[技术]Arizona眼睛模型 [复制链接]

简介 GmK^}=frj  
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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。 ,t3wp#E2#  
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模型 "RedK '7g  
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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。 -<6\1J  
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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. Ii6<b6-  
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光源 .b_)%jd x  
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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。 ky8_UnaO  
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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。 v/@^Q1G/:  
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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。 bw(a6qKK  
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视网膜的散射 S O4u9V  
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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。 Yf:IKY  
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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。 l~1Oef#y  
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脚本 {mm)ay|M  
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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： Gp1?iX?ml  
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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。 +"x,x  
余下的脚本计算与屈光度有关的所有参数。 G"klu  
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分析 W~6
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 kv]~'Srk  
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脚本代码 NYyh|X:m  

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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 1uG"f<TsR  
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Dim entity As T_ENTITY 83E7k]7]  
Dim op As T_OPERATION ht7l- AK  
Dim mat As T_MODELMATERIAL "/)#O
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Dim A As Double _|iSF2f,X  
Dim pupilDiam As Double V\t.3vT  
Dim eID As Long M:XSQ["6>V  
Dim parID As Long wE[]6\_x1  
Dim count As Integer N<|@ymi  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 1cx
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Dim tlens As Double, nlens As Double f) znTJL  
Dim curv As Double, conic As Double S-P/+K6  
Dim ok As Long U(a#@K!H  
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Sub Main PbW(%7o(t  
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    '用户输入对话框 %Da8{%{`Pc  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Z&#('Z  
        TextBox 220,21,40,21,.TextBox1 'default: 0 b$4"i XSQ  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 $g/S
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        OKButton 40,91,90,21 FR$:"  
        CancelButton 190,91,90,21 N2B|SO''  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 T~--92[  
        TextBox 220,49,40,21,.TextBox2 'default: 4 L\Aq6q@c  
    End Dialog Y?S!8-z  
    Dim dlg As UserDialog jB`,u|FG  
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    ok = Dialog (dlg) 5Ec6),+&  
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    If ok=0 Then    'cancel button was pressed 2#P*,  
        Print "Execution cancelled." LISMngQ.  
        End nKS7Q1+  
    End If b8~Bazk  
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    'Assign accommodation and pupil diameter & use defaults if field left empty |L-]fjBbF  
    If dlg.TextBox1 = "" Then Kw-gojZ  
        A = 0           'Default accommodation { WIJC',Y  
    Else %{ABaeb]  
        A = CDbl(dlg.TextBox1) *#E FsUw  
    End If Rd2qe /  
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    If dlg.TextBox2 = "" Then |y&*MTfV4L  
        pupilDiam = 4   'Default pupil diameter I`p+Qt  
    Else O]lSWEe  
        pupilDiam = CDbl(dlg.TextBox2) XaCX!Lr,  
    End If m=?KZ?U`  
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    Print " " {kp
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    Print "Accommodation = " & A & " Diopters" W"zab
 
    Print "Pupil Diameter = " & pupilDiam & " mm" Px$/ _`H  
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    ' Calculate new parameters with accommodation b@rVo;  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness M\sN@+  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens }vZ+A
 
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens !+1<E*NQ S  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens )\_:{c  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens X*M#F
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    tlens = 3.767 + 0.04*A                  'Lens thickness sp#p8@Cj  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 
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    'Adjust parameters to account for accommodation =4[v3Qx  
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    '************************************************************************* whpfJNz  
    'Aqueous thickness (Position of Lens) @W vatD V  
    '************************************************************************* hJn%mdx~w|  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) z8QAo\_I(  
    GetCustomElement eID, entity 1nQWW9i
 
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    parID = FindFullName( "Geometry.Arizona Eye" ) X*&[u7No  
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    ' Delete any shift(s) in z iMIlZ  
    count = 0 |UK}  
    While GetOperationCount(eID)>count [ JpKSTg[
 
        GetOperation eID, count, op LJ*q1 ;<E  
        If op.Type="ShiftZ" Then X}tVmO?  
            DeleteOperation eID,count {7$c8i  
            count=count-1 IIg^FZ*]_  
        End If O$IEn/%+  
        count=count+1 l%?T2Fm3>  
    Wend OlAs'TE^  
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    'Set new shift in ?**+e%$$  
    op.Type = "ShiftZ" ?*E'^~,H)  
    op.val1 = taq dE:+k/  
    op.parent = parID IqC]!H0  
    AddOperation eID, op %F!1  
    Print "Set aqueous humor thickness = " & taq-0.55 K@#(*."  
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    '************************************************************************* Fb^:V4<T  
    'Radius and conic constant of anterior lens V>ieh2G(  
    '************************************************************************* !OBEM1~ 1  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Ys@}3\Mc  
    GetConic eID, entity, curv, conic 30XR 82P/  
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    SetConic eID, entity, 1/Rant, CCant )^4\,
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    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant p$
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    '************************************************************************* /h*>P:i].  
    'Radius and conic constant of posterior lens 4T!+D  
    '************************************************************************* c8L~S/t  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Hz.(qW">5*  
    GetConic eID, entity, curv, conic Z7_m)@%;kk  
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    SetConic eID, entity, 1/Rpost, CCpost 89\n;5'f4  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost &K/ya7  

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    '************************************************************************* #;%JT   
    'Lens thickness (Position of posterior lens surface) '[C.|)"  
    '************************************************************************* UVw~8o9s  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Xb{ [c+.  
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    ' Delete any z-shift(s) 9T|IvQK8  
    count = 0 blTo5NLX  
    While GetOperationCount(eID)>count \RvvHty-V  
        GetOperation eID, count, op y($%;l   
        If op.Type="ShiftZ" Then 8"dv_`ym  
            DeleteOperation eID,count "\}@gV#r$A  
            count=count-1 SzUpWy&  
        End If 6`]$qSTS  
        count=count+1 epU:  
    Wend G8r``{C!  
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    'Set new z-shift (N&lHLy  
    op.Type = "ShiftZ" B>GE9y5  
    op.val1 = tlens ,Fi>p0bz  
    op.parent = parID o(S{VGi,  
    AddOperation eID, op yil[gPy4B  
    Print "Set lens thickness = " & tlens |1b
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    '************************************************************************* SQqD:{#g"  
    'Lens index of refraction
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    '************************************************************************* 6xZ=^;H  
    eID = FindMaterial( "Lens" ) 91$]Qg,lB  
    GetModelMaterial eID, mat :_t}QP"  
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    mat.Nd = nlens df n9!h  
    SetModelMaterial eID, mat R,|d`)T  
    Print "Set lens index of refraction = " & nlens ,4ei2`wV  
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    '************************************************************************* <o+<H  
    'Pupil diameter GKoK7qH\J  
    '************************************************************************* P&b19K'  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ]p;FZ4-T  
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    'Adjust pupil diameter (trimming volume inner hole) 'Er:a?88l  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 1qf!DMcdZ  
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    ' Adjust pupil location to just in front of the lens #/I[Jqf  
    parID = FindFullName( "Geometry.Arizona Eye" ) <<i3r|
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) PSPmO'C+  
    count = 0 h}]fnA  
    While GetOperationCount(eID)>count dw TMq*e  
        GetOperation eID, count, op Ay !G1;  
        If op.Type="ShiftZ" Then cCa|YW^j  
            DeleteOperation eID,count (s{RnD  
            count=count-1 6%fKuMpK(  
        End If ?c7*_<W5  
        count=count+1 XK: 9r{r{  
    Wend HO[wTB|D]  
    op.Type = "ShiftZ" +
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    op.val1 = taq-0.01 ^|TG$`M(w
 
    op.parent = parID SF5@Vg  
    AddOperation eID, op T}4/0yR2  
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    Print "Set pupil diameter = " & pupilDiam ZKXo-~=>  
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    'Update AZ Eye subassembly Description ;\[(- )f!=  
    eID = FindFullName( "Geometry.Arizona Eye" ) fm^@i;D  
    GetEntity eID, entity mWyqG*-Hb  
    entity.Description = "Accommodation = " & A & "D" lRveHB&V  
    SetEntity eID, entity ONCnVjZ  
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    Update MdXchO-Lyc  
    Print "DONE!" O)Y?=G)  
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End Sub PI*82,f3dE  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： i,|0@Vy  
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Accommodation = 4 Diopters iC*F
  
Pupil Diameter = 4 mm @c~)W8  
Set aqueous humor thickness = 2.81 KL ?@@7  
Set anterior lens radius = 10.4 and conic constant = -2.375869 8o/}}=m$  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 r%e KFS  
Set lens thickness = 3.927 ~u.T-0F  
Set lens index of refraction = 1.42672 Z(9u<  
Set pupil diameter = 4 ,:%"-`a%  
DONE! rYp3(k3