Arizona眼睛模型

$k?L?R1   人眼光学模型可用来设计眼科用设备，光学系统注定了要与人眼一起使用。本文演示了这样一个模型：Arizona眼睛模型，在Jim Schwiegerling教授的书中有详细描述：《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源，并包括一个基于想要的屈光度来调整模型的内嵌脚本。 QRjt.Ry|   #}Cwn$   模型 %)e+ w+   th<]L<BP/   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。 ) jvkwC   Table 1. AZ眼睛模型的定义 aD^MoB3   Qi}LV"&L   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. _aGdC8%[   r6)1Y`K=9   光源 .G]# _U   IY:O?M   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。 +OmSR*fA0   uj@<_|7   图1. 光源和提示信息使用 {MtB!x   WWLVy(   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。 #+G2ZJxL|   n\YxRs7 hF   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。 Ss:,#|    图2. 字母F光源的设定方法光 Ed-gYL^<   ^m=%C tu#   图3. 字母F在视网膜上位置点列图 [:'n+D=T3M   Hn~1x'$   视网膜的散射 YMd&+J`   $^!w`>0C   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 QhUraZ   7y\g~?5N   图4. 视网膜朗伯散射设定 <7^~r(DP   bij?q\   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 &^H "T6   QFPx4F7(e   图5. 视网膜重点采样规格设定 B`aAvD`7   U VKN#"_{   脚本 >C[1@-]G%7   * 2%e.d3"M   内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： u2<h<}Y   图6. 用户对话框的创建与编辑 dWy1=UQfP   图7. 用户对话框编辑器 4QNR_w    C":\L>Ax   如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 mmL~`i/   余下的脚本计算与屈光度有关的所有参数。 clw91yrQn   ^Q>*f/.KN   分析 ArYF\7P   Y,yaB)&Ih   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 DeA'D|   图7. 字母F在视网膜上颜色分析 B6\VxSX4{   P{eR DQ=   脚本代码 EC'bgFe   ai4^NJn   Option Explicit     'Remove this to enable non-dimensioned variables to be used. c!Vc_@V,   m!60.   Dim entity As T_ENTITY MF}Lv1/[-J   Dim op As T_OPERATION Xb*_LZAU   Dim mat As T_MODELMATERIAL kVnyX@   Dim A As Double l|A8AuO*?   Dim pupilDiam As Double sjgR \`AU   Dim eID As Long }!V<"d,!   Dim parID As Long :, [!8QP   Dim count As Integer +3>/,w(x   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double z|*6fFE    Dim tlens As Double, nlens As Double 3 ?F@jEQk   Dim curv As Double, conic As Double +c`C9RXk   Dim ok As Long IGT_ 5te   p,\bez   Sub Main Q+(:n)G_6E   F M"BTA:C       '用户输入对话框 lO> 7`2x=F       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 -Y?(Zz_w           TextBox 220,21,40,21,.TextBox1 'default: 0 T1 HiHvJ           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 o%PoSZZ           OKButton 40,91,90,21 +A?+G           CancelButton 190,91,90,21 ws>Iyw.u           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 sFCs_u1tNN           TextBox 220,49,40,21,.TextBox2 'default: 4 I%>]!X       End Dialog H)T# R?       Dim dlg As UserDialog BC{J3<0bf@   C$G88hesn       ok = Dialog (dlg) [e@OHQM   `OReSg 2       If ok=0 Then    'cancel button was pressed h$ iyclX           Print "Execution cancelled." _8pkejg           End ;To+,`?E;q       End If ":#x\;   dzNaow*0&V       'Assign accommodation and pupil diameter & use defaults if field left empty Z?v6pjZ?       If dlg.TextBox1 = "" Then A|_%'8           A = 0           'Default accommodation ; 9&.QR(       Else {R!TUQ5           A = CDbl(dlg.TextBox1) 0* IY%=i       End If V'f5-E0   B m@oB2x)       If dlg.TextBox2 = "" Then 'a/6]%QFd!           pupilDiam = 4   'Default pupil diameter zHc4e        Else b;`#Sea           pupilDiam = CDbl(dlg.TextBox2) ?Gv!d       End If $_7d! S"   $4*E\G8       Print " " &Yks,2:P       Print "Accommodation = " & A & " Diopters" d>b,aj(       Print "Pupil Diameter = " & pupilDiam & " mm" P}WhE   xVz -_z       ' Calculate new parameters with accommodation >`?+FDOJ,       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness b, **$   p C2c(4       Rant = 12.0 - 0.4*A                     'Radius of anterior lens \ NSw<.       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens -KJ!   ah"MzU)       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 8j+:s\       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens I;.! hV>E   @uM3iO7&       tlens = 3.767 + 0.04*A                  'Lens thickness t"bPKFRy9E   (zro7gKked       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction yH"$t/cU"R    `_g?y)       'Adjust parameters to account for accommodation >-|90CSdSJ   U>B5LU9&       '************************************************************************* &~JfDe9IS       'Aqueous thickness (Position of Lens) ywQ!9 \       '************************************************************************* D7_Hu'y<o       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) IU'!?XVo       GetCustomElement eID, entity zTBi{KrZ   {Fp`l\,       parID = FindFullName( "Geometry.Arizona Eye" ) Vh.;p.!e   ;$tv8%_L[       ' Delete any shift(s) in z 3{I=#>;       count = 0 D.&eM4MZ       While GetOperationCount(eID)>count $7gB&T.x           GetOperation eID, count, op ,ORG"]_F           If op.Type="ShiftZ" Then >]XaUQ-               DeleteOperation eID,count HSr"M.k5               count=count-1 77&^$JpM           End If &(uF&-PwO4           count=count+1 xlPcg7       Wend vrm{Ql&   N}x/&e       'Set new shift in ",aT<lw.       op.Type = "ShiftZ" ! N"L`RWD       op.val1 = taq @a.6?.<L       op.parent = parID Xv7U< q       AddOperation eID, op }2BH_  2       Print "Set aqueous humor thickness = " & taq-0.55 $kD`$L@U   F3Ak'h{Ay       '*************************************************************************   fBWJ%W       'Radius and conic constant of anterior lens _^xh1=Qr}n       '************************************************************************* JX\T {\m#       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) +%le/Pg@       GetConic eID, entity, curv, conic nzE,F\k   {7Gx9(       SetConic eID, entity, 1/Rant, CCant x,w`OMQ}c       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant \{MrQ2jd   2NArE@       '************************************************************************* VNxpOoV=S       'Radius and conic constant of posterior lens Lr24bv \       '************************************************************************* \Sq"3_m4T       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) @cS1w'=       GetConic eID, entity, curv, conic we H@S   94'k7_q       SetConic eID, entity, 1/Rpost, CCpost mS)|6=Y       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost =ve*g&   lEyG9Xvi       '************************************************************************* q(jkit~`A       'Lens thickness (Position of posterior lens surface) 9#EHXgz       '************************************************************************* ,3J`ftCV   h[-d1bKwS       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) x8pbO[_|   bU:}ZO^S       ' Delete any z-shift(s) P+;CE|J`X       count = 0 I", &%0ycm       While GetOperationCount(eID)>count M~ i+F0           GetOperation eID, count, op !HdvCYB>           If op.Type="ShiftZ" Then O7'<I|aD               DeleteOperation eID,count /.|A               count=count-1 6HEqm>Yau           End If ;Txv-lfS           count=count+1 u^aFj%}]L       Wend KTLbqSS\   ?2?S[\@`0U       'Set new z-shift ]M+VSU       op.Type = "ShiftZ" v ]/OAH6D       op.val1 = tlens !y qa?\v9       op.parent = parID S/nj5Lh       AddOperation eID, op O2`oe4."vd       Print "Set lens thickness = " & tlens jSwtf   Xx3g3P       '************************************************************************* |b$>68:       'Lens index of refraction \uU=O )       '************************************************************************* XSm"I[.g       eID = FindMaterial( "Lens" ) tT@w%Sz57N       GetModelMaterial eID, mat [5?4c'Ev   fr}1_0DDz       mat.Nd = nlens ()QOZ+x_!       SetModelMaterial eID, mat =9qGEkd3       Print "Set lens index of refraction = " & nlens M#\ <   %1-K);SJ       '************************************************************************* c-4m8Kg?L       'Pupil diameter Snc; p       '************************************************************************* | ((1V^       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) mQd4#LJ_   ]>R`;"(       'Adjust pupil diameter (trimming volume inner hole) P"(z jG9-   KGV.S       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" >63)z I   f7XQ~b       ' Adjust pupil location to just in front of the lens u*t, i`       parID = FindFullName( "Geometry.Arizona Eye" ) S=0"f}Jo.       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) mR{CVU       count = 0 nS_Ta       While GetOperationCount(eID)>count !_CX2|           GetOperation eID, count, op YCa@R!M*O           If op.Type="ShiftZ" Then ]pW86L%               DeleteOperation eID,count H~A"C'P3#               count=count-1 ?M*7@t@           End If NFk}3w :           count=count+1 =N YgGEFq.       Wend 8YuJ8KC       op.Type = "ShiftZ" :ozV3`%$(       op.val1 = taq-0.01 uije#cj#O       op.parent = parID LHs-&       AddOperation eID, op 2\^G['9   Z[",$Lt       Print "Set pupil diameter = " & pupilDiam e^j<jV`1   R/^@ cA       'Update AZ Eye subassembly Description WtEI] WO       eID = FindFullName( "Geometry.Arizona Eye" ) ?b||Cr       GetEntity eID, entity rRB~=J"       entity.Description = "Accommodation = " & A & "D" >[ eW">:>K       SetEntity eID, entity KAd_zkUA   ]UDd :2yt       Update 10p8|9rE}B       Print "DONE!" 6X/wdk        "jMqt9ysN   End Sub 7ftR4   Pm4e8b   如果屈光度是4，光瞳直径是4，则会输出如下数据： H&M1>JtE   t/}L36@+   Accommodation = 4 Diopters (+* ][|T   Pupil Diameter = 4 mm >lrhHU   Set aqueous humor thickness = 2.81 > 2#%$lX6   Set anterior lens radius = 10.4 and conic constant = -2.375869 93j{.0]X   Set posterior lens radius = -4.424557 and conic constant = -3.081019 8{dEpV*   Set lens thickness = 3.927 !O|ql6^;   Set lens index of refraction = 1.42672 v ?L   Set pupil diameter = 4 ZWO)tVw9G   DONE!

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