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    [转载]FRED运用: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: 2016-02-24
    简介 cgi:"y F  
    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。 E&N~ h|CL  
    :8`~dj.  
    模型 aJ QzM  
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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。 b Rc,Y<  
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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. M1icj~Jr  
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    光源 4T-"\tmg/  
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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。 DL<;qhte  
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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。 {- &`@V  
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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。 G c \^Kg^#  
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    图2. 字母F光源的设定方法光 F{4v[WP)  
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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 ('{aOiSH  
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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。  o*Xfgc  
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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。 ;: &|DN3;  
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    图5. 视网膜重点采样规格设定
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    脚本 rvlvk"  
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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: R+U$;r8l  
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    图6. 用户对话框的创建与编辑
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    图7. 用户对话框编辑器
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    如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 51`&%V{daL  
    余下的脚本计算与屈光度有关的所有参数。 r^a:s]  
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    分析 eXMIRus(  
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    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 7nPcm;Er  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 -pIz-*  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. y|)VNnWM  
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    Dim entity As T_ENTITY k qL.ZR  
    Dim op As T_OPERATION f@$W5*j  
    Dim mat As T_MODELMATERIAL BM/o7%]n  
    Dim A As Double - om9 Z0e  
    Dim pupilDiam As Double "a= Hr4C*r  
    Dim eID As Long e MHz/;I  
    Dim parID As Long /OWwC%tM/  
    Dim count As Integer Scx!h.\5  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double uDP:kM  
    Dim tlens As Double, nlens As Double OxYAM,F  
    Dim curv As Double, conic As Double DnFzCJ  
    Dim ok As Long /IG{j}  
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    Sub Main Ps>:|j+  
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        '用户输入对话框 _ ,s^  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 `!/[9Y#Hp  
            TextBox 220,21,40,21,.TextBox1 'default: 0 '9Z`y_~)G  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 `hZh}K^  
            OKButton 40,91,90,21  =aZ d>{Y  
            CancelButton 190,91,90,21 aZ4?! JW.  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ZX` \so,&,  
            TextBox 220,49,40,21,.TextBox2 'default: 4 KCW2 UyE]  
        End Dialog VaY#_80$s  
        Dim dlg As UserDialog )\#*~73  
    hAAh  
        ok = Dialog (dlg) mLqqo2u  
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        If ok=0 Then    'cancel button was pressed P,ueLG=  
            Print "Execution cancelled." N?ccG\t  
            End 3fhY+$tq  
        End If {KNaJ/:>W  
    J<;io!  
        'Assign accommodation and pupil diameter & use defaults if field left empty xy7A^7Li  
        If dlg.TextBox1 = "" Then I09 W=  
            A = 0           'Default accommodation Tj#S')s8  
        Else ~c35Y9-5  
            A = CDbl(dlg.TextBox1) ?!P0UTe~  
        End If J`U]Ux/L  
    xeSch?}  
        If dlg.TextBox2 = "" Then 'RV96lX<  
            pupilDiam = 4   'Default pupil diameter >) u;X  
        Else BV B2$&eJ  
            pupilDiam = CDbl(dlg.TextBox2) (|K+1R  
        End If PPB/-F]rr  
    .DhI3'Jrl  
        Print " " x.*^dM@V  
        Print "Accommodation = " & A & " Diopters" .oyAi||  
        Print "Pupil Diameter = " & pupilDiam & " mm" |${4sUR  
    ~^1y(-cw  
        ' Calculate new parameters with accommodation 1`K-f m)  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ZPmqoR[  
    Eo6N'h>h  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens VGc*aQYa  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens q*UHzE:LI  
    miaH,hm  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ] #@:VR  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens lH4Nbluc^  
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        tlens = 3.767 + 0.04*A                  'Lens thickness (p[#[CI9  
    %=UD~5!G0  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ik(Du/  
    ?>h ~"D#  
        'Adjust parameters to account for accommodation [t?tLUg|6  
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        '************************************************************************* .D 4G;=Q  
        'Aqueous thickness (Position of Lens) jg710.v:  
        '************************************************************************* 'Gn>~m  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ojy^ A  
        GetCustomElement eID, entity <R7{W"QTA)  
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        parID = FindFullName( "Geometry.Arizona Eye" ) lV$JCNe  
    -wXeue},>  
        ' Delete any shift(s) in z +>#SNZ[  
        count = 0 rkjnw@x\  
        While GetOperationCount(eID)>count A3a//e  
            GetOperation eID, count, op ~.W]x~X$  
            If op.Type="ShiftZ" Then UH!(`Z\C  
                DeleteOperation eID,count i<"lXu  
                count=count-1 +-j-)WU?,  
            End If G ?$ @6  
            count=count+1 .yj@hpJM  
        Wend |fgUW.  
    =x8[%+  
        'Set new shift in ]bY|>q  
        op.Type = "ShiftZ" L+8ar9es  
        op.val1 = taq ~bZ$ d{o^  
        op.parent = parID ]Lub.r  
        AddOperation eID, op dEJqgp}\p  
        Print "Set aqueous humor thickness = " & taq-0.55 <N vw*yA  
    E{orezP  
        '************************************************************************* msmW2Zc  
        'Radius and conic constant of anterior lens = wD#H@h  
        '************************************************************************* u"HGT=Nl  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 1,fR kQ  
        GetConic eID, entity, curv, conic hTtn /j  
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        SetConic eID, entity, 1/Rant, CCant zKd@Ab  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant f;{Q ~  
    axnlI*!  
        '************************************************************************* eN=jWUoCh  
        'Radius and conic constant of posterior lens v&d1ACctJ  
        '************************************************************************* '#+&?6p  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Z mJ<h&  
        GetConic eID, entity, curv, conic OXEEpoU?V  
    p3M!H2W  
        SetConic eID, entity, 1/Rpost, CCpost ;M3%t=KV  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost UGO#o`.G}  
    (.4lsKN<  
        '************************************************************************* (DiduSJ  
        'Lens thickness (Position of posterior lens surface) iww/s  
        '************************************************************************* aFTWzz  
    O52 /fGt  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) O&l4/RtQ\)  
    oai=1vt@  
        ' Delete any z-shift(s) dVbFMQ&  
        count = 0 ^ }7O|Y7  
        While GetOperationCount(eID)>count (uC8M,I\  
            GetOperation eID, count, op !eF(WbU0  
            If op.Type="ShiftZ" Then 4'O,xC  
                DeleteOperation eID,count b}K,wAx  
                count=count-1 *5feB#  
            End If HA,o2jZ?In  
            count=count+1 q}LDFsU  
        Wend .ck?JXg  
    aZmN(AJ8v  
        'Set new z-shift ? Lg(,-:  
        op.Type = "ShiftZ" *~^63Nx!  
        op.val1 = tlens c~ R'`Q  
        op.parent = parID [M\ an6h6O  
        AddOperation eID, op RIMSXue*Ha  
        Print "Set lens thickness = " & tlens al2lC#Sy  
    <X)\P}"L4  
        '************************************************************************* l)NkTZ<]  
        'Lens index of refraction w/6X9d  
        '************************************************************************* 2^o7 ^S  
        eID = FindMaterial( "Lens" ) =%W:N|k  
        GetModelMaterial eID, mat p{w-  
    flmQNrC.8  
        mat.Nd = nlens .!o]oM U/  
        SetModelMaterial eID, mat 8US#SI'x  
        Print "Set lens index of refraction = " & nlens nj s:  
    ray3gM%JLj  
        '************************************************************************* h.EI(Ev"GN  
        'Pupil diameter pAy4%|(  
        '************************************************************************* ^-"Iw y  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) AT&K>NG  
    \;&;K'   
        'Adjust pupil diameter (trimming volume inner hole) gzs \C{4D  
    "6jt$-?  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 3x;UAi+&  
    KfiSQ!{  
        ' Adjust pupil location to just in front of the lens &>\;4E.O5  
        parID = FindFullName( "Geometry.Arizona Eye" ) So 1TH%  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Q a (Sb  
        count = 0 Jpapl%7v  
        While GetOperationCount(eID)>count [.}qi[=n  
            GetOperation eID, count, op KqG b+N-@  
            If op.Type="ShiftZ" Then h*fN]k6  
                DeleteOperation eID,count T~E;@weR  
                count=count-1 t W UI?\  
            End If s;vt2>;q+e  
            count=count+1 NW[K/`-CTH  
        Wend NVMn7H}>  
        op.Type = "ShiftZ" Qf~>5(,h  
        op.val1 = taq-0.01 nqy*>X`  
        op.parent = parID Q4cCg7|0  
        AddOperation eID, op {xZY4b2  
    &Sd5]r@+  
        Print "Set pupil diameter = " & pupilDiam U6&`s%mIa  
    q=X<QhK  
        'Update AZ Eye subassembly Description "L~Oj&AN[  
        eID = FindFullName( "Geometry.Arizona Eye" ) uz!8=,DFw  
        GetEntity eID, entity lAN&d;NU6Z  
        entity.Description = "Accommodation = " & A & "D" @ [;'b$T$  
        SetEntity eID, entity )-4c@  
    6$b =Tr=0  
        Update 3;v)f":[  
        Print "DONE!" 1K9.3n   
         zQ=b|p]|W  
    End Sub oLoc jj~T  
    <MS>7Fd2  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: ?,$:~O* w  
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    Accommodation = 4 Diopters )Eozo4~  
    Pupil Diameter = 4 mm 4FaO+Eo,8  
    Set aqueous humor thickness = 2.81 -9dZT  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 $V87=_}  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 ]'pfw9"f~  
    Set lens thickness = 3.927 Zv %>m  
    Set lens index of refraction = 1.42672 wH|%3 @eJ  
    Set pupil diameter = 4 {"'M2w:|D1  
    DONE! @(#vg\UH  
    }uIQ@f`  
    (文章来源:讯技光电)
     
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