[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 Rcuz(yS8  
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。 [Xkx_B  
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模型 OUnA;_  
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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。 F9^S"qv$  
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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. CIWO7bS
 
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光源 NEs:},)o  
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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。 5P bW[  
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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。 jXJyc'm7  
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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。 T{"(\X$  
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视网膜的散射 +T ?NH9  
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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。 y_,bu^+*  
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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。 e20-h3h+  
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脚本 b>k y  
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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： A&{Nh` q
 
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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。 iso4]>LF  
余下的脚本计算与屈光度有关的所有参数。 Xj*Wu_  
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分析 iLT}oKF2N;  
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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。 0:+E-^X  
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脚本代码 B!yr!DW
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. V]&\fk-{  
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Dim entity As T_ENTITY m|# y >4  
Dim op As T_OPERATION n%-0V>  
Dim mat As T_MODELMATERIAL ?"FbsMk.d  
Dim A As Double .hiSw  
Dim pupilDiam As Double tkhCw/  
Dim eID As Long ;jPXs  
Dim parID As Long VL^EHb7  
Dim count As Integer +(*DT9s+  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double DlT{`  
Dim tlens As Double, nlens As Double *"kM{*3:v  
Dim curv As Double, conic As Double H]!"Zq k  
Dim ok As Long h![#;>(  
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Sub Main ^{{qV  
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    '用户输入对话框 Qd6FH2Pl  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 _m>b2I?  
        TextBox 220,21,40,21,.TextBox1 'default: 0 g>sSS8RO  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 zQA`/&=Y  
        OKButton 40,91,90,21 Je@v8{][|  
        CancelButton 190,91,90,21 07)yG:q*x  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 }Lv;

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        TextBox 220,49,40,21,.TextBox2 'default: 4 8Y3I0S  
    End Dialog 5r_|yu  
    Dim dlg As UserDialog _
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    ok = Dialog (dlg) $cR{o#  
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    If ok=0 Then    'cancel button was pressed :LTN!jj  
        Print "Execution cancelled." KG@8RtHsQ  
        End V1?]|HTQcT  
    End If zJXplvaL;  
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    'Assign accommodation and pupil diameter & use defaults if field left empty {t!!Uz 7  
    If dlg.TextBox1 = "" Then *kVV+H<X|b  
        A = 0           'Default accommodation AEuG v}#  
    Else q =Il|Nb>  
        A = CDbl(dlg.TextBox1) ]~%6JJN7  
    End If ^&)|sP  
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    If dlg.TextBox2 = "" Then >MK98(F  
        pupilDiam = 4   'Default pupil diameter ]{kPrey  
    Else 
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        pupilDiam = CDbl(dlg.TextBox2) 6Iw\c  
    End If .KC++\{HE  
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    Print " " r
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    Print "Accommodation = " & A & " Diopters" 8] ikygt"  
    Print "Pupil Diameter = " & pupilDiam & " mm" aP`P)3O6)1  
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    ' Calculate new parameters with accommodation 7Qsgys#/=  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 5coZ|O&f8  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens GF WA>5n'  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens smLQS+UE  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens tu?MYp;
  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Df#l8YK#  
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    tlens = 3.767 + 0.04*A                  'Lens thickness PVOv[%  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ETLD$=iS  
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    'Adjust parameters to account for accommodation kW (B
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    '************************************************************************* yEoV[K8k  
    'Aqueous thickness (Position of Lens) 2"5v[,$1H  
    '************************************************************************* ty`DJO=Omj  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) tl].r|yl  
    GetCustomElement eID, entity BB'OCN  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 6R5Qy]]E  
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    ' Delete any shift(s) in z Wm3X[?V  
    count = 0 d/Q%IeEL.  
    While GetOperationCount(eID)>count yWya&|D9  
        GetOperation eID, count, op F>cv<l =6l  
        If op.Type="ShiftZ" Then X76e&~  
            DeleteOperation eID,count /=, nGk>  
            count=count-1 HKr Mim-  
        End If @R  6@]Dm  
        count=count+1 Lxk[;j+  
    Wend e$pV%5=  
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    'Set new shift in L:
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    op.Type = "ShiftZ" W];dD$Oqg  
    op.val1 = taq V!dtF,tH  
    op.parent = parID &I406Z f7y  
    AddOperation eID, op `#gie$B{  
    Print "Set aqueous humor thickness = " & taq-0.55 WT}H

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    '************************************************************************* YDFyX){  
    'Radius and conic constant of anterior lens ,1##p77.  
    '************************************************************************* l\?c}7k  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) OC:T O|S:4  
    GetConic eID, entity, curv, conic _,d~}_$`i  
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    SetConic eID, entity, 1/Rant, CCant VYhbx 'e  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant !3v1bGk  
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    '************************************************************************* Z:7fV5b(  
    'Radius and conic constant of posterior lens O<e{  
    '************************************************************************* 6u}</>}  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ;Q&5,< N)j  
    GetConic eID, entity, curv, conic Y5d\d\e/  
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    SetConic eID, entity, 1/Rpost, CCpost GDy9qUV  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost \r>6`-cs]  
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    '************************************************************************* Y]5l.SV  
    'Lens thickness (Position of posterior lens surface)  v<:R#  
    '************************************************************************* 0{[,E.  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) F*K_+ ?m  
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    ' Delete any z-shift(s) zNuJjL  
    count = 0 =6#Eh=7N  
    While GetOperationCount(eID)>count Z87|Zl  
        GetOperation eID, count, op f>Jr|#k  
        If op.Type="ShiftZ" Then I,'
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            DeleteOperation eID,count !7&5` q7  
            count=count-1 ivz5H(b  
        End If m<g~H4  
        count=count+1 o\)F}j&b#=  
    Wend O5t[  
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    'Set new z-shift XEZF{lP  
    op.Type = "ShiftZ" _H=Uwi_g  
    op.val1 = tlens g SAt@2*U2  
    op.parent = parID BIWWMg  
    AddOperation eID, op 5-xX8-ElYz  
    Print "Set lens thickness = " & tlens xpx\=iAe  
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    '************************************************************************* QZ%`/\(!8_  
    'Lens index of refraction D+7Rz_=  
    '************************************************************************* 'anG:=  
    eID = FindMaterial( "Lens" ) ?#YE`]  
    GetModelMaterial eID, mat 5j-YM  
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    mat.Nd = nlens R#8L\1l  
    SetModelMaterial eID, mat M_w<m  
    Print "Set lens index of refraction = " & nlens t\j*}# S  
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    '************************************************************************* JO"<{ngsQ  
    'Pupil diameter Q7COQ2~K   
    '************************************************************************* l/ ;  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) fn6J*[`  
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    'Adjust pupil diameter (trimming volume inner hole) SrK<fAkx  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" g]yBA7/S"  
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    ' Adjust pupil location to just in front of the lens qXtC^n@x  
    parID = FindFullName( "Geometry.Arizona Eye" ) %(G* ,  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) &&RimoIeo  
    count = 0 f\>M'{cV  
    While GetOperationCount(eID)>count =;&yd';k  
        GetOperation eID, count, op M$8^9
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        If op.Type="ShiftZ" Then 6,9>g0y'NG  
            DeleteOperation eID,count ^7KH _t8
 
            count=count-1 X~,aNRy  
        End If r7,t";?>  
        count=count+1 LRG6
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    Wend Yv!a88+A8M  
    op.Type = "ShiftZ" e?=^;v%r  
    op.val1 = taq-0.01 #PQB(=299P  
    op.parent = parID #@~+HC=  
    AddOperation eID, op O,h;hQZ  
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    Print "Set pupil diameter = " & pupilDiam Zt.|oYH$  
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    'Update AZ Eye subassembly Description 6N S201o  
    eID = FindFullName( "Geometry.Arizona Eye" ) -f>%+<k=  
    GetEntity eID, entity o;R2p $  
    entity.Description = "Accommodation = " & A & "D" JU5C}%Q6  
    SetEntity eID, entity Nyj( 0W  
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    Update iBgx  
    Print "DONE!" .KUv(-  
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End Sub &&:YVd  
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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： \\dMy9M-  
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Accommodation = 4 Diopters 04l!:Tp,  
Pupil Diameter = 4 mm 9!}8UALD  
Set aqueous humor thickness = 2.81 8tFoN*M  
Set anterior lens radius = 10.4 and conic constant = -2.375869 emPM4iG?!  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 0dhaAq`k  
Set lens thickness = 3.927 iJ3e1w$  
Set lens index of refraction = 1.42672 .1Al<OLL  
Set pupil diameter = 4 YLv'43PL  
DONE! tL)t"  i  
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