[技术]Arizona眼睛模型 [复制链接]

简介 _D,f4.R  
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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。 m&0BbyE.z  
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模型 Q1\k`J  
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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。 +xBK^5/x  
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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. BI.k On=  
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光源 OK
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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。 Y\Qxdq  
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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。 $< K)fbG  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 kbp( a+5  
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视网膜的散射 H(G^O&ppdB  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 +fP/|A8P  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 [X">vaa  
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脚本 f5yux}A{  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： }EedHS  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 XHZ: mLf  
余下的脚本计算与屈光度有关的所有参数。 a?,[w'7FU  
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分析 MB8SB   
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ~6-"i0k  
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脚本代码 x>^3]m  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. };"+ O  
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Dim entity As T_ENTITY 5qd_>UHp  
Dim op As T_OPERATION {7=WU4$  
Dim mat As T_MODELMATERIAL G !1~i*P$u  
Dim A As Double hEv=T'*,K)  
Dim pupilDiam As Double ~3'RW0  
Dim eID As Long 9QH
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Dim parID As Long gv#c~cX]  
Dim count As Integer pFsCd"zv  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 8Q^6ibE  
Dim tlens As Double, nlens As Double 5oU`[&=Ob  
Dim curv As Double, conic As Double bB:r]*_ s]  
Dim ok As Long -Wlp=#9  
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Sub Main #*Yi4Cn<  
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    '用户输入对话框 M[YTk=IM#  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 JO2ZS6k[  
        TextBox 220,21,40,21,.TextBox1 'default: 0 =f4[=C$&`  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ':4}O#  
        OKButton 40,91,90,21 r=~WMDCz@  
        CancelButton 190,91,90,21 ceFsGdS  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 [lNqT1%]  
        TextBox 220,49,40,21,.TextBox2 'default: 4 K\IYx|Hm a  
    End Dialog &Y54QE".  
    Dim dlg As UserDialog ]6t]m2~\  
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    ok = Dialog (dlg) %RQC9!  
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    If ok=0 Then    'cancel button was pressed \7Gg2;TA6o  
        Print "Execution cancelled." .M9d*qp`S  
        End bJQ5- *F  
    End If $J QWfGwR  
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    'Assign accommodation and pupil diameter & use defaults if field left empty 8K\'Z  
    If dlg.TextBox1 = "" Then r}/yi  
        A = 0           'Default accommodation f^W[;w  
    Else ,vPe}OKj  
        A = CDbl(dlg.TextBox1) [3O^0-:6E  
    End If @br@[RpB  
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    If dlg.TextBox2 = "" Then }>MP{67Dm  
        pupilDiam = 4   'Default pupil diameter hLb;5u&!kW  
    Else B{7Kzwh;  
        pupilDiam = CDbl(dlg.TextBox2) ]y3pE}R  
    End If p91`<>Iw  
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    Print " " 4. 1rJa  
    Print "Accommodation = " & A & " Diopters" $[Tt#CJw  
    Print "Pupil Diameter = " & pupilDiam & " mm" I jZ]_*^!  
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    ' Calculate new parameters with accommodation H>60D|v[  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness .6> hD1'  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens L|&'jH)  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens PX;Vo~6  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens SArfczoB  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens M]}l^m>L  
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    tlens = 3.767 + 0.04*A                  'Lens thickness >qR7'QwP  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction OnZF6yfN=3  
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    'Adjust parameters to account for accommodation a%Uw;6|{  
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    '************************************************************************* kmryu
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    'Aqueous thickness (Position of Lens) HbcOTd)=5  
    '*************************************************************************
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    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) !X^Hi=aV  
    GetCustomElement eID, entity {vs 4vS6  
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    parID = FindFullName( "Geometry.Arizona Eye" ) w{pUUo:<  
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    ' Delete any shift(s) in z )FRM_$t  
    count = 0 <"W?<VjO  
    While GetOperationCount(eID)>count l :/&E 6 9  
        GetOperation eID, count, op ~A6"sb=  
        If op.Type="ShiftZ" Then fX_#S|DlSG  
            DeleteOperation eID,count W+_RhJ  
            count=count-1 OFA{ KZga  
        End If VZ$=6CavH  
        count=count+1 7W"/N#G  
    Wend [r(Qs|  
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    'Set new shift in BT]ua]T+  
    op.Type = "ShiftZ" |'tW=  
    op.val1 = taq F!JJ6d53y  
    op.parent = parID rz6uDJ"  
    AddOperation eID, op ['z!{Ez  
    Print "Set aqueous humor thickness = " & taq-0.55 %%>_B2vc  
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    '************************************************************************* Wt^|BjbB4  
    'Radius and conic constant of anterior lens QdQd(4/1  
    '************************************************************************* 6SVqRD<`  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Ir5WN_EaS  
    GetConic eID, entity, curv, conic ~4\,&HH  
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    SetConic eID, entity, 1/Rant, CCant 9}5K6aQ  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 1~J5uB
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    '************************************************************************* )t:7_M3  
    'Radius and conic constant of posterior lens n 6{2]&sd  
    '************************************************************************* h>alGLN>  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) -?<4Og[^  
    GetConic eID, entity, curv, conic 9GgA6#  
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    SetConic eID, entity, 1/Rpost, CCpost \?DR s  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 9I`Y-D  
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    '************************************************************************* k;I &.H  
    'Lens thickness (Position of posterior lens surface) n-o3  
    '************************************************************************* eWvo,

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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) :~zv t  
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    ' Delete any z-shift(s) Q$ri=uB;+  
    count = 0 F2 ~%zNe  
    While GetOperationCount(eID)>count {fV}gR2  
        GetOperation eID, count, op O oSb>Y/4  
        If op.Type="ShiftZ" Then r[_4Lo@G  
            DeleteOperation eID,count e8}Ezy"^  
            count=count-1 ~9=aT1S|  
        End If N j4IQ<OV  
        count=count+1 0:&ZnE}##  
    Wend b.F^vv"]]  
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    'Set new z-shift v>A=2i*j  
    op.Type = "ShiftZ" &<5+!cV=  
    op.val1 = tlens >^$2f&z  
    op.parent = parID 8i}< k$S  
    AddOperation eID, op TZRcd~5$  
    Print "Set lens thickness = " & tlens iWLa>z|,  
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    '************************************************************************* }P9Ap3?  
    'Lens index of refraction `zpbnxOL$T  
    '************************************************************************* ]"~51HQZ  
    eID = FindMaterial( "Lens" ) 8FkFM^\1L  
    GetModelMaterial eID, mat (k`{*!:1a  
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    mat.Nd = nlens B*1W`f  
    SetModelMaterial eID, mat q o 1lj"P  
    Print "Set lens index of refraction = " & nlens _:`!DIz~9}  
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    '************************************************************************* 7=XL!:P  
    'Pupil diameter %XTcP2pRJ  
    '************************************************************************* E7zm{BX]  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) WO<
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    'Adjust pupil diameter (trimming volume inner hole) !yOeW0/2[  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" BxK^?b[E8  
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    ' Adjust pupil location to just in front of the lens " =] -%B  
    parID = FindFullName( "Geometry.Arizona Eye" ) up'  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) =PHIpFIuk  
    count = 0 o4b~4h{%  
    While GetOperationCount(eID)>count X"fh@.  
        GetOperation eID, count, op 6\jf|:h  
        If op.Type="ShiftZ" Then 8>WVodv  
            DeleteOperation eID,count -fI@])$9J  
            count=count-1 76cG90!Z  
        End If 4Kwh?8.  
        count=count+1 ^!8P<y  
    Wend 1xE]6he4{T  
    op.Type = "ShiftZ" 4*.K'(S5fx  
    op.val1 = taq-0.01 -62'}%?A<C  
    op.parent = parID JPn$FQD  
    AddOperation eID, op  Ez~'^s@  
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    Print "Set pupil diameter = " & pupilDiam 41a.#o  
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    'Update AZ Eye subassembly Description `(6r3f~XJ  
    eID = FindFullName( "Geometry.Arizona Eye" ) 6]
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    GetEntity eID, entity '})0!g<Y  
    entity.Description = "Accommodation = " & A & "D" NcPgq?3p  
    SetEntity eID, entity [+m?G4[  
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    Update l1U=f]  
    Print "DONE!" 5}$b0<em~  
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End Sub K_?W\Yg   
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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： ~9)"!  
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Accommodation = 4 Diopters ^.k |SK`U  
Pupil Diameter = 4 mm p!O(Y6QM  
Set aqueous humor thickness = 2.81 {j5e9pg1L|  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ~=<}\a~  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 l {jmlT  
Set lens thickness = 3.927 R" )bDy?  
Set lens index of refraction = 1.42672 7@lS.w\#-  
Set pupil diameter = 4 G0u LmW70  
DONE! $N:Vo(*