[分享]Arizona眼睛模型 [复制链接]

简介 1'ts>6b  
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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。 },<(VhP  
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模型 R"%zmA@o=  
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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。 4+Aht]$hC  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. 6Q\0v  
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光源 c
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 RN2^=$'.  
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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。 84(NylZ  
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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。 o3C7
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视网膜的散射 W&MZ5t,k=  
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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。 Jc8^m0_  
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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。 LdAWCBLS  
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脚本 (x)}k&B;  
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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： aL?+# j^"  
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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。 jg)+]r/hS  
余下的脚本计算与屈光度有关的所有参数。 \B\G=Y  
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分析 {Sl#z}@s  
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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。 VK)vb.:  
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脚本代码 A[7\!bq5  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. As}3VBd  
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Dim entity As T_ENTITY ?**9hu\BG  
Dim op As T_OPERATION ./7*<W:  
Dim mat As T_MODELMATERIAL r]+/"~a  
Dim A As Double ^pc?oDPSg  
Dim pupilDiam As Double |!Uul0O  
Dim eID As Long }F B]LLi  
Dim parID As Long T<a/GE/  
Dim count As Integer ZBY*C;[)*P  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double s*;rt  
Dim tlens As Double, nlens As Double s!g06F  
Dim curv As Double, conic As Double FN+x<VXo(  
Dim ok As Long " J4?Sb<  
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Sub Main ;#/Uo8  
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    '用户输入对话框 p~A6:"8s`=  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 +|K/*VVn`  
        TextBox 220,21,40,21,.TextBox1 'default: 0 S\poa:D`  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 nSSj&q-O  
        OKButton 40,91,90,21 S Boi|  
        CancelButton 190,91,90,21 {SRv=g  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 j9sLR  
        TextBox 220,49,40,21,.TextBox2 'default: 4 &Hj1jM'  
    End Dialog #;(Q \  
    Dim dlg As UserDialog xRrKrs&eE  
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    ok = Dialog (dlg) "KHe6otmi_  
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    If ok=0 Then    'cancel button was pressed N5F+h94z]  
        Print "Execution cancelled." yhsbso,5 a  
        End Ib}~Q@?2  
    End If 1nZ7xCDK98  
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    'Assign accommodation and pupil diameter & use defaults if field left empty Q2LAXTF]y  
    If dlg.TextBox1 = "" Then IxU#x*  
        A = 0           'Default accommodation p!o+8Xz5  
    Else DQy;W  ov  
        A = CDbl(dlg.TextBox1)
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    End If e_h`x+\:  
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    If dlg.TextBox2 = "" Then y**>l{!!  
        pupilDiam = 4   'Default pupil diameter b8O }XB  
    Else vO 3-B   
        pupilDiam = CDbl(dlg.TextBox2) 8h{;*Wr-  
    End If b/g~;| <  
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    Print " " Y{`hRz`  
    Print "Accommodation = " & A & " Diopters" W*Gp0pX  
    Print "Pupil Diameter = " & pupilDiam & " mm" /zTx+U.\I  
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    ' Calculate new parameters with accommodation _h1:{hF  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness FNHJHuTe  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens QG]*v=Z  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 3BK_$Fy  
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    tlens = 3.767 + 0.04*A                  'Lens thickness <,+6:NmT  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction yoVN|5  
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    'Adjust parameters to account for accommodation NVG`XL  
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    '************************************************************************* n1@ Or=5  
    'Aqueous thickness (Position of Lens) wg{Y6XyH  
    '************************************************************************* 9 :FzSD   
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) jKhj 7dR  
    GetCustomElement eID, entity A,f%0 eQR  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 1+NmiGKg  
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    ' Delete any shift(s) in z V1>>]]PS  
    count = 0 TM$Ek^fQ.  
    While GetOperationCount(eID)>count %q5iy0~P  
        GetOperation eID, count, op ba"a!#wA
 
        If op.Type="ShiftZ" Then v}^ f8nVR  
            DeleteOperation eID,count 90]{4]y;  
            count=count-1 !|;w(/  
        End If 3I.0uLjg^  
        count=count+1 K$Yc!4M  
    Wend '$5o5\  
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    'Set new shift in Bg0 aLU)[  
    op.Type = "ShiftZ" $C?G7Vs  
    op.val1 = taq ~zA{=|I2  
    op.parent = parID :>GT<PPD;  
    AddOperation eID, op _=oNQ  
    Print "Set aqueous humor thickness = " & taq-0.55
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    '************************************************************************* h| +(  
    'Radius and conic constant of anterior lens O-K!Bv^ Q  
    '************************************************************************* )bPF@'rF2  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) n\D3EP<s  
    GetConic eID, entity, curv, conic z0m[25FQG  
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    SetConic eID, entity, 1/Rant, CCant TAn.5 wH9t  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ^iwM(d]#5  
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    '************************************************************************* mca9 +v  
    'Radius and conic constant of posterior lens Lu?)Rya  
    '************************************************************************* vX
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Q|W!m0XO  
    GetConic eID, entity, curv, conic e{x|d?)8  
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    SetConic eID, entity, 1/Rpost, CCpost CJNz J(  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 4D\+_Ic3  
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    '************************************************************************* hrr;=q$  
    'Lens thickness (Position of posterior lens surface) ,w/f:-y  
    '************************************************************************* 6uH1dsD  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) @tLoU%  
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    ' Delete any z-shift(s) V6ioQx=K#  
    count = 0 fKY1=3  
    While GetOperationCount(eID)>count WPM<Qv L  
        GetOperation eID, count, op !OJSQB,  
        If op.Type="ShiftZ" Then K!9rH>`\  
            DeleteOperation eID,count Z0e+CEzq  
            count=count-1 m 5NF)eL  
        End If TIa`cU`  
        count=count+1 f-tV8  
    Wend 9h6
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    'Set new z-shift h;KI2k_^  
    op.Type = "ShiftZ" r_Rjjo  
    op.val1 = tlens ^JMSe-  
    op.parent = parID /z4xq'<  
    AddOperation eID, op VM3H&$d(h  
    Print "Set lens thickness = " & tlens cF[[_  
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    '************************************************************************* ^IGTGY]s  
    'Lens index of refraction m`c(J1Et  
    '************************************************************************* "A:wWb<
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    eID = FindMaterial( "Lens" ) 9CWUhS   
    GetModelMaterial eID, mat NoJo-vo*  
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    mat.Nd = nlens lm&C!{K  
    SetModelMaterial eID, mat Dg#Ab8  
    Print "Set lens index of refraction = " & nlens 3RRZVc* ^  
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    '************************************************************************* Z3R..vy
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    'Pupil diameter *qG=p`  
    '************************************************************************* `z3?ET  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) o0wep&@  
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    'Adjust pupil diameter (trimming volume inner hole) ;<q@>p[  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" AX
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    ' Adjust pupil location to just in front of the lens ,[bcyf  
    parID = FindFullName( "Geometry.Arizona Eye" ) SAG)vmm  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) -JZl?hY(  
    count = 0 fINM$ 6  
    While GetOperationCount(eID)>count oUw-l_M]  
        GetOperation eID, count, op 7B%@f9g  
        If op.Type="ShiftZ" Then #OWwg`AWv  
            DeleteOperation eID,count !4jS=Lhe>  
            count=count-1 <$D)uY K  
        End If aXC`yQ?  
        count=count+1 q{7s.m >  
    Wend 2%W(^Lj  
    op.Type = "ShiftZ" e`$v\7K  
    op.val1 = taq-0.01 {=g-zsc]K  
    op.parent = parID 4kg9
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    AddOperation eID, op 6g$04C3tHi  
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    Print "Set pupil diameter = " & pupilDiam  ]NAPvw#p  
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    'Update AZ Eye subassembly Description 2 yP#:T/z  
    eID = FindFullName( "Geometry.Arizona Eye" ) )X^nzhZ2O"  
    GetEntity eID, entity Gs?W7}<$  
    entity.Description = "Accommodation = " & A & "D" q]Qgg  
    SetEntity eID, entity !Q7  
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    Update j9u-C/Q\r  
    Print "DONE!" (tq)64XVz  
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End Sub \R-u+ci$ZY  
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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： %okEN!=  
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Accommodation = 4 Diopters *Nt6 Ufq6  
Pupil Diameter = 4 mm >M1/m=a  
Set aqueous humor thickness = 2.81 pb{P[-f  
Set anterior lens radius = 10.4 and conic constant = -2.375869 AN~1E@"  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 E?XA/z !  
Set lens thickness = 3.927 _ _)Z Q  
Set lens index of refraction = 1.42672 ,OasT!Sr  
Set pupil diameter = 4 Oy|9po  
DONE! +Zr03B  
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