Arizona眼睛模型

CxDcY   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。 AbfZ++aJ   =K(JqSw+M   模型 8sg|MWSU   xS8,W   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。 3v1 7"   Table 1. AZ眼睛模型的定义 ar$*a>'?   RlRs}yF   在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. ,mKObMu   B!;+_%P76   光源 =6\LIbO   eT[&L @l]b   多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 F*` t"7Lm   W5SNI>|E   图1. 光源和提示信息使用 SK R1E];4   LZ<[ll#C   除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 {@.Vh ]   "0Q1qZ   在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 x2W#ROfg   图2. 字母F光源的设定方法光 66\jV6eH7L   +,5-qm)Gh>   图3. 字母F在视网膜上位置点列图 H}ZQ?uK;   |PP.<ce\-   视网膜的散射 0.Vi97`   5iM[sg[y9   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 V.=lGhi   #;Tz[0   图4. 视网膜朗伯散射设定 6F|j(LB   tFM$#JN   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。 h<x4YB5Mj   ~h)&&'a   图5. 视网膜重点采样规格设定 vH[Pb#f-   4kl Ao$   脚本 8P2 J2IU   [6tSYUZs   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： +L%IG   图6. 用户对话框的创建与编辑 X2yTlLdY   图7. 用户对话框编辑器 lAi2,bz"   %d;ezY'2   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。 <1"+,}'x   余下的脚本计算与屈光度有关的所有参数。 2+Rv{%   {whvTN1#dh   分析 Or0O/\D)   '@=PGpRF   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。  P_Hv%g   图7. 字母F在视网膜上颜色分析 6b=q-0yj   /+|#^:@   脚本代码 szmmu*F,U:   5@!st   Option Explicit     'Remove this to enable non-dimensioned variables to be used. =#xK=pRy;   S\#17.=   Dim entity As T_ENTITY D(]E/k@;~   Dim op As T_OPERATION ,"2TArC'z   Dim mat As T_MODELMATERIAL J'T=q/   Dim A As Double DAO]uh{6   Dim pupilDiam As Double 'T8 W!&$   Dim eID As Long s:>\/[*>0c   Dim parID As Long v]VWDT `   Dim count As Integer +-$Ko fnM   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double "Cz<d w]D   Dim tlens As Double, nlens As Double ~O6\6$3b5E   Dim curv As Double, conic As Double 1;F`c`0 <   Dim ok As Long gm)@c2?.   Zjh2{ :   Sub Main v|';!p|    jN*:QI       '用户输入对话框 PBjmGwg7       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 v6=-g$FG           TextBox 220,21,40,21,.TextBox1 'default: 0 [g|Y7.j8           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 MXtkP1A`           OKButton 40,91,90,21 `'S0*kMT           CancelButton 190,91,90,21 !wz/cM;           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 K`-!uZW:B7           TextBox 220,49,40,21,.TextBox2 'default: 4 /~p+j{0L3W       End Dialog Wr?'$:       Dim dlg As UserDialog c3TKl/   !ZXUPH       ok = Dialog (dlg) u9qMqeF   eD?3"!c!       If ok=0 Then    'cancel button was pressed 9ooY?J           Print "Execution cancelled." iEyeX0nm           End R:aa+MX(1       End If muON>^MbC   D<$Xy P       'Assign accommodation and pupil diameter & use defaults if field left empty WYcA8X/       If dlg.TextBox1 = "" Then 5VW|fI           A = 0           'Default accommodation #U mF-c       Else #KlCZ~s           A = CDbl(dlg.TextBox1) ;]2s,za)qs       End If ,M5}4E7L%s   `{v?6:G:Q       If dlg.TextBox2 = "" Then sBX-X$*N           pupilDiam = 4   'Default pupil diameter $FTO        Else (5L-G{4           pupilDiam = CDbl(dlg.TextBox2) )FN;+"IJ       End If Q,T"ZdQ   ~Ou1WnmO       Print " " W!Gdf^Yy<       Print "Accommodation = " & A & " Diopters" w*9br SK       Print "Pupil Diameter = " & pupilDiam & " mm" 1 T<+d5[C   K>:]Bx#F7       ' Calculate new parameters with accommodation 5K%SL1N       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 6?tlU>A2s   d~J-|yyT       Rant = 12.0 - 0.4*A                     'Radius of anterior lens bBcp9C)iY       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens t&q N: J   {V19Zv"j       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens SymwA S+       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens :nN1e   `O?T.p)       tlens = 3.767 + 0.04*A                  'Lens thickness B;6]NCxD   $lA V6I.       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction p/Sbt/R   Cs3^9m6;d       'Adjust parameters to account for accommodation ]va>ex$d   e>rRTN       '************************************************************************* EI~"L$?       'Aqueous thickness (Position of Lens) `$LWmm#       '************************************************************************* Rgy-OA       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) BAj-akc f       GetCustomElement eID, entity T VmH   INs!Ame2       parID = FindFullName( "Geometry.Arizona Eye" ) %q;jVj[   h5_G4J{1       ' Delete any shift(s) in z @Hb'8F       count = 0 1F8 W9b^D       While GetOperationCount(eID)>count u6V/JI}g           GetOperation eID, count, op `?g`bN`Vn           If op.Type="ShiftZ" Then }TQ{`a@               DeleteOperation eID,count Y}*\[}l:&x               count=count-1 U6Z R->:           End If lASL8O&\           count=count+1 N]EcEM#       Wend [S]S^ej*8   BcjP+$k4_       'Set new shift in ?^mi3VM       op.Type = "ShiftZ" x&Vm!,%:1       op.val1 = taq kqYa*| l       op.parent = parID V3;.{0k       AddOperation eID, op []R? ViG       Print "Set aqueous humor thickness = " & taq-0.55 /M~!sPW&?   9Y a<My       '************************************************************************* X=JmF97       'Radius and conic constant of anterior lens XIo55*       '************************************************************************* z{"2S="       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) g[ 0<m#"       GetConic eID, entity, curv, conic )0vU  k   7'-Lp@an       SetConic eID, entity, 1/Rant, CCant r)9Dy,       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant PjT=$]   -!;l~#K=       '************************************************************************* @l1       'Radius and conic constant of posterior lens E9|eu\       '************************************************************************* GuZ( &G6*       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) *%w69#D       GetConic eID, entity, curv, conic (bOpV>\Q7   +MbIB&fRCB       SetConic eID, entity, 1/Rpost, CCpost ,:fl?x.X       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost \;-fi.Hrf$   QVF]Ci_=       '************************************************************************* g*)K/Z0pJ$       'Lens thickness (Position of posterior lens surface) I$NhXZ)KT       '************************************************************************* R+q"_90_   {8,<ZZ_       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) )#a[-.OI   6iEhsL&K       ' Delete any z-shift(s) & gJV{V5Ay       count = 0 `b8v1Os^2       While GetOperationCount(eID)>count f\+fo           GetOperation eID, count, op ~U(,TjJb           If op.Type="ShiftZ" Then L@75-T               DeleteOperation eID,count ONNpiK-               count=count-1 di)*-+           End If d_n7k g+           count=count+1 lZ8CY       Wend  rhpPCt   g~7Ri-"       'Set new z-shift yc2/~a_Gx       op.Type = "ShiftZ" 4L-:*b_v\       op.val1 = tlens ,\ 2a=Fp       op.parent = parID D'Z|}(d&       AddOperation eID, op ,*4p?|A       Print "Set lens thickness = " & tlens {7!UQrm<   Am8x74?       '************************************************************************* aK,z}l(N       'Lens index of refraction `c/*H29       '************************************************************************* ;fw1       eID = FindMaterial( "Lens" ) x}U8zt)yD3       GetModelMaterial eID, mat *5zrZ]^   "fg](Cp[z       mat.Nd = nlens VIP7OHJh       SetModelMaterial eID, mat EFpIp4_Y       Print "Set lens index of refraction = " & nlens =X?\MVWB   SVjl~U-^       '************************************************************************* HL/bS/KX       'Pupil diameter 1h*)@       '************************************************************************* "#v=IJy&r       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) #`GY}-hL!   ^8 ' sib       'Adjust pupil diameter (trimming volume inner hole) V`adWXu   $^&ig       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" P5lqSA{6   iv phlw       ' Adjust pupil location to just in front of the lens ^:9 $@+a       parID = FindFullName( "Geometry.Arizona Eye" ) >0{S       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Lokl2o`       count = 0 < RCLI|       While GetOperationCount(eID)>count IHgeQ F ~           GetOperation eID, count, op }SIGPVM           If op.Type="ShiftZ" Then }M1sksk5               DeleteOperation eID,count bs9aE<j               count=count-1 e*+FpW@           End If o!:8nXw           count=count+1 p8 s:g~ W       Wend Z/^  u       op.Type = "ShiftZ" 1!pa;$L       op.val1 = taq-0.01 7_2k DDW0       op.parent = parID zEZLKWm9-       AddOperation eID, op fN"(mW>!   SXao|{?O       Print "Set pupil diameter = " & pupilDiam ZVeaTK4_ t   64-#}3zL       'Update AZ Eye subassembly Description 9h/>QLx       eID = FindFullName( "Geometry.Arizona Eye" ) x8 ;`i$       GetEntity eID, entity q1E:l!2al       entity.Description = "Accommodation = " & A & "D" 3] 1-M       SetEntity eID, entity "EU{8b   X(jVRr_m9       Update ) 'j:       Print "DONE!" 'qdPw%d        K[chjp!$l   End Sub ogFKUD*h&>   9Lh|DK,nV/   如果屈光度是4，光瞳直径是4，则会输出如下数据： UpXz&k   2oJb)CB   Accommodation = 4 Diopters v^ d]rSm   Pupil Diameter = 4 mm e!fqXVEVR   Set aqueous humor thickness = 2.81 y*{Zbz#{   Set anterior lens radius = 10.4 and conic constant = -2.375869 DO7W}WU   Set posterior lens radius = -4.424557 and conic constant = -3.081019 ,G#.BLH cX   Set lens thickness = 3.927 ?PTk1sB   Set lens index of refraction = 1.42672 y2O4I'/5<   Set pupil diameter = 4 |*RYq2y   DONE!

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