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    [分享]Arizona眼睛模型 [复制链接]

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    只看楼主 倒序阅读 楼主  发表于: 2020-12-09
    简介 cI'n[G  
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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`h  
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    模型 V~[b`&F  
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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。 #55:qc>m  
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    Table 1. AZ眼睛模型的定义
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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.  Q&xH  
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    光源 I51]+gEN  
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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。 sWte&  
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    图1. 光源和提示信息使用
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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。 tngB;9c+w  
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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。 QR#>Ws  
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    图2. 字母F光源的设定方法光 x C&IR*  
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    图3. 字母F在视网膜上位置点列图
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    视网膜的散射 TPJF?.le '  
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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。 a%B&F|u  
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    图4. 视网膜朗伯散射设定
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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。 7Dbm s(:(  
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    图5. 视网膜重点采样规格设定
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    脚本 bpwA|H%{M  
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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: / S]RP>cQ  
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    图6. 用户对话框的创建与编辑
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    图7. 用户对话框编辑器
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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。 ?I6rW JcQ6  
    余下的脚本计算与屈光度有关的所有参数。 BA: x*(%~  
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    分析 s6 g"uF>k  
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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。 sh_;98^  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 s) ]j X  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. _M`ZF*o=c  
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    Dim entity As T_ENTITY z9ADF(J?0'  
    Dim op As T_OPERATION ?Tc#[B  
    Dim mat As T_MODELMATERIAL (0NffM1  
    Dim A As Double Q 84t=  
    Dim pupilDiam As Double I@KM2 KMN  
    Dim eID As Long 6/8K2_UeoW  
    Dim parID As Long xc#t8`  
    Dim count As Integer x8rg/y  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 5U~KYy^v  
    Dim tlens As Double, nlens As Double %42a>piev  
    Dim curv As Double, conic As Double r&E gP  
    Dim ok As Long |&=-Nm  
    [j0[c9.p [  
    Sub Main [Jt}^  
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        '用户输入对话框 8D )nM|  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 *,$5EN  
            TextBox 220,21,40,21,.TextBox1 'default: 0 bXnUz?1!d  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 \s*M5oN]]  
            OKButton 40,91,90,21 /9R0}4i7  
            CancelButton 190,91,90,21 fIoc)T  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 :0l+x 0l}  
            TextBox 220,49,40,21,.TextBox2 'default: 4 7{F\b  
        End Dialog M_ukG~/  
        Dim dlg As UserDialog wN!\$i@E:  
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        ok = Dialog (dlg) [LnPV2@e  
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        If ok=0 Then    'cancel button was pressed !l $d^y345  
            Print "Execution cancelled." :'DyZy2Fd  
            End Qfn:5B]tI  
        End If _Z0 .c@0  
    %b^4XTz  
        'Assign accommodation and pupil diameter & use defaults if field left empty t<Acq07  
        If dlg.TextBox1 = "" Then g{]6*`/Z  
            A = 0           'Default accommodation Z`tmuu  
        Else oPmz$]_Z  
            A = CDbl(dlg.TextBox1) YcobK#c  
        End If 0DicrnH8  
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        If dlg.TextBox2 = "" Then ))=6g@(  
            pupilDiam = 4   'Default pupil diameter 0V~zZ/e  
        Else nEsD+ }E?  
            pupilDiam = CDbl(dlg.TextBox2) i&:SWH=  
        End If NuQ!huh  
    7 XxZF43  
        Print " " k77IXT_7u  
        Print "Accommodation = " & A & " Diopters" U*C^g}iA  
        Print "Pupil Diameter = " & pupilDiam & " mm" MR1I"gqE}I  
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        ' Calculate new parameters with accommodation %P0  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 0 %~~IT}U  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens *K|~]r(F?  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 3*h"B$g!  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens qk<jvha  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens K KB+o)*W  
    [q?RJmB]  
        tlens = 3.767 + 0.04*A                  'Lens thickness 9w=7A>.U  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ?9\D(V  
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        'Adjust parameters to account for accommodation N\PdX$  
    r'*$'QY-N  
        '************************************************************************* N#ggT9>X  
        'Aqueous thickness (Position of Lens) qLCNANWnd  
        '************************************************************************* F{ %*(U  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) <<0sv9qw1  
        GetCustomElement eID, entity "TA0--6  
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        parID = FindFullName( "Geometry.Arizona Eye" ) @}4aF|  
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        ' Delete any shift(s) in z A08kwYxiW  
        count = 0 wtYgHC}X  
        While GetOperationCount(eID)>count 2=_$&oT**  
            GetOperation eID, count, op }b\hRy~=r  
            If op.Type="ShiftZ" Then |SOLC  
                DeleteOperation eID,count #yH+ENp0   
                count=count-1 T [SK>z  
            End If a$=~1@  
            count=count+1 76tn`4NIP  
        Wend OIPY,cj~  
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        'Set new shift in ,-Hj  
        op.Type = "ShiftZ" mXz*Gi  
        op.val1 = taq EX8+3>)  
        op.parent = parID !h.hJt  
        AddOperation eID, op U823q-x  
        Print "Set aqueous humor thickness = " & taq-0.55 w-n}&f  
    [#Qf#T%5h  
        '************************************************************************* 3&y-xZu]  
        'Radius and conic constant of anterior lens BEOPZ[Q|c  
        '************************************************************************* Wq4<9D  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) :IZAdlz[@  
        GetConic eID, entity, curv, conic ; dzL9P9IU  
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        SetConic eID, entity, 1/Rant, CCant #Nh'1@@  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant (F&LN!Hn>p  
    bA)nWWSg=  
        '************************************************************************* m#'eDO:  
        'Radius and conic constant of posterior lens Y!L-5|G  
        '************************************************************************* osXEzr(  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) pT|s#-}  
        GetConic eID, entity, curv, conic D|ceZ <9x  
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        SetConic eID, entity, 1/Rpost, CCpost t$$YiO  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost T_D3WHp  
    r]!#v{#.  
        '************************************************************************* *:n7B\.  
        'Lens thickness (Position of posterior lens surface) Lng. X8D  
        '************************************************************************* 94w)Yln  
    ^.6yzlY  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) M G$+Blw>  
    [h'u@%N|/  
        ' Delete any z-shift(s) ?>B?*IK!  
        count = 0 q@wD@_  
        While GetOperationCount(eID)>count c]u ieig0~  
            GetOperation eID, count, op ZPH_s^  
            If op.Type="ShiftZ" Then ;O}%SCF7  
                DeleteOperation eID,count gO8d2?Oh  
                count=count-1 Fl_}Auj{&(  
            End If ':(AiD-}  
            count=count+1 23tX"e  
        Wend a<&K^M&  
    {d.z/Buu  
        'Set new z-shift N~,Ipf  
        op.Type = "ShiftZ" _3aE]\O[  
        op.val1 = tlens 9K@ I  
        op.parent = parID 3Z" ;a  
        AddOperation eID, op SZW_V6\t>  
        Print "Set lens thickness = " & tlens HS <Jp44  
    )J[m>tyY5  
        '************************************************************************* j1;[6XG  
        'Lens index of refraction _|u}^MLO  
        '************************************************************************* ~s+vJvWz  
        eID = FindMaterial( "Lens" ) bh@CtnO  
        GetModelMaterial eID, mat Yk|6?e{+)  
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        mat.Nd = nlens =_`q;Tu=  
        SetModelMaterial eID, mat jQ V[zcM  
        Print "Set lens index of refraction = " & nlens n}UJ - \$  
    , Wd=!if  
        '************************************************************************* *F1TZ_GS  
        'Pupil diameter e8<}{N0,n  
        '************************************************************************* Z4i))%or  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) >pp/4Ia!  
    sMMOZ'bT  
        'Adjust pupil diameter (trimming volume inner hole) kf'(u..G  
    *>a=ku:?  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" "<=4]Z  
    Ef`'r))  
        ' Adjust pupil location to just in front of the lens W^8  
        parID = FindFullName( "Geometry.Arizona Eye" ) Da 7(jA+  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) TnN yth wZ  
        count = 0 KdkL_GSLT  
        While GetOperationCount(eID)>count UDI\o1Rbp  
            GetOperation eID, count, op a(vt"MQ_  
            If op.Type="ShiftZ" Then >1`4]%  
                DeleteOperation eID,count F\r"Y)|b=  
                count=count-1 1Rd|P<y  
            End If { YQS fk  
            count=count+1 , @jtD*c)  
        Wend NWn*_@7;  
        op.Type = "ShiftZ" :2KHiT5  
        op.val1 = taq-0.01 `/[5/%  
        op.parent = parID dE"_gwtX  
        AddOperation eID, op O5r8Ghf )  
    '! ^7 *@z  
        Print "Set pupil diameter = " & pupilDiam =Q<VU/  
    x\Q}fk?{t  
        'Update AZ Eye subassembly Description d3q%[[@  
        eID = FindFullName( "Geometry.Arizona Eye" ) ]B )nN':  
        GetEntity eID, entity ~Y`ys[Z m  
        entity.Description = "Accommodation = " & A & "D" *1EmK.-'u  
        SetEntity eID, entity 8vuTF*{yZ  
    N~flao^  
        Update ?7NSp2aq2A  
        Print "DONE!" u~OlJ1V  
         t[TM\j0jW  
    End Sub 9;LjM ~Ct  
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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: ]6M<c[H>  
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    Accommodation = 4 Diopters e$s&B!qJ  
    Pupil Diameter = 4 mm !!Ww#x~k$[  
    Set aqueous humor thickness = 2.81 >s5}pkAv|e  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 Az@@+?,%Y  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 W7n^]~V  
    Set lens thickness = 3.927 BX$<5S@  
    Set lens index of refraction = 1.42672 ^>E>\uz0v  
    Set pupil diameter = 4 v'?Smd1v /  
    DONE! 8?82 p  
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    QQ:2987619807 %j^QK>%  
     
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