[分享]Arizona眼睛模型 [复制链接]

简介 Q2iS0#  
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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。 *[(O&L&0  
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模型 wX" 6 S:  
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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。 xxgS!J  
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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. .{LFc|Z[  
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光源 IL?3>$,  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 7^#f<m;Ar!  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 4:=']C  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 hS}?"ST|  
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视网膜的散射 nVko]y  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 >xws  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 q3adhY9|)0  
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脚本 j|TcmZGO  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： wd2GKq!  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 bO>q`%&  
余下的脚本计算与屈光度有关的所有参数。 a,tzt ]>  
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分析 IL`X}=L_  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 2jV.\
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脚本代码 c[J(H,mt/  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. h3D~?Iom  
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Dim entity As T_ENTITY bD*V$w*P  
Dim op As T_OPERATION YyEW}2  
Dim mat As T_MODELMATERIAL m/RX~,T*v&  
Dim A As Double S7]\tw_L)  
Dim pupilDiam As Double Jn3cU  
Dim eID As Long Z&9MtpC+N3  
Dim parID As Long 8}z]B^?Fy  
Dim count As Integer huFT_z_;;  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double f#mBMdj  
Dim tlens As Double, nlens As Double ef8_w6i  
Dim curv As Double, conic As Double 
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Dim ok As Long yW5/Y02  
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Sub Main )Be?axI  
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    '用户输入对话框 !=%0  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 &J(+X
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        TextBox 220,21,40,21,.TextBox1 'default: 0 IlQNo 1  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 X^;[X~
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        OKButton 40,91,90,21 ^'>kZ^w0  
        CancelButton 190,91,90,21 6Y?%G>$6  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 l3kYfq{";"  
        TextBox 220,49,40,21,.TextBox2 'default: 4 eD5:0;X2  
    End Dialog WeyH;P=  
    Dim dlg As UserDialog "c5C0 pK0  
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    ok = Dialog (dlg) !kCMw%[  
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    If ok=0 Then    'cancel button was pressed Tk~RT<\Ab+  
        Print "Execution cancelled." b{Srd3  
        End xS.Rpx/8  
    End If vxuxfi8x  
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    'Assign accommodation and pupil diameter & use defaults if field left empty pkTg.70wU  
    If dlg.TextBox1 = "" Then YDh6XD<Z  
        A = 0           'Default accommodation OSP#FjH  
    Else 8/q6vk><  
        A = CDbl(dlg.TextBox1) oVi_X98R  
    End If OS|uZ<"Rq3  
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    If dlg.TextBox2 = "" Then 1$S;
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        pupilDiam = 4   'Default pupil diameter S}fU2Wi  
    Else xX;@ BS  
        pupilDiam = CDbl(dlg.TextBox2) i>=d7'oR  
    End If 9gjI;*(z1  
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    Print " " @ qFE6!  
    Print "Accommodation = " & A & " Diopters" cfZG3"  
    Print "Pupil Diameter = " & pupilDiam & " mm" /P_1vQq  
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    ' Calculate new parameters with accommodation yWS#{|o(  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness H<tk/\C  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens }m '= _u  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens g~q+a-  

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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens e<_yr>9g"  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens \Xy]z  
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    tlens = 3.767 + 0.04*A                  'Lens thickness nq'vq]]  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction "v.]s;g  
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    'Adjust parameters to account for accommodation q\ihye  
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    '************************************************************************* iC U[X&  
    'Aqueous thickness (Position of Lens) JGmW>mH  
    '************************************************************************* WW.\5kBl8  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) [w iI  
    GetCustomElement eID, entity q;I`&JK  
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    parID = FindFullName( "Geometry.Arizona Eye" ) o;#{N~4[$  
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    ' Delete any shift(s) in z qF9rY)ifm  
    count = 0 K?l1Gj  
    While GetOperationCount(eID)>count WA);Z=  
        GetOperation eID, count, op 9&'I?D&8  
        If op.Type="ShiftZ" Then *q5'~)W<  
            DeleteOperation eID,count E\M{/.4 4  
            count=count-1 rWN#QL()*  
        End If Bx(+uNQ  
        count=count+1 )9,*s!)9  
    Wend dhW;|  
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    'Set new shift in wu*WA;FnA  
    op.Type = "ShiftZ" 3t(8uG<rL  
    op.val1 = taq X,- ' v[z  
    op.parent = parID dEXHd@"H  
    AddOperation eID, op cz_4cMgxu  
    Print "Set aqueous humor thickness = " & taq-0.55 qZ!1>`B  
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    '************************************************************************* T[$Sbz`  
    'Radius and conic constant of anterior lens (xU+Y1*g"%  
    '************************************************************************* D\Y)E#%,  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Isq3YY  
    GetConic eID, entity, curv, conic FswMEf-|  
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    SetConic eID, entity, 1/Rant, CCant mB(*)PwZ  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant CvpqQ7&k7  
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    '************************************************************************* >l$vu-k)~4  
    'Radius and conic constant of posterior lens PVO9KWv**  
    '************************************************************************* $,k SR}  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ;(w=}s%]+  
    GetConic eID, entity, curv, conic hp(n;(OR  
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    SetConic eID, entity, 1/Rpost, CCpost K{VF_S:  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost !DnG)4#  
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    '************************************************************************* f{e*R#+&  
    'Lens thickness (Position of posterior lens surface) @ ADY?  
    '************************************************************************* D} 0>x~  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 
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    ' Delete any z-shift(s) b*Ipg8n+  
    count = 0 ?Di
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    While GetOperationCount(eID)>count 81a&99k#  
        GetOperation eID, count, op Y=G *[
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        If op.Type="ShiftZ" Then /2u;w!oi.  
            DeleteOperation eID,count f/)3b`$Wu  
            count=count-1 AW'tZF"  
        End If Coq0Kzhsab  
        count=count+1 ZP)=2'RY  
    Wend Tu_dkif'  
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    'Set new z-shift }jd[>zk  
    op.Type = "ShiftZ" s)=L6t^a6  
    op.val1 = tlens v%3)wD  
    op.parent = parID :kZ2N67  
    AddOperation eID, op kSNVI-Wzu  
    Print "Set lens thickness = " & tlens ?l,i(I  
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    '************************************************************************* iy tSC  
    'Lens index of refraction ]CC= \<  
    '************************************************************************* hl~(&D1^  
    eID = FindMaterial( "Lens" ) 9r1pdG_C@  
    GetModelMaterial eID, mat -lL*
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    mat.Nd = nlens 
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    SetModelMaterial eID, mat Op3 IL/  
    Print "Set lens index of refraction = " & nlens z,rWj][P  
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    '************************************************************************* jZv8X5
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    'Pupil diameter 4BEVG&Ks  
    '************************************************************************* @YwaOc_%  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" )
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    'Adjust pupil diameter (trimming volume inner hole) XQ(`8Jl&^  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" hQGZrZK#  
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    ' Adjust pupil location to just in front of the lens M`?/QU~  
    parID = FindFullName( "Geometry.Arizona Eye" ) mA^>Y_:  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) PLLlo~Bb  
    count = 0 /HzhgMV3  
    While GetOperationCount(eID)>count YSrFHVq  
        GetOperation eID, count, op l}Xmm^@)  
        If op.Type="ShiftZ" Then `MTOe1  
            DeleteOperation eID,count !y] Y'j  
            count=count-1 5 (H; x74  
        End If McsqMI6  
        count=count+1 b!.# `.  
    Wend /@#)j( eY/  
    op.Type = "ShiftZ" 6AQ;P  
    op.val1 = taq-0.01 g"Ii'JZ?  
    op.parent = parID *R~oA`
 
    AddOperation eID, op "\_}"0H  
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    Print "Set pupil diameter = " & pupilDiam Y"l!3^  
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    'Update AZ Eye subassembly Description 8%xtb6#7M  
    eID = FindFullName( "Geometry.Arizona Eye" ) zV80r+y  
    GetEntity eID, entity v>R.M"f  
    entity.Description = "Accommodation = " & A & "D" A`N;vq,  
    SetEntity eID, entity ]`4QJ;#  
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    Update r*p%e\ 3  
    Print "DONE!" 3:;%@4f  
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End Sub l%w7N9  
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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： c//W#V2Q  
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Accommodation = 4 Diopters 8v6rS-iHP  
Pupil Diameter = 4 mm 57MoO  
Set aqueous humor thickness = 2.81 !<X_XA  
Set anterior lens radius = 10.4 and conic constant = -2.375869 1b!l+ 8!  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 WI~%n  
Set lens thickness = 3.927 Ol-'2l  
Set lens index of refraction = 1.42672 &1u?W%(Px  
Set pupil diameter = 4
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DONE! cXCczqabv  
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