[技术]Arizona眼睛模型 [复制链接]

简介 M<"H1>q@  
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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。 bTN0n  
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模型 G'qGsKf\  
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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。 1ZK~i  
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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. .8K ~ h  
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光源 AD/7k3:  
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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。 :VEy\ R>W  
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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。 r=o\!sh[  
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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。 ehCZhi~  
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视网膜的散射 jJfV_#'N'  
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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。 MH8Selnv  
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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。 NtnKS@Ht  
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脚本 ^s=p'&6  
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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： {_{&t>s2  
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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。 'Oe}Ja  
余下的脚本计算与屈光度有关的所有参数。 !ufSO9eDx"  
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分析 4}\Dr %US  
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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。 ~Uet)y<  
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脚本代码 ,Q5Z<\  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. HYkZMVH{  
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Dim entity As T_ENTITY =H\ig%%E@  
Dim op As T_OPERATION ]_ON\v1  
Dim mat As T_MODELMATERIAL CAPPOh  
Dim A As Double oNfNe^/T  
Dim pupilDiam As Double 07?|"c.  
Dim eID As Long 8+irul{H_  
Dim parID As Long k^ZcgHHgb  
Dim count As Integer qL03iV#h*V  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 3~%wA(|A  
Dim tlens As Double, nlens As Double =n}+p>\s  
Dim curv As Double, conic As Double d&'}~C`~k  
Dim ok As Long '*PJ-=G  
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Sub Main @%5$x]^  
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    '用户输入对话框 %z_PEqRj  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 h xCt[G@  
        TextBox 220,21,40,21,.TextBox1 'default: 0 }Z~& XL=  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 _qPd)V6yb  
        OKButton 40,91,90,21 d1`us G"  
        CancelButton 190,91,90,21 *k]izWsV*  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 gUcG#  
        TextBox 220,49,40,21,.TextBox2 'default: 4 0{Kb1Ut  
    End Dialog Vf'r6Rf  
    Dim dlg As UserDialog Y;L
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    ok = Dialog (dlg) @\=%M^bx  
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    If ok=0 Then    'cancel button was pressed wd/"! A4(  
        Print "Execution cancelled." l9%oKJ;  
        End k3/V$*i,1b  
    End If ]y3'6!
 
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    'Assign accommodation and pupil diameter & use defaults if field left empty Q+O3Wgjy  
    If dlg.TextBox1 = "" Then Dm"@59x  
        A = 0           'Default accommodation m 8Q[+_:$H  
    Else vPV=K+1  
        A = CDbl(dlg.TextBox1) jG0o-x=X  
    End If W* XG9  
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    If dlg.TextBox2 = "" Then B^z3u=ll  
        pupilDiam = 4   'Default pupil diameter (mOUbO8  
    Else Z?vbe}pUM  
        pupilDiam = CDbl(dlg.TextBox2) FK$?8Jp  
    End If s5s'$|h"  
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    Print " " \eD{bD  
    Print "Accommodation = " & A & " Diopters" Y+k)d^6r  
    Print "Pupil Diameter = " & pupilDiam & " mm" SLa\F  
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    ' Calculate new parameters with accommodation 5df~] -=0Y  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness xJvM l`2;  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens * 7
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    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens A&
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens l>i<J1  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens {jOCz1J  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Y6|8;2E  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Ol,Tw=?  
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    'Adjust parameters to account for accommodation a!1\,.  
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    '************************************************************************* m17H#!`  
    'Aqueous thickness (Position of Lens) F+Qp mVU  
    '************************************************************************* _?M71>3$.  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) g,5r)FU`  
    GetCustomElement eID, entity F8\nAX  
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    parID = FindFullName( "Geometry.Arizona Eye" ) Y5}<7s\UDO  
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    ' Delete any shift(s) in z vwZrvjP2  
    count = 0 ;NrN#<j(!  
    While GetOperationCount(eID)>count UIUCj8QJg  
        GetOperation eID, count, op k{/2vV[`]  
        If op.Type="ShiftZ" Then 'V reO52  
            DeleteOperation eID,count H0Q.; !^  
            count=count-1 Rw$>()}H8  
        End If \X5>HPB  
        count=count+1 3Z*'  
    Wend k!gf
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    'Set new shift in SBBDlr^P  
    op.Type = "ShiftZ" kKV`9&d
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    op.val1 = taq Rh7unJ
 
    op.parent = parID 
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    AddOperation eID, op -saisH6  
    Print "Set aqueous humor thickness = " & taq-0.55 ;%r#pv~  
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    '************************************************************************* 1C[j:Ly/  
    'Radius and conic constant of anterior lens DwXzmp[qWH  
    '************************************************************************* *5DOTWos  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) $7{|  
    GetConic eID, entity, curv, conic 7l"N%e  
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    SetConic eID, entity, 1/Rant, CCant rrGsam\.  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant V9:h4]  
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    '************************************************************************* .".xNHR#  
    'Radius and conic constant of posterior lens 'Ldlo+*|5  
    '************************************************************************* \de824  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ZyBNo]  
    GetConic eID, entity, curv, conic 2QUZAV\ Y  
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    SetConic eID, entity, 1/Rpost, CCpost Is~bA_- ;  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost p?OwcMT]M  
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    '************************************************************************* mOj6 4}_`"  
    'Lens thickness (Position of posterior lens surface) 8U8l 5r  
    '************************************************************************* VXforI  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) T<*i($ [  
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    ' Delete any z-shift(s) Py$*c  
    count = 0 2.=3:q!H<%  
    While GetOperationCount(eID)>count @\ip?=  
        GetOperation eID, count, op =4z:Df  
        If op.Type="ShiftZ" Then KsM2?aqwf_  
            DeleteOperation eID,count S$q:hXZ#e  
            count=count-1 g:/l5~b  
        End If .aWEXJ  
        count=count+1 sidSY8j  
    Wend ' bio:1  
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    'Set new z-shift ^E&':6(  
    op.Type = "ShiftZ" ShAI6j  
    op.val1 = tlens eR.ucTji  
    op.parent = parID MIPmsEdBi  
    AddOperation eID, op Yr@)W~  
    Print "Set lens thickness = " & tlens >jjuWO3T  
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    '************************************************************************* /[YH W]  
    'Lens index of refraction T)B
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    '************************************************************************* ^|DI9G(Bs  
    eID = FindMaterial( "Lens" ) tp2CMJc{L  
    GetModelMaterial eID, mat {l=!  
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    mat.Nd = nlens "WOY`su>  
    SetModelMaterial eID, mat CLI!(8ZW  
    Print "Set lens index of refraction = " & nlens o.DT`L8  
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    '************************************************************************* pX ]K-  
    'Pupil diameter s$e0;C!D  
    '************************************************************************* U@v=q9'W  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) x0wy3+GZc  
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    'Adjust pupil diameter (trimming volume inner hole) cF_hU"  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" w~>V2u_-  
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    ' Adjust pupil location to just in front of the lens jj8AV lN  
    parID = FindFullName( "Geometry.Arizona Eye" ) ot P7;l  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) _@0>yMZ^  
    count = 0 T!eb=oy  
    While GetOperationCount(eID)>count j;eR9jI$T  
        GetOperation eID, count, op z8+3/jLN0B  
        If op.Type="ShiftZ" Then qy6zHw  
            DeleteOperation eID,count NZ`W`#{  
            count=count-1 u= ( kii=/  
        End If HgY"nrogt$  
        count=count+1 )|f!}( p  
    Wend @~Z:W<X  
    op.Type = "ShiftZ" A<.`HCv2  
    op.val1 = taq-0.01 jvn:W{'Q  
    op.parent = parID }~$zdgMT  
    AddOperation eID, op uNV(r"
 
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    Print "Set pupil diameter = " & pupilDiam 
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    'Update AZ Eye subassembly Description FQSepUl  
    eID = FindFullName( "Geometry.Arizona Eye" ) Kr`Cr5v  
    GetEntity eID, entity B@dA?w.x  
    entity.Description = "Accommodation = " & A & "D" cMxTv4|wui  
    SetEntity eID, entity *b9=&:pU(  
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    Update T:S+Pt~  
    Print "DONE!" U.UN=uv_  
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End Sub +K2jYgy  
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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： xS]=WO*  
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Accommodation = 4 Diopters =rcqYPul0  
Pupil Diameter = 4 mm ai[st+1  
Set aqueous humor thickness = 2.81 4Y8/>uL  
Set anterior lens radius = 10.4 and conic constant = -2.375869 /,A:HM>B  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 rWEJCFa  
Set lens thickness = 3.927 EXUjdJs"  
Set lens index of refraction = 1.42672 iqURlI);P  
Set pupil diameter = 4 ziCTvT  
DONE! jI!}}K)d