[分享]Arizona眼睛模型 [复制链接]

简介 rgv?gaQ>  
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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。 KVaiugQ  
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模型 EIAc@$4  
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模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 t!X.|`h  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. b<ZIWfs  
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光源 JPUW6e07o  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 }W8;=$jr  
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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。 o4,6.1}  
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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。 o5GcpbZ3k  
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视网膜的散射 9
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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。 NB#OCH1/9  
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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。 L}b.ulkMD  
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脚本 iy!=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： lNh70G8^p  
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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。
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余下的脚本计算与屈光度有关的所有参数。 -3*]G^y2  
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分析 ED( Sg  
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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。 !i}w~U<  
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脚本代码 BwpqNQN  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used.  4e7-0}0  
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Dim entity As T_ENTITY \?-<4Bc@  
Dim op As T_OPERATION V)k4:H  
Dim mat As T_MODELMATERIAL o5PO=AN  
Dim A As Double Q&tG4f<  
Dim pupilDiam As Double lrE5^;/s1  
Dim eID As Long l|[N42+  
Dim parID As Long Of#u  
Dim count As Integer h7oo7AP  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ^uc=f2=>,  
Dim tlens As Double, nlens As Double eM6<%?b  
Dim curv As Double, conic As Double SKN`2hD  
Dim ok As Long i1d'nxk6  
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Sub Main &Z@o Q
 
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    '用户输入对话框 +\]\[6  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1  8dA~\a  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ,ZNq,$j  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 oZgjQM$YP  
        OKButton 40,91,90,21 <n$'voR7]  
        CancelButton 190,91,90,21 Z5n1@a__  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ?l{nk5,?-Y  
        TextBox 220,49,40,21,.TextBox2 'default: 4 rs[T=CQ  
    End Dialog M|h3Wt~7  
    Dim dlg As UserDialog %sP*=5?vA  
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    ok = Dialog (dlg) (ZZ8L-s  
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    If ok=0 Then    'cancel button was pressed _TZRVa_  
        Print "Execution cancelled." .`eN8Dl1  
        End \}b%E'+_T  
    End If dZ
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    'Assign accommodation and pupil diameter & use defaults if field left empty 7JH6A'&  
    If dlg.TextBox1 = "" Then ~<bZ1TD   
        A = 0           'Default accommodation wn%A4-%{  
    Else $6 f3F?y7  
        A = CDbl(dlg.TextBox1) UiW>J  
    End If H7n>Vx:L-  
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    If dlg.TextBox2 = "" Then rb.N~  
        pupilDiam = 4   'Default pupil diameter 1))8 A@,  
    Else gwMNYMI  
        pupilDiam = CDbl(dlg.TextBox2) P= NDS2  
    End If lL3U8}vn  
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    Print " " q0vQa  
    Print "Accommodation = " & A & " Diopters" V 5mTP'  
    Print "Pupil Diameter = " & pupilDiam & " mm" _Fl9>C"u  
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    ' Calculate new parameters with accommodation Y$_B1_  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness m-, x<bM?
 
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 8l`*]1.W<  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens :$c |  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens F]&*ow  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens } q8ASYNc  
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    tlens = 3.767 + 0.04*A                  'Lens thickness NBGH_6DROw  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction kxv1Hn"`{E  
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    'Adjust parameters to account for accommodation b\2 ds,  
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    '************************************************************************* a:w#s}bL  
    'Aqueous thickness (Position of Lens) @o`AmC. 8  
    '************************************************************************* =Xr.'(U  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) NgPk&niM  
    GetCustomElement eID, entity ?Ir:g=RP*  
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    parID = FindFullName( "Geometry.Arizona Eye" ) dy[X3jQB  
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    ' Delete any shift(s) in z 8":Q)9;%  
    count = 0 D0f]$  
    While GetOperationCount(eID)>count ;2QP7PrSY  
        GetOperation eID, count, op 3JR+O<3D  
        If op.Type="ShiftZ" Then +NUG  
            DeleteOperation eID,count @r1_U,0e  
            count=count-1 R:qW;n%AF  
        End If f!X[c?Xy"  
        count=count+1 Z%UP6%  
    Wend >A"(KSNL  
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    'Set new shift in ");a3hD  
    op.Type = "ShiftZ" Ny/MJ#Lq  
    op.val1 = taq Q7CsJzk~)  
    op.parent = parID ;O,jUiQ  
    AddOperation eID, op (TM,V!G+U~  
    Print "Set aqueous humor thickness = " & taq-0.55 @H8EWTZ  
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    '************************************************************************* ns4,@C$  
    'Radius and conic constant of anterior lens jPkn[W# 6  
    '************************************************************************* *oix6  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) E]r?{t`]  
    GetConic eID, entity, curv, conic 0"z9Q\{}  
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    SetConic eID, entity, 1/Rant, CCant |_U= z;Y  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant u*9V&>o  
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    '************************************************************************* .=; ;  
    'Radius and conic constant of posterior lens
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    '************************************************************************* N'=gep0
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) LDa1X2N  
    GetConic eID, entity, curv, conic >yDZ
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    SetConic eID, entity, 1/Rpost, CCpost X}0cCdW  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost q@2siI~W  
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    '************************************************************************* 8q7
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    'Lens thickness (Position of posterior lens surface)  !}$$:  
    '************************************************************************* sDV Q#}a  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) g9F?z2^  
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    ' Delete any z-shift(s) Z3!`J&  
    count = 0 "
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    While GetOperationCount(eID)>count P!k{u^$L  
        GetOperation eID, count, op TL#3
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        If op.Type="ShiftZ" Then }ad|g6i
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            DeleteOperation eID,count / XIhj  
            count=count-1 SgOheN-  
        End If <a+Z;>  
        count=count+1 Y<8vw d  
    Wend 3;Fhg!ZO  
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    'Set new z-shift {(}By/_  
    op.Type = "ShiftZ" 3R VR  
    op.val1 = tlens 3+bt~J0  
    op.parent = parID nQS|Lt_+  
    AddOperation eID, op [ikOb8 G#  
    Print "Set lens thickness = " & tlens +nGAz{&@r%  
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    '************************************************************************* gZ1?G-Q  
    'Lens index of refraction @=kSo -SX  
    '************************************************************************* )dSi/  
    eID = FindMaterial( "Lens" ) H>@+om  
    GetModelMaterial eID, mat |^H5^k "Bv  
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    mat.Nd = nlens ,7b[!#?8  
    SetModelMaterial eID, mat >F&47Yn  
    Print "Set lens index of refraction = " & nlens 7VI*N)OZ8  
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    '************************************************************************* X\F|Tk3_  
    'Pupil diameter *uvQ\.  
    '************************************************************************* !{41!O,K#  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) t&DEb_"De  
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    'Adjust pupil diameter (trimming volume inner hole) & ZB  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" sn>~O4"  
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    ' Adjust pupil location to just in front of the lens Y[S1$(K&*  
    parID = FindFullName( "Geometry.Arizona Eye" ) HUOj0T  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 7J&4akT{9  
    count = 0 u>/ TE  
    While GetOperationCount(eID)>count GvlS%  
        GetOperation eID, count, op GowH]MO  
        If op.Type="ShiftZ" Then 2)~>
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            DeleteOperation eID,count ei5~&  
            count=count-1 gltBC${7wZ  
        End If da~],MN  
        count=count+1 c6/=Gq
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    Wend W`*r>`krVJ  
    op.Type = "ShiftZ" s&J]zb`  
    op.val1 = taq-0.01 & "B=/-(  
    op.parent = parID >i-"<&#jG  
    AddOperation eID, op Vs{|xG7WD  
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    Print "Set pupil diameter = " & pupilDiam -s'-eQF J  
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    'Update AZ Eye subassembly Description pcI uN  
    eID = FindFullName( "Geometry.Arizona Eye" ) ji,kkipY?w  
    GetEntity eID, entity k.15CA`  
    entity.Description = "Accommodation = " & A & "D" cPc</[x[W  
    SetEntity eID, entity -1@<=jX3_  
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    Update _oDz-  
    Print "DONE!" ;P&OX5~V  
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End Sub *G9V'9  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： BJo*'US-Q  
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Accommodation = 4 Diopters ]:/Q]n^  
Pupil Diameter = 4 mm ib791  
Set aqueous humor thickness = 2.81 zs#@jv$  
Set anterior lens radius = 10.4 and conic constant = -2.375869 i
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Set posterior lens radius = -4.424557 and conic constant = -3.081019 `n?DU;,  
Set lens thickness = 3.927 >~+ELVB&  
Set lens index of refraction = 1.42672 % +\."eC  
Set pupil diameter = 4 YkQd  
DONE! -1ub^f
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