[分享]Arizona眼睛模型 [复制链接]

简介 Z?.*.<"Sj  
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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。 E/ZJ\@gzD  
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模型 hD1AK+y  
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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。 1Q SIZoK7  
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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. "yTh +=  
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光源 iyYY)roB  
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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。 8>Z$/1Mh  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 41o!2(e$  
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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。 GB?#1|,  
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视网膜的散射 3:joSQa  
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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。 ^70.g?(f[  
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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。 2ZbY|8X$r  
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脚本 Kn#xY3W6  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： ~,!hE&LE~  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 5u)^FIBj  
余下的脚本计算与屈光度有关的所有参数。 A Ok7G?Y  
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分析 }gi1?a59  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 mXU?+G0  
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脚本代码 >9tkx/J  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. .l( r8qY#  
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Dim entity As T_ENTITY wAYzR$i  
Dim op As T_OPERATION ?Y0$X>nm  
Dim mat As T_MODELMATERIAL ! jX+ox  
Dim A As Double ( X 'FQ  
Dim pupilDiam As Double Ec*--]j*c  
Dim eID As Long ay:\P.`5)  
Dim parID As Long h`EH~W0:z  
Dim count As Integer  Z|:_c  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Ag>>B9  
Dim tlens As Double, nlens As Double 1Fvv/Tj  
Dim curv As Double, conic As Double $: 4mOl  
Dim ok As Long j |'#5H`  
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Sub Main ZaRr2Z:!  
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    '用户输入对话框 zfjDb  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 vN0L(B  
        TextBox 220,21,40,21,.TextBox1 'default: 0 g~Nij~/  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 yA!3XUi  
        OKButton 40,91,90,21 4lY&=_K[)  
        CancelButton 190,91,90,21 lNh=>DPu  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 (Y'UvZlM%P  
        TextBox 220,49,40,21,.TextBox2 'default: 4 3)C6OF>7  
    End Dialog K{=r.W  
    Dim dlg As UserDialog {m+S{dWp  
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    ok = Dialog (dlg) c+E//X|  
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    If ok=0 Then    'cancel button was pressed ;Z!~A"~$>
 
        Print "Execution cancelled." $LxG>db  
        End m0BG9~p|  
    End If ,<;l"v(  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ^B<PD]  
    If dlg.TextBox1 = "" Then uGP[l`f|FQ  
        A = 0           'Default accommodation ubzb  
    Else kH>vD =q>  
        A = CDbl(dlg.TextBox1) c6?c>*z  
    End If uHUvntr  
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    If dlg.TextBox2 = "" Then t3  uB  
        pupilDiam = 4   'Default pupil diameter x%IXwP0  
    Else 'FPcAW^8  
        pupilDiam = CDbl(dlg.TextBox2) rnMG0  
    End If @H3s2|  
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    Print " " pjX%LsX\  
    Print "Accommodation = " & A & " Diopters" E,*JPK-A x  
    Print "Pupil Diameter = " & pupilDiam & " mm" wL8bs- U  
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    ' Calculate new parameters with accommodation z^ aCQ3E  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness AQnJxIL:  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens OQytgXED  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens Z%Tq1O  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens q7O,I`KaJ  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ==-7F3QP  
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    tlens = 3.767 + 0.04*A                  'Lens thickness vWqyZ-p,q  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction dl*_ m3T  
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    'Adjust parameters to account for accommodation VL_)]LR*)  
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    '************************************************************************* >~`Y
 
    'Aqueous thickness (Position of Lens) }|Hw0zP.  
    '************************************************************************* QmWC2$b  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) <_BqpZ^`  
    GetCustomElement eID, entity [ -9)T  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 4B:\  
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    ' Delete any shift(s) in z &#.x)>f  
    count = 0 vO}qjw  
    While GetOperationCount(eID)>count a-T*'F  
        GetOperation eID, count, op \b_-mnN"  
        If op.Type="ShiftZ" Then =gMaaGg p,  
            DeleteOperation eID,count Qq`3S>  
            count=count-1 92P,:2`a  
        End If 9l]UE0yTL/  
        count=count+1 07$/]eO%C  
    Wend R7E]*:0}  
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    'Set new shift in q*HAIw[<y  
    op.Type = "ShiftZ" paq8L{R  
    op.val1 = taq B8bvp:Ho|  
    op.parent = parID  'P@=/  
    AddOperation eID, op .K $p`WQ
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    Print "Set aqueous humor thickness = " & taq-0.55 J>f /u:.  
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    '************************************************************************* "_nX5J9  
    'Radius and conic constant of anterior lens t!6\7Vm/  
    '************************************************************************* y-E1]4?})  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) GIl:3iB49  
    GetConic eID, entity, curv, conic sl~b\j  
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    SetConic eID, entity, 1/Rant, CCant Y;fuh[#  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant #[no~&E  
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    '************************************************************************* =ied}a :[  
    'Radius and conic constant of posterior lens 21.YO]Et  
    '************************************************************************* Eem 2qKj  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) pWMiCXnW  
    GetConic eID, entity, curv, conic bcq@N  
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    SetConic eID, entity, 1/Rpost, CCpost 3cmbK  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost re7!p(W?,  
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    '************************************************************************* Vil@?Y"  
    'Lens thickness (Position of posterior lens surface) EwTS!gL  
    '************************************************************************* cNdu.c[@  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) slu$2-H  
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    ' Delete any z-shift(s) fy9uLl}h  
    count = 0  =Ov9Kf  
    While GetOperationCount(eID)>count ^it4z gx@  
        GetOperation eID, count, op OZ eiHX!  
        If op.Type="ShiftZ" Then V78Mq:7d  
            DeleteOperation eID,count g;$E1U=R-E  
            count=count-1 w+Ad$4Pf
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        End If gs$3)t  
        count=count+1 cL6 6gOEL  
    Wend (&q@~ dJ  
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    'Set new z-shift g* %bzfk=|  
    op.Type = "ShiftZ" }%_qx|(P|t  
    op.val1 = tlens >r~0SMQr  
    op.parent = parID fwRGT|":B  
    AddOperation eID, op 7}gA0fP9  
    Print "Set lens thickness = " & tlens 2q12yY f  
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    '************************************************************************* ;9K[~  
    'Lens index of refraction mG X\wta  
    '************************************************************************* X88F>1}  
    eID = FindMaterial( "Lens" ) AlUJ1^o)  
    GetModelMaterial eID, mat MY&<)|v\  

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    mat.Nd = nlens TV? ^c?{5  
    SetModelMaterial eID, mat L%f
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    Print "Set lens index of refraction = " & nlens 2%bhW,?I  
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    '************************************************************************* =1O?jrl~q  
    'Pupil diameter R j-jAH  
    '************************************************************************* *8/VSs  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 6{L F-`S%  
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    'Adjust pupil diameter (trimming volume inner hole) 6ezcS}:+  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" dZF8R  
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    ' Adjust pupil location to just in front of the lens k@
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    parID = FindFullName( "Geometry.Arizona Eye" ) ehU"*9  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) g/x_m.  
    count = 0 S3;lKr  
    While GetOperationCount(eID)>count av$  
        GetOperation eID, count, op *jGPGnSo  
        If op.Type="ShiftZ" Then CK=ARh#|  
            DeleteOperation eID,count R3cg2H  
            count=count-1 (s&ORoVGn  
        End If >;m{{nj  
        count=count+1 {Wh BoD  
    Wend Vw7WK  
    op.Type = "ShiftZ" iW'_R{)T  
    op.val1 = taq-0.01 }N@n{bu+  
    op.parent = parID QJQJR/g  
    AddOperation eID, op >cT
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    Print "Set pupil diameter = " & pupilDiam !f@XDW&R  
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    'Update AZ Eye subassembly Description nYhp`!W4;  
    eID = FindFullName( "Geometry.Arizona Eye" ) R<>tDwsZGa  
    GetEntity eID, entity Q@3B{  
    entity.Description = "Accommodation = " & A & "D" R#D#{cC(  
    SetEntity eID, entity 8'+7i8e  
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    Update <M=';h^w2  
    Print "DONE!" s_TD4~ $  
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End Sub ),yH=6  
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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： =Aj"j-r&{  
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Accommodation = 4 Diopters loLKm]yV  
Pupil Diameter = 4 mm x+K gc[r  
Set aqueous humor thickness = 2.81 .ByU  
Set anterior lens radius = 10.4 and conic constant = -2.375869 Ohi D  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 N70zjy4?fL  
Set lens thickness = 3.927 y>)MAzz~\  
Set lens index of refraction = 1.42672 Qd?CTYNsv  
Set pupil diameter = 4 u|T%Xy=LU  
DONE! V+.Q0$~F5  
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