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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 I0=_=aZO(  
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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。 OI R5QH  
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    模型 ijI/z5  
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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。 bP,<^zA|X  
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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. `h}eP[jA  
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    光源 e_BG%+;G,  
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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。 ^}3^|jF  
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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。 HN47/]"*  
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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。 4.6$m  
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    图2. 字母F光源的设定方法光 St=nf\P&F  
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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 T.q2tC[bR  
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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。 KaIKb=4L|  
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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。 &K[*vyD  
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    图5. 视网膜重点采样规格设定
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    脚本 |9@,ri\'Rg  
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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#Cb  
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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。  %zavSm"  
    余下的脚本计算与屈光度有关的所有参数。 $+gQnI3w  
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    分析 `At.$3B  
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    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 x"r0<RK  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 <y 4(!z"  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. u09Tlqh0 3  
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    Dim entity As T_ENTITY zcpL[@B  
    Dim op As T_OPERATION , 3R=8  
    Dim mat As T_MODELMATERIAL ; :e7Z^\/k  
    Dim A As Double wG3L+[,  
    Dim pupilDiam As Double E4#{&sRT  
    Dim eID As Long aRd~T6I  
    Dim parID As Long = XZU9df  
    Dim count As Integer glAS$<  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double [i.@q}c~E  
    Dim tlens As Double, nlens As Double #%,X),%-  
    Dim curv As Double, conic As Double 1N5 E  
    Dim ok As Long gt4GN`-k  
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    Sub Main O[X*F2LC4  
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        '用户输入对话框 Z bRRDXk!  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Za.}bR6?Y  
            TextBox 220,21,40,21,.TextBox1 'default: 0 cIug~ x>  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 5- dt0I@<  
            OKButton 40,91,90,21 =dm9+ff  
            CancelButton 190,91,90,21 WC_.j^sW  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 pj'gTQ),0  
            TextBox 220,49,40,21,.TextBox2 'default: 4 ]#~J[uk  
        End Dialog /Qgb t  
        Dim dlg As UserDialog 8 Ku9;VEk  
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        ok = Dialog (dlg) cGot0' mB  
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        If ok=0 Then    'cancel button was pressed +U fw  
            Print "Execution cancelled." >=k7#av  
            End Q`CuZkP(  
        End If Vjs2Yenx  
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        'Assign accommodation and pupil diameter & use defaults if field left empty u5CSx'h]  
        If dlg.TextBox1 = "" Then F6{g{ B  
            A = 0           'Default accommodation ;NP-tA)  
        Else <I,4Kc!  
            A = CDbl(dlg.TextBox1) f,YORJ  
        End If LP3#f{U  
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        If dlg.TextBox2 = "" Then 288mP]a(v_  
            pupilDiam = 4   'Default pupil diameter &Vj @){  
        Else CKw-HgXG  
            pupilDiam = CDbl(dlg.TextBox2) 97c0bgI!+  
        End If qw+ 7.h#V  
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        Print " " W83d$4\d  
        Print "Accommodation = " & A & " Diopters" DLwlA !z  
        Print "Pupil Diameter = " & pupilDiam & " mm" t!D'ZLw  
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        ' Calculate new parameters with accommodation tbQY&TO1  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness GEPWb[Oa  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens F'~r?D  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens kn#?+Q  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens d /jx8(0  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ?M90K)&g{  
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        tlens = 3.767 + 0.04*A                  'Lens thickness >A )Sl'  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction zkt~[-jm}  
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        'Adjust parameters to account for accommodation 51:5rN(_  
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        '************************************************************************* $#^3>u  
        'Aqueous thickness (Position of Lens) G-CL \G\n  
        '************************************************************************* .J.}}"+U  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) gd[muR ~  
        GetCustomElement eID, entity >$kFYb>~q  
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        parID = FindFullName( "Geometry.Arizona Eye" ) ->#wDL!6  
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        ' Delete any shift(s) in z 'q}Ud10c  
        count = 0 yCz"~c  
        While GetOperationCount(eID)>count mI2Gs) SO  
            GetOperation eID, count, op ZW M:Wj192  
            If op.Type="ShiftZ" Then h5{//0 y  
                DeleteOperation eID,count P]"@3Z&w  
                count=count-1 D[W ` q#W  
            End If *b;)7lj0h  
            count=count+1 *Y1s4FXu2  
        Wend 2k!uk6  
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        'Set new shift in C,;?`3bH@  
        op.Type = "ShiftZ" D~inR3(}  
        op.val1 = taq Gb2|e.z  
        op.parent = parID aT/2rMKPF  
        AddOperation eID, op zt2#K  
        Print "Set aqueous humor thickness = " & taq-0.55 DN9x<%/-  
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        '************************************************************************* @3eMvbI  
        'Radius and conic constant of anterior lens W}F~vx.  
        '*************************************************************************  [6@bsXiw  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) eDo4>k"5  
        GetConic eID, entity, curv, conic *K>2B99TXu  
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        SetConic eID, entity, 1/Rant, CCant bSM|"  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant W)`>'X`  
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        '************************************************************************* ;8VZsh  
        'Radius and conic constant of posterior lens 7<kr|-  
        '************************************************************************* !}A`6z  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) gy1kb,MO  
        GetConic eID, entity, curv, conic 0"-H34M <D  
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        SetConic eID, entity, 1/Rpost, CCpost y;0Zk~R$  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 'bv(T2d~~  
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        '************************************************************************* 'Q'-7z-6  
        'Lens thickness (Position of posterior lens surface) W9Us I  
        '************************************************************************* vU/sQt8  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 2AqcabI9  
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        ' Delete any z-shift(s) mGz'%?zj  
        count = 0 WbFCj0  
        While GetOperationCount(eID)>count v&sp;%I6=  
            GetOperation eID, count, op 4&]NC2I  
            If op.Type="ShiftZ" Then YC{7;=P f  
                DeleteOperation eID,count C _W]3  
                count=count-1 j%vxCs>  
            End If 48gpXcc@|  
            count=count+1 U ;4;>  
        Wend "{{@N4^  
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        'Set new z-shift _#<l -R`  
        op.Type = "ShiftZ" p<VW;1bt5  
        op.val1 = tlens <!u(_Bxw/  
        op.parent = parID B^1jd!m  
        AddOperation eID, op 8Z@O%\1x6  
        Print "Set lens thickness = " & tlens Rlr[uU_  
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        '************************************************************************* +SRM?av  
        'Lens index of refraction 4[0.M  
        '************************************************************************* sx9[#6~{Y  
        eID = FindMaterial( "Lens" ) j{5oXW  
        GetModelMaterial eID, mat jaTCRn3|<  
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        mat.Nd = nlens OUHd@up@n  
        SetModelMaterial eID, mat  GwD"j]  
        Print "Set lens index of refraction = " & nlens ^w RD|  
    _i"[m(ABj1  
        '************************************************************************* {.,y v>%  
        'Pupil diameter =66,$~g{  
        '************************************************************************* )o_$AbPt  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) piUfvw  
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        'Adjust pupil diameter (trimming volume inner hole) "%t !+E>nr  
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        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Lj3q?>D*^6  
    3TD!3p8  
        ' Adjust pupil location to just in front of the lens :n?}G0y  
        parID = FindFullName( "Geometry.Arizona Eye" ) '$OLU[(Y  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Y0OVzp9 b  
        count = 0 )ULxB'Dm  
        While GetOperationCount(eID)>count PDh1*bf{u  
            GetOperation eID, count, op PJcz] <  
            If op.Type="ShiftZ" Then rNHV  
                DeleteOperation eID,count 20uR?/|@  
                count=count-1 =>h~<88#5  
            End If @l2AL9z$m>  
            count=count+1 jr5x!@rb  
        Wend =HvLuVc  
        op.Type = "ShiftZ" _bq2h%G=8  
        op.val1 = taq-0.01 @*LESN>T@t  
        op.parent = parID xZ"kJ'C4}  
        AddOperation eID, op Q ?W6  
    }oTac  
        Print "Set pupil diameter = " & pupilDiam ">RDa<H]  
    'uOp?g'7  
        'Update AZ Eye subassembly Description D#9W [6  
        eID = FindFullName( "Geometry.Arizona Eye" ) 0g(hY:  
        GetEntity eID, entity 4a~9?}V:  
        entity.Description = "Accommodation = " & A & "D" QPa&kl  
        SetEntity eID, entity 7" cgj#  
    <<![3&p#  
        Update <tTn$<b  
        Print "DONE!" mE]W#?   
         =M9Od7\J  
    End Sub :U;ZBs3  
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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: WaWx5Fx+  
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    Accommodation = 4 Diopters !$5U\"M  
    Pupil Diameter = 4 mm #/1,Cv yj  
    Set aqueous humor thickness = 2.81 hpym!G  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 SIRZ_lt$r  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 CLD*\)QD\  
    Set lens thickness = 3.927 C31SXQ  
    Set lens index of refraction = 1.42672 A]vQ1*pnk  
    Set pupil diameter = 4 oZ~M`yOz.  
    DONE! jKu"Vi|j>  
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