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2022-02-25 09:52 |
Arizona眼睛模型
简介 Ml+f3#HP F%{z EANm 人眼光学模型可用来设计眼科用设备,光学系统注定了要与人眼一起使用。本文演示了这样一个模型:Arizona眼睛模型,在Jim Schwiegerling教授的书中有详细描述:《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源,并包括一个基于想要的屈光度来调整模型的内嵌脚本。 *0'{n*> y4!fu<[i 模型 +l7Bu} _? g K dNgU 模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 Gt !Hm( Table 1. AZ眼睛模型的定义 [attachment=111140] lb"T'}q A?)(^ 在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. }JT&lyO< b ~IQjQz? 光源 f\~w!- +ZBj_Vw*| 多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 v57Kr , /T6Te<68^ [attachment=111141] 图1. 光源和提示信息使用 5pRVA `0{qfms 除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 )S_%Ip W`n_m&Y\ 在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 \D[~54 [attachment=111142] 图2. 字母F光源的设定方法光 z:{R4#(Q 91#n Aj% [attachment=111143] 图3. 字母F在视网膜上位置点列图 2Paw*"U 1fF\k#BE-% 视网膜的散射 SC2g5i` ab 6D & 在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 2b:I. _b=})** [attachment=111144] 图4. 视网膜朗伯散射设定 .3
^*_ >rh<%55P` 注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 2Ju,P_<dt #P1;*m [attachment=111145] 图5. 视网膜重点采样规格设定 (fO~nN{F \l 3M\$oS> 脚本 3v<9 Z9O qv/chD`C 内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: [@s5v [attachment=111146] 图6. 用户对话框的创建与编辑 WS$~o*Z8 [attachment=111147] 图7. 用户对话框编辑器 -ktYS(8& e}L(tXZ 如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 HMR!XF&JjC 余下的脚本计算与屈光度有关的所有参数。 @jD19= q{)Q ?E 分析 v/wR)9 ,k/<Nv; 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 ] m^ECA$ [attachment=111148] 图7. 字母F在视网膜上颜色分析 ]JI
A\|b6 jbTyM"Y 脚本代码 z7lbb*Xe aK9zw
- Option Explicit 'Remove this to enable non-dimensioned variables to be used. VU|Cct&)
k${F7I(Tb Dim entity As T_ENTITY %M05& < Dim op As T_OPERATION N{zou?+ Dim mat As T_MODELMATERIAL Aj=c,]2 Dim A As Double /M_kJe,% Dim pupilDiam As Double C6b(\#g( Dim eID As Long f P1fm Dim parID As Long {*4Z9.2c* Dim count As Integer RjX#pb Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double dtq]_HvTJ Dim tlens As Double, nlens As Double T}A{Xu*:+H Dim curv As Double, conic As Double ;4]l P Dim ok As Long eYRm:KC ^kj%Ekt7 Sub Main 885
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'用户输入对话框 N&lKo}hk Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 p&;,$KDA TextBox 220,21,40,21,.TextBox1 'default: 0 h'G8@j; Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 q0
8 OKButton 40,91,90,21 SkA"MhX CancelButton 190,91,90,21 fBt7#Tc=U Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 GpM_Qp TextBox 220,49,40,21,.TextBox2 'default: 4 Tk4"qGC. End Dialog zX/9^+p: Dim dlg As UserDialog ]dIr;x` 6T~xjAuJ3T ok = Dialog (dlg) o>Z+=&BZ@a .](s\6' If ok=0 Then 'cancel button was pressed ^zaN?0%S33 Print "Execution cancelled." bpeWK& End _26F[R1><~ End If U
z6XQskX E^.
=^bR 'Assign accommodation and pupil diameter & use defaults if field left empty GQ9g $&T If dlg.TextBox1 = "" Then U=bZy,FT$ A = 0 'Default accommodation l=JK+uZ Else (wIpq<% A = CDbl(dlg.TextBox1) [VP~~*b End If ffYiu4$m NASRr If dlg.TextBox2 = "" Then #65Uei|F`+ pupilDiam = 4 'Default pupil diameter mWM!6" Else 5 ERycC y pupilDiam = CDbl(dlg.TextBox2) 0qV!-i End If +<H)DPG< QRv2%^L Print " "
`#lNur\x Print "Accommodation = " & A & " Diopters" 4<&`\<jZ Print "Pupil Diameter = " & pupilDiam & " mm" :
LI*#~'Ka vH#^ |u ' Calculate new parameters with accommodation s0"1W"7vh taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness ?o9g5Z p`JD8c Rant = 12.0 - 0.4*A 'Radius of anterior lens VscEdtkd CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens ,#r>#fi0 m.p{+_@M& Rpost = -5.224557 + 0.2*A 'Radius of posterior lens 5A6d] CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens OPwj*b:-m 5!G}*u. tlens = 3.767 + 0.04*A 'Lens thickness x*[\$E`v @vaK-&|#$ nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction "tbKKh66 e? fFh,a 'Adjust parameters to account for accommodation eJ#q! < GV([gs '************************************************************************* Dw^d!%Ala 'Aqueous thickness (Position of Lens) :WTO*M '************************************************************************* iVt6rX eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 1G+42>?<1 GetCustomElement eID, entity ,m:YZ;J(Xd MDS;qZx= parID = FindFullName( "Geometry.Arizona Eye" ) Kuy,qZv!" =?3D:k7z ' Delete any shift(s) in z yla&/K;|* count = 0 8hi|F\$_h While GetOperationCount(eID)>count g#1_`gK GetOperation eID, count, op (AdQ6eGM b If op.Type="ShiftZ" Then kQ~*iY DeleteOperation eID,count `Q*L!/K+ count=count-1 ".eD&oX{ End If ,.uPlnB_ count=count+1 V 3-5:z Wend /4]M*ls : \w\K: 'Set new shift in 'tp1|n/1 op.Type = "ShiftZ" :0j9 op.val1 = taq 9Ay*' op.parent = parID ayuj)]b AddOperation eID, op `Xnu("w) Print "Set aqueous humor thickness = " & taq-0.55 )G0a72 n97A'"'wz '************************************************************************* C w`v\
9 'Radius and conic constant of anterior lens -U(T '************************************************************************* &CFHH"OsT eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) }r6SV%]: GetConic eID, entity, curv, conic %^g BDlR^ }N1Z7G SetConic eID, entity, 1/Rant, CCant INsc!xOQ Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant }.O2xZ;}]' ";cWK29\f '************************************************************************* [Zk|s9 'Radius and conic constant of posterior lens !L+*.k: '************************************************************************* 2![.Kbqa% eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) )%U&z>^P GetConic eID, entity, curv, conic AxUj CerNf Aq}]{gfQ1 SetConic eID, entity, 1/Rpost, CCpost %<JjftNQ Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 67Z|=B!7 ;$=`BI) '************************************************************************* EUU9JnQhBJ 'Lens thickness (Position of posterior lens surface) ._"U{
f2V '************************************************************************* TGGeTtk= [J0L7p*6 parID = FindFullName( "Geometry.Arizona Eye.Lens" ) LZV K>9]I97g' ' Delete any z-shift(s) k`6T% [D] count = 0 ^$DpdzI While GetOperationCount(eID)>count l)fF)\ |;= GetOperation eID, count, op ^_r8R__S: If op.Type="ShiftZ" Then dy;Ue5 DeleteOperation eID,count b&B<'Wb count=count-1 z@^l1)m End If cOthq87: count=count+1 i=@.u=: Wend &96I4su ZkkXITQkPM 'Set new z-shift sXkWs2! op.Type = "ShiftZ" mF[w-<:.d op.val1 = tlens z,[4BM op.parent = parID gR"'|c AddOperation eID, op J{Ei+@^/9 Print "Set lens thickness = " & tlens s={AdQ /cUcfe#X '************************************************************************* (Sr&Y1D 'Lens index of refraction qi_[@da f? '************************************************************************* ~xpU<Pd* eID = FindMaterial( "Lens" ) 8P0XY
S@ GetModelMaterial eID, mat *r$Yv&c, wIz<Y{HA= mat.Nd = nlens Z!60n{T79c SetModelMaterial eID, mat snOd
3Bw Print "Set lens index of refraction = " & nlens k:Sxs+)?1 K?,eIZ{.S '************************************************************************* NduvfA4 'Pupil diameter sH(4.36+ '************************************************************************* |\%[e@u eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) B1oi]hDy iXK.QktHw 'Adjust pupil diameter (trimming volume inner hole) T>e!DOW; PuqT&|wP l SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" o {Sc 1w/1k6`0 ' Adjust pupil location to just in front of the lens N%%2!Z# parID = FindFullName( "Geometry.Arizona Eye" ) ?Ko)AP eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) S)of.Nq.; count = 0 d76k1-m\o While GetOperationCount(eID)>count Ol6jx%Je` GetOperation eID, count, op H%>
E6rVB If op.Type="ShiftZ" Then M.))UKSF DeleteOperation eID,count ^&buX_nlO count=count-1 %>Z^BM<e End If Ikql count=count+1 im|(
4f Wend M?Tb9c?` op.Type = "ShiftZ" 0m7ANqE[Z op.val1 = taq-0.01 &[$qA op.parent = parID 2W:R{dHE AddOperation eID, op kg?[
x7)j?2 Print "Set pupil diameter = " & pupilDiam 2jV.\C k A!\ouKyayS 'Update AZ Eye subassembly Description q`_d>l eID = FindFullName( "Geometry.Arizona Eye" ) L|.q19b* GetEntity eID, entity A(G%9'T entity.Description = "Accommodation = " & A & "D"
?TA%P6Lw SetEntity eID, entity 9J h"1i>x2 UjxEbk5>^ Update A&X(\ c M Print "DONE!" 8\HL8^6c5 VI7f} End Sub H6%QM}t 'QW/TJ=7r 如果屈光度是4,光瞳直径是4,则会输出如下数据: IV*@}~BJ (T:OZmEO. Accommodation = 4 Diopters `!WtKqr%B Pupil Diameter = 4 mm P,U$
X+ Set aqueous humor thickness = 2.81 BH6)`0&2*N Set anterior lens radius = 10.4 and conic constant = -2.375869 |&OW_*l Set posterior lens radius = -4.424557 and conic constant = -3.081019 2u9O+]EP Set lens thickness = 3.927 7Mq4$|qhD Set lens index of refraction = 1.42672 &J(+XJM% Set pupil diameter = 4 XCr\Y`,Z@ DONE!
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