[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： y<0RgG1qp  
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RPC Photonics公司有高品质的的工程漫射体BSDF测试数据，但它对于FRED帮助甚少，下面这个步骤描述了如何利用FRED脚本转换RPC Photonics提供的TXT文件，并将数据直接应用到FRED的Tabulated scatter 散射模型。 (h$[g"8  
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背景：
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Thorlabs和RPC Photonics联手共同推出的新型漫射体及光束整形技术，可以解决其他技术的不足，大大改善了诸如光刻系统、有效固态照明，显示，背光，显示亮度增强和投影屏等大多数应用的性能。这项我们称之为工程漫射体（Engineered DiffusersTM）的新概念，与其他技术有许多不同。与诸如磨砂玻璃、乳色玻璃和全息元件等随机漫射体截然不同，工程漫射体要求对于每个散射中心，通常为微透镜单元，都进行控制。例如全息漫射体可以视为一组随机排列的透镜，但是通过全息曝光形成的类透镜效果只能通过静态方式进行控制：而无法单独操控每个微透镜单元，这也帮助解释了全息漫射体无法控制光的分布和轮廓。另一方面，在工程漫射体中，每个微透镜单元形成漫射体，由其凹形纵断面和在阵列中的位置所确定。同时，为了确保漫射体不受输入光束变化的影响，并且不产生衍射效果，微透镜单元的分布是随机的，根据产生相应的光束形状函数所选取的概率分布函数来确定。因此，工程漫射体同时保留了随机与确定性漫射体的优点，从而实现高性能的光束整形功能。 {!]7=K)W9  
FRED是美国Photon Engineering 公司开发的光学工程仿真软件，其在杂散光分析中独特的算法、高效的准确性，使其与其它同类产品相比更具优势。本案例我们重点讲述如何由RPC Photonics的BSDF数据转为FRED可识别的散射数据。 -rXo}I,VI  
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步骤 E,EpzB$_dj  
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1、 在http://www.rpcphotonics.com/bsdf-data-optical-diffusers/下载并解压BSDF数据到某一文件夹下，选择“Raw data”文件。 "gQA|NHwV  
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2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） u ^}R]:n  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 IJzPWs5W:  
例如下所示： Dc;zgLLL  
Sample name:  EDF-C1-56 2nsW)bd  
Merging data from file EDF-C1-56 0-0.txt -NuRf#  
Finished merging RPC data for sample EDF-C1-56 z(
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FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt !c#~g0H+  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 sY*iR
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a. 创建一个新的散射库 @b2JR^  
b. 散射模型命名 q(iM=IeiN  
c. 改变散射模型为“Tabulated BSDF”. aH(B}wh{  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） Zwm2T3@e
 
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 d4[mR~XXT  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， %"{jNC?  
g. 点击OK 4y$tp18  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 hnD=DLW $  
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脚本代码： O77bm,E  
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'#Language "WWB-COM" 1w|C+m/(  
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Option Explicit KMo]J1o  
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Sub Main |^!  
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    'Cleanup /Q*o6Gys0  
    ClearOutputWindow() CQGq}.Jt!  
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    Print "Merging RPC Photonics BSDF Data Files" Yj-JB  
    SetTextColor(255,0,0) b?Zt3#  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." h:qt?$]J  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." @UgZZ  
    SetTextColor(0,0,0) F\lnG  
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    'Current directory of this script (should be the same as the text files being merged) |?=a84n1l  
    Dim cDir As String "jFRGgd79  
    cDir = MacroDir$ & "\" :e|[gEA  
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    'Array which will be populated with the list of files to be merged P_{jZ}y(  
    Dim fList() As String, curFile As String S>y(3E]I  
    GetFileList( cDir, fList ) w4UaWT1J  
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    Print "" 8;vpa*  
    Print "Files found for merging:" J#OiY  
    For Each curFile In fList %%-hax.x0X  
        Print Chr(9) & curFile FdZG%N>Z  
    Next t^Hte^#S  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. &Fxw19[G  
    Dim nameArray() As String, sampName As String @jvF[wi;  
    nameArray = Split(fList(0)," 0-0.txt") Vu u2SS  
    sampName  = nameArray(0) iCK p"(kf  
    Print "" 5qx,b&^w  
    Print "Sample name: " & Chr(9) & sampName fQtV-\Bc  
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    'Open an output file and write the FRED header data ^/k`URQ  
    Dim outFile As String YH%aPsi  
    outFile = cDir & sampName & "_FRED.txt" Sjogv  
    Open outFile For Output As #1 ) C?emTih  
    Print #1, "type bsdf_data" X9lh@`3  
    Print #1, "format angles=deg bsdf=value scale=1" ELlTR/NW  
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    'Loop the file list, skip the two header lines and write the remaining data to file $Bd13%>)  
    Dim lineArray() As String, curLine As Long G31??L:<  
    For Each curFile In fList 9w%|Nk>=>  
        Print "Merging data from file " & curFile 0d%p<c  
        ReadFile( cDir & curFile, lineArray ) 5,pKv  
        For curLine = 2 To UBound(lineArray) "gR W91 T  
            Print #1, lineArray(curLine) o,#[Se*n  
        Next r-ldqj  
    Next
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    'Close the output file Hvm+Tr2@  
    Close #1 :tv:46+s=  
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    Print "Finished merging RPC data for sample " & sampName Mk*&CNo3  
    Print "FRED formatted data file: " & Chr(9) & outFile 7d7"^M  
End Sub N<xf=a+j  
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'Utility function to read the contents of a file into an array of strings.
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Function ReadFile(ByVal fileName As String, _ X>n\@rTo  
                  ByRef lineArray() As String) As Long 31w9$H N  
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    ReadFile = -1 &IQp&  
    Dim oFSO As Object @aG1PG{  
    Set oFSO = CreateObject("Scripting.FileSystemObject") 6~ *w~U  
    Erase lineArray 8-N8v *0  
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    Dim fid As Long b6IYo!3  
    If oFSO.fileexists( fileName ) Then 6,"fH{Bd  
        fid = FreeFile() C] <K s  
        Open fileName For Input As fid ;CU<\  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) _]"5]c&*3  
        Close fid ?fog 34g  
    End If [<)/ c>Y  
    Set oFSO = Nothing ?|8QL9Q"|  
    Return UBound( lineArray ) n7RswX  
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End Function `laaT5G\y  
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Sub GetFileList( ByVal in_dir As String, _ rpsq.n  
                 ByRef in_flist() As String ) \*}JdEHB  
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    'Redimension the file list array f>)k<-<yj  
    Erase in_flist |x|#n  
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    'Tracks how many files are found ^|@t2Rp@  
    Dim fCount As Long .Od.lxz"mp  
    fCount = 0 +/60$60[z  
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    'Recurse directory and search for text files }2Y:#{m  
    Dim f As String +'abAST t  
    f = Dir$(in_dir & "*.txt") a3i4eGT-  
    While f <> "" {n8mE,;M  
        ReDim Preserve in_flist(fCount) SI=vA\e  
        in_flist(fCount) = f f&glY`s#  
        fCount += 1 * B!uYP  
        f = Dir$() ]}2+yK  
    Wend gF;i3OJg  
    ReDim Preserve in_flist(fCount-1) K!6k<  
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End Sub )CQ'kHT<e