[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 aRG2@5  
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。 Gj"7s8(/K|  
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模型 O5$/55PI  
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模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 d ;vT ~;  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. 'RRmIx2X  
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光源 :RoBl3X=  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 >e\9Bf_  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 64hk2a8  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 TXe$<4"  
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视网膜的散射 vAyFmdJ^  
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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。 K~@Mg1R  
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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。 os/vtyP:a  
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脚本 DGzw8|/(  
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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： Iu$K i  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 liXdNk8  
余下的脚本计算与屈光度有关的所有参数。 >nzdnF_&zW  
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分析 {mAU3x  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 .'Vww  
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脚本代码 I'|$}/\`  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. }Hn/I,/  
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Dim entity As T_ENTITY )E~79!  
Dim op As T_OPERATION L'F<ev  
Dim mat As T_MODELMATERIAL XGl+S  
Dim A As Double 8QM
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Dim pupilDiam As Double R)c'#St  
Dim eID As Long b,CaWg  
Dim parID As Long *hw\35%P`?  
Dim count As Integer J>\B`E  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Z,=7Tu bR#  
Dim tlens As Double, nlens As Double -{ H0g]  
Dim curv As Double, conic As Double ~$~5qwl  
Dim ok As Long B'fb^n<  

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Sub Main e
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    '用户输入对话框 w
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    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ^/r7@:  
        TextBox 220,21,40,21,.TextBox1 'default: 0 .FLy;_f+  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 sQ fFu  
        OKButton 40,91,90,21 ?Orxmxc 2  
        CancelButton 190,91,90,21 OVV]x{  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 0PWg;>^'  
        TextBox 220,49,40,21,.TextBox2 'default: 4 Rb.SY{}C  
    End Dialog _]Zs,Hy  
    Dim dlg As UserDialog R00eisd  
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    ok = Dialog (dlg) ;1a~pF S  
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    If ok=0 Then    'cancel button was pressed {HCzp,Y  
        Print "Execution cancelled." ;A*`e$  
        End ia MUsa{  
    End If |>#{[wko  
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    'Assign accommodation and pupil diameter & use defaults if field left empty + ~>Aj  
    If dlg.TextBox1 = "" Then F F|FU<  
        A = 0           'Default accommodation *m#Za<_Gv  
    Else w'm;82V:P-  
        A = CDbl(dlg.TextBox1) gntxNp[9T  
    End If @w?P7P<O`  
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    If dlg.TextBox2 = "" Then ihfiK|a  
        pupilDiam = 4   'Default pupil diameter 7:2WgLo  
    Else \Rp-;.I@6  
        pupilDiam = CDbl(dlg.TextBox2) ?W)A  
    End If |g//g\dd  
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    Print " " ;NHt7p8SE  
    Print "Accommodation = " & A & " Diopters" MP>dW nl  
    Print "Pupil Diameter = " & pupilDiam & " mm" 6=fSE=]DY  
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    ' Calculate new parameters with accommodation ;t|Ii8Ne  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness eY|  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens hX=A)73(  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens pNKhc#-w  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens FN8
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 3yB!M  
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    tlens = 3.767 + 0.04*A                  'Lens thickness d%o&+l#  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction  7*?}:  
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    'Adjust parameters to account for accommodation TL}++e 7+  
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    '************************************************************************* p{j.KI s7  
    'Aqueous thickness (Position of Lens) c1E'$- K@  
    '************************************************************************* PEc=\?  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) j
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    GetCustomElement eID, entity -}KC=,]vh  
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    parID = FindFullName( "Geometry.Arizona Eye" ) [rSR:V?"a  
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    ' Delete any shift(s) in z `0Oh_8"  
    count = 0 7eV di*  
    While GetOperationCount(eID)>count pP*a  
        GetOperation eID, count, op ;,?KI$K  
        If op.Type="ShiftZ" Then ;{U@qQD7  
            DeleteOperation eID,count d2H|LMhJ  
            count=count-1 2(#7[mgPI  
        End If %3ICI  
        count=count+1 -@0GcUE:r  
    Wend 9f<MQ6_UU  
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    'Set new shift in Pc NkAo  
    op.Type = "ShiftZ" {/ BT9|LI  
    op.val1 = taq 6jC`8l:  
    op.parent = parID <gQIq{B?  
    AddOperation eID, op RsY3V=u  
    Print "Set aqueous humor thickness = " & taq-0.55 !'cl"\h  
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    '************************************************************************* mqSQL}vR  
    'Radius and conic constant of anterior lens RT.D"WvT  
    '************************************************************************* .O0+H+  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 4UW_Do  
    GetConic eID, entity, curv, conic ZHm7Isa1  
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    SetConic eID, entity, 1/Rant, CCant U'<KC"f:'!  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant NbU[l  
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    '************************************************************************* ^$'z!+QRM  
    'Radius and conic constant of posterior lens Nw1#M%/!r!  
    '************************************************************************* Stu4t==U  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 8j=}u/T@F  
    GetConic eID, entity, curv, conic /XzH?n/{R  
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    SetConic eID, entity, 1/Rpost, CCpost &I (#Wy3  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost b"#WxgaF  
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    '************************************************************************* 4DL)rkO  
    'Lens thickness (Position of posterior lens surface) 2gCX}4^3b  
    '************************************************************************* 2-C!jAfd  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) o1h={ao  
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    ' Delete any z-shift(s) }Du}c3  
    count = 0 j]aoR  
    While GetOperationCount(eID)>count 2&^]k`Aj6D  
        GetOperation eID, count, op =A!@6Nw  
        If op.Type="ShiftZ" Then 4:dH]  
            DeleteOperation eID,count /7t>TY
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            count=count-1 "hzB9*"t  
        End If XbD4:i%  
        count=count+1 %0,#ADCqOe  
    Wend -8j+s}Q  
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    'Set new z-shift [`c^4E  
    op.Type = "ShiftZ" A<qTg`gA  
    op.val1 = tlens qT`k*i?  
    op.parent = parID JSTuXW  
    AddOperation eID, op P#XID 2;  
    Print "Set lens thickness = " & tlens 06N}k<10O  
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    '************************************************************************* ZRg;/sX]  
    'Lens index of refraction GJtZ&H  
    '************************************************************************* EioB%f3  
    eID = FindMaterial( "Lens" ) }5}.lJ:  
    GetModelMaterial eID, mat T QSzx%i2  
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    mat.Nd = nlens 2gq9k}38  
    SetModelMaterial eID, mat |,!
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    Print "Set lens index of refraction = " & nlens .QN>z-YA6:  
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    '************************************************************************* Ire\i7MF:  
    'Pupil diameter Xt@Z}B))pu  
    '************************************************************************* 7[5.> h  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) O^^C;U@U<1  
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    'Adjust pupil diameter (trimming volume inner hole) 1r]IogI  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" }9W4"e2)  
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    ' Adjust pupil location to just in front of the lens 7U2J xE  
    parID = FindFullName( "Geometry.Arizona Eye" ) o\3L}Y  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) I| b2acW  
    count = 0 }`,t$NV`  
    While GetOperationCount(eID)>count j&Wl0  
        GetOperation eID, count, op (r D_(%o  
        If op.Type="ShiftZ" Then B3 5E8/  
            DeleteOperation eID,count s!}ne"&0  
            count=count-1 "0cID3A$  
        End If JAX*hGhkh  
        count=count+1 |]ZYa.+:  
    Wend :"IE  
    op.Type = "ShiftZ" 5yiK+-iTs  
    op.val1 = taq-0.01 -QmO1U  
    op.parent = parID [ zEUH:9D  
    AddOperation eID, op DFd%9*N  
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    Print "Set pupil diameter = " & pupilDiam Wv/%^3  
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    'Update AZ Eye subassembly Description ZObhF#Y
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    eID = FindFullName( "Geometry.Arizona Eye" ) 
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    GetEntity eID, entity FTQ%JTgT  
    entity.Description = "Accommodation = " & A & "D" 8qEVOZjV&  
    SetEntity eID, entity dnb)/  
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    Update :E@3Vl#U  
    Print "DONE!" OI0;BBZ  
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End Sub eZdu2.;<  
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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： ]5$eAYq  
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Accommodation = 4 Diopters 0 rXxRQ  
Pupil Diameter = 4 mm 24)(5!:"  
Set aqueous humor thickness = 2.81 U
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Set anterior lens radius = 10.4 and conic constant = -2.375869 J<dVTxK12  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 >ey\jDr#O  
Set lens thickness = 3.927 8$ma;U d  
Set lens index of refraction = 1.42672 .72S oT  
Set pupil diameter = 4 P3nb2.  
DONE! X'`~s}vGO  
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