[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 $(1t~u<17  
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。 }<Ydj .85  
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模型 Ws2q/[\oz  
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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。 Qf:e;1F!  
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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. g@H<Q('fJ  
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光源 %Wtf24'o;v  
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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。 A}(xH`A  
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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。 [if(B\&  
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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。 B)q}]Qn  
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视网膜的散射 P2'c{],3V  
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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。 7FwtBO  
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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。 a`Bp^(f}  
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脚本 w5Fk#zJv  
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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： bB@=J~l4  
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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。 V@0T&#  
余下的脚本计算与屈光度有关的所有参数。 t__f=QB/  
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分析 :V(C+bm *  
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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。 m03dL^(   
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脚本代码 J@_M%eN  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. J5a8U&A  
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Dim entity As T_ENTITY ]Mq-67  
Dim op As T_OPERATION 2Ys=/mh  
Dim mat As T_MODELMATERIAL 39^+;Mev  
Dim A As Double shB3[W{}!)  
Dim pupilDiam As Double rk=/iD  
Dim eID As Long @o[ZJ4>*  
Dim parID As Long 3ZT3I1/D  
Dim count As Integer 6O?zi|J[:  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double $\/i t  
Dim tlens As Double, nlens As Double YUSrZ9Yg  
Dim curv As Double, conic As Double z*HM_u  
Dim ok As Long @Mg&T
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Sub Main T=NLBJ  
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    '用户输入对话框 o0AT&<K  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 :V$\y up  
        TextBox 220,21,40,21,.TextBox1 'default: 0 Jd `Qa+  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 lOA EM  
        OKButton 40,91,90,21 i&(1<S>P  
        CancelButton 190,91,90,21 wv3*o10_w8  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 HH6n3c!:mm  
        TextBox 220,49,40,21,.TextBox2 'default: 4 vo Et\H  
    End Dialog v2gk1a&  
    Dim dlg As UserDialog a /]FlT  
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    ok = Dialog (dlg) 3L2NenJB  
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    If ok=0 Then    'cancel button was pressed h@JX?LzZS  
        Print "Execution cancelled." -[N9"Z,  
        End {$t*XTY6R  
    End If BN(=LQ2["  
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    'Assign accommodation and pupil diameter & use defaults if field left empty OL_#Uu  
    If dlg.TextBox1 = "" Then  G>?kskm  
        A = 0           'Default accommodation Z=$-S(>J  
    Else 0"j:-1  
        A = CDbl(dlg.TextBox1) FD!8
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    End If ;\|GU@K{hC  
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    If dlg.TextBox2 = "" Then nGX3_-U4  
        pupilDiam = 4   'Default pupil diameter ;k0Jl0[}  
    Else m*1  
        pupilDiam = CDbl(dlg.TextBox2) FaJK R  
    End If hrJ(][8  
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    Print " " Dl~(NLM  
    Print "Accommodation = " & A & " Diopters" RFsUb:%V7-  
    Print "Pupil Diameter = " & pupilDiam & " mm" 4cy,'B  
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    ' Calculate new parameters with accommodation )Vy0V=  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness {o^tSEN!-
 
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens Uufig)6  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 2\&3x}@  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens vaQsG6q[  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 3 ;"[WOv  
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    tlens = 3.767 + 0.04*A                  'Lens thickness mc`Z;D/mt  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction [So1`IA6  
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    'Adjust parameters to account for accommodation G*_
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    '************************************************************************* R<I#. KD  
    'Aqueous thickness (Position of Lens) O..{wdZy  
    '************************************************************************* `, ]ui*  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) rS!@AgPLE  
    GetCustomElement eID, entity ,K@[+ R!  
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    parID = FindFullName( "Geometry.Arizona Eye" ) |Wa.W0A  
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    ' Delete any shift(s) in z H}_R`S  
    count = 0 cGm?F,/`  
    While GetOperationCount(eID)>count V=&M\58  
        GetOperation eID, count, op /Q)I5sL@E  
        If op.Type="ShiftZ" Then sMVk]Mb  
            DeleteOperation eID,count x'?p?u~[  
            count=count-1 B R  
        End If C6F7,v62  
        count=count+1 RiAMW|M"C  
    Wend <-' !I&  
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    'Set new shift in %A3m%&(m&%  
    op.Type = "ShiftZ" {7DXSe4  
    op.val1 = taq G0Z5h  
    op.parent = parID IS!OO<  
    AddOperation eID, op iOZ#}"  
    Print "Set aqueous humor thickness = " & taq-0.55 +w.$"dF!  
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    '************************************************************************* CV=qcD  
    'Radius and conic constant of anterior lens [aA@V0l  
    '************************************************************************* w-R.)  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) u23_*W\  
    GetConic eID, entity, curv, conic zx$1.IM"4  
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    SetConic eID, entity, 1/Rant, CCant *aS+XnT/  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant uD?G\"L i  
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    '************************************************************************* 9.xRDk  
    'Radius and conic constant of posterior lens ia_@fQ  
    '************************************************************************* .hG*mXw>  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) xk/-TXB 0  
    GetConic eID, entity, curv, conic uxDM #  
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    SetConic eID, entity, 1/Rpost, CCpost Q
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    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 4'`P+p"A  
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    '*************************************************************************  7FY2a  
    'Lens thickness (Position of posterior lens surface) +XO\#$o>W  
    '************************************************************************* ))Z>$\<:  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ,YvOk|@R  
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    ' Delete any z-shift(s) Q~0>GOq*  
    count = 0 T\$i=,_$  
    While GetOperationCount(eID)>count _4)z:?G5  
        GetOperation eID, count, op %1jcY0zEQ  
        If op.Type="ShiftZ" Then |LbAW/9a  
            DeleteOperation eID,count <B0f  
            count=count-1 JrY*K|YdW  
        End If rq!
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        count=count+1 &V~l(1  
    Wend j-R*!i  
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    'Set new z-shift 2'-"&d+O  
    op.Type = "ShiftZ" 8 I_  
    op.val1 = tlens gELG/6l  
    op.parent = parID KgkRs?'z  
    AddOperation eID, op {]}94T~/k  
    Print "Set lens thickness = " & tlens QM3DB  
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    '************************************************************************* 6*>Lud  
    'Lens index of refraction vaP`'  
    '*************************************************************************

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    eID = FindMaterial( "Lens" ) %EVgSF!r  
    GetModelMaterial eID, mat o.fqJfpj  
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    mat.Nd = nlens =HsE:@  
    SetModelMaterial eID, mat =(7nl#o  
    Print "Set lens index of refraction = " & nlens b=/'cQ  
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    '************************************************************************* P][jB  
    'Pupil diameter =iKl<CqI$E  
    '************************************************************************* 7>j~;p{  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) YVDFcN9v  
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    'Adjust pupil diameter (trimming volume inner hole) :[
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" *QiQ,~Ep  
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    ' Adjust pupil location to just in front of the lens 1s.2z[B~  
    parID = FindFullName( "Geometry.Arizona Eye" ) 9)'f)60^  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ;50&s .gZ  
    count = 0 \_8wU'7  
    While GetOperationCount(eID)>count m:?"|.]  
        GetOperation eID, count, op kc^,V|Nbq6  
        If op.Type="ShiftZ" Then 3)W zX  
            DeleteOperation eID,count esnq/  
            count=count-1 PZusYeV8b  
        End If _#:/ ~Jp  
        count=count+1 (n*:LS=0  
    Wend /v+)#[]>  
    op.Type = "ShiftZ" W/ Q*NB  
    op.val1 = taq-0.01 !>`Fg>uy  
    op.parent = parID 1Q>nS[  
    AddOperation eID, op GcdJf/k  
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    Print "Set pupil diameter = " & pupilDiam z2uL[deN'"  
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    'Update AZ Eye subassembly Description MY@&^71i4  
    eID = FindFullName( "Geometry.Arizona Eye" ) }LT&BNZj  
    GetEntity eID, entity Xv-p7$?f  
    entity.Description = "Accommodation = " & A & "D" Y/FPkH4  
    SetEntity eID, entity  L\PmT  
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    Update 2aM7zP[Z  
    Print "DONE!" ">oySo.B?  
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End Sub E7
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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： W}CM;~*L  
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Accommodation = 4 Diopters IA@>'O  
Pupil Diameter = 4 mm tR|dnC4U  
Set aqueous humor thickness = 2.81 w*ans}P7  
Set anterior lens radius = 10.4 and conic constant = -2.375869 4a-JC"  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 I x%>aee  
Set lens thickness = 3.927 pUXoSnIq:  
Set lens index of refraction = 1.42672 H;1@]|sH#  
Set pupil diameter = 4 @b,Az{EH  
DONE! 3#>W\_FY*D  
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