[技术]Arizona眼睛模型 [复制链接]

简介 5N/%v&1  
?4q4J8j  
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。 Cjc6d4~  
+^=8ge}  
模型 l'/R&`-n  
kBD>-5Sn_T  
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。 {>DEsO  
0yuS3VY)  
A v2 08}Y  
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. +@p% p  
+ HK8jCa  
光源 ]G5w6&d  
}:us:%  
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。 n1ly y0%u  
7UVzp v  
OY;*zk  
Xq_5Qv  
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。 GP?M!C,/}k  
wr$M$i:  
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。 ST:A<Da"  
wt!nMQ  
zgNc4B  
ew#B[[  
视网膜的散射 ?[g=F <r  
Jk7|{W\OA  
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。 g;qx">xJ`o  
6p?,(  
:N4t49i  
pWK(z[D  
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。 &PYK8}pBk3  
W6?pswQ  

S?{#r  
* w?N{.  
脚本 FbS|~Rp~  
f&BY/ 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： x=b7':nQ  
/Z~<CbKKl  
'gC_)rK*  
W+UfGk}A  
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。 pGJ>O/%  
余下的脚本计算与屈光度有关的所有参数。 D8Ykg >B;&  
#gz M|  
分析 n>ULRgiT:o  
DI:]GED"=  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 $c0h.t  
l_o
@miG/  
v|uAzM{73  
脚本代码 a%kQl^I4  
Al}6q{E9+8  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. /|tJ6T1LrB  
JmxH"7hTE  
Dim entity As T_ENTITY }&cu/o4  
Dim op As T_OPERATION 41`n1:-]  
Dim mat As T_MODELMATERIAL c~z82iXNO  
Dim A As Double a1C{(f)  
Dim pupilDiam As Double X:HacYqtC  
Dim eID As Long ?[@J8  
Dim parID As Long /t+f{VX$  
Dim count As Integer B"h#C!E  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double NQBpX  
Dim tlens As Double, nlens As Double D{GfLib"U  
Dim curv As Double, conic As Double K2TcOFQ  
Dim ok As Long B2
>H_dmQ  
#|L8tuWW  
Sub Main z@!`:'ak  
U{2BVqM  
    '用户输入对话框 zk$FkbX  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 b$
N2z  
        TextBox 220,21,40,21,.TextBox1 'default: 0 X{5vXT\/y  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Bt@^+vH ~  
        OKButton 40,91,90,21 01wX`"I  
        CancelButton 190,91,90,21 cG[l!Z  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 Of*Pw[vD  
        TextBox 220,49,40,21,.TextBox2 'default: 4 .nrMfl_  
    End Dialog \UPjf]&  
    Dim dlg As UserDialog VCV"S>aVf  
6wBx;y |  
    ok = Dialog (dlg) ^uKwB;@  
$ `ov4W  
    If ok=0 Then    'cancel button was pressed C'9Cr}cZ.  
        Print "Execution cancelled." SheM|I~de  
        End Ka
PAa:Q  
    End If J%u=Ucdh  
o} J&E{Tk  
    'Assign accommodation and pupil diameter & use defaults if field left empty ,]bhyp  
    If dlg.TextBox1 = "" Then Sdp&jZY  
        A = 0           'Default accommodation )#?"Gjf~  
    Else `7c~mypx  
        A = CDbl(dlg.TextBox1) &v56#lG  
    End If '*K:  lx  
YmL06<Mh  
    If dlg.TextBox2 = "" Then s2h@~y  
        pupilDiam = 4   'Default pupil diameter ``,fodA8  
    Else }JF13beU  
        pupilDiam = CDbl(dlg.TextBox2) MLXNZd  
    End If 3x`|  
*:Y%HAy*  
    Print " " ,f~J`3(&  
    Print "Accommodation = " & A & " Diopters" ]] !VK  
    Print "Pupil Diameter = " & pupilDiam & " mm" ,|3MG",@@h  
F^WP<0C  
    ' Calculate new parameters with accommodation p2#)A"  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness PRx8I .  
+9M^7/}H  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens K*%9)hq  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens caIL&G,  
@@R7p  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Xnt~]k\"  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens +[M6X} TQ  
W<bGDh  
    tlens = 3.767 + 0.04*A                  'Lens thickness I4'5P}1yp  
DVG(Vw  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction #*D)Q/k  
MX$0Op  
    'Adjust parameters to account for accommodation ZT'`hK_up  
qU+t/C.  
    '************************************************************************* 1#C4;3i,  
    'Aqueous thickness (Position of Lens) (SWYOMo"  
    '************************************************************************* Iox
gjUa  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 5y
d MMb  
    GetCustomElement eID, entity Bn^0^J-  
! +a.Ei  
    parID = FindFullName( "Geometry.Arizona Eye" ) rNrxaRQ  
CnU*Jb  
    ' Delete any shift(s) in z Nkjza:f{  
    count = 0 #H)vK"hF  
    While GetOperationCount(eID)>count \9cbI3rGz  
        GetOperation eID, count, op :G [|CPm-  
        If op.Type="ShiftZ" Then /$ w%Q-p  
            DeleteOperation eID,count t#V!8EpBg  
            count=count-1 &:;:"{t}Do  
        End If hB"fhX  
        count=count+1 AS!?q  
    Wend &b.=M>\9Q  
{ME2ImD  
    'Set new shift in *M[?bk~~  
    op.Type = "ShiftZ" Cl5uS%g  
    op.val1 = taq 2L:_rR#w  
    op.parent = parID GOj-)i/_  
    AddOperation eID, op DH[p\Wy'  
    Print "Set aqueous humor thickness = " & taq-0.55 SbND Y{5RO  
?}Z1bH  
    '************************************************************************* ed]=\Key  
    'Radius and conic constant of anterior lens GD
&uQ`Y5  
    '************************************************************************* 6o!!=}'E[  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) }QN1|mP2  
    GetConic eID, entity, curv, conic %oF
}HF.  
@GPCwE1  
    SetConic eID, entity, 1/Rant, CCant spGb!Y`mR  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant }d[ kxo  
!Xh=k36  
    '************************************************************************* L(/e&J@><  
    'Radius and conic constant of posterior lens Y4OPEo5o  
    '************************************************************************* qt"G[9;  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) NiNM{[3oS  
    GetConic eID, entity, curv, conic =qoWCmg"&  
T%x}Y#U'`  
    SetConic eID, entity, 1/Rpost, CCpost zE336  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost :I"2V  
h(<,fg1  
    '************************************************************************* Um}  
    'Lens thickness (Position of posterior lens surface) ob+b<HFv  
    '************************************************************************* qPWP&k  
FGPB:  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ynmWW^dg  
6}Vf\j~  
    ' Delete any z-shift(s) kj|6iG  
    count = 0 rR$h*  
    While GetOperationCount(eID)>count \(J8#V  
        GetOperation eID, count, op $Ad{Z  
        If op.Type="ShiftZ" Then jG6]A"
pr  
            DeleteOperation eID,count Z_PNI#h*
 
            count=count-1 CHdX;'`*  
        End If 8&;UO{  
        count=count+1 Eou~P h*t  
    Wend gMv.V{vD  
efSM`!%j  
    'Set new z-shift ZWii)0'PV  
    op.Type = "ShiftZ" ~{*7"o/  
    op.val1 = tlens +ylTGSZS  
    op.parent = parID -B>++r2A^  
    AddOperation eID, op /Y*WBTV'  
    Print "Set lens thickness = " & tlens 1da@3xaF  
JBD7h5|Lc  
    '************************************************************************* ylUrLQ\  
    'Lens index of refraction <z+t,<3D  
    '************************************************************************* Okgv!Nt8)A  
    eID = FindMaterial( "Lens" ) cO-7ke  
    GetModelMaterial eID, mat R7]l{2V#^  
zqd@EF6/bz  
    mat.Nd = nlens :fKl]XO  
    SetModelMaterial eID, mat V @rI`~$  
    Print "Set lens index of refraction = " & nlens ,4hJT  
B*
qi_{Gp  
    '************************************************************************* pb^i^tA+A  
    'Pupil diameter 2^XGGB0  
    '************************************************************************* Z<U6<{b  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) OHv[#xGuV?  
9*$t!r{B@  
    'Adjust pupil diameter (trimming volume inner hole) 3NZK*!@'  
M])ZK  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 3sc+3-TF  
(w&F/ynO:  
    ' Adjust pupil location to just in front of the lens RFKtr  
    parID = FindFullName( "Geometry.Arizona Eye" ) k2E0/ @f{k  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) JgG$?n\  
    count = 0 $v,dz_O*\  
    While GetOperationCount(eID)>count &6DMk-  
        GetOperation eID, count, op hS_6  
        If op.Type="ShiftZ" Then QU#w%|
  
            DeleteOperation eID,count ;g8R4!J  
            count=count-1 dCb`xR}  
        End If TPVVck-T8  
        count=count+1 w'L\?pI  
    Wend R{RwTN<  
    op.Type = "ShiftZ" ;V@WtZv  
    op.val1 = taq-0.01 xrlmKSPa  
    op.parent = parID tM2)k+fg  
    AddOperation eID, op $J4 *U  
J5*tJoCYS  
    Print "Set pupil diameter = " & pupilDiam 8m5p_\&  
Q)"C&)`l  
    'Update AZ Eye subassembly Description aGK?x1_  
    eID = FindFullName( "Geometry.Arizona Eye" ) SH3|sXH<  
    GetEntity eID, entity n-5W*zk1  
    entity.Description = "Accommodation = " & A & "D" =b38(\  
    SetEntity eID, entity aHlcfh9|  
`/_o!(Z`  
    Update Gn&-X]Rrl  
    Print "DONE!" Z.d7U~_  
     )iq-yjO6  
End Sub pqUCqo!m\  
 R=.4  
如果屈光度是4，光瞳直径是4，则会输出如下数据： ?MXejE
C  
`L:CA5sBud  
Accommodation = 4 Diopters "mX\&%i6\p  
Pupil Diameter = 4 mm *Kyw^DI  
Set aqueous humor thickness = 2.81 .b\$MZ"(  
Set anterior lens radius = 10.4 and conic constant = -2.375869 vesJEaw7  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 & +4gSr  
Set lens thickness = 3.927 ^?$W
VB  
Set lens index of refraction = 1.42672 `IOs-%s  
Set pupil diameter = 4 lW<PoT  
DONE! m7&O9?X