[技术]Arizona眼睛模型 [复制链接]

简介 -S,ir  
/%uZKGP  
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。 u1;e*t
y  
]~\SR0  
模型 2JA&{c
h  
fsrg2:kQ  
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。 s0)qlm*  
N8kb-2  
)7I.N]=  
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. TDl!qp @  
HTDyuqs  
光源 y'_V/w s  
Q.9Ph ~  
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。 kj{rk^x  
//X e*0  
of+phMev  
yZ;k@t_WRD  
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。 kJurUDo  
XWUvP  
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。 f/0v'
Jt  
+q #Xy0u  
hy$M
V3LP  
Et}C`vZ+Ve  
视网膜的散射 HzD>-f  
`R=a@DQ  
在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 23}BW_m  
28T\@zi  
b`h%W"|2L  
~T>jBYI0  
注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 nr<WO~Xw~  
RwAbIXG{0  
aCU7w5  
x{NNx:T1  
脚本 ><;l:RGK|  
L.09\1?.n  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： r@*=|0(OrK  
).0V%}>  
="3a%\  
WFU?o[k-O  
如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 l zfD)TWb  
余下的脚本计算与屈光度有关的所有参数。 _`bS[%CJ  
{BFT  
分析 JqI6k6~Q^  
v87$NQvwQ  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 M1AZ}bc0]  
@9Oe
C O  
=cf{f]N
 
脚本代码 )"
(V*Z  
*.kj]BoO  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. P$p@5hl  
sg3h i"Im  
Dim entity As T_ENTITY KI Ek/]<H  
Dim op As T_OPERATION -Wl)Lez@  
Dim mat As T_MODELMATERIAL PHQ{-b?4t  
Dim A As Double :D"@6PC]  
Dim pupilDiam As Double y
#b;uDY  
Dim eID As Long <A#5v\{.;~  
Dim parID As Long IXGW2z;  
Dim count As Integer LQh^; ]^(  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double  M*d-z  
Dim tlens As Double, nlens As Double 2Ryp@c&r^  
Dim curv As Double, conic As Double jg~_'4f#  
Dim ok As Long HA$Y1}  
q{a#HnZo"  
Sub Main >?S\~Y  
"#*
Nnt  
    '用户输入对话框 B }6Kd  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 NNwc!x)*  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ~k9O5S{  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 F|ETug n  
        OKButton 40,91,90,21 CfQf7-  
        CancelButton 190,91,90,21 }C=Quy%Z<  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 'eqiYY|  
        TextBox 220,49,40,21,.TextBox2 'default: 4 @q,)fBZq  
    End Dialog 'b8R#R\P  
    Dim dlg As UserDialog aQ&uC )w  
{J{1`@  
    ok = Dialog (dlg) jyNb(Z  
FI\IY R  
    If ok=0 Then    'cancel button was pressed fCLcU@3W?  
        Print "Execution cancelled." -r!42`S  
        End / >%L[RJ4  
    End If j2M4H@  
K6E}";;  
    'Assign accommodation and pupil diameter & use defaults if field left empty hQJo~'W=  
    If dlg.TextBox1 = "" Then >W'j9+Va  
        A = 0           'Default accommodation [1NaH  
    Else <lFdexH"T  
        A = CDbl(dlg.TextBox1) 8fnR1mWG  
    End If ]K7`-p~T  
(/'h4KS@  
    If dlg.TextBox2 = "" Then :JR<SFjm  
        pupilDiam = 4   'Default pupil diameter 
FS8S68  
    Else @\ }sb]  
        pupilDiam = CDbl(dlg.TextBox2) jM*AL X  
    End If 7k `_#  
3:UA<&=s  
    Print " " UIn^_}jF`  
    Print "Accommodation = " & A & " Diopters" d^tVD`Fm  
    Print "Pupil Diameter = " & pupilDiam & " mm" N3ZiGD  
t')h{2&&!2  
    ' Calculate new parameters with accommodation jA,|JgN|n  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness h77IWo6%  
Lj iI+NJ  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens )`<6taKx@n  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens lDC}HC  
|-n ('gQ[  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens )U'yUUi  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 85} ii{S  
pzg&/m&F`  
    tlens = 3.767 + 0.04*A                  'Lens thickness D{R/#vM jk  
<^Nk.E  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction dsK/6yu  
@LcT-3u  
    'Adjust parameters to account for accommodation SBX|Bcyk*  
u%xDsTDP  
    '************************************************************************* b"t")U==  
    'Aqueous thickness (Position of Lens) ~6kJ~R4  
    '************************************************************************* O] H=s  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) uWTN2jr
 
    GetCustomElement eID, entity kQ~ %=pn  
EMhr6</  
    parID = FindFullName( "Geometry.Arizona Eye" ) t=i/xG:5  
`dO}L  
    ' Delete any shift(s) in z YN^T$,*  
    count = 0 O^0"  
    While GetOperationCount(eID)>count ;b1wk^,Hw~  
        GetOperation eID, count, op /~*Cp9F"]  
        If op.Type="ShiftZ" Then S*g`d;8gV  
            DeleteOperation eID,count xZyeX34{M;  
            count=count-1 UW/N MjK  
        End If T/5"}P`  
        count=count+1 )tD6=Iz^5  
    Wend ~0ooRUWU7  
Mn@$;\:  
    'Set new shift in r4
?b0&Xq  
    op.Type = "ShiftZ" >t0%?wj)Y  
    op.val1 = taq +2Ql~w@$^l  
    op.parent = parID 61Bhm:O5W  
    AddOperation eID, op 69/?7r  
    Print "Set aqueous humor thickness = " & taq-0.55 88g47>{X  
s^cc@C  
    '************************************************************************* {i>Jfl]G}  
    'Radius and conic constant of anterior lens thptm  
    '************************************************************************* 5oJ Dux }  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) z,
x"a  
    GetConic eID, entity, curv, conic  ,1 P[  
~ezCu
_  
    SetConic eID, entity, 1/Rant, CCant /$:U$JVb?l  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant jTfi@5aPY  
SX+4HJB  
    '************************************************************************* vbp-`M
(  
    'Radius and conic constant of posterior lens %
`+'v_iu  
    '************************************************************************* x@m<Ym-  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) c#QFG1  
    GetConic eID, entity, curv, conic
Qn.[{rw  
QrC/ssf}  
    SetConic eID, entity, 1/Rpost, CCpost VNj@5s  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 8;#AO8+U7)  
-72j:nk  
    '************************************************************************* 9tk" :ld  
    'Lens thickness (Position of posterior lens surface) IqUp4}  
    '************************************************************************* J>%t<xYf4  
LeHiT>aX!  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) FVgMmYU  
V7C1FV2  
    ' Delete any z-shift(s) rl?7W];  
    count = 0 @o#+5P  
    While GetOperationCount(eID)>count Uo6(|mm  
        GetOperation eID, count, op w^{!U  
        If op.Type="ShiftZ" Then .GCR!V  
            DeleteOperation eID,count 2+'|kt2  
            count=count-1 &g0g]G21*I  
        End If yN\e{;z`  
        count=count+1 U-EhPAB@  
    Wend ?2ItB`<(  
#s2B%X  
    'Set new z-shift [AR>?6G-  
    op.Type = "ShiftZ" DZs^ 2Zc  
    op.val1 = tlens p<5!02yQ\  
    op.parent = parID B1$ikY  
    AddOperation eID, op >SDpuG&>  
    Print "Set lens thickness = " & tlens 0E6lmz`O  
jPk c3dG +  
    '*************************************************************************  KG8W8&q  
    'Lens index of refraction tZA:  
    '************************************************************************* )~ z Z'^  
    eID = FindMaterial( "Lens" ) |^GyH$.  
    GetModelMaterial eID, mat i:Y\`J  
zOGR+Gq_Z  
    mat.Nd = nlens U<Jt50O  
    SetModelMaterial eID, mat jGD%r~lN  
    Print "Set lens index of refraction = " & nlens ."mlSW"Wm  
v
PmnN^  
    '************************************************************************* |!LnAh  
    'Pupil diameter 2 9#]Vr  
    '************************************************************************* ?QpNjsF  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 3KcaT5(&  
3t(c_:[%  
    'Adjust pupil diameter (trimming volume inner hole) ^od<JD4  
HZZDv+  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 2o5;Uz1{  
`;F2n2@  
    ' Adjust pupil location to just in front of the lens 6RK\}@^=K  
    parID = FindFullName( "Geometry.Arizona Eye" ) k^An97J  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) p=gX!4,9<  
    count = 0 - k`.j  
    While GetOperationCount(eID)>count it1/3y =]  
        GetOperation eID, count, op `.^ |]|u  
        If op.Type="ShiftZ" Then z%:&#1)  
            DeleteOperation eID,count [uR/M
 
            count=count-1 ?CY1]d  
        End If 'fY9a(Xt.  
        count=count+1 8&E}n(XE  
    Wend CMl~=[foW  
    op.Type = "ShiftZ" -MfQ&U  
    op.val1 = taq-0.01 FtIa*j^G  
    op.parent = parID ;dQAV\  
    AddOperation eID, op 9DE)S)e8  
g`?:=G:a*  
    Print "Set pupil diameter = " & pupilDiam tu}>:mk  
U<bYFuS"  
    'Update AZ Eye subassembly Description l
[%lE  
    eID = FindFullName( "Geometry.Arizona Eye" ) /fwgqFVk  
    GetEntity eID, entity =+oZtP-+o  
    entity.Description = "Accommodation = " & A & "D" #Ufo)\x  
    SetEntity eID, entity tZho
)[1  
%Q4i%:Qi  
    Update {THqz$KN  
    Print "DONE!" &s VadOBQ  
     G]*|H0j  
End Sub bQQVj?8jp  
qO()w  
如果屈光度是4，光瞳直径是4，则会输出如下数据： J?Iq9f  
3QCVgo i\  
Accommodation = 4 Diopters $YM_G=k  
Pupil Diameter = 4 mm ^^}Hs-{T  
Set aqueous humor thickness = 2.81 EUcKN1  
Set anterior lens radius = 10.4 and conic constant = -2.375869 {9'M0=  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 EW(J5/mn  
Set lens thickness = 3.927 Yx%bn?%;&  
Set lens index of refraction = 1.42672 [m2+9MMl  
Set pupil diameter = 4 !O)qYmK]|  
DONE! fN[8N$1-