[技术]Arizona眼睛模型 [复制链接]

简介 GZ={G2@=I  
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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。 7Tbkti;  
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模型 9V&LJhDQ  
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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。 IFY!3^;zO  
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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. ^wlep1D  
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光源 v<wT`hiKW  
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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。 m+g>s&1H  
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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。 v4$,Vt:7  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 *C BCQp[$  
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视网膜的散射 5glGlD6R  
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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。 br
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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。 ]_?y[@ZP  
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脚本 0^[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： 1*h7L<#|mQ  
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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。 _=5ZB_I  
余下的脚本计算与屈光度有关的所有参数。 FS:WbFmc  
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分析 <.ky1aex7  
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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。 qgNK!(kWpr  
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脚本代码 0 ,-b %X  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. W<"\hQI  
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Dim entity As T_ENTITY e%6{P  
Dim op As T_OPERATION m1
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Dim mat As T_MODELMATERIAL Phu| hx<  
Dim A As Double -::%9D}P|  
Dim pupilDiam As Double "'Uk0>d=_I  
Dim eID As Long sdQv:nd'R  
Dim parID As Long (_ah~VnO  
Dim count As Integer h>0<@UP  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ,~(}lvqVH  
Dim tlens As Double, nlens As Double VsEAo  
Dim curv As Double, conic As Double Hw&M2a  
Dim ok As Long ^ {f^WL=  
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Sub Main Xf9%A2 iB  
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    '用户输入对话框 #Ca's'j&f  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ;NE/!!  
        TextBox 220,21,40,21,.TextBox1 'default: 0 om?CFl  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 _`>7 Q),7  
        OKButton 40,91,90,21 9'g{<(R]  
        CancelButton 190,91,90,21 7"ps#)O  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 <z2mNq  
        TextBox 220,49,40,21,.TextBox2 'default: 4 E2'e}RQ  
    End Dialog %+a@|Z  
    Dim dlg As UserDialog / LM  
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    ok = Dialog (dlg) 9X9zIh]JV  
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    If ok=0 Then    'cancel button was pressed 2-!Mao"^  
        Print "Execution cancelled." +|)1_NK  
        End } <4[(N  
    End If \N+Ta:U1P  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ?3,tG z)  
    If dlg.TextBox1 = "" Then lFGxW 5  
        A = 0           'Default accommodation UMQW#$~C{g  
    Else b.q"
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        A = CDbl(dlg.TextBox1) h\*rv5\M  
    End If ,9wenr  
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    If dlg.TextBox2 = "" Then <<5 :zlb  
        pupilDiam = 4   'Default pupil diameter ESjJHZoD(  
    Else =^y{@[p`(  
        pupilDiam = CDbl(dlg.TextBox2) (Zg'pSs)  
    End If xWz;5=7a]  
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    Print " " Kx185Q'W  
    Print "Accommodation = " & A & " Diopters" ^.kAZSgO  
    Print "Pupil Diameter = " & pupilDiam & " mm" \}QuNwc  
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    ' Calculate new parameters with accommodation 'oZn<c`  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness vLFaZ
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens pkfOM"5'  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens emY5xZ@N  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens #IhLpO  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens V/9"Xmv75  
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    tlens = 3.767 + 0.04*A                  'Lens thickness 6Y_O^f  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction `}8@[iB'  
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    'Adjust parameters to account for accommodation d3=6MX[c  
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    '************************************************************************* :Mu8W_  
    'Aqueous thickness (Position of Lens) 4B8Se  
    '************************************************************************* C:GHP$/}  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ?V)C9@bp  
    GetCustomElement eID, entity MRg\FR2>1  
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    parID = FindFullName( "Geometry.Arizona Eye" ) `TD%M`a  
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    ' Delete any shift(s) in z a3dzok  
    count = 0 7|M
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    While GetOperationCount(eID)>count .1}rzh}8  
        GetOperation eID, count, op R-A'v&=  
        If op.Type="ShiftZ" Then [zTYiNa  
            DeleteOperation eID,count DPS1GO*  
            count=count-1 RnA&-\|*  
        End If OT}Yr9h4  
        count=count+1 _{*$>1q  
    Wend K[LVT]3 n  
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    'Set new shift in ;;w6b:}-c  
    op.Type = "ShiftZ" WW[`E  
    op.val1 = taq N{V5 D  
    op.parent = parID jQxPOl$-  
    AddOperation eID, op T7lj39pJq  
    Print "Set aqueous humor thickness = " & taq-0.55 N?=qEX|R  
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    '************************************************************************* *pb:9JKi  
    'Radius and conic constant of anterior lens `b.o&t$L  
    '************************************************************************* 8>VI$   
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) SGBVR^  
    GetConic eID, entity, curv, conic }}``~  
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    SetConic eID, entity, 1/Rant, CCant pqH( Tbjq  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant wj#J>C2]  
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    '************************************************************************* qb-2QPEB  
    'Radius and conic constant of posterior lens iFnOl*TC  
    '************************************************************************* ~X~xE]1o|U  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Wd^lt7(j  
    GetConic eID, entity, curv, conic X"TUe>cM  
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    SetConic eID, entity, 1/Rpost, CCpost YHO;IQ5  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ovQS ET18b  
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    '************************************************************************* OAW=Pozr9  
    'Lens thickness (Position of posterior lens surface) |C$:]MZx  
    '************************************************************************* % U
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 9
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    ' Delete any z-shift(s) |{7e#ww]  
    count = 0 MK-a$~<  
    While GetOperationCount(eID)>count RRS~ xOg  
        GetOperation eID, count, op Dm|gSv8d,  
        If op.Type="ShiftZ" Then ^eaRgNz  
            DeleteOperation eID,count k1f3?l vlU  
            count=count-1 42Aje  
        End If 8S.')<-f  
        count=count+1 /FP~jV!z  
    Wend 9feD!0A  
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    'Set new z-shift 670J{b  
    op.Type = "ShiftZ" B@cJ
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    op.val1 = tlens IwTr'}XIw  
    op.parent = parID m\*&2Na  
    AddOperation eID, op 6P%<[Z  
    Print "Set lens thickness = " & tlens lFiq<3Nk  
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    '************************************************************************* -O~C m}e  
    'Lens index of refraction 3AdP^B<  
    '************************************************************************* '^Pq(b~  
    eID = FindMaterial( "Lens" ) wUru1_zjO  
    GetModelMaterial eID, mat  &7L~PZ  
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    mat.Nd = nlens ov\Ct%]  
    SetModelMaterial eID, mat jo,6Aog|u  
    Print "Set lens index of refraction = " & nlens 9nng}em>.  
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    '************************************************************************* WdTbt  
    'Pupil diameter $"Y3mD}?L  
    '************************************************************************* V.K70)]  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) n\Z^K  
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    'Adjust pupil diameter (trimming volume inner hole) =gW"#ZjL){  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 9M1a*f
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    ' Adjust pupil location to just in front of the lens ~8jThi U  
    parID = FindFullName( "Geometry.Arizona Eye" ) D-Bv(/Pz]$  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) -/M9 vS  
    count = 0 JZ %`%rA  
    While GetOperationCount(eID)>count PzIy">plm  
        GetOperation eID, count, op ijvNmn1k  
        If op.Type="ShiftZ" Then t*o7,  
            DeleteOperation eID,count \# 7@a74  
            count=count-1 -,R0IGS  
        End If Qe2m8  
        count=count+1
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    Wend IM[54_I  
    op.Type = "ShiftZ" &[NVP&9&U  
    op.val1 = taq-0.01 /t$rX3A  
    op.parent = parID P-[fHCg~  
    AddOperation eID, op a;56k  
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    Print "Set pupil diameter = " & pupilDiam &\&'L|0F  
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    'Update AZ Eye subassembly Description ?$<SCN=  
    eID = FindFullName( "Geometry.Arizona Eye" ) hbVE; 9  
    GetEntity eID, entity IKvd!,0xf  
    entity.Description = "Accommodation = " & A & "D" n)tU9@4Np  
    SetEntity eID, entity Xf6fH O  
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    Update 86
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    Print "DONE!" +*n]tlk  
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End Sub nARxn#<+  
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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： ~@xT]D!BQ  
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Accommodation = 4 Diopters l &}piC  
Pupil Diameter = 4 mm 0xN!DvCg>.  
Set aqueous humor thickness = 2.81 +z+F-  
Set anterior lens radius = 10.4 and conic constant = -2.375869 7Aqn[1{_O  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 XxhsPFv  
Set lens thickness = 3.927 =\M)6"}y}  
Set lens index of refraction = 1.42672 :b"=KQ  
Set pupil diameter = 4 I9;xzES  
DONE! "Lb fF