[分享]Arizona眼睛模型 [复制链接]

简介 0^41dfdE  
3[g%T2&[  
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。 T[}A7a6g_  
[*<F   
模型 iNX%Zk[  
P8N`t&r"7  
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。 U{vt9t  
0j^QY6  
$^Is|]^  
在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. tiZ5 :^$b4  
}fps~R  
光源 nyyKA_#:5  
t6GL/
M4  
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。 ~s@PP'!  
^ lrq`1k  
/;7\HZ$@/  
mR
e BS  
除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 B{UL(6\B  
*=Ko"v }  
在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 v=kQ/h  
_g|zDi^  
!_Z\K$Ns  
:DI``]Si\  
视网膜的散射 _MF:?p,l  
,(H`E?m1w4  
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。 ;JM%O8  
W(h].'N  
UF3g]>*  
B$R"Ntp  
注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 fqoI(/RWP  
C
`
s  
L*a:j  
F*`*5:7  
脚本 P9Yee!*H  
)Gf"#TM[  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： h<)YZ
[;x  
bC_qoI<   
K`7
(*!HEb  
7jss3^.wA  
如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 dQX<X}  
余下的脚本计算与屈光度有关的所有参数。 z_Em%
X  
c1!0Z28  
分析 `w&Y[8+E  
v|IPus|>  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 =<,>dBs}\  
nitKX.t8  
|;~kHc$W  
脚本代码 v5 |XyN"  
tM&O<6Y  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. I4[sf  
 rG#o*oA  
Dim entity As T_ENTITY $1aJdZC7  
Dim op As T_OPERATION ]i$
<<u  
Dim mat As T_MODELMATERIAL 8>U{>]WG  
Dim A As Double s|p,UK  
Dim pupilDiam As Double ( (.b&  
Dim eID As Long >XTDN  
Dim parID As Long ]H ze  
Dim count As Integer D<V[:~-o  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double MR=dQc  
Dim tlens As Double, nlens As Double @1+gY4g  
Dim curv As Double, conic As Double ;iol 2  
Dim ok As Long .A(QqL>  
C)x>/Qr~  
Sub Main $&fP%p  
jXa;ovPK  
    '用户输入对话框 NOC8h\s}(  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 *d~).z)  
        TextBox 220,21,40,21,.TextBox1 'default: 0 C?xah?Sk  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 HPGIz!o  
        OKButton 40,91,90,21 kn$2_I9  
        CancelButton 190,91,90,21 l(irNKutgo  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 8iv0&91Z  
        TextBox 220,49,40,21,.TextBox2 'default: 4 eo#2n8I>=1  
    End Dialog XZh1/b^DMN  
    Dim dlg As UserDialog /Bt+Ov3k  
FfeX;pi  
    ok = Dialog (dlg) Ch] `@(l  
(]_smsok  
    If ok=0 Then    'cancel button was pressed %S`ygc}|  
        Print "Execution cancelled." xbVvK+  
        End 9Dat oi  
    End If EgE%NY~  
3^jkd)xw  
    'Assign accommodation and pupil diameter & use defaults if field left empty UFE# J  
    If dlg.TextBox1 = "" Then 5`_UIYcI  
        A = 0           'Default accommodation oouhP1py,  
    Else be<7Vy]j  
        A = CDbl(dlg.TextBox1)
g!QX#_~Il  
    End If [Re.sX}$Y  
f9%M:cl  
    If dlg.TextBox2 = "" Then pr=f6~Z-y  
        pupilDiam = 4   'Default pupil diameter buj*L&  
    Else zl]Ic' _i  
        pupilDiam = CDbl(dlg.TextBox2) c"wk_#  
    End If O:%,.??<%  
=<BPoGs5  
    Print " " E;o "^[we  
    Print "Accommodation = " & A & " Diopters" zfsGf'U  
    Print "Pupil Diameter = " & pupilDiam & " mm" e) \PW1b  
Ii.0Bul  
    ' Calculate new parameters with accommodation IPVD^a?  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ZwFVtR  
sahXPl%;U  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens lH%%iYBM  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens w/1Os!p  
6_=t~9sY  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 1B0+dxN`  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens M#u~]?hS  
t}Q PPp y  
    tlens = 3.767 + 0.04*A                  'Lens thickness m=4hi(g  
LykB2]T  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction TOH+JL8L  
t/vw%|AS  
    'Adjust parameters to account for accommodation 2ophh/]  
_xmS$z)TO  
    '************************************************************************* it.'.aK4  
    'Aqueous thickness (Position of Lens) .T\jEH8E  
    '************************************************************************* J$D/-*/@  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) Y& p ~8  
    GetCustomElement eID, entity U
hX)?'J  
W<c95Q
D.  
    parID = FindFullName( "Geometry.Arizona Eye" ) EyDH-}Y  
fG,)`[eD!_  
    ' Delete any shift(s) in z }2]m]D@%7  
    count = 0 FoW|BGA~  
    While GetOperationCount(eID)>count KsDovy<  
        GetOperation eID, count, op s?yl4\]Muf  
        If op.Type="ShiftZ" Then 7L4~yazmK  
            DeleteOperation eID,count /D>G4PP<  
            count=count-1 '89nyx&W  
        End If V|hr9  
        count=count+1 S\S31pYT  
    Wend =M."^X  
ra|Ku!  
    'Set new shift in BCI[jfd7  
    op.Type = "ShiftZ" 2EC<8}CG  
    op.val1 = taq Fzk%eHG=  
    op.parent = parID e6i m_ Tk  
    AddOperation eID, op
`L m9!?  
    Print "Set aqueous humor thickness = " & taq-0.55 DyC
nL@  
\"|7o8  
    '************************************************************************* 08qM?{zo^  
    'Radius and conic constant of anterior lens kKs}E| T  
    '************************************************************************* (&!x2M  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) <i ";5+  
    GetConic eID, entity, curv, conic #/ HQ?3h]  

RQ;}+S  
    SetConic eID, entity, 1/Rant, CCant Ca}V5O  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant S7h?tR*u  
E#VF7 9L  
    '************************************************************************* |0nt u+  
    'Radius and conic constant of posterior lens 2o<aEn&7|e  
    '************************************************************************* aflBDo1c  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) $2>"2*,04  
    GetConic eID, entity, curv, conic il[waUfmD  
^0g!,L  
    SetConic eID, entity, 1/Rpost, CCpost 2rWPqG4e  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost NI85|*h  
,DD}o  
    '************************************************************************* D}OhmOu3  
    'Lens thickness (Position of posterior lens surface) >9Z7l63+}  
    '************************************************************************* 2v`Q;%7O  
K)#6&\0tT  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) BV)) #D9  
!7n`-#)  
    ' Delete any z-shift(s) |lMc6C  
    count = 0 Hn}m}A  
    While GetOperationCount(eID)>count OV/ &'rC  
        GetOperation eID, count, op >)edha*W]  
        If op.Type="ShiftZ" Then gv7@4G  
            DeleteOperation eID,count dYZB> OS  
            count=count-1 v!j%<H`NI  
        End If Gg y7xb  
        count=count+1 B)BR y%  
    Wend =\IUBH+C  
}$` PZUw>  
    'Set new z-shift 8|~M!<  
    op.Type = "ShiftZ" U"535<mR  
    op.val1 = tlens 5Bp>*MR/".  
    op.parent = parID |&
_(I  
    AddOperation eID, op |w.h97fj  
    Print "Set lens thickness = " & tlens |4!G@-2V:I  
N6BEl55 &  
    '************************************************************************* c!a1@G  
    'Lens index of refraction >">grDX  
    '************************************************************************* e
QJyO9$G  
    eID = FindMaterial( "Lens" ) C1x(4&h  
    GetModelMaterial eID, mat ~_|CXPiQ8  
NEt_UcC  
    mat.Nd = nlens 5s:g(gy3BR  
    SetModelMaterial eID, mat &sooXKlv|  
    Print "Set lens index of refraction = " & nlens [sl"\3)  
=%d.wH?dZ/  
    '************************************************************************* &#;lmYyaui  
    'Pupil diameter ,VZ<r5NT  
    '************************************************************************* ]\F}-I[  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 0RHjA&r3v  
lz4M)pL^  
    'Adjust pupil diameter (trimming volume inner hole) 9P
*p{O{_  
 g^))  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" co*XW  
KeWIC,kq  
    ' Adjust pupil location to just in front of the lens f@ .s(i=z  
    parID = FindFullName( "Geometry.Arizona Eye" ) QPX3a8w*  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) =a6e*f  
    count = 0 &R3#? 1,  
    While GetOperationCount(eID)>count >NZJ-:t  
        GetOperation eID, count, op Mo]  
        If op.Type="ShiftZ" Then %UB+N8x`a  
            DeleteOperation eID,count yJ?=HH?  
            count=count-1 cHon' tS  
        End If <tv"I-2  
        count=count+1 6SEq 2  
    Wend wRJ`RKJ-T  
    op.Type = "ShiftZ" pE6r7  
    op.val1 = taq-0.01 -Xt0=3,  
    op.parent = parID 3aFD*S  
    AddOperation eID, op r[P+F  
ivvm.7{  
    Print "Set pupil diameter = " & pupilDiam _+d*ljP)l3  
[s F/sa3  
    'Update AZ Eye subassembly Description Z`>m  
    eID = FindFullName( "Geometry.Arizona Eye" ) aK--D2@}i  
    GetEntity eID, entity Is>~P*2Y=  
    entity.Description = "Accommodation = " & A & "D" ?pV!`vp^{  
    SetEntity eID, entity  uE'Kk8  
R T/)<RT9  
    Update lbC9^~T+  
    Print "DONE!" _*n 4W^8  
     J#?z/3v(  
End Sub vA*Q}]Ov  
8UXtIuQ  
如果屈光度是4，光瞳直径是4，则会输出如下数据： %(>,eee_  
v8>bR|n5  
Accommodation = 4 Diopters 2I{kLN1TY  
Pupil Diameter = 4 mm |D1TSv}rZD  
Set aqueous humor thickness = 2.81 Ly]J-BTe  
Set anterior lens radius = 10.4 and conic constant = -2.375869 u6i
X&%e  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 %jxeh.B3B  
Set lens thickness = 3.927 =$#=w?~%  
Set lens index of refraction = 1.42672 H4uHCkj  
Set pupil diameter = 4 #O!gjZ,  
DONE! !_
>o2  
 e,T^
8_>  
y':65N
Mda  
QQ：2987619807 mj&$+zM>