Arizona眼睛模型

=~LJ3sIX   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。 N?`' /e   !^G\9"4A   模型 l,aay-E   .O<obq~;C   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。 AbW6x   Table 1. AZ眼睛模型的定义 C\hM =%   JC}D`h   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. }"%N4(Kd   _Y m2/3!   光源 {Qj~M<@3   (S Yln>o   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。 Bk{]g=DO   H3oFORh   图1. 光源和提示信息使用 % |L=l{g   =($xG#g`   除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 0JujesUw(   buHJB*?9   在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 86a\+Kz%%L   图2. 字母F光源的设定方法光 ba9?(+i$h   es0hm2HT3   图3. 字母F在视网膜上位置点列图 Ab;.5O$y   eS){1   视网膜的散射 ]T) 'Hb   @IZnFHN   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 bpa?C   [mueZQyI?0   图4. 视网膜朗伯散射设定 F,CTZ~   ;q>ah!"k   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 -$Ih@2"6   i,VMd   图5. 视网膜重点采样规格设定 {id4:^u&;   @>7%qS   脚本 Y}KNKO;   MiX43Pk]   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： iH'p>s5L   图6. 用户对话框的创建与编辑 G^@5H/)   图7. 用户对话框编辑器 RPbZ(.   h;'~,xA   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。 + >!;i6|   余下的脚本计算与屈光度有关的所有参数。 Vi|#@tC'   3PF_H$`oJ   分析 qmP].sA   b7ZSPXV   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ?gXp*>Kg[   图7. 字母F在视网膜上颜色分析 b#o|6HkW   gnHbb-<i,   脚本代码 ksm~<;td   iU:cW=W|M\   Option Explicit     'Remove this to enable non-dimensioned variables to be used. aDN`6[   TkF[x%o   Dim entity As T_ENTITY Pc]HP   Dim op As T_OPERATION 7-V/RChBm   Dim mat As T_MODELMATERIAL W}ofAkF   Dim A As Double u$`a7Lp,n   Dim pupilDiam As Double Ew$C ;&9   Dim eID As Long !ubD/KE   Dim parID As Long wdoR %b{M   Dim count As Integer f?)-}\[IR{   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double .A|@?p[   Dim tlens As Double, nlens As Double *=xr-!MEk   Dim curv As Double, conic As Double $Ygue5{c   Dim ok As Long Qv ?"b   FC4wwzb   Sub Main H6gSO(U   Kf -JcBsrT       '用户输入对话框 $Z>'Jp       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 K|s,ru           TextBox 220,21,40,21,.TextBox1 'default: 0 H0cA6I           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 [.}oyz;}N           OKButton 40,91,90,21 VG~Vs@c(           CancelButton 190,91,90,21 oD@7 SF           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 P+HXn8@           TextBox 220,49,40,21,.TextBox2 'default: 4 EBmt9S       End Dialog d0 /#nz       Dim dlg As UserDialog Ht&YC<X   y ~HP>~Oh       ok = Dialog (dlg) xd0 L{ue.   &Hnz8Or!       If ok=0 Then    'cancel button was pressed cl/_JQ&           Print "Execution cancelled." 8a"%0d#           End S`]k>' l       End If '4<1 1(U   N4HqLh23H       'Assign accommodation and pupil diameter & use defaults if field left empty ijU*|8n{>       If dlg.TextBox1 = "" Then K~EmD9           A = 0           'Default accommodation 2b8L\$1q       Else SZCze"`[           A = CDbl(dlg.TextBox1) rQ snhv       End If j _7mNIr   j*m%*_kO       If dlg.TextBox2 = "" Then ;xn0;V'=           pupilDiam = 4   'Default pupil diameter p{dj~ &v       Else GsM<2@?           pupilDiam = CDbl(dlg.TextBox2) caX< n>       End If 1yY0dOoLG)   @9|hMo       Print " " T&7qC=E#5       Print "Accommodation = " & A & " Diopters" 8Xs8A.       Print "Pupil Diameter = " & pupilDiam & " mm" | VDV<g5h   oe~b}:       ' Calculate new parameters with accommodation #A8sLkY       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness (&x['IR   sW8dPw O       Rant = 12.0 - 0.4*A                     'Radius of anterior lens r9G>jiw8       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens P{^6v=8)   Z;)%%V%o       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ]')RMg zM*       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ~4cC/"q$X   R0-j5&^jju       tlens = 3.767 + 0.04*A                  'Lens thickness y1L,0 ]   ENY+^7       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction |]*/R^1>2   l%i+cOD       'Adjust parameters to account for accommodation  %D "I   ^5 Tqy(M       '************************************************************************* e\75:oQ       'Aqueous thickness (Position of Lens) <1M-Ro?5k       '************************************************************************* , ++ `=o       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) Kx JqbLUC       GetCustomElement eID, entity h@@=M   SByW[JE       parID = FindFullName( "Geometry.Arizona Eye" ) y"wShAR   S>1Iky|       ' Delete any shift(s) in z jWfa;&Ra       count = 0 S|+o-[e8O       While GetOperationCount(eID)>count jEJT-*I1+           GetOperation eID, count, op xKp4*[}m           If op.Type="ShiftZ" Then UW EV^ &"x               DeleteOperation eID,count $* Kvc$D               count=count-1 N ZSSg2TX#           End If du^J2m{f           count=count+1 uu687|P m       Wend 3? +H d   !%0 *z       'Set new shift in L*JjG sTH       op.Type = "ShiftZ" lHX72s|V       op.val1 = taq kMd.h[X~       op.parent = parID H7:] ]j1       AddOperation eID, op N87B8rDl       Print "Set aqueous humor thickness = " & taq-0.55 B^9j@3Ux   ?6Y?a2 |       '************************************************************************* 3m)y|$R       'Radius and conic constant of anterior lens -3Vx76Y       '************************************************************************* M=r)I~       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) s->^=dy       GetConic eID, entity, curv, conic V "h +L7T   J/*`7Pd       SetConic eID, entity, 1/Rant, CCant sLQ^F       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ~/P[J   | %Vh`HT       '************************************************************************* ea')$gR       'Radius and conic constant of posterior lens d/DB nZN       '************************************************************************* [q #\D       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ixD)VcD-f       GetConic eID, entity, curv, conic 'Qe;vZ31K   04=c-~&q       SetConic eID, entity, 1/Rpost, CCpost E~oOKQ5W       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ]?[fsdAQW   BF{Y"8u$       '************************************************************************* d-dEQKI?;       'Lens thickness (Position of posterior lens surface) 0:Ol7       '************************************************************************* )hfpwdQ   >\3V a       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) "a U aotx   `+Q%oj#FF       ' Delete any z-shift(s) N//KPh       count = 0 t{vJM!kdlQ       While GetOperationCount(eID)>count a!AA]           GetOperation eID, count, op B_m8{44zM           If op.Type="ShiftZ" Then OpYY{f               DeleteOperation eID,count s,&Z=zt0R               count=count-1 pcWPH.           End If `RL"AH:+           count=count+1 WEi2=3dV       Wend z~/` 1   03#lX(MB       'Set new z-shift G*P#]eO       op.Type = "ShiftZ" 81 sG       op.val1 = tlens YteO6A;       op.parent = parID IB]l1<       AddOperation eID, op DN57p!z       Print "Set lens thickness = " & tlens wcY?rE9   }?Ai87-{       '************************************************************************* L0WN\|D       'Lens index of refraction 'AS|ZRr/       '************************************************************************* <B6H. P =       eID = FindMaterial( "Lens" ) Qjv}$`M       GetModelMaterial eID, mat ZX./P0   338k?nHxv       mat.Nd = nlens 7\Y0z       SetModelMaterial eID, mat zue~ce73J       Print "Set lens index of refraction = " & nlens %aVq+kC h   i6Emhji       '************************************************************************* ) ahA[       'Pupil diameter PBTnIU       '************************************************************************* cB}D^O        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) fHd#u%63K   [j/9neaye       'Adjust pupil diameter (trimming volume inner hole) Q:d]imw!O   Od,qbU4O       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" @O^6&\s>   57       ' Adjust pupil location to just in front of the lens ,S]7 'UP       parID = FindFullName( "Geometry.Arizona Eye" ) =R$u[~Xl2X       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) )W _v:?A9       count = 0 Tq n@P       While GetOperationCount(eID)>count CU2*z(]&           GetOperation eID, count, op w-L=LWL\           If op.Type="ShiftZ" Then EaY?aAuS:               DeleteOperation eID,count <FkFs{(t               count=count-1 XrGglBIV           End If 8\A#CQ5b           count=count+1 HJ[cM6$2       Wend @>2i+)=E5       op.Type = "ShiftZ" "CQa.%       op.val1 = taq-0.01 L2i_X@/       op.parent = parID 4*cEag        AddOperation eID, op a![{M<Y~   B7E:{9l~s{       Print "Set pupil diameter = " & pupilDiam tpQ(g%   r1{@Ucw2       'Update AZ Eye subassembly Description u.m[u)HQ       eID = FindFullName( "Geometry.Arizona Eye" )  ^7WN{0       GetEntity eID, entity " 9wvPC ^       entity.Description = "Accommodation = " & A & "D" 1FL~ndJs       SetEntity eID, entity 2E)-M9ds   x,pjpx       Update Q1I6$8:7       Print "DONE!" :vQrOn18p        nRZ]z( b   End Sub sfugY(m   `*N[jm"   如果屈光度是4，光瞳直径是4，则会输出如下数据： SBk4_J/_   ?(F6#" /E   Accommodation = 4 Diopters j[G   Pupil Diameter = 4 mm 17"uf.G   Set aqueous humor thickness = 2.81 VSI9U3t3w   Set anterior lens radius = 10.4 and conic constant = -2.375869 Zbt.t]N   Set posterior lens radius = -4.424557 and conic constant = -3.081019 S3*`jF>q   Set lens thickness = 3.927 XZ]uUP   Set lens index of refraction = 1.42672 bP$dU,@p~   Set pupil diameter = 4 lc1(t:"[   DONE!

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