CN102419205A - Light path capable of compressing light spots and improving resolution simultaneously - Google Patents

Abstract

The invention relates to a light path capable of compressing light spots and improving resolution simultaneously, belonging to the field of spectrographs. The light path is characterized by comprising a sample light path and a chromatic dispersion light path, wherein the sample light path successively comprises a light source 1, a first plane mirror 21, a first reflector 31, a sample chamber 4, a second reflector 32, a second plane mirror 22 and a slit 5, the chromatic dispersion light path successively comprises a third reflector 33, an optical grating 6, a fourth reflector 34 and a detector 7, and in each reflector, a toroid mirror is adopted for compressing light spots. By adoption of a triple cosine formula, a relation among an off-axis angle of a principal ray to the third reflector used as a collimation objective lens, an off-axis angle of the principal ray to the fourth reflector used as an imaging objective lens, an incidence angle and a diffraction angle of the principal ray to an optical grating, and the curvature radiuses of the third reflector and the fourth reflector in a meridian direction is established by the chromatic dispersion light path so as to reduce aberration, and a select range of each parameter is proposed independently. According to the invention, the light spots are compressed and the resolution of the light path is increased simultaneously.

Description

A kind of light path that can compress hot spot simultaneously and improve resolution

Technical field

The present invention relates to that a kind of employing new type reflection mirror---the light path of toroidal mirror can be applied to the spectral instrument field.

Background technology

The efficiency of light energy utilization and resolution are to estimate two important indicators of spectrometric instrument performance, yet there is certain contradiction property in both.The spectral instrument optical module mainly is divided into two pith modules---and sample light path module and chromatic dispersion light path module, the image quality of improving these two modules are to improve the key of spectrometric instrument performance.

Jap.P. JP2003014631A discloses a kind of scheme of improving spectral instrument sample light path, and shown in accompanying drawing 1, its sample light path part is mainly by light source 1,2; Semi-transparent semi-reflecting lens 3, toroidal mirror 4, plane mirror 5; Atomization portion 8, spherical reflector 9, plane mirror 10 is formed; The light that light source sends focuses on through toroidal mirror 4; Converge to atomization portion 8 through plane mirror 5 turnover again, the physicochemical characteristic of sample is converted into optical characteristics, focus on through spherical reflector 9 and form pointolite and in follow-up chromatic dispersion light path, carry out spectral analysis.Toroidal mirror is commonly called as the tire mirror, is a kind of catoptron, and it has two radius-of-curvature on the mutual vertical direction.This patent adopts toroidal mirror 4 in the sample light path, advantage is the optical quality that can improve in the atomization portion 8, and the compression hot spot is to improve the efficiency of light energy utilization of subsequent optical path.The defective of this patent is the resolution that this sample light path can not be improved whole light path, and does not explain how design parameter is put toroidal mirror.Still have can improved place for this patent sample light path part simultaneously, can substitute with further compression hot spot with toroidal mirror such as spherical reflector 9, improves the efficiency of light energy utilization.

U.S. Pat 5192981A has proposed a kind of scheme of improving spectrometer Qie Erni-Tener chromatic dispersion light path; Shown in accompanying drawing 2, this chromatic dispersion light path adopts Qie Erni-Tener structure, mainly is made up of entrance slit 18, collimator objective 40, grating 52, image-forming objective lens 80, exit slit 20; Light gets into structure from entrance slit 18; Be collimated into directional light through collimator objective 40,52 beam split are incident to image-forming objective lens 80 through grating, in exit slit 20 places outgoing.This patent uses toroidal mirror as collimator objective 40, and advantage is to compress hot spot, improves the efficiency of light energy utilization of whole light path.The defective of this patent is effectively to improve the resolution of chromatic dispersion light path, does not explain equally how design parameter is put toroidal mirror.Still have can improvements for this chromatic dispersion light path simultaneously, also can adopt toroidal mirror with further compression hot spot such as image-forming objective lens 80, improve the efficiency of light energy utilization.

Arthur B.Shafer has mentioned the method for a kind of Qie Erni of improvement-Tener light path resolution in its paper " Optimization of the Czerny-Turner Spectrometer ", promptly utilize cos ³Formula

$\frac{\sin \mathrm{\&beta;}}{\sin \mathrm{\&alpha;}}=\frac{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">R</figure-callout>}}_2^2{\mathrm{<figure-callout\; id="3"\; label="cos"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^3\mathrm{\&beta;}{\cos }^{3}i}{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA0000083761770000072.png"\; state="\{\{state\}\}">R</figure-callout>}}_1^2{\mathrm{<figure-callout\; id="3"\; label="cos"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^3\mathrm{\&alpha;}{\mathrm{<figure-callout\; id="3"\; label="cos"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^3\mathrm{\&theta;}}$

Calculate chief ray collimation object lens off-axis angle α and image-forming objective lens off-axis angle β and chief ray to the incident angle i of grating and the relation of diffraction angle, shown in accompanying drawing 3, R ₁And R ₂It is respectively the radius-of-curvature of collimator objective and image-forming objective lens in the chromatic dispersion light path; α and β are respectively the off-axis angles of chief ray collimation object lens and image-forming objective lens; I and θ are respectively incident angle and the angle of diffraction of chief ray to grating; Wherein chief ray is meant the main design light of single wavelength, and off-axis angle is meant the angle of incident ray or emergent ray and mirror optical axis.Can reduce the coma in the chromatic dispersion light path effectively according to this formulae design parameter, thereby improve the resolution of light path.The defective of this method is will shorten hot spot into elongate, and shown in accompanying drawing 8.1, this can make detector can not detect whole hot spots, causes the waste of luminous energy.

Summary of the invention

The technical matters that the present invention will solve provide a kind of simple in structure, cost is low, good manufacturability, improve the light path of the resolution and the efficiency of light energy utilization simultaneously.

The characteristic that the present invention can improve the light path of the resolution and the efficiency of light energy utilization simultaneously is to contain sample light path and chromatic dispersion light path, wherein:

The sample light path contains light source 1, the first plane mirror 21, the first catoptrons 31, sample chamber 4, the second catoptrons, 32, the second plane mirrors 22 and slit 5, wherein:

First plane mirror 21 receives incident light that said light source 1 sends and to the 31 reflection outputs of said first catoptron,

First catoptron 31 receives the output light of said first plane mirror 21 and reflects output to said sample chamber 4,

Sample chamber 4, the output light that receives said first catoptron 31 also incides on said second catoptron 32 seeing through the light beam that obtains behind the sample,

Second catoptron 32 receives the output light of said sample chamber 4 and reflects output to said second plane mirror 22,

Second plane mirror 22 receives the output light of said second catoptron 32 and reflects output to slit 5;

The chromatic dispersion light path contains makes the 3rd catoptron 33 that the collimation object lens are used, and grating 6 is made the 4th catoptron 34 and detector 7 that the imaging object lens are used, wherein:

The 3rd catoptron 33 receives the output light of said slit 5 and reflects output to said grating 6,

Grating 6 receives the output light of said the 3rd catoptron 33 and to the output of said the 4th catoptron 34 diffraction,

The 4th catoptron 34 receives the output light of said grating 6 and reflects output to said detector 7, wherein:

Described four catoptrons 31,32,33,34 all adopt toroidal mirror, and toroidal mirror is at the radius-of-curvature ρ of sagitta of arc direction ₃Calculate by following formula

ρ ₃＝R ₃cos ²α ₃，

R wherein ₃Be the radius-of-curvature of toroidal mirror at meridian direction, α ₃For wavelength is the off-axis angle of the chief ray of 190nm to toroidal mirror;

In described chromatic dispersion light path, the radius of curvature R of said collimator objective 33 meridian directions ₃₃, image-forming objective lens 34 meridian directions radius of curvature R ₃₄, wavelength is the off-axis angle α of the chief ray of 190nm to said collimator objective 33 ₃₃, wavelength is the off-axis angle α of the chief ray of 190nm to said image-forming objective lens 34 ₃₄, wavelength is that the chief ray of 190nm should satisfy following relational expression to the incident angle i and the diffraction angle of said grating 6

$\frac{\sin {\mathrm{\&alpha;}}_{34}}{\sin {\mathrm{\&alpha;}}_{33}}=\frac{R_{34}^2{\mathrm{<figure-callout\; id="3"\; label="cos"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^3{\mathrm{\&alpha;}}_{34}{\cos }^{3}i}{R_{33}^2{\mathrm{<figure-callout\; id="3"\; label="cos"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^3{\mathrm{\&alpha;}}_{33}{\mathrm{<figure-callout\; id="3"\; label="cos"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^3\mathrm{\&theta;}};$

Said each angle α ₃₁, α ₃₂, α ₃₃, α ₃₄, i, θ and each meridian direction radius of curvature R ₃₁, R ₃₂, R ₃₃, R ₃₄Span be respectively

α ₃₁＝14.3°～14.7°，

α ₃₂＝10.8°～11.1°，

α ₃₃＝5.9°～6.3°，

α ₃₄＝7.5°～8.1°，

i＝3.8877°，

θ＝24.1923°，

R ₃₁＝250.7mm～251.1mm，

R ₃₂＝215.9mm～216.2mm，

R ₃₃＝600mm，

R ₃₄＝600mm。

Describedly a kind ofly can compress hot spot simultaneously and improve in the light path of resolution, said second catoptron 32 or the 3rd catoptron 33 or the 4th catoptron 34 can replace with spherical mirror.

The picture of meridian direction can coincide together with the picture of sagitta of arc direction effectively behind the toroidal mirror; Thereby reduce the influence of astigmatism, so toroidal mirror can compress hot spot and improve picture element, can observe this phenomenon through experiment; Shown in accompanying drawing 7; The image patch disperse of spherical reflector is very big, and the image patch of toroidal mirror does not almost have disperse, and picture element is fine; Utilize cos ³The major parameter of formulae design chromatic dispersion light path can reduce the coma of chromatic dispersion light path effectively, improves the resolution of system.The comprehensive above method of the present invention; And the span of main design parameters proposed independently; So can simple in structure, cost is low, improve the spectrometric instrument efficiency of light energy utilization and resolution simultaneously on the manufacturability good basis, thereby improve the performance of spectrometric instrument.

Description of drawings

Fig. 1 is Jap.P. JP2003014631A light channel structure figure.

Fig. 2 is U.S. Pat 5192981A constructional device figure.

Fig. 3 is the angle synoptic diagram of Qie Erni in the ArthurB.Shafer paper-Tener chromatic dispersion light path.

Fig. 4 is a light path illustraton of model of the present invention.

Fig. 5 is the radius-of-curvature and the off-axis angle synoptic diagram of toroidal mirror.

Fig. 6 is that toroidal mirror substitutes Experimental equipment.

Fig. 7 is the CCD of the light place of the converging CCD of the light place of the converging Fig. 7 .2 that takes pictures that takes pictures behind Fig. 7 .1 and the toroidal mirror behind the spherical reflector.

Fig. 8 is the zemax emulation image quality analysis of embodiment one light path M1M2M3M4, and wherein Fig. 8 .1 is the geometric image analysis, and Fig. 8 .2 is the RMS radius distance value.

Fig. 9 is the zemax emulation image quality analysis of embodiment one light path M1 ' M2M3M4, and wherein Fig. 9 .1 is the geometric image analysis, and Fig. 9 .2 is the RMS radius distance value.

Figure 10 is the zemax emulation image quality analysis of embodiment two light path M1 ' M2M3 ' M4, and wherein Figure 10 .1 is the geometric image analysis, and Figure 10 .2 is the RMS radius distance value.

Figure 11 is the zemax emulation image quality analysis of embodiment three light path M1 ' M2M3M4 ', and wherein Figure 11 .1 is the geometric image analysis, and Figure 11 .2 is the RMS radius distance value.

Figure 12 is the zemax emulation image quality analysis of embodiment four light path M1 ' M2M3 ' M4 ', and wherein Figure 12 .1 is the geometric image analysis, and Figure 12 .2 is the RMS radius distance value.

Figure 13 is the zemax emulation image quality analysis of embodiment five light path M1 ' M2 ' M3M4, and wherein Figure 13 .1 is the geometric image analysis, and Figure 13 .2 is the RMS radius distance value.

Figure 14 is the zemax emulation image quality analysis of embodiment six light path M1 ' M2 ' M3 ' M4, and wherein Figure 14 .1 is the geometric image analysis, and Figure 14 .2 is the RMS radius distance value.

Figure 15 is the zemax emulation image quality analysis of embodiment seven light path M1 ' M2 ' M3M4 ', and wherein Figure 15 .1 is the geometric image analysis, and Figure 15 .2 is the RMS radius distance value.

Figure 16 is the zemax emulation image quality analysis of embodiment eight light path M1 ' M2 ' M3 ' M4 ', and wherein Figure 16 .1 is the geometric image analysis, and Figure 16 .2 is the RMS radius distance value.

Embodiment

Light path provided by the invention; Shown in accompanying drawing 4; Form by light source 1, plane mirror 21, toroidal mirror 31, sample chamber 4, toroidal mirror 32, plane mirror 22, slit 5, toroidal mirror 33, grating 6, toroidal mirror 34 and detector 7, wherein the off-axis angle ρ of toroidal mirror ₃Satisfy formula

ρ ₃＝R ₃cos ²α ₃，

Shown in accompanying drawing 5, ρ ₃Be the radius-of-curvature of toroidal mirror in sagitta of arc direction, R ₃Be the radius-of-curvature of toroidal mirror at meridian direction, α ₃Be the off-axis angle of chief ray to toroidal mirror.The off-axis angle of each object lens of chromatic dispersion light path part is according to cos ³Formula

$\frac{\sin {\mathrm{\&alpha;}}_{34}}{\sin {\mathrm{\&alpha;}}_{33}}=\frac{R_{34}^2{\mathrm{<figure-callout\; id="3"\; label="cos"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^3{\mathrm{\&alpha;}}_{34}{\cos }^{3}i}{R_{33}^2{\mathrm{<figure-callout\; id="3"\; label="cos"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^3{\mathrm{\&alpha;}}_{33}{\mathrm{<figure-callout\; id="3"\; label="cos"\; filenames="HDA0000083761770000011.png"\; state="\{\{state\}\}">cos</figure-callout>}}^3\mathrm{\&theta;}}$

Calculate R ₃₃And R ₃₄Be respectively the meridian direction radius-of-curvature of collimator objective and image-forming objective lens in the chromatic dispersion light path, α ₃₃And α ₃₄Be respectively the off-axis angle of chief ray collimation object lens and image-forming objective lens, i and θ are respectively incident angle and the angle of diffraction of chief ray to grating.

In the said light path, said second catoptron 32 or the 3rd catoptron 33 or the 4th catoptron 34 can replace with spherical mirror.

The purpose that adopts plane mirror in the said light path is in order to make the light channel structure compactness keep the surplus of mechanical parts simultaneously, does not adopt plane mirror 21 or 22 and directly with spherical reflector or toroidal mirror a kind of scheme that also can't say that it is wrong.Also can increase the quantity of plane mirror or the position of change plane mirror according to structural requirement, because of needs are decided.

The light place of converging surveys and takes pictures after adopting identical ccd detector to spherical reflector and toroidal mirror, and experimental provision is shown in accompanying drawing 6, and wherein 1 is light source, and 2 is plane mirror, and 3 is spherical reflector or toroidal mirror, and 7 is ccd detector.Each distance is identical with parameters such as angles in the experiment; Toroidal mirror meridian direction radius-of-curvature is identical with curvature radius of spherical reflector; The result that takes pictures is shown in accompanying drawing 7, and wherein spot diameter is 4.5mm among Fig. 7 .1, and spot diameter is 2.4mm among Fig. 7 .2; As can be seen from the figure spherical reflector can produce bigger astigmatism and cause the hot spot disperse, makes that hot spot is very little and toroidal mirror has reduced the influence of astigmatism effectively.Therefore use the toroidal mirror can hot spot is more concentrated, uses small-sized detector can detect more light, thus the efficiency of light energy utilization of raising system.

Compare through eight embodiment at present.Wherein design the chief ray wavelength and be 190nm, slit is the rectangular slot of 8*0.04mm, and incident light numerical aperture NA is 0.06.

Embodiment one:

The light path M1M2M3M4 that at first to design a chromatic dispersion light path be symmetrical structure, M1, M2, M3, M4 corresponding catoptron 31,32,33,34 respectively wherein, subsequent implementation example expression mode is identical.This structure does not adopt toroidal mirror, does not utilize cos simultaneously yet ³Formula calculates off-axis angle, and parameter is as shown in table 1, and structural representation is shown in accompanying drawing 4.

Secondly according to the inventive method design light path M1 ' M2M3M4, wherein band ' represent that this catoptron adopts toroidal mirror, is not with ' represent that this catoptron adopts spherical mirror, subsequent implementation example expression mode is identical.Structural representation is shown in accompanying drawing 4, and wherein first catoptron 31 adopts toroidal mirrors, and second catoptron 32, the 3rd catoptron 33 and the 4th catoptron 34 adopt spherical mirrors, and design parameter is as shown in table 1, for toroidal mirror, and R ₃Represent its meridian direction radius-of-curvature, ρ ₃Represent its sagitta of arc directional curvature radius, the listed radius-of-curvature that is the toroidal mirror meridian direction in the table, in this light path, the sagitta of arc directional curvature radius ρ of toroidal mirror 31 ₃₁Value is 235.26mm.

Design parameter is imported zemax carry out emulation, it is good to find on newly-designed light path M1 ' M2M3M4 is than original optical path M1M2M3M4 performance to the RMS radius through contrast spot size and Y, shown in accompanying drawing 8 and accompanying drawing 9.

Table 1 embodiment light path M1M2M3M4 and other light path main design parameters

Embodiment two:

Design light path M1 ' M2M3 ' M4, structural representation are shown in accompanying drawing 4, and wherein first catoptron 31 and the 3rd catoptron 33 adopt toroidal mirror; Second catoptron 32 and the 4th catoptron 34 adopt spherical mirror, and design parameter is as shown in table 1, and present embodiment and subsequent implementation example main design parameters are identical with the main design parameters of light path M1 ' M2M3M4 among the embodiment; Only be different from the number and the position of toroidal mirror; Therefore list in same list item, after this repeat no more the ρ of toroidal mirror 31 in this example ₃₁Value is the ρ of 235.26mm, toroidal mirror 33 ₃₃Value is 593.22mm.Parameter can be obtained the picture element shown in 10 shown in accompanying drawing with zemax emulation.Contrast finds that resolution aspect (Y is to the RMS radius) is suitable with light path M1 ' M2M3M4, and image patch is compared with M1 ' M2M3M4 and compressed 14%.

Embodiment three:

Design light path M1 ' M2M3M4 '; Structural representation is shown in accompanying drawing 4, and wherein first catoptron 31 and the 4th catoptron 34 adopt toroidal mirror, and second catoptron 32 and the 3rd catoptron 33 adopt spherical mirror; Design parameter is as shown in table 1, the ρ of toroidal mirror 31 in this example ₃₁Value is the ρ of 235.26mm, toroidal mirror 34 ₃₄Value is 588.95mm.Parameter can be obtained the picture element shown in 11 shown in accompanying drawing with zemax emulation.Contrast finds that resolution aspect (Y is to the RMS radius) is suitable with light path M1 ' M2M3 ' M4, and image patch is compared with M1 ' M2M3 ' M4 and compressed 8%.

Embodiment four:

Design light path M1 ' M2M3 ' M4 '; Structural representation is shown in accompanying drawing 4, and wherein first catoptron 31, the 3rd catoptron 33 and the 4th catoptron 34 adopt toroidal mirrors, and second catoptron 32 adopts spherical mirrors; Design parameter is as shown in table 1, the ρ of toroidal mirror 31 in this example ₃₁Value is the ρ of 235.26mm, toroidal mirror 33 ₃₃Value is the ρ of 593.22mm, toroidal mirror 34 ₃₄Value is 588.95mm.Parameter can be obtained the picture element shown in 12 shown in accompanying drawing with zemax emulation.Contrast finds that resolution aspect (Y is to the RMS radius) and light path M1 ' M2M3M4 ' are suitable, and image patch is compared with M1 ' M2M3M4 ' and compressed 17%.

Embodiment five:

Design light path M1 ' M2 ' M3M4; Structural representation is shown in accompanying drawing 4, and wherein first catoptron 31 and second catoptron 32 adopt toroidal mirror, and the 3rd catoptron 33 and the 4th catoptron 34 adopt spherical mirror; Design parameter is as shown in table 1, the ρ of toroidal mirror 31 in this example ₃₁Value is the ρ of 235.26mm, toroidal mirror 32 ₃₂Value is 208.28mm.Parameter can be obtained the picture element shown in 13 shown in accompanying drawing with zemax emulation.Contrast finds that resolution aspect (Y is to the RMS radius) is compared with light path M1 ' M2M3 ' M4 ' and improved 7%, and image patch is compared with M1 ' M2M3 ' M4 ' and compressed 38%.

Embodiment six:

Design light path M1 ' M2 ' M3 ' M4; Structural representation is shown in accompanying drawing 4, and wherein first catoptron 31, second catoptron 32 and the 3rd catoptron 33 adopt toroidal mirrors, and the 4th catoptron 34 adopts spherical mirrors; Design parameter is as shown in table 1, the ρ of toroidal mirror 31 in this example ₃₁Value is the ρ of 235.26mm, toroidal mirror 32 ₃₂Value is the ρ of 208.28mm, toroidal mirror 33 ₃₃Value is 593.22mm.Parameter can be obtained the picture element shown in 14 shown in accompanying drawing with zemax emulation.Contrast finds that resolution aspect (Y is to the RMS radius) is suitable with light path M1 ' M2 ' M3M4, and image patch is compared with M1 ' M2 ' M3M4 and compressed 38%.

Embodiment seven:

Design light path M1 ' M2 ' M3M4 '; Structural representation is shown in accompanying drawing 4, and wherein first catoptron 31, second catoptron 32, the 4th catoptron 34 adopt toroidal mirrors, and the 3rd catoptron 33 adopts spherical mirrors; Design parameter is as shown in table 1, the ρ of toroidal mirror 31 in this example ₃₁Value is the ρ of 235.26mm, toroidal mirror 32 ₃₂Value is the ρ of 208.28mm, toroidal mirror 34 ₃₄Value is 588.95mm.Parameter can be obtained the picture element shown in 15 shown in accompanying drawing with zemax emulation.Contrast finds that resolution aspect (Y is to the RMS radius) is suitable with light path M1 ' M2 ' M3 ' M4, and image patch is compared with M1 ' M2 ' M3 ' M4 and compressed 30%.

Embodiment eight:

Design light path M1 ' M2 ' M3 ' M4 ', structural representation are shown in accompanying drawing 4, and wherein first catoptron 31, second catoptron 32, the 3rd catoptron 33 and the 4th catoptron 34 all adopt toroidal mirror, and design parameter is as shown in table 1, the ρ of toroidal mirror 31 in this example ₃₁Value is the ρ of 235.26mm, toroidal mirror 32 ₃₂Value is the ρ of 208.28mm, toroidal mirror 33 ₃₃Value is the ρ of 593.22mm, toroidal mirror 34 ₃₄Value is 588.95mm.Parameter can be obtained the picture element shown in 16 shown in accompanying drawing with zemax emulation.Contrast finds that resolution aspect (Y is to the RMS radius) and light path M1 ' M2 ' M3M4 ' are suitable, and image patch is compared with M1 ' M2 ' M3M4 ' and compressed 78%.

The identical 4mm that is of accompanying drawing 8～16 medium scales, image more novel Mingguang City congruence gather concentrated more, the efficiency of light energy utilization is high more.

Table 2 is depicted as the image size contrast of each embodiment; Can effectively compress hot spot in the time of from table, can finding out that second catoptron 32 is for toroidal mirror shown in the accompanying drawing 4; Compression effectiveness was not obvious when second catoptron 32 was spherical mirror; Along with the increase of toroidal mirror number, the effect of compression of images is become better and better simultaneously.In ensuing work, will carry out the contrast experiment of this part, obtain experimental data and verify that spherical mirror replaces with the feasibility of this scheme of toroidal mirror.

Table 3 is depicted as the RMS radius of light path (equivalence is resolution) contrast in two light paths and embodiment five among the embodiment one, and wherein the bright resolution of novel is high more more for the RMS radius.From table, can find to adopt cos ³Formula can improve the resolution of whole light path effectively, and second catoptron 32 is not the resolution height of the light path of toroidal mirror for the light path of toroidal mirror than it simultaneously, and this explanation toroidal mirror also has the effect that improves resolution.Little when the 3rd catoptron 33 and the 4th catoptron 34 are toroidal mirror or spherical mirror for the influence of resolution, do not give unnecessary details at this.

The contrast of accompanying drawing 8～16 and table 2～3 can find that the number that replaces to toroidal mirror along with spherical mirror increases, and the picture element that emulation obtains improves gradually.And optimum light path of the present invention can be with the hot spot compression 98% of original optical path, and resolution improves 26% simultaneously, and the contradiction property that the invention solves between the resolution and the efficiency of light energy utilization can be described.

Table 4 is depicted as zemax emulation obtains under the edge parameters value of light path major parameter range of choice among the embodiment eight image size and Y, and big or small and Y contrasts to the value of RMS radius with the image among the embodiment eight to the value of RMS radius (equivalence is resolution); Wherein when getting a certain edge parameters, other parameters all drop in the said parameter range of choice.From table, can see that the value of edge parameters has a little influence for picture element, but DeGrain, therefore light path is functional in described parameter range of choice.

Each embodiment light path zemax emulating image size contrast of table 2

The light path title	Emulating image size (mm)	Improve number percent in preceding light path
			M1M2M3M4	5.49
M1’M2M3M4	2.91	46.99％
			M1’M2M3’M4	2.50	14.09％
M1’M2M3M4’	2.29	8.40％
			M1’M2M3’M4’	1.89	17.47％
M1’M2’M3M4	1.16	38.62％
			M1’M2’M3’M4	0.72	37.93％
M1’M2’M3M4’	0.50	30.56％
			M1’M2’M3’M4’	0.11	78.00％

Table 3 embodiment light path zemax emulation Y contrasts to the RMS radii size

The light path title	Y is to RMS radii size (μ m)	Improve number percent in original optical path
			M1M2M3M4	11.87
M1’M2M3M4	9.38	20.98％
			M1’M2’M3M4	8.74	26.37％

The picture element of table 4 embodiment eight light path edge parameters values and zemax emulating image

Claims (8)

1. the light path that can compress hot spot simultaneously and improve resolution is characterized in that, contains sample light path and chromatic dispersion light path, wherein:

The sample light path contains light source (1), first plane mirror (21), and first catoptron (31), sample chamber (4), and second catoptron (32), second plane mirror (22) and slit (5), wherein:

First plane mirror (21) receives incident light that said light source (1) sends and to said first catoptron (31) reflection output,

First catoptron (31) receives the output light of said first plane mirror (21) and reflects output to said sample chamber (4),

Sample chamber (4), the output light that receives said first catoptron (31) also incides on said second catoptron (32) seeing through the light beam that obtains behind the sample,

Second catoptron (32) receives the output light of said sample chamber (4) and reflects output to said second plane mirror (22),

Second plane mirror (22) receives the output light of said second catoptron (32) and reflects output to slit (5);

The chromatic dispersion light path contains makes the 3rd catoptron (33) that the collimation object lens are used, and grating (6) is made the 4th catoptron (34) and detector (7) that the imaging object lens are used, wherein:

The 3rd catoptron (33) receives the output light of said slit (5) and reflects output to said grating (6),

Grating (6) receives the output light of said the 3rd catoptron (33) and to said the 4th catoptron (34) diffraction output,

The 4th catoptron (34) receives the output light of said grating (6) and reflects output to said detector (7), wherein:

Described four catoptrons (31,32,33,34) all adopt toroidal mirror, and toroidal mirror is at the radius-of-curvature ρ of sagitta of arc direction ₃Calculate by following formula

ρ ₃＝R ₃cos ²α ₃，

R wherein ₃Be the radius-of-curvature of toroidal mirror at meridian direction, α ₃For wavelength is the off-axis angle of the chief ray of 190nm to toroidal mirror;

In described chromatic dispersion light path, the radius of curvature R of said collimator objective (33) meridian direction ₃₃, image-forming objective lens (34) meridian direction radius of curvature R ₃₄, wavelength is the off-axis angle α of the chief ray of 190nm to said collimator objective (33) ₃₃, wavelength is the off-axis angle α of the chief ray of 190nm to said image-forming objective lens (34) ₃₄, wavelength is that the chief ray of 190nm should satisfy following relational expression to the incident angle i and the diffraction angle of said grating (6)

$\frac{\sin {\mathrm{\&alpha;}}_{34}}{\sin {\mathrm{\&alpha;}}_{33}}=\frac{R_{34}^2{\cos }^3{\mathrm{\&alpha;}}_{34}{\cos }^{3}i}{R_{33}^2{\cos }^3{\mathrm{\&alpha;}}_{33}{\cos }^3\mathrm{\&theta;}};$

Said each angle α ₃₁, α ₃₂, α ₃₃, α ₃₄, i, θ and each meridian direction radius of curvature R ₃₁, R ₃₂, R ₃₃, R ₃₄Span be respectively

α ₃₁＝14.3°～14.7°，

α ₃₂＝10.8°～11.1°，

α ₃₃＝5.9°～6.3°，

α ₃₄＝7.5°～8.1°，

i＝3.8877°，

θ＝24.1923°，

R ₃₁＝250.7mm～251.1mm，

R ₃₂＝215.9mm～216.2mm，

R ₃₃＝600mm，

R ₃₄＝600mm。

2. a kind of light path that can compress hot spot simultaneously and improve resolution according to claim 1 is characterized in that said the 3rd catoptron (33) replaces with spherical mirror.

3. a kind of light path that can compress hot spot simultaneously and improve resolution according to claim 1 is characterized in that said the 4th catoptron (34) replaces with spherical mirror.

4. a kind of light path that can compress hot spot simultaneously and improve resolution according to claim 1 is characterized in that said the 3rd catoptron (33) and the 4th catoptron (34) all replace with spherical mirror.

5. a kind of light path that can compress hot spot simultaneously and improve resolution according to claim 1 is characterized in that said second catoptron (32) replaces with spherical mirror.

6. a kind of light path that can compress hot spot simultaneously and improve resolution according to claim 1 is characterized in that said second catoptron (32) and the 3rd catoptron (33) all replace with spherical mirror.

7. a kind of light path that can compress hot spot simultaneously and improve resolution according to claim 1 is characterized in that said second catoptron (32) and the 4th catoptron (34) all replace with spherical mirror.

8. a kind of light path that can compress hot spot simultaneously and improve resolution according to claim 1 is characterized in that said second catoptron (32), the 3rd catoptron (33) and the 4th catoptron (34) all replace with spherical mirror.

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