Arizona眼睛模型

3^su%z_%   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。 9 [I ro   Y*Q(v   模型 esu6iU@   ;LrKXp   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。 4 |5ekwk   Table 1. AZ眼睛模型的定义 S5Px9&N8(   ci^-0l_O   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. 329xo03-[   Mm[%v t40   光源 O:BP35z_F   mifYk>J^9   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。 wA~Nfn ^   7T2W%JT-,   图1. 光源和提示信息使用 #i]@"R   q3P3euK3   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。 7R2)Klt   Iw<c 9w8   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#<PFT4i   图2. 字母F光源的设定方法光 u('OHPqq   PvB?57wkF   图3. 字母F在视网膜上位置点列图 <NAR'{f   a"1$z`ln   视网膜的散射 1Ev+':%   0,A?*CO   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。 6aK--k   Cg|uHI*   图4. 视网膜朗伯散射设定 Q.] )yqX6   !S-hv1bE   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。 }mGD`5[`   &T|-K\*   图5. 视网膜重点采样规格设定 uHIWbF<0oo   D8#q.OR]   脚本 ]`kvq0Gyb   k2WO*xa*   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： AP7W)S   图6. 用户对话框的创建与编辑 c]n03o   图7. 用户对话框编辑器 ii2Z}qe   $P@cS1sB   如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 3"hR:'ts   余下的脚本计算与屈光度有关的所有参数。 :58'U|   e ^qnUjMy   分析 MGz> ,c^wW   Ww@;9US 3   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ^0 lPv!2   图7. 字母F在视网膜上颜色分析 |G@)B!>   !491 \W0ZH   脚本代码 / IS WC   Ny'v/+nQ   Option Explicit     'Remove this to enable non-dimensioned variables to be used. \|t0~sRwh   Pb;`'<*U   Dim entity As T_ENTITY M(E_5@?3   Dim op As T_OPERATION }"x*xN   Dim mat As T_MODELMATERIAL |*NrS<"   Dim A As Double 8'[wa   Dim pupilDiam As Double T6r~OV5   Dim eID As Long (R<4"QbE   Dim parID As Long ~ 7Nyi dV;   Dim count As Integer R"o,m   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double g DG m32   Dim tlens As Double, nlens As Double c):*R ]=   Dim curv As Double, conic As Double &s;^q   Dim ok As Long x=#5\t9   Kx+Bc&X   Sub Main z\Y^x9   P$ef,ZW"       '用户输入对话框 ]+dl=SmF       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 vUs7#*           TextBox 220,21,40,21,.TextBox1 'default: 0 yjR O9           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 vxT"BvN           OKButton 40,91,90,21 Lp) 8SmN           CancelButton 190,91,90,21 jGhg~-m           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 P$>kBW53           TextBox 220,49,40,21,.TextBox2 'default: 4 9prsL#Fn       End Dialog JwtI(>cI       Dim dlg As UserDialog _5w?v~65   `>EvT7u       ok = Dialog (dlg) UjOhaj "h   }n%Rl\p       If ok=0 Then    'cancel button was pressed Z;'.pU~           Print "Execution cancelled." }t3FAy(%           End G)B q?=P       End If VFSn!o:C   2\\3<       'Assign accommodation and pupil diameter & use defaults if field left empty e=UVsYNx       If dlg.TextBox1 = "" Then i!oj&&           A = 0           'Default accommodation ?mR[A`J58       Else TK/' =8           A = CDbl(dlg.TextBox1) vW-`=30       End If sg"D;b:X   s [F' h-y       If dlg.TextBox2 = "" Then \u-e\w           pupilDiam = 4   'Default pupil diameter X7d.Ie       Else }lTZq|;A           pupilDiam = CDbl(dlg.TextBox2) |kNGpwpI       End If &qP-x98E?   L(n/uQ :       Print " " eoe^t:5&       Print "Accommodation = " & A & " Diopters" u<shhb-       Print "Pupil Diameter = " & pupilDiam & " mm" &:I +]G/W   k)K-mD``U       ' Calculate new parameters with accommodation 6Hbf9,vI       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness )USC   Qb't*2c%       Rant = 12.0 - 0.4*A                     'Radius of anterior lens i;hc]fYb=K       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens IPR tm!    J1p75c%       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens jc. JX _/       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens rYFau1   .e2A*9,       tlens = 3.767 + 0.04*A                  'Lens thickness {I-a;XBX   zL} ,`:(.       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction /4 LR0`A'   RYZE*lWUh       'Adjust parameters to account for accommodation n?LIphc \   XCIa2 Syo       '************************************************************************* ki~y@@ 3I       'Aqueous thickness (Position of Lens) _7#tgZyv       '************************************************************************* IbJ[Og^Qyu       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 3[=`uO0\7       GetCustomElement eID, entity yLz,V}   2>}\XKF).       parID = FindFullName( "Geometry.Arizona Eye" ) h [IYA1/y   ?5yH'9zE       ' Delete any shift(s) in z <@e+ -$       count = 0 jfY{z=*]u       While GetOperationCount(eID)>count k<Tez{<           GetOperation eID, count, op >GznG[Ku           If op.Type="ShiftZ" Then *Cnq2=A]A               DeleteOperation eID,count E!I               count=count-1 ?YO=J           End If 8_IOJ]:w           count=count+1 a}Fkx       Wend U$A7EFK'   PNJe&q0*       'Set new shift in 0Ox|^V       op.Type = "ShiftZ" $,;S\JmWP       op.val1 = taq kWs+2j       op.parent = parID iTLW<wG       AddOperation eID, op 1O9p YW5J       Print "Set aqueous humor thickness = " & taq-0.55 r9] rN   #A3v]'7B       '************************************************************************* o'eI(@{F=       'Radius and conic constant of anterior lens 2>$F0 M       '************************************************************************* JEsLF{       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) F:;!)H*       GetConic eID, entity, curv, conic whY~= lizn   ;V~rWzKM(       SetConic eID, entity, 1/Rant, CCant CzSZ>E$%U       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant If-,c^i   om}/f`       '************************************************************************* 7?MB8tJ5r4       'Radius and conic constant of posterior lens m4"N+_j       '************************************************************************* feI./E       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) G'O/JM       GetConic eID, entity, curv, conic 5pM&h~M   JY2/YDJ       SetConic eID, entity, 1/Rpost, CCpost `S\zqF<       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ~! ZmF(:   q]eFd6       '************************************************************************* tyEPU^PM       'Lens thickness (Position of posterior lens surface) hj&fQ}X       '************************************************************************* N-2([ v   j0iAU1~_VX       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) /mn-+u`K   ;8ET!&k*>E       ' Delete any z-shift(s) X (k{-|9]       count = 0 &|.hkR2k       While GetOperationCount(eID)>count WR/o @$/           GetOperation eID, count, op 46bl>yk9<           If op.Type="ShiftZ" Then 7v_i>_m]               DeleteOperation eID,count D<U 9m3               count=count-1 bVoU|`c           End If >ZT& `E           count=count+1 H Dmx@E.@       Wend #bT8QbJ(   =&A!C"qK4[       'Set new z-shift bLgL0}=n       op.Type = "ShiftZ" ~:>AR` 9G       op.val1 = tlens 7tSJniB       op.parent = parID D|d4:;7       AddOperation eID, op 7]Al*)       Print "Set lens thickness = " & tlens i;o}o*=   E *F*nd]K       '************************************************************************* U4>O\sU       'Lens index of refraction LY]nl3{E       '************************************************************************* VF)uu[ f9       eID = FindMaterial( "Lens" ) TUh&d5a9H       GetModelMaterial eID, mat DY9fF4[9a   . yZm^&       mat.Nd = nlens [X,A'Q       SetModelMaterial eID, mat QyPg |#T2>       Print "Set lens index of refraction = " & nlens VeZey)Q   XZS5B~E '       '************************************************************************* XrF3kz!44       'Pupil diameter ^=EjadVQ       '************************************************************************* o=pt_!i/       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 5Go0}'*%   #HeM,;Xp       'Adjust pupil diameter (trimming volume inner hole) !;%y$$gxh   b~7Jh:%@;       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" )^4hQ3BS   4j>fI)FUW       ' Adjust pupil location to just in front of the lens )kYOHS       parID = FindFullName( "Geometry.Arizona Eye" ) 3{"byfO#%       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ! ja[4.       count = 0 _%Bz,C8       While GetOperationCount(eID)>count ?O??cjiA@           GetOperation eID, count, op N{8"s&           If op.Type="ShiftZ" Then 4qhWm"&CM               DeleteOperation eID,count ) Qq'Wp3i               count=count-1 y&"!m}           End If g\U/&.}DN           count=count+1 B2 c@kru       Wend Ln.9|9       op.Type = "ShiftZ" 845 W>B       op.val1 = taq-0.01 ~-TOsRvxR       op.parent = parID J$Fnm\       AddOperation eID, op 38~PWKt   n@!wp/J,       Print "Set pupil diameter = " & pupilDiam MIq"Wy|Zs   A\z`c e!       'Update AZ Eye subassembly Description Yi(1^'Bi       eID = FindFullName( "Geometry.Arizona Eye" ) G"T\=cQz       GetEntity eID, entity _%y4q%#       entity.Description = "Accommodation = " & A & "D" q$ [n`w-       SetEntity eID, entity ;+ azeW^   5 L/x-i       Update GIT#<+"       Print "DONE!" !Xj#@e        i|]7(z#OyI   End Sub 5t\HJ`C1Z   \M{[f=6llh   如果屈光度是4，光瞳直径是4，则会输出如下数据： 6<X%\[)n   ~i ,"87$[   Accommodation = 4 Diopters gAt~?HvW6   Pupil Diameter = 4 mm 03=5Nof1   Set aqueous humor thickness = 2.81 _X4!xbP   Set anterior lens radius = 10.4 and conic constant = -2.375869 yto[8;)_   Set posterior lens radius = -4.424557 and conic constant = -3.081019 K R,z^9   Set lens thickness = 3.927 48O~Jx,   Set lens index of refraction = 1.42672 ? }yfKU`   Set pupil diameter = 4 2N5`'   DONE!

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