[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 PR=:3-#R  
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。 [pOQpfo\  
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模型 ]q DhGt  
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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。 h4x*C=?A  
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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. CZ*c["x2  
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光源 bE _=L=NG  
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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。 8munw  
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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。 SovK|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。 :9N~wd  
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视网膜的散射 {"l_x]q  
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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。 %1fH-:c=C0  
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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。 ]YQ[ )  
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脚本 v;"
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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： =,&PD(.  
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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。 laN:H mR8  
余下的脚本计算与屈光度有关的所有参数。 u5^fiw]C  
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分析 mw)KyU#l,:  
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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。 S'qEBz  
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脚本代码 O_aZ\28};C  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. rLO1Sv  
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Dim entity As T_ENTITY /n;-f%dL  
Dim op As T_OPERATION T X.YTU  
Dim mat As T_MODELMATERIAL ?_q e 2R.  
Dim A As Double X[b=25Ct  
Dim pupilDiam As Double V8ka*VJ(B  
Dim eID As Long j#d=V@=a  
Dim parID As Long vc
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Dim count As Integer GlYNC&,VL  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ^6s<  
Dim tlens As Double, nlens As Double 9,\b$?9  
Dim curv As Double, conic As Double d:*,HzG  
Dim ok As Long R=P=?U.  
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Sub Main 5Z/xY&  
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    '用户输入对话框 4E]w4BG)  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 M72.  
        TextBox 220,21,40,21,.TextBox1 'default: 0 (hej
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        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 8P5yaS_  
        OKButton 40,91,90,21 c?B@XIl  
        CancelButton 190,91,90,21 "&*O7cs$pA  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 %LeG.~?  
        TextBox 220,49,40,21,.TextBox2 'default: 4 b,"gBg  
    End Dialog zu}oeAQc$  
    Dim dlg As UserDialog ! iuDmL  
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    ok = Dialog (dlg) mxk :P  
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    If ok=0 Then    'cancel button was pressed _7r<RZ  
        Print "Execution cancelled." 0o~? ]C  
        End Z18T<e  
    End If vw VeHjR  
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    'Assign accommodation and pupil diameter & use defaults if field left empty \'Oi0qo>  
    If dlg.TextBox1 = "" Then pEgQ) 9\  
        A = 0           'Default accommodation 21'I-j  
    Else 94 58.!3  
        A = CDbl(dlg.TextBox1) BM5+;h !  
    End If |O3wAxc3W  
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    If dlg.TextBox2 = "" Then Hhx"47:  
        pupilDiam = 4   'Default pupil diameter ;hb;%<xqT  
    Else _b8&$\
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        pupilDiam = CDbl(dlg.TextBox2) Ji4xor  
    End If 5{nERKaPf  
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    Print " " JDPn   
    Print "Accommodation = " & A & " Diopters" EH{m~x[Ei  
    Print "Pupil Diameter = " & pupilDiam & " mm" BSt^QH-'  
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    ' Calculate new parameters with accommodation ybLl[K(D=  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness y#F`yXUj  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 4/UY*Us&  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens UhKC:<%  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens }ie O  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens `-@8IZ7  
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    tlens = 3.767 + 0.04*A                  'Lens thickness {l$DNnS  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction XY %er  
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    'Adjust parameters to account for accommodation \Ps}1)wT  
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    '************************************************************************* *IBT!@*Q&  
    'Aqueous thickness (Position of Lens) 5cj]Y)I-~  
    '************************************************************************* @BQJKPF*  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) Mttt]]  
    GetCustomElement eID, entity `
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    parID = FindFullName( "Geometry.Arizona Eye" ) e4:,W+g,9  
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    ' Delete any shift(s) in z A|jmp~@K)+  
    count = 0 2to~
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    While GetOperationCount(eID)>count =' %r"_`}  
        GetOperation eID, count, op ^`M,ju  
        If op.Type="ShiftZ" Then y04md A6<  
            DeleteOperation eID,count RcJ.=?I!  
            count=count-1 6/{V#.(  
        End If !O|d,)$q  
        count=count+1 J,N='~kfh  
    Wend QuFzj`(  
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    'Set new shift in z =mDd  
    op.Type = "ShiftZ" w:[1,rRvT  
    op.val1 = taq B%y?+4;zA  
    op.parent = parID W5 l)m
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    AddOperation eID, op MU_8bK9m  
    Print "Set aqueous humor thickness = " & taq-0.55 2ed4xhV  
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    '************************************************************************* 2;8I0BH*'  
    'Radius and conic constant of anterior lens jnF-kia  
    '************************************************************************* m@(8-_  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) VtM:~|v  
    GetConic eID, entity, curv, conic j&
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    SetConic eID, entity, 1/Rant, CCant p7SX,kpt>  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ^7b[spqE  
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    '************************************************************************* SNLZU%jan  
    'Radius and conic constant of posterior lens qH1k  
    '************************************************************************* Evjvaa^  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Tt^PiaS!  
    GetConic eID, entity, curv, conic IZ9L ;"}  
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    SetConic eID, entity, 1/Rpost, CCpost W^(:\IvV  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost A=N &(k  
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    '************************************************************************* #:q$sKQ_$  
    'Lens thickness (Position of posterior lens surface) <H; z4  
    '************************************************************************* _aJo7  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ,Z3 (`ftC  
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    ' Delete any z-shift(s) %#AM }MWIa  
    count = 0 5Q/&,NP  
    While GetOperationCount(eID)>count 30BFwNE  
        GetOperation eID, count, op GbFtX\s+5j  
        If op.Type="ShiftZ" Then #\P
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            DeleteOperation eID,count j<*  
            count=count-1 hq[:U?!Tt  
        End If @%FLT6MY  
        count=count+1 ,Wbr; zb  
    Wend NE~R&ym9  
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    'Set new z-shift g$^:2MT"aQ  
    op.Type = "ShiftZ" ~8oti4  
    op.val1 = tlens h)NZG6R  
    op.parent = parID _ ^2\/@  
    AddOperation eID, op {fd/:B 7T  
    Print "Set lens thickness = " & tlens P0mY/bBU  
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    '************************************************************************* ;#i$5L!*B  
    'Lens index of refraction tf
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    '************************************************************************* q.}M^iDe  
    eID = FindMaterial( "Lens" ) 5%6{ ePh{  
    GetModelMaterial eID, mat sxK|0i}6  
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    mat.Nd = nlens *ku}.n  
    SetModelMaterial eID, mat eb` !  
    Print "Set lens index of refraction = " & nlens nO\c4#ce  
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    '************************************************************************* {0(:5%  
    'Pupil diameter `)aIFAW  
    '************************************************************************* xj!G9x<!  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) uY_vX\;67z  
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    'Adjust pupil diameter (trimming volume inner hole) Nn/f*GDvK  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" .#OD=wkN0  
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    ' Adjust pupil location to just in front of the lens j@o \d%.'!  
    parID = FindFullName( "Geometry.Arizona Eye" ) @CB&*VoB  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) i"_@iN0N  
    count = 0 vyA `Z1  
    While GetOperationCount(eID)>count E2nsBP=5C  
        GetOperation eID, count, op + g*s%^(E  
        If op.Type="ShiftZ" Then 2=%R>&]*  
            DeleteOperation eID,count AY(z9&;6  
            count=count-1 llE_-M2gH  
        End If 2?}5U)Hg  
        count=count+1 o0)k5P~<~  
    Wend v<AFcY  
    op.Type = "ShiftZ" ~u.((GM  
    op.val1 = taq-0.01 6rll0c~  
    op.parent = parID lP;X=
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    AddOperation eID, op n5U-D0/Q  
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    Print "Set pupil diameter = " & pupilDiam {/2 _"H3:  
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    'Update AZ Eye subassembly Description DkA@KS1Dq  
    eID = FindFullName( "Geometry.Arizona Eye" ) 1w$X;q"  
    GetEntity eID, entity -}G>{5.A  
    entity.Description = "Accommodation = " & A & "D" +M{A4nYY|1  
    SetEntity eID, entity 1 k\~%  

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    Update R^f-j-$o]  
    Print "DONE!" [dIlt"2fV  
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End Sub (X?et &  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： Q13>z%Rge  
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Accommodation = 4 Diopters U?e.)G  
Pupil Diameter = 4 mm DlF6tcoI  
Set aqueous humor thickness = 2.81 HxnWM\p  
Set anterior lens radius = 10.4 and conic constant = -2.375869 '\wZKYVN  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 ',l}$]y5  
Set lens thickness = 3.927 &57s//PrX  
Set lens index of refraction = 1.42672 k.6gX<T  
Set pupil diameter = 4 +\s&v!  
DONE! 2S@aG%-)  
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