[分享]Arizona眼睛模型 [复制链接]

简介 VrG4wLpLs  
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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。 [s1Hd~$  
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模型 [h"#Gwb=;  
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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。 1-z*'Ghys  
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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. X`,4pSQ;  
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光源 G'|Emu=4  
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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。 [w iI  
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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。 D+ki2UVt&  
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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。 @G/':N   
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视网膜的散射 ,+p&ZpH
 
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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。 dhW;|  
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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。 5io7!%  
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脚本 ?FRR";  
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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： ivdw1g|)h  
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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。 -`e=u<Y9@  
余下的脚本计算与屈光度有关的所有参数。 `92 D]^g  
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分析 ,5\:\e0H  
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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。 ~L(_q]  
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脚本代码 [5%/{W,~m  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. ]\nG1+ta  
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Dim entity As T_ENTITY !2x"'o  
Dim op As T_OPERATION #
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Dim mat As T_MODELMATERIAL ^_<>o[qE  
Dim A As Double x7e  
Dim pupilDiam As Double </y V  
Dim eID As Long rL URP2~  
Dim parID As Long PiB)pUYj  
Dim count As Integer *f8,R"]-g  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double +N[dYm  
Dim tlens As Double, nlens As Double MW9B -x  
Dim curv As Double, conic As Double ej,MmLu~^  
Dim ok As Long [
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Sub Main 4x'^?0H@  
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    '用户输入对话框 2W pe( \(  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Y,D\_il_  
        TextBox 220,21,40,21,.TextBox1 'default: 0 )<.S3  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ?HIc=  
        OKButton 40,91,90,21 pmCBe6n\l  
        CancelButton 190,91,90,21 kt1f2cj  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ;lGa.RD[a  
        TextBox 220,49,40,21,.TextBox2 'default: 4 p!'
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    End Dialog se_zCS4Y  
    Dim dlg As UserDialog +bm2vIh$  
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    ok = Dialog (dlg) :&)RK~1m_  
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    If ok=0 Then    'cancel button was pressed 5d}PrYa  
        Print "Execution cancelled." E08AZOY&g  
        End dab>@z4  
    End If 3:Co K#  
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    'Assign accommodation and pupil diameter & use defaults if field left empty |ry;'[*  
    If dlg.TextBox1 = "" Then Cw{#(x
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        A = 0           'Default accommodation jo<sN  
    Else 2|}p&~G(  
        A = CDbl(dlg.TextBox1) Q\=u2}/z0  
    End If D~f.)kkC4  
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    If dlg.TextBox2 = "" Then MPzqw)_-v  
        pupilDiam = 4   'Default pupil diameter rvE!Q=y~  
    Else N#.IpY'7Ze  
        pupilDiam = CDbl(dlg.TextBox2) ;JL@V}L,  
    End If \f66ipZK*  
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    Print " " =As'vt 0  
    Print "Accommodation = " & A & " Diopters" flLmZ1"  
    Print "Pupil Diameter = " & pupilDiam & " mm" 0^
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    ' Calculate new parameters with accommodation xC;$/u%'  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness TaolX*$5  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens i0AC.]4e"  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens O1#rCFC|y  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens %oor7 -l  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens DBmcvC  
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    tlens = 3.767 + 0.04*A                  'Lens thickness 609=o+  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction |e< U%v  
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    'Adjust parameters to account for accommodation >a4Bfnf"eI  
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    '************************************************************************* 1~`gfHI4  
    'Aqueous thickness (Position of Lens) ]hf4= gm  
    '************************************************************************* w@:o:yLS  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) PPq*_Cf  
    GetCustomElement eID, entity 2PeI+!7s  
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    parID = FindFullName( "Geometry.Arizona Eye" ) .`h+fqa  
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    ' Delete any shift(s) in z 41uSr 1  
    count = 0 @pS[_!EqYz  
    While GetOperationCount(eID)>count (/KF;J^M  
        GetOperation eID, count, op mMjVbeh[  
        If op.Type="ShiftZ" Then }E1Eq
  
            DeleteOperation eID,count v'@LuF'e8  
            count=count-1 7I44BC*R~  
        End If ah<f&2f  
        count=count+1 Rw\DJJrz  
    Wend L+kS8D<  
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    'Set new shift in =H?Nb:s  
    op.Type = "ShiftZ" qnm9Lw#  
    op.val1 = taq G7=8*@q>:  
    op.parent = parID C9iG`?  
    AddOperation eID, op ``z="oD  
    Print "Set aqueous humor thickness = " & taq-0.55 kg@J.  
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    '************************************************************************* HZ}'W<N  
    'Radius and conic constant of anterior lens uA,{C%?  
    '************************************************************************* H5%I?ZXw4  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Q$zlxn 7\  
    GetConic eID, entity, curv, conic Z)&HqqT3p  
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    SetConic eID, entity, 1/Rant, CCant HWU{521  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant DtS{iH=s]  
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    '************************************************************************* ?d0Dfqh_  
    'Radius and conic constant of posterior lens ;Dgp !*v=  
    '************************************************************************* 0q;] ;m  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) "|%fAE  
    GetConic eID, entity, curv, conic ;5l|-&{@*  
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    SetConic eID, entity, 1/Rpost, CCpost O^$Zz<  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost #e=^-yE  
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    '************************************************************************* LYFvzw>M  
    'Lens thickness (Position of posterior lens surface) y$"L`*W  
    '************************************************************************* Ol@ZH_  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) /W>"G1)  
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    ' Delete any z-shift(s) 0Q9OQqg m  
    count = 0 ~>R)H#mP7  
    While GetOperationCount(eID)>count 2fk   
        GetOperation eID, count, op b#U%aPH  
        If op.Type="ShiftZ" Then c 1GP3
 
            DeleteOperation eID,count A~>=l=  
            count=count-1 `
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        End If E=QQZ\w  
        count=count+1 'W*F[U*&HP  
    Wend ]>o2P cb;  
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    'Set new z-shift B=r/(
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    op.Type = "ShiftZ" ?rDwYG(u]@  
    op.val1 = tlens y^rg%RV  
    op.parent = parID jayoARUB  
    AddOperation eID, op :[39g;V}c  
    Print "Set lens thickness = " & tlens ?0a 0 R  
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    '************************************************************************* *ZGN!0/  
    'Lens index of refraction hzb|:  
    '************************************************************************* $C/Gn~k 5  
    eID = FindMaterial( "Lens" ) S@)bl  
    GetModelMaterial eID, mat }"Cn kg  
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    mat.Nd = nlens nE;gM1I  
    SetModelMaterial eID, mat 6f!mk:\T.  
    Print "Set lens index of refraction = " & nlens h_L '_*  
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    '************************************************************************* bl<7[J.  
    'Pupil diameter &/F
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    '************************************************************************* c,wU?8Nc|$  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ^aCYh[
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    'Adjust pupil diameter (trimming volume inner hole) ]Dg0@Y  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ?g4|EV-56  
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    ' Adjust pupil location to just in front of the lens ^nF$<#a  
    parID = FindFullName( "Geometry.Arizona Eye" ) BkfBFUDQ  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) :nUsC+oBS  
    count = 0 ]:s|.C%qI  
    While GetOperationCount(eID)>count Nk4_!  
        GetOperation eID, count, op |plo65  
        If op.Type="ShiftZ" Then I+t38un%  
            DeleteOperation eID,count ,?6m"ov4(  
            count=count-1 ""^BW Re D  
        End If }8: -I Nj4  
        count=count+1 q?4uH;h:^G  
    Wend e~;)-Z  
    op.Type = "ShiftZ" n
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    op.val1 = taq-0.01 HPKyAcS\  
    op.parent = parID
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    AddOperation eID, op Zr;=p"cXr  
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    Print "Set pupil diameter = " & pupilDiam 66^t[[  
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    'Update AZ Eye subassembly Description z{L;)U B^  
    eID = FindFullName( "Geometry.Arizona Eye" ) nF$)F?||  
    GetEntity eID, entity b.*4RL  
    entity.Description = "Accommodation = " & A & "D" E}/|Lja  
    SetEntity eID, entity [frD L)  
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    Update UO<claV  
    Print "DONE!" 2
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End Sub F$p*G][  
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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： no6]{qn=6  
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Accommodation = 4 Diopters &"%|`gE  
Pupil Diameter = 4 mm <# r.}T.l  
Set aqueous humor thickness = 2.81 <" l;l~Y1  
Set anterior lens radius = 10.4 and conic constant = -2.375869 Yj/nzTVJ[  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 uN3J)@;_  
Set lens thickness = 3.927 1|w:xG^  
Set lens index of refraction = 1.42672 'OW"*b  
Set pupil diameter = 4 %P,^}h7  
DONE! $!!=fFX*y  
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