[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。 NUO#[7OK+x  
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模型 kAV4V;ydh  
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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。
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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. ^;
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光源 *x!j:/S`n  
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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。 ]F{F+r  
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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。 "lVbla4b  
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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。 iFOa9!_0n  
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视网膜的散射 9GX'+$R]  
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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。 aCRiW;+'  
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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。 $jg~a  
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脚本 t`- [  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： mIe 5{.m#  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 8 \"A-+_Q  
余下的脚本计算与屈光度有关的所有参数。 (j(hr'f  
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分析 e +Ikw1y"f  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 a"{b}UP  
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脚本代码 )GfL?'Z  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. mKLWz1GZ  
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Dim entity As T_ENTITY m f\tMik<  
Dim op As T_OPERATION k5|GN Y6a  
Dim mat As T_MODELMATERIAL qL?$u07<9'  
Dim A As Double gg.lajX  
Dim pupilDiam As Double BZa`:ah~x  
Dim eID As Long -bgj<4R$p  
Dim parID As Long ]*X z~Ox2  
Dim count As Integer J^=Xy(3e  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ?@^gpVK{  
Dim tlens As Double, nlens As Double :(K JLa]  
Dim curv As Double, conic As Double  w!b;.l  
Dim ok As Long R
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Sub Main v\g1w&PN  
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    '用户输入对话框 oT!i}TW?o  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 !TN)6e7`  
        TextBox 220,21,40,21,.TextBox1 'default: 0 Ekn3ODz,  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 "[sr0'g:  
        OKButton 40,91,90,21 sVH w\_F$  
        CancelButton 190,91,90,21 6H!l>@a7v  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 6n\){dkZ~  
        TextBox 220,49,40,21,.TextBox2 'default: 4 F9>"1  
    End Dialog xS;tmc  
    Dim dlg As UserDialog y~z&8XrH  
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    ok = Dialog (dlg) ^SbxClUfw!  
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    If ok=0 Then    'cancel button was pressed E;YD5^B  
        Print "Execution cancelled." wjTW{Bg~G  
        End RSx{Gbd4X  
    End If 4j(*%da  
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    'Assign accommodation and pupil diameter & use defaults if field left empty mln%Rd6u/  
    If dlg.TextBox1 = "" Then B}@CtVWFz  
        A = 0           'Default accommodation R ^"*ut  
    Else #+ {%>f  
        A = CDbl(dlg.TextBox1) Knp}88DR^j  
    End If Q6p75$SVq  
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    If dlg.TextBox2 = "" Then EL6<%~,V"I  
        pupilDiam = 4   'Default pupil diameter #dFE}!"#`  
    Else t1p[!53(  
        pupilDiam = CDbl(dlg.TextBox2) 2gW+&5;4  
    End If id)J;!^;J  
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    Print " " [7l5p(=  
    Print "Accommodation = " & A & " Diopters" k;<F33v;Mh  
    Print "Pupil Diameter = " & pupilDiam & " mm" ;+n25_9  
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    ' Calculate new parameters with accommodation )o;n2T#O  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 6?-,@e  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens XcKyrh;i  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ,w,)n^  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ;(s.G-9S  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 3=_to7]  
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    tlens = 3.767 + 0.04*A                  'Lens thickness rUmnv%qTS  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction R7Ns5s3X  
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    'Adjust parameters to account for accommodation _<jccQ  
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    '************************************************************************* nz`"f,  
    'Aqueous thickness (Position of Lens) Y|<1|wG
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    '************************************************************************* h=_h,?_  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 2'WdH1UrBc  
    GetCustomElement eID, entity tp b(.`G  
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    parID = FindFullName( "Geometry.Arizona Eye" ) BgwZZ<B  
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    ' Delete any shift(s) in z #Y>d@  
    count = 0 S4%MnT6Uy  
    While GetOperationCount(eID)>count BtP*R,>  
        GetOperation eID, count, op cKAZWON8;v  
        If op.Type="ShiftZ" Then 9R|B 5.  
            DeleteOperation eID,count 0.!Q4bhD  
            count=count-1 (d-j/v*4  
        End If SFa^$w  
        count=count+1 "Oy&6rrr  
    Wend "#`c\JuR]  
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    'Set new shift in |y2cI,&  
    op.Type = "ShiftZ" .w)T2(  
    op.val1 = taq B'D4]EB  
    op.parent = parID  \4&FW|mx  
    AddOperation eID, op EB>rY  
    Print "Set aqueous humor thickness = " & taq-0.55 %suXp,j  
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    '************************************************************************* |p+ xM  
    'Radius and conic constant of anterior lens ,_yf5 a  
    '************************************************************************* Jx= v6==7  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) wB W]w  
    GetConic eID, entity, curv, conic V~qlg1h  
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    SetConic eID, entity, 1/Rant, CCant pi?U|&.1z  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant <S M%M?  
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    '************************************************************************* XWFuAE  
    'Radius and conic constant of posterior lens W>]=0u4  
    '************************************************************************* &:*|K
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) [KjL`  
    GetConic eID, entity, curv, conic Oo95\Yf$N  
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    SetConic eID, entity, 1/Rpost, CCpost eEkbD"Q  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost -* ;`~5  
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    '************************************************************************* @Y2&v956  
    'Lens thickness (Position of posterior lens surface) ni x1_Wo;  
    '************************************************************************* \muC_9ke  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) EJ3R{^  
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    ' Delete any z-shift(s) .%EEly  
    count = 0 t Sf`  
    While GetOperationCount(eID)>count B%Spmx
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        GetOperation eID, count, op (eAh8^)  
        If op.Type="ShiftZ" Then gRdg3qvU  
            DeleteOperation eID,count .4wp  
            count=count-1 ROHr%'owgL  
        End If Wc)f:]7  
        count=count+1 8o;9=.<<~u  
    Wend nfMQ3KP  
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    'Set new z-shift K r&HT,>B  
    op.Type = "ShiftZ" H A(e  
    op.val1 = tlens Xpd^^  
    op.parent = parID =1"8
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    AddOperation eID, op Y-WYQ{  
    Print "Set lens thickness = " & tlens l`R/
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    '************************************************************************* xFY;aK  
    'Lens index of refraction A@0%7xm  
    '************************************************************************* V/G'{ q  
    eID = FindMaterial( "Lens" ) lS(?x
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    GetModelMaterial eID, mat }9xEA[@;  
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    mat.Nd = nlens :d<;h:^_  
    SetModelMaterial eID, mat `MtPua\_  
    Print "Set lens index of refraction = " & nlens }X3SjNd q  
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    '************************************************************************* 2|)3Ly9  
    'Pupil diameter Osdw\NNH~M  
    '************************************************************************* aMFUJrXo
 
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) D`lTP(] y  
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    'Adjust pupil diameter (trimming volume inner hole) lc=C  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ~Cj55S+  
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    ' Adjust pupil location to just in front of the lens gHC -Y 0_  
    parID = FindFullName( "Geometry.Arizona Eye" ) |Y!#`  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Fr)G h>  
    count = 0 MX?K3=j @>  
    While GetOperationCount(eID)>count s45Y8!c  
        GetOperation eID, count, op P.RlozF5;  
        If op.Type="ShiftZ" Then }xHoitOD  
            DeleteOperation eID,count _{o=I?+]  
            count=count-1 B8_w3;x  
        End If *Ri?mEv hF  
        count=count+1 .Mw'P\GtM  
    Wend p IXBJk  
    op.Type = "ShiftZ" 9LGJ-gL  
    op.val1 = taq-0.01
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    op.parent = parID OedL?4  
    AddOperation eID, op DA@YjebP'  
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    Print "Set pupil diameter = " & pupilDiam 4?X#d)L(  
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    'Update AZ Eye subassembly Description Te~"\`omJ3  
    eID = FindFullName( "Geometry.Arizona Eye" ) {
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    GetEntity eID, entity 
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    entity.Description = "Accommodation = " & A & "D" X|H%jdta  
    SetEntity eID, entity gO?+:}!  
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    Update d+%1q
 
    Print "DONE!" j[yGfDb  
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End Sub SHPaSq'
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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： -
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Accommodation = 4 Diopters wYhWR
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Pupil Diameter = 4 mm *~fZ9EkD  
Set aqueous humor thickness = 2.81 %FQMB  
Set anterior lens radius = 10.4 and conic constant = -2.375869 >/EmC3?b!  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 /g712\?M4  
Set lens thickness = 3.927 'bkecC  
Set lens index of refraction = 1.42672 ,-t3gc1~X  
Set pupil diameter = 4 Y*O7lZuF%  
DONE! XZA3TZ