[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 b$ 8R  
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。 ]NW_oRH  
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模型 * _usVg  
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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。 qOQ8a:]?  
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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. gCRPaF6  
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光源 ^HuB40  
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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。 plr3&T~,&S  
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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。 HHgv,bC!  
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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。 I;?PDhDb  
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视网膜的散射 Bz%wV-  
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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。 ApggTzh@  
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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=jSB#B  
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脚本 {od@Sl  
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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：  
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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。 >xF&>SDC  
余下的脚本计算与屈光度有关的所有参数。 nHZhP4W  
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分析 ![I|hB  
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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。 v<(+ l)Ln  
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脚本代码 BT$Oh4y4  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 3'0Jn6(  
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Dim entity As T_ENTITY zqQ[uO]m?  
Dim op As T_OPERATION i]@k'2N  
Dim mat As T_MODELMATERIAL JnqP`kYbTE  
Dim A As Double :>H{?  
Dim pupilDiam As Double
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Dim eID As Long !HhF*Rlr  
Dim parID As Long eQ6wEeB9  
Dim count As Integer ) jM-5}"  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double }1CvbB%,A  
Dim tlens As Double, nlens As Double c@nh>G:y{&  
Dim curv As Double, conic As Double
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Dim ok As Long d{B0a1P  
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Sub Main Z>X]'q03  

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    '用户输入对话框 V|awbff:  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ,C
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        TextBox 220,21,40,21,.TextBox1 'default: 0 U.I7p  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 d@b2XCh<K  
        OKButton 40,91,90,21 Are0Nj&?
 
        CancelButton 190,91,90,21 &%(SkL_]  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 XgeUS;qtta  
        TextBox 220,49,40,21,.TextBox2 'default: 4 hKnV
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    End Dialog 7*WO9R/  
    Dim dlg As UserDialog tuY=)?  
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    ok = Dialog (dlg) 1>2 /1>  
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    If ok=0 Then    'cancel button was pressed `JGW8
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        Print "Execution cancelled." vkG%w;  
        End ^4Se=Hr z2  
    End If $DnR[V}rR!  
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    'Assign accommodation and pupil diameter & use defaults if field left empty nhZ/^`Y<  
    If dlg.TextBox1 = "" Then 8A-*MU`+  
        A = 0           'Default accommodation VuK>lY&  
    Else WqCj;Tj|  
        A = CDbl(dlg.TextBox1) _oefp*iWS  
    End If WZTv  
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    If dlg.TextBox2 = "" Then lKqFuLHwF  
        pupilDiam = 4   'Default pupil diameter YZ<5-C  
    Else n 1^h;2gz  
        pupilDiam = CDbl(dlg.TextBox2) G"Ey%Q2K  
    End If m<*+^JN  
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    Print " " q$ j  
    Print "Accommodation = " & A & " Diopters" N\?__WlBK7  
    Print "Pupil Diameter = " & pupilDiam & " mm" OKu~Nb*  
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    ' Calculate new parameters with accommodation i`iR7UmHeR  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness [I<J6=  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ?T|0"|\"'  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens Aq>?G+  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens XV)ctF4  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens z 61Fq  
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    tlens = 3.767 + 0.04*A                  'Lens thickness QXy=|  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ) <w`:wD  
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    'Adjust parameters to account for accommodation Q;nC #cg  
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    '************************************************************************* )N\BC  
    'Aqueous thickness (Position of Lens) D& &71X '  
    '************************************************************************* (FGHt/!  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) S5UQ   
    GetCustomElement eID, entity +u&3pK>f  
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    parID = FindFullName( "Geometry.Arizona Eye" ) C!6D /S  
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    ' Delete any shift(s) in z u6MU @?  
    count = 0 #v6<
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    While GetOperationCount(eID)>count 6 Pdao{P  
        GetOperation eID, count, op :$P1ps3B  
        If op.Type="ShiftZ" Then gp'k(rGH  
            DeleteOperation eID,count "\5 T 6  
            count=count-1 z('t#J!b  
        End If 3Jj&wHp]  
        count=count+1 T;S6<J  
    Wend <P]%{msGH  
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    'Set new shift in ~K(mt0T)  
    op.Type = "ShiftZ" %;aB#:p6  
    op.val1 = taq ?<Mx*l  
    op.parent = parID `9\^.g)  
    AddOperation eID, op mSk";UCn  
    Print "Set aqueous humor thickness = " & taq-0.55 g{kjd2  
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    '************************************************************************* Jq8v69fyQ  
    'Radius and conic constant of anterior lens wk1/&  
    '************************************************************************* 79h'sp6;  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) PO:sF]5  
    GetConic eID, entity, curv, conic 6X4r2Vq  
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    SetConic eID, entity, 1/Rant, CCant nmyDGuzk  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ,,7hVw  
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    '************************************************************************* kD)]\  
    'Radius and conic constant of posterior lens \}YAQ'T  
    '************************************************************************* |M18/{  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) +NeoGnj  
    GetConic eID, entity, curv, conic #GUD^#Jh  
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    SetConic eID, entity, 1/Rpost, CCpost tOo\s&j  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost }2Y`Lr  
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    '************************************************************************* NR%_&%qQA  
    'Lens thickness (Position of posterior lens surface) 80Q%c(i  
    '************************************************************************* ^a1k"|E?f  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 53^3..E|  
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    ' Delete any z-shift(s) >Qg-dJt[  
    count = 0 -av=5hm  
    While GetOperationCount(eID)>count *V[I&dKq  
        GetOperation eID, count, op O.-A)S@  
        If op.Type="ShiftZ" Then  J2Qt!-  
            DeleteOperation eID,count I<Mb/!TQ  
            count=count-1 lc]cs D  
        End If S5YEz XG  
        count=count+1 ,v?FR }v  
    Wend ;*=7>"o'`  
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    'Set new z-shift b7gN|Hw5 H  
    op.Type = "ShiftZ" 4i<GqG  
    op.val1 = tlens $P2*q
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    op.parent = parID bHXoZix  
    AddOperation eID, op 7Rc>LI* '  
    Print "Set lens thickness = " & tlens b+L!p.:  
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    '************************************************************************* .*z$vl  
    'Lens index of refraction sN) xNz  
    '************************************************************************* RS@G.|  
    eID = FindMaterial( "Lens" ) SA%)xGRW  
    GetModelMaterial eID, mat BaMF5f+  
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    mat.Nd = nlens ~~Rq
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    SetModelMaterial eID, mat aEun *V^,  
    Print "Set lens index of refraction = " & nlens YtXd>@7  
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    '************************************************************************* 9Sl5jn  
    'Pupil diameter !\'HKk~V  
    '************************************************************************* /)?qD
 
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) y k\/Cf  
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    'Adjust pupil diameter (trimming volume inner hole) >\3N#S"PF  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ]3Jb$Q@  
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    ' Adjust pupil location to just in front of the lens 1qp
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    parID = FindFullName( "Geometry.Arizona Eye" ) 5XuQQ!`  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) kxmsrQ
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    count = 0 %MEWw  
    While GetOperationCount(eID)>count |;I"Oc.w^R  
        GetOperation eID, count, op "{c@}~  
        If op.Type="ShiftZ" Then 7h>,  
            DeleteOperation eID,count itcM-?  
            count=count-1 %zhSSB=BJ  
        End If X?(R!=a  
        count=count+1 z f>(Y7M  
    Wend VJ1rU mO~  
    op.Type = "ShiftZ" (nYGN$qC9  
    op.val1 = taq-0.01  @l&{ j  
    op.parent = parID H;[?8h(  
    AddOperation eID, op OM`Ws5W}f  
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    Print "Set pupil diameter = " & pupilDiam E 5mYFVK  
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    'Update AZ Eye subassembly Description Ds{DVdqA$c  
    eID = FindFullName( "Geometry.Arizona Eye" ) 2(P<TP._E  
    GetEntity eID, entity ?=HoU3  
    entity.Description = "Accommodation = " & A & "D" _{GD\Ai_W  
    SetEntity eID, entity WHu[A/##']  
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    Update L[U?{  
    Print "DONE!" B3I0H6O  
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End Sub nj-LG!"a  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： L(C0236r  
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Accommodation = 4 Diopters gf^y3F[\  
Pupil Diameter = 4 mm  "Id1H  
Set aqueous humor thickness = 2.81 4E$d"D5]>p  
Set anterior lens radius = 10.4 and conic constant = -2.375869 A-h[vP!v|  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 +,)Iv_Xl$  
Set lens thickness = 3.927 7Jpq7;  
Set lens index of refraction = 1.42672 " BU4\QF-  
Set pupil diameter = 4 Kp!A ay  
DONE! R{6M(!x  
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