photon is p=1,2 ..., P;

(4), calculate the critical angle of incidence of described photon according to the photon energy of each x-ray photon, wherein, the critical angle of incidence calculating p x-ray photon is φ _p, p=1,2 ..., P;

(5), by the actual grazing angle of the critical angle of incidence of each x-ray photon and described photon compare, determine whether described photon full transmitting occurs, and count there is the full photon launched, obtain the total number of light photons N arriving detector _total;

(6), N is obtained to step (5) statistics _totalthe individual x-ray photon that total reflection occurs, calculates as follows, obtains the reflection angle of each described photon on camera lens inside surface:

Wherein, α _qbe q the reflection angle of x-ray photon on camera lens inside surface that total reflection occurs, be q the actual grazing angle that the x-ray photon of total reflection occurs, θ _q' be q the grazing angle that the x-ray photon of total reflection occurs; Wherein, q=1,2 ..., N _total;

(7) reflection angle of each described photon on camera lens inside surface, according to step (6) calculated, calculates the component velocity that each photon is propagated in the radial and axial directions; Then according to the Z coordinate figure of axial component velocity, focal length and photon, the flight time that each described photon arrives detector focal plane is calculated; Calculate each photon that total reflection occurs according to the equation of motion again and arrive the coordinate figure behind detector focal plane; Wherein, calculate q the x-ray photon that total reflection occurs and arrive the X-coordinate behind detector focal plane and Y-coordinate is respectively q=1,2 ..., N _total;

(8), calculate X ray optical focus performance parameter, specific formula for calculation is as follows:

$\mathrm{RMS}=\sqrt{\frac{\underset{q=1}{\overset{N_{\mathrm{total}}}{\mathrm{\Σ}}}{r}_q^2}{N_{\mathrm{total}}}}$

Wherein, RMS is the disc of confusion root mean square radii of X ray optical focus performance parameter; r _qbe the distance that q the x-ray photon that total reflection occurs arrives between the position behind detector focal plane and detector center, namely $r_q=\sqrt{{{\hat{x}}_q}^2+{{\hat{y}}_q}^2}.$

The above-mentioned grazing incidence optics system focusing performance analytical approach based on X ray optical simulation, in step (3), the actual grazing angle of p x-ray photon computing formula as follows:

The above-mentioned grazing incidence optics system focusing performance analytical approach based on X ray optical simulation, in step (4), the critical angle of incidence φ of p x-ray photon _pcomputing formula as follows:

${\mathrm{\φ}}_p=\frac{0.00727\×1.24}{E_p}\sqrt{f_1}$

Wherein, f ₁for the dispersion factor of the optical lens material of setting.

The above-mentioned grazing incidence optics system focusing performance analytical approach based on X ray optical simulation, in step (5), determine whether x-ray photon occurs be totally reflected and count by the following method: if the actual grazing angle of p x-ray photon is greater than the critical angle of incidence of described photon, namely then judge that described photon occurs be totally reflected and arrive detector, then will arrive the total number of light photons N of detector _totaladd 1, i.e. N _total=N _total+ 1; Wherein set N _totalinitial value be 0; P=1,2 ..., P.

The above-mentioned grazing incidence optics system focusing performance analytical approach based on X ray optical simulation, in step (7), according to the reflection angle of each described photon on camera lens inside surface that step (6) calculates, calculate the component velocity that each photon is propagated in the radial and axial directions; Then according to the Z coordinate figure of axial component velocity, focal length and photon, the flight time that each described photon arrives detector focal plane is calculated; Calculate each photon that total reflection occurs according to the equation of motion again and arrive the coordinate figure behind detector focal plane; Concrete computation process is as follows:

(7a), calculate the component velocity of x-ray photon along optical axis direction and radial direction, specific formula for calculation is as follows:

V _q,1＝V ₀*cos(α _q)；

V _q,2＝V ₀*sin(α _q)；

Wherein, V _{q, 1}be q the component velocity of x-ray photon along optical axis direction that total reflection occurs, V _{q, 2}be q the x-ray photon component velocity radially that total reflection occurs, V ₀for the light velocity of setting; Wherein, q=1,2 ..., N _total;

(7b), the flight time that each x-ray photon that total reflection occurs arrives detector focal plane is calculated:

$T_q=\frac{f-{z_q}^{\′}}{V_{q,1}};$

Wherein, T _qbe q the flight time that the x-ray photon arrival detector focal plane of total reflection occurs, f is the optical system focal length of setting; z _q' be q occur total reflection x-ray photon original incident time Z coordinate; Wherein, q=1,2 ..., N _total;

(7c), calculate each occur total reflection x-ray photon arrive detector focal plane time position coordinates, specific formula for calculation is as follows:

${\hat{x}}_q={x_q}^{\′}-V_{q,2}\×T_q;$

${\hat{y}}_q={y_q}^{\′}-V_{q,2}\×T_q;;$

Wherein, be respectively the X-coordinate behind q the x-ray photon arrival detector focal plane occurring to be totally reflected and Y-coordinate; x _q' and y _q' be respectively q occur total reflection x-ray photon original incident time X-coordinate and Y-coordinate; Wherein, q=1,2 ..., N _total.

The above-mentioned grazing incidence optics system focusing performance analytical approach based on X ray optical simulation, according to the photon number N that total reflection occurs _totaland the ratio calculation between the x-ray photon sample size P of setting obtains 100% encircled energy of x-ray photon

The above-mentioned grazing incidence optics system focusing performance analytical approach based on X ray optical simulation, calculate the X-coordinate behind the x-ray photon arrival detector focal plane that total reflection occurs and Y-coordinate in step (7) after, with detector center for the center of circle, and with for radius determines a circle on detector focal plane, add up the photon number entered in described circle namely described in position after individual x-ray photon arrives detector focal plane and the distance between detector center are less than or equal to

The above-mentioned grazing incidence optics system focusing performance analytical approach based on X ray optical simulation, is less than or equal to according to the distance between the position behind arrival detector focal plane and detector center photon number and the ratio between the x-ray photon sample size P of setting, calculates 50% encircled energy of x-ray photon ${\mathrm{\η}}^{\′}=\frac{N_{R_E/2}}{P}.$

The present invention compared with prior art, has the following advantages:

(1), the present invention has taken into full account the characteristic information of x-ray photon energy and reflectivity, avoid in prior art and only consider single energy x-ray photon, and do not consider the defect of reflectivity, the engineering practice closer to X-ray pulsar guider can be realized, improve the efficiency of X ray optical simulation.

(2) the present invention is based on the distinctive total reflection theory of X ray and cover tower calot's method, ray tracing is carried out to all x-ray photons of stochastic production, according to flight time and the X in detector plane, the component velocity in Y-direction, its position on detector focal plane of real time discriminating, achieves X ray glancing incidence tracking control of full process;

(3), the present invention is directed to the x-ray photon overall process ray tracing of large sample, Corpus--based Method thought is added up the quantity of the x-ray photon of arrival detector focal plane and in-position thereof, disc of confusion root mean square radii is adopted to carry out focusing performance evaluation to it, thermal deformation, structural deformation and coupling deformation are quantized to the influence degree of X-ray pulsar guider focusing performance, for follow-up complete machine optimal design provides theory support.

Accompanying drawing explanation

Fig. 1 is the process flow diagram of the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation of the present invention.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail:

In the simulation analysis of X-ray pulsar guider, because x-ray photon is different from the photon of its all band, its reflectivity and its energy closely related, and traditional emulation mode does not consider energy and this two large characteristic of reflectivity of X ray.Therefore, in order to the engineering practice closer to X-ray pulsar guider, the invention provides the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation.

Analysis process figure as shown in Figure 1, the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation of the present invention, comprises the following steps:

(1), arrange the incoming position of P x-ray photon on optical lens inside surface, photon energy and grazing angle, wherein, the incoming position coordinate of p photon is respectively x _p, y _p, z _p, the initial point of described coordinate system is set as detector center, and Z axis is set as the central axis of optical lens; The photon energy of p photon is E _p, E _pat the energy range E of setting _min~ E _maxinterior stochastic distribution; The grazing angle of p photon is θ _p, θ _pin the angular range, theta of setting _min~ θ _maxinterior stochastic distribution; P=1,2 ..., P, P be setting x-ray photon sample size;

(2) the x-ray photon incoming position coordinate, according to step (1) arranged, calculate the camera lens radius-of-curvature of each described photon at optical lens inside surface incidence point place, and described incidence point is to the distance of optical lens central axis; Wherein, Υ _pit is the camera lens radius-of-curvature at p photon incidence point place; d _pbe that p photon is in the distance of optical lens inside surface incidence point to optical lens central axis; P=1,2 ..., P; Because optical frames women's head-ornaments shape formula is: therefore in the present invention, the formula of Calculation of curvature radius is set as: and set $d_p=\sqrt{x_p^2+y_p^2};$

(3) the camera lens radius-of-curvature of the x-ray photon, according to step (2) calculated at optical lens inside surface incidence point place and incidence point, to the distance of optical lens central axis, calculate the actual grazing angle of each x-ray photon; Specific formula for calculation is as follows:

Wherein, be the actual grazing angle of p x-ray photon, p=1,2 ..., P;

(4), calculate the critical angle of incidence of described photon according to the photon energy of each x-ray photon, specific formula for calculation is as follows:

${\mathrm{\φ}}_p=\frac{0.00727\×1.24}{E_p}\sqrt{f_1};p=\mathrm{1,2},...,P;$

Wherein, φ _pit is the critical angle of incidence of p x-ray photon; f ₁for the dispersion factor of the optical lens material of setting.

(5), by the actual grazing angle of the critical angle of incidence of each x-ray photon and described photon compare, determine whether described photon full transmitting occurs, and count there is the full photon launched, obtain the total number of light photons N arriving detector _total; Specific implementation process is as follows: if the actual grazing angle of p x-ray photon is greater than the critical angle of incidence of described photon, namely then judge that described photon occurs be totally reflected and arrive detector, then will arrive the total number of light photons N of detector _totaladd 1, i.e. N _total=N _total+ 1; Wherein set N _totalinitial value be 0; P=1,2 ..., P.

(6), N is obtained to step (5) statistics _totalthe individual x-ray photon that total reflection occurs, calculates as follows, obtains the reflection angle of each described photon on camera lens inside surface:

Wherein, α _qbe q the reflection angle of x-ray photon on camera lens inside surface that total reflection occurs, be q the actual grazing angle that the x-ray photon of total reflection occurs, θ _q' be q the grazing angle that the x-ray photon of total reflection occurs; Wherein, q=1,2 ..., N _total;

(7) reflection angle of each described photon on camera lens inside surface, according to step (6) calculated, calculates the component velocity that each photon is propagated in the radial and axial directions; Then according to the Z coordinate figure of axial component velocity, focal length and photon, the flight time that each described photon arrives detector focal plane is calculated; Calculate each photon that total reflection occurs according to the equation of motion again and arrive the coordinate figure behind detector focal plane; Wherein, calculate q the x-ray photon that total reflection occurs and arrive the X-coordinate behind detector focal plane and Y-coordinate is respectively q=1,2 ..., N _total;

Concrete computation process is as follows:

(7a), calculate the component velocity of x-ray photon along optical axis direction and radial direction, specific formula for calculation is as follows:

V _q,1＝V ₀*cos(α _q)；

V _q,2＝V ₀*sin(α _q)；

Wherein, V _{q, 1}be q the component velocity of x-ray photon along optical axis direction that total reflection occurs, V _{q, 2}be q the x-ray photon component velocity radially that total reflection occurs, V ₀for the light velocity of setting; Wherein, q=1,2 ..., N _total;

(7b), the flight time that each x-ray photon that total reflection occurs arrives detector focal plane is calculated:

$T_q=\frac{f-{z_q}^{\′}}{V_{q,1}};$

Wherein, T _qbe q the flight time that the x-ray photon arrival detector focal plane of total reflection occurs, f is the optical system focal length of setting; z _q' be q occur total reflection x-ray photon original incident time Z coordinate; Wherein, q=1,2 ..., N _total;

(7c), calculate each occur total reflection x-ray photon arrive detector focal plane time position coordinates, specific formula for calculation is as follows:

${\hat{x}}_q={x_q}^{\′}-V_{q,2}\×T_q;$

${\hat{y}}_q={y_q}^{\′}-V_{q,2}\×T_q;;$

Wherein, be respectively the X-coordinate behind q the x-ray photon arrival detector focal plane occurring to be totally reflected and Y-coordinate; x _q' and y _q' be respectively q occur total reflection x-ray photon original incident time X-coordinate and Y-coordinate; Wherein, q=1,2 ..., N _total.

(8), calculate X ray optical focus performance parameter, specific formula for calculation is as follows:

$\mathrm{RMS}=\sqrt{\frac{\underset{q=1}{\overset{N_{\mathrm{total}}}{\mathrm{\Σ}}}{r}_q^2}{N_{\mathrm{total}}}}$

Wherein, RMS is the disc of confusion root mean square radii as X ray optical focus performance parameter; r _qbe the distance that q the x-ray photon that total reflection occurs arrives between the position behind detector focal plane and detector center, namely $r_q=\sqrt{{{\hat{x}}_q}^2+{{\hat{y}}_q}^2}.$

(9), according to the photon number N that total reflection occurs _totaland the ratio calculation between the x-ray photon sample size P of setting obtains 100% encircled energy of x-ray photon

(10), with detector center for the center of circle, and with for radius determines a circle on detector focal plane, add up the photon number entered in described circle namely described in position after individual x-ray photon arrives detector focal plane and the distance between detector center are less than or equal to

(11), be less than or equal to according to the distance between the position behind arrival detector focal plane and detector center photon number and the ratio between the x-ray photon sample size P of setting, calculates 50% encircled energy of x-ray photon

Adopt grazing incidence optics system focusing performance analytical approach of the present invention, can analyze the optics into focus performance in thermal deformation, structural deformation or thermal-structure coupled deformation situation respectively, obtain the disc of confusion root mean square radii of optical system under different situations, 100% encircled energy and 50% encircled energy, thus quantized the influence degree of different deformation to optics into focus performance, for the reliability design of product and optimization provide theories integration.

The above; be only the present invention's embodiment, but protection scope of the present invention is not limited thereto, is anyly familiar with those skilled in the art in the technical scope that the present invention discloses; the change that can expect easily or replacement, all should be encompassed within protection scope of the present invention.

The content be not described in detail in instructions of the present invention belongs to the known technology of professional and technical personnel in the field.

Claims (8)

1., based on the grazing incidence optics system focusing performance analytical approach of X ray optical simulation, it is characterized in that comprising the following steps:

(1), arrange the incoming position of P x-ray photon on optical lens inside surface, photon energy and grazing angle, wherein, the incoming position coordinate of p photon is respectively x _p, y _p, z _p, the initial point of described coordinate system is set as detector center, and Z axis is set as the central axis of optical lens; The photon energy of p photon is E _p, E _pat the energy range E of setting _min~ E _maxinterior stochastic distribution; The grazing angle of p photon is θ _p, θ _pin the angular range, theta of setting _min~ θ _maxinterior stochastic distribution; P=1,2 ..., P, P be setting x-ray photon sample size;

(2) the x-ray photon incoming position coordinate, according to step (1) arranged, calculate the camera lens radius-of-curvature of each described photon at optical lens inside surface incidence point place, and described incidence point is to the distance of optical lens central axis; Wherein, it is the camera lens radius-of-curvature at p photon incidence point place; d _pbe that p photon is in the distance of optical lens inside surface incidence point to optical lens central axis; P=1,2 ..., P; Specific formula for calculation is as follows:

$d_p=\sqrt{x_p^2+y_p^2};$

(3) the camera lens radius-of-curvature of the x-ray photon, according to step (2) calculated at optical lens inside surface incidence point place and incidence point, to the distance of optical lens central axis, calculate the actual grazing angle of each x-ray photon; Wherein, the actual grazing angle calculating p x-ray photon is p=1,2 ..., P;

(4), calculate the critical angle of incidence of described photon according to the photon energy of each x-ray photon, wherein, the critical angle of incidence calculating p x-ray photon is φ _p, p=1,2 ..., P;

(5), by the actual grazing angle of the critical angle of incidence of each x-ray photon and described photon compare, determine whether described photon full transmitting occurs, and count there is the full photon launched, obtain the total number of light photons N arriving detector _total;

(6), N is obtained to step (5) statistics _totalthe individual x-ray photon that total reflection occurs, calculates as follows, obtains the reflection angle of each described photon on camera lens inside surface:

Wherein, α _qbe q the reflection angle of x-ray photon on camera lens inside surface that total reflection occurs, be q the actual grazing angle that the x-ray photon of total reflection occurs, θ _q' be q the grazing angle that the x-ray photon of total reflection occurs; Wherein, q=1,2 ..., N _total;

(7) reflection angle of each described photon on camera lens inside surface, according to step (6) calculated, calculates the component velocity that each photon is propagated in the radial and axial directions; Then according to the Z coordinate figure of axial component velocity, focal length and photon, the flight time that each described photon arrives detector focal plane is calculated; Calculate each photon that total reflection occurs according to the equation of motion again and arrive the coordinate figure behind detector focal plane; Wherein, calculate q the x-ray photon that total reflection occurs and arrive the X-coordinate behind detector focal plane and Y-coordinate is respectively q=1,2 ..., N _total;

(8), calculate X ray optical focus performance parameter, specific formula for calculation is as follows:

$\mathrm{RMS}=\sqrt{\frac{\underset{q=1}{\overset{N_{\mathrm{total}}}{\mathrm{\Σ}}}{r}_q^2}{N_{\mathrm{total}}}}$

Wherein, RMS is the disc of confusion root mean square radii of X ray optical focus performance parameter; r _qbe the distance that q the x-ray photon that total reflection occurs arrives between the position behind detector focal plane and detector center, namely $r_q=\sqrt{{{\hat{x}}_q}^2+{{\hat{y}}_q}^2}.$

2. the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation according to claim 1, is characterized in that: in step (3), the actual grazing angle of p x-ray photon computing formula as follows:

p＝1、2、…、P。

3. the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation according to claim 1, is characterized in that: in step (4), the critical angle of incidence φ of p x-ray photon _pcomputing formula as follows:

${\mathrm{\φ}}_p=\frac{0.00727\×1.24}{E_p}\sqrt{f_1}$

Wherein, f ₁for the dispersion factor of the optical lens material of setting.

4. the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation according to claim 1, it is characterized in that: in step (5), determine whether x-ray photon occurs be totally reflected and count by the following method: if the actual grazing angle of p x-ray photon is greater than the critical angle of incidence of described photon, namely then judge that described photon occurs be totally reflected and arrive detector, then will arrive the total number of light photons N of detector _totaladd 1, i.e. N _total=N _total+ 1; Wherein set N _totalinitial value be 0; P=1,2 ..., P.

5. the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation according to claim 1, it is characterized in that: in step (7), according to the reflection angle of each described photon on camera lens inside surface that step (6) calculates, calculate the component velocity that each photon is propagated in the radial and axial directions; Then according to the Z coordinate figure of axial component velocity, focal length and photon, the flight time that each described photon arrives detector focal plane is calculated; Calculate each photon that total reflection occurs according to the equation of motion again and arrive the coordinate figure behind detector focal plane; Concrete computation process is as follows:

(7a), calculate the component velocity of x-ray photon along optical axis direction and radial direction, specific formula for calculation is as follows:

V _q,1＝V ₀*cos(α _q)；

V _q,2＝V ₀*sin(α _q)；

Wherein, V _{q, 1}be q the component velocity of x-ray photon along optical axis direction that total reflection occurs, V _{q, 2}be q the x-ray photon component velocity radially that total reflection occurs, V ₀for the light velocity of setting; Wherein, q=1,2 ..., N _total;

(7b), the flight time that each x-ray photon that total reflection occurs arrives detector focal plane is calculated:

$T_q=\frac{f-z_q^{\′}}{V_{q,1}};$

Wherein, T _qbe q the flight time that the x-ray photon arrival detector focal plane of total reflection occurs, f is the optical system focal length of setting; z _q' be q occur total reflection x-ray photon original incident time Z coordinate; Wherein, q=1,2 ..., N _total;

(7c), calculate each occur total reflection x-ray photon arrive detector focal plane time position coordinates, specific formula for calculation is as follows:

${\hat{x}}_q={x_q}^{\′}-V_{q,2}\×T_q;$

${\hat{y}}_q={y_q}^{\′}-V_{q,2}\×T_q;;$

Wherein, be respectively the X-coordinate behind q the x-ray photon arrival detector focal plane occurring to be totally reflected and Y-coordinate; x _q' and y _q' be respectively q occur total reflection x-ray photon original incident time X-coordinate and Y-coordinate; Wherein, q=1,2 ..., N _total.

6. the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation according to claim 1, is characterized in that: according to the photon number N that total reflection occurs _totaland the ratio calculation between the x-ray photon sample size P of setting obtains 100% encircled energy of x-ray photon

7. the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation according to claim 1, it is characterized in that: calculate the X-coordinate behind the x-ray photon arrival detector focal plane that total reflection occurs and Y-coordinate in step (7) after, with detector center for the center of circle, and with for radius determines a circle on detector focal plane, add up the photon number entered in described circle namely described in position after individual x-ray photon arrives detector focal plane and the distance between detector center are less than or equal to

8. the grazing incidence optics system focusing performance analytical approach based on X ray optical simulation according to claim 7, is characterized in that: be less than or equal to according to the distance between the position behind arrival detector focal plane and detector center photon number and the ratio between the x-ray photon sample size P of setting, calculates 50% encircled energy of x-ray photon