[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 Vi'zSR28Z  
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。 nUf0TkA  
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模型 A#8J6xcSrL  
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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。 NY"+Qw@$  
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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. rBZ0Fx$/[  
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光源 e>g>)!F  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 PpezWo)9  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 =hi{J M  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 ;.Y-e Q,  
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视网膜的散射 ([dJ'OPx$  
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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。 =d#(n M*  
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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。 A$70!5*  
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脚本 3L:SJskYR  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： [xo-ZDIoG  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 Og7^7))  
余下的脚本计算与屈光度有关的所有参数。 _6-N+FI  
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分析 kK=f@
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ?-JW2 E"uT  
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脚本代码 XbIxGL  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. z}F^HQ1  
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Dim entity As T_ENTITY 5E^P2Mlc  
Dim op As T_OPERATION O Ke 9/._  
Dim mat As T_MODELMATERIAL X@za4d  
Dim A As Double \%_sL#?  
Dim pupilDiam As Double (t5vBUj  
Dim eID As Long }Z)YK}_1  
Dim parID As Long e[6Me[b  
Dim count As Integer 
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Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double d2fiPI7lg  
Dim tlens As Double, nlens As Double .|0$?w  
Dim curv As Double, conic As Double duc\/S'  
Dim ok As Long T?CQgVR  
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Sub Main `+i/rc1.  
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    '用户输入对话框 g){gF(  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 #'. '|z  
        TextBox 220,21,40,21,.TextBox1 'default: 0 2 SU  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 [8>#b_
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        OKButton 40,91,90,21 :XOjS[wBm  
        CancelButton 190,91,90,21 J^!wk
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        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 vAjog])9s  
        TextBox 220,49,40,21,.TextBox2 'default: 4
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    End Dialog 2 ,krVb?<  
    Dim dlg As UserDialog >sQf{uL  
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    ok = Dialog (dlg) N'0nt]&a  
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    If ok=0 Then    'cancel button was pressed $."Fz x  
        Print "Execution cancelled." E
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        End AoY!f'Z  
    End If }!"Cvu  
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    'Assign accommodation and pupil diameter & use defaults if field left empty (:R5"|]@<x  
    If dlg.TextBox1 = "" Then 8! /ue.T  
        A = 0           'Default accommodation #mD_<@@  
    Else l
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        A = CDbl(dlg.TextBox1) ng9_c  
    End If _-2;!L#/  
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    If dlg.TextBox2 = "" Then Mm!;+bM%  
        pupilDiam = 4   'Default pupil diameter h@J3+u<  
    Else n8JM 0 U-  
        pupilDiam = CDbl(dlg.TextBox2) 9*XT|B  
    End If C3~O6<,Jh  
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    Print " " {REGoe=W%  
    Print "Accommodation = " & A & " Diopters" _|{Z850AS  
    Print "Pupil Diameter = " & pupilDiam & " mm" [fY7|  
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    ' Calculate new parameters with accommodation 3GrIHiCr  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness At!@Rc  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens (M{>9rk8  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens &Lbwx&!0b  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens _C19eW'  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens a'd=szt  
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    tlens = 3.767 + 0.04*A                  'Lens thickness nWhf  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction "p+JME(  
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    'Adjust parameters to account for accommodation dp4vybJ  
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    '************************************************************************* riRG9c |  
    'Aqueous thickness (Position of Lens) TX7dwmt)N  
    '************************************************************************* "<f?.l\+  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 0g; o6Fg  
    GetCustomElement eID, entity 5Zmc3&vRl  
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    parID = FindFullName( "Geometry.Arizona Eye" ) h"'}Z^  
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    ' Delete any shift(s) in z 8k+k\V{  
    count = 0 L\!Oj5  
    While GetOperationCount(eID)>count 4,?beA  
        GetOperation eID, count, op lkC|g
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        If op.Type="ShiftZ" Then f1?%p)C  
            DeleteOperation eID,count Ocn@JOg  
            count=count-1 P+C5 
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        End If EQX<<x
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        count=count+1 [;o>q;75Jz  
    Wend BuUM~k&SY  
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    'Set new shift in CrG!8}  
    op.Type = "ShiftZ" &}K%F)S  
    op.val1 = taq P>$+XrTE  
    op.parent = parID InRcIQT  
    AddOperation eID, op u9u'5xAO  
    Print "Set aqueous humor thickness = " & taq-0.55 [nlq(DGJhp  
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    '*************************************************************************  kKY,&Fn-  
    'Radius and conic constant of anterior lens xMa9o  
    '************************************************************************* .F[5{XV  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) qT&zg@m  
    GetConic eID, entity, curv, conic `tcX[(`  
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    SetConic eID, entity, 1/Rant, CCant d`%7Pk  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ;%cW[*Dw  
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    '************************************************************************* T)Q_dF.N  
    'Radius and conic constant of posterior lens !89hO4 0r  
    '************************************************************************* 51*[Ibx  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) N P5K1:  
    GetConic eID, entity, curv, conic JXR]G  
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    SetConic eID, entity, 1/Rpost, CCpost /b/  6*&  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost NRspi_&4J  
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    '************************************************************************* 2 zG;91^  
    'Lens thickness (Position of posterior lens surface) _c-(T&u<  
    '************************************************************************* ps:E(\  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) I :b
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    ' Delete any z-shift(s) =Lnip<t>ja  
    count = 0 "v0SvV<7  
    While GetOperationCount(eID)>count KP$AT}D  
        GetOperation eID, count, op U!E}(9 tb
 
        If op.Type="ShiftZ" Then _::ssnG3jT  
            DeleteOperation eID,count {M=*>P]E  
            count=count-1 ic l]H  
        End If a=vH:D  
        count=count+1 i CB:p  
    Wend vj]h[=:  
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    'Set new z-shift &5[+p{2  
    op.Type = "ShiftZ"
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    op.val1 = tlens s?4nR:ZC}  
    op.parent = parID 73SH[
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    AddOperation eID, op @xBO[v  
    Print "Set lens thickness = " & tlens :h!'\9  
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    '************************************************************************* 2]FRIy d  
    'Lens index of refraction z\?<j%e!t  
    '************************************************************************* #B#xSmak  
    eID = FindMaterial( "Lens" ) sD&V_ &i  
    GetModelMaterial eID, mat LB9W.cA   
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    mat.Nd = nlens xr7M#n  
    SetModelMaterial eID, mat zJ:%iL@  
    Print "Set lens index of refraction = " & nlens z2!4w +2  
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    '************************************************************************* wM3m'# xJ  
    'Pupil diameter 5g$>J)Ry  
    '************************************************************************* IS;[oJef  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Z%=A[`5]  
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    'Adjust pupil diameter (trimming volume inner hole) 8U4In[4  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder"  Vo%Z|  
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    ' Adjust pupil location to just in front of the lens )r)ZmS5O  
    parID = FindFullName( "Geometry.Arizona Eye" ) !,]c}Y{i  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) [,MK)7DU  
    count = 0 `U>2H4P  
    While GetOperationCount(eID)>count BQ70<m2D$  
        GetOperation eID, count, op ELG9ts+5Uj  
        If op.Type="ShiftZ" Then y0/FyQs  
            DeleteOperation eID,count H0.A;`  
            count=count-1 /NobS'd  
        End If #EB Rc4>,  
        count=count+1 iun_z$I<+Z  
    Wend BNFYUcVP  
    op.Type = "ShiftZ" `R-?+76?  
    op.val1 = taq-0.01 .~q>e*8AH  
    op.parent = parID ZvO1=* J,  
    AddOperation eID, op WN#2<XjG  
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    Print "Set pupil diameter = " & pupilDiam In+2~Jw/2!  
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    'Update AZ Eye subassembly Description  acQHqR  
    eID = FindFullName( "Geometry.Arizona Eye" ) 2~B5?(g  
    GetEntity eID, entity QXl~a%lB  
    entity.Description = "Accommodation = " & A & "D" EQ|Wke  
    SetEntity eID, entity ?1] \3nj  
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    Update BglbQ'6p  
    Print "DONE!" 82?LZ?!PD  
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End Sub |L:X$oM  
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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： !C^>
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Accommodation = 4 Diopters }m7$,'C%P  
Pupil Diameter = 4 mm B7.&yXWgn  
Set aqueous humor thickness = 2.81 <E^;RG  
Set anterior lens radius = 10.4 and conic constant = -2.375869 _9Rj,  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 #uICHt3  
Set lens thickness = 3.927 LX=v _}l J  
Set lens index of refraction = 1.42672 d3#e7rQ8  
Set pupil diameter = 4 a$bE2'cb  
DONE! ziM@@$.F  
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