[技术]Arizona眼睛模型 [复制链接]

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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。 C,,T7(: k  
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模型 l[ko)%7V  
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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。  H#F"n"~$  
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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. HF*~bL  
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光源 uA`e  
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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。 )~P<ruk>,C  
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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。 +VIEDV+   
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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。 SFzoRI=q
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视网膜的散射 ;[zZI~wh  
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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。 yyPj!<.MGP  
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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。 lYS4Q`z$  
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脚本 ?h7[^sxJ  
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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： z:n JN%Qb  
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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。 &=8ZGjR< }  
余下的脚本计算与屈光度有关的所有参数。 NFU=PS$  
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分析 hHt.No  
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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。 xAsy07J?  
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脚本代码 sx9[#6~{Y  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. jaTCRn3|<  
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Dim entity As T_ENTITY lKirc2  
Dim op As T_OPERATION a 8jG')zg  
Dim mat As T_MODELMATERIAL F,5}3$  
Dim A As Double t5p#g<$  
Dim pupilDiam As Double B@3>_};Ct  
Dim eID As Long v^IMN3^W  
Dim parID As Long <RkJ7Z^  
Dim count As Integer `O=LQ m`  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 9/\=6vC|  
Dim tlens As Double, nlens As Double avv/mEf-f  
Dim curv As Double, conic As Double ^q~.
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Dim ok As Long 1 pzd  
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Sub Main =1kjKE !  
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    '用户输入对话框 ;UjP0z
  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 !91<K{#A{  
        TextBox 220,21,40,21,.TextBox1 'default: 0 hWu#}iN  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Z Q9's  
        OKButton 40,91,90,21 XN'X&J  
        CancelButton 190,91,90,21 E?f*Z{~,  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 @}N;C..Y$  
        TextBox 220,49,40,21,.TextBox2 'default: 4 !FnH;  
    End Dialog 3412znM&  
    Dim dlg As UserDialog y+[wlo&WC  
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    ok = Dialog (dlg) mCpoaGV_  
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    If ok=0 Then    'cancel button was pressed 8<ri"m,  
        Print "Execution cancelled." DU4Prjb'  
        End E~!FEl;  
    End If 8>jd2'v{  
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    'Assign accommodation and pupil diameter & use defaults if field left empty 0:Lm=9o  
    If dlg.TextBox1 = "" Then whg?X&j\V  
        A = 0           'Default accommodation pRdO4?l  
    Else 1z(y>`ZBq  
        A = CDbl(dlg.TextBox1) dQFx]p3L  
    End If WS0RvBvb  
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    If dlg.TextBox2 = "" Then e{9(9qE"  
        pupilDiam = 4   'Default pupil diameter K`1\3J)  
    Else yyHr. C  
        pupilDiam = CDbl(dlg.TextBox2) 0)lG~_q  
    End If L7*~8Y  
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    Print " " pr-!otz  
    Print "Accommodation = " & A & " Diopters" MhB kr{8  
    Print "Pupil Diameter = " & pupilDiam & " mm" R\=y/tw0H  
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    ' Calculate new parameters with accommodation 1<qq69x  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness V9m1n=r  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens A|@d4+  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens Rf\>bI<.  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 9W7H",
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens NLF{W|X  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Kc\0-3 Z  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction GL1!Z3  
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    'Adjust parameters to account for accommodation 5,qfr!hN,  
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    '************************************************************************* *-Y
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    'Aqueous thickness (Position of Lens) 4oOe  
    '************************************************************************* t9x.O  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) (F7!&]8%  
    GetCustomElement eID, entity :/Nz' n  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 37!}8  
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    ' Delete any shift(s) in z <  v_?}  
    count = 0 e$tKKcj0T  
    While GetOperationCount(eID)>count P*(lc:  
        GetOperation eID, count, op M>_S%V4a  
        If op.Type="ShiftZ" Then  c:~o e  
            DeleteOperation eID,count ScfW;  
            count=count-1 "$:nz}  
        End If mrd(\&EhA  
        count=count+1 R{6.O+j`  
    Wend -acW[$t  
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    'Set new shift in #ZGWU_l}  
    op.Type = "ShiftZ" ;Fuxj
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    op.val1 = taq sbNCviKP  
    op.parent = parID JVTG3:zD  
    AddOperation eID, op oChcEx%  
    Print "Set aqueous humor thickness = " & taq-0.55 Mk[_y
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    '************************************************************************* O*yc8fUI  
    'Radius and conic constant of anterior lens WFN5&7$W  
    '************************************************************************* n2Ycq&O  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ]b<k%  
    GetConic eID, entity, curv, conic -F|(Y1OE  
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    SetConic eID, entity, 1/Rant, CCant \kWceu}H,  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant yNY1g?E  
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    '************************************************************************* /1tqTi  
    'Radius and conic constant of posterior lens }N4=~'R  
    '************************************************************************* GXRK+RHuBi  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) bEy j8=P;  
    GetConic eID, entity, curv, conic |$9k z31  
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    SetConic eID, entity, 1/Rpost, CCpost |'=R`@w~0  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost "vjz
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    '************************************************************************* 5oWR}qqFK  
    'Lens thickness (Position of posterior lens surface)  nKkI  
    '************************************************************************* WZ"x\K-;  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" )
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    ' Delete any z-shift(s) |'mgo  
    count = 0 |7UR_(}KC  
    While GetOperationCount(eID)>count ]X4A)%i  
        GetOperation eID, count, op Scs \nF2  
        If op.Type="ShiftZ" Then eSywWSdf0  
            DeleteOperation eID,count .azdAq'r&\  
            count=count-1 w]F(o  
        End If =JNoC01D  
        count=count+1 ) <^9`  
    Wend SukRJvi  
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    'Set new z-shift 3MiNJi#=2  
    op.Type = "ShiftZ" EQz`o+  
    op.val1 = tlens Ry[V
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    op.parent = parID JyYg)f  
    AddOperation eID, op #ra:^9;Es:  
    Print "Set lens thickness = " & tlens srJ,Jr(  
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    '************************************************************************* N~g'Z `  
    'Lens index of refraction ;&^S-+  
    '************************************************************************* -&D~TL#  
    eID = FindMaterial( "Lens" ) lJu2}XRiU  
    GetModelMaterial eID, mat #U(dleT8  
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    mat.Nd = nlens "+r8izB  
    SetModelMaterial eID, mat \BbemCPAm  
    Print "Set lens index of refraction = " & nlens O,]t.1V  
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    '************************************************************************* I%b, H`  
    'Pupil diameter ZVVK:dDgt  
    '************************************************************************* C B=H1+  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 5A Vo#}&\  
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    'Adjust pupil diameter (trimming volume inner hole) 4)*8&  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" )#9/vIQ  
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    ' Adjust pupil location to just in front of the lens S3`zB?7,  
    parID = FindFullName( "Geometry.Arizona Eye" ) G?8LYg!-  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 'h.{fKG]ME  
    count = 0 {(Drw~/@  
    While GetOperationCount(eID)>count | ?~-k[|  
        GetOperation eID, count, op &M*&oi (  
        If op.Type="ShiftZ" Then q[] "`?  
            DeleteOperation eID,count }rxFX  
            count=count-1 E@7";&\-8  
        End If kNMhMEez  
        count=count+1 "+[
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    Wend .&TJSIx$  
    op.Type = "ShiftZ" qi.|oL9p  
    op.val1 = taq-0.01 (`k0tC2  
    op.parent = parID c&e?_@}|  
    AddOperation eID, op ^EN_C<V;"d  
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    Print "Set pupil diameter = " & pupilDiam kZBIX
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    'Update AZ Eye subassembly Description  ^GB9!d.  
    eID = FindFullName( "Geometry.Arizona Eye" ) sFC&DTb?  
    GetEntity eID, entity bBW(# Q_a  
    entity.Description = "Accommodation = " & A & "D" Ts:3_4-k  
    SetEntity eID, entity J@=1zL  
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    Update |g}! F-  
    Print "DONE!" Y [0S  
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End Sub @ZK#Y){  
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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： tYC`?HT  
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Accommodation = 4 Diopters \_#0Z+pX  
Pupil Diameter = 4 mm KM*sLC#  
Set aqueous humor thickness = 2.81 U#gHc:$  
Set anterior lens radius = 10.4 and conic constant = -2.375869 _Z~wpO}/  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 &kB[jz_[A  
Set lens thickness = 3.927 (9CB&LZ(+E  
Set lens index of refraction = 1.42672 !:,d^L!bh  
Set pupil diameter = 4 2^Tj7@  
DONE! hY7Q$B<