[分享]RPC Photonics扩散片BSDF [复制链接]

摘要： EX`"z(L  
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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。 Qqd6.F  
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背景： +R|U4`12  
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。 8q]J;T
  
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。 |ZvNH ~!  
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步骤 DRH'A!r!  
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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。 Cw 1 9y  
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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） J__;.rnk  
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 .qSBh hH\  
例如下所示： V
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Sample name:  EDF-C1-56 ~_'0]P\  
Merging data from file EDF-C1-56 0-0.txt }KK2WJp#M  
Finished merging RPC data for sample EDF-C1-56 PKi_Zh.D  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt kt:)W])V  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 %moJF1  
a. 创建一个新的散射库 'nMApPl  
b. 散射模型命名 O~.U:45t  
c. 改变散射模型为“Tabulated BSDF”. U);OR  
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 ） {T&v2u#S  
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。 fGb7=Fk  
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， Xad*Iulj  
g. 点击OK #e*X0;m  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 H6_xwuw:  
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脚本代码： Wdo#?@m  
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'#Language "WWB-COM" )7W6-.d  
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Option Explicit F<5nGx cC  
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Sub Main |=\91fP68`  
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    'Cleanup F+Z2U/'a  
    ClearOutputWindow() Rvvh{U;t  
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    Print "Merging RPC Photonics BSDF Data Files" cS}r9gaQ  
    SetTextColor(255,0,0) [G
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    Print "Note: Script should be located in the same folder as the BSDF TXT files." sMH#BCC  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." @&5A&(  
    SetTextColor(0,0,0) VpSEVd:n  

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    'Current directory of this script (should be the same as the text files being merged) |1"!kA  
    Dim cDir As String W}h|K:-S  
    cDir = MacroDir$ & "\" _S"f_W  
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    'Array which will be populated with the list of files to be merged |q_ !. a  
    Dim fList() As String, curFile As String a}>Dz 1R  
    GetFileList( cDir, fList ) ]ZTcOf  
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    Print "" g]|_ `  
    Print "Files found for merging:" azo0{`S?  
    For Each curFile In fList _R7 w?!t8  
        Print Chr(9) & curFile k(v
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    Next O%-h&C3  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. uUG*0Lj  
    Dim nameArray() As String, sampName As String Y
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    nameArray = Split(fList(0)," 0-0.txt") F6W}mMZH/N  
    sampName  = nameArray(0) x l0DN{PG  
    Print "" J{Tq%\a3  
    Print "Sample name: " & Chr(9) & sampName f7J,&<<5w  
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    'Open an output file and write the FRED header data `U{mbw,  
    Dim outFile As String !8*McOI  
    outFile = cDir & sampName & "_FRED.txt" B wC+o
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    Open outFile For Output As #1 `5'2Hg+  
    Print #1, "type bsdf_data" m_*R.a  
    Print #1, "format angles=deg bsdf=value scale=1" ioV_oR9I  
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    'Loop the file list, skip the two header lines and write the remaining data to file kX[fy7rVt  
    Dim lineArray() As String, curLine As Long ~O: U|&  
    For Each curFile In fList '# z]M  
        Print "Merging data from file " & curFile %M&3VQ9w  
        ReadFile( cDir & curFile, lineArray ) Rg* J}  
        For curLine = 2 To UBound(lineArray) \cQ .|S  
            Print #1, lineArray(curLine) 5)'P'kVi7.  
        Next B8m_'!;;  
    Next =MLf[
 
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    'Close the output file ->E=&X  
    Close #1 @(:v_l  
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    Print "Finished merging RPC data for sample " & sampName ? _<[T  
    Print "FRED formatted data file: " & Chr(9) & outFile `qiQ$kz  
End Sub #SkX@sl@
 
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'Utility function to read the contents of a file into an array of strings. - 8bNQU  
Function ReadFile(ByVal fileName As String, _ :?CQuEv-  
                  ByRef lineArray() As String) As Long :gI.l1  
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    ReadFile = -1 [B^G-  
    Dim oFSO As Object !e3YnlE  
    Set oFSO = CreateObject("Scripting.FileSystemObject") wAYB RY[  
    Erase lineArray h qmSE'8  
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    Dim fid As Long KJh,,xI>by  
    If oFSO.fileexists( fileName ) Then XM~~y~j  
        fid = FreeFile() &uM^0eM  
        Open fileName For Input As fid t`|,6qEG  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) I,O#X)O|i  
        Close fid & ,L9OU  
    End If G'x 
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    Set oFSO = Nothing :b/jNHJU  
    Return UBound( lineArray ) [@"wd_f{l  
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End Function P<;7j?  
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Sub GetFileList( ByVal in_dir As String, _ nWWM2v  
                 ByRef in_flist() As String ) D59T?B|BdD  
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    'Redimension the file list array Ec]|p6a3  
    Erase in_flist cA;js;x@  
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    'Tracks how many files are found hu5!ev2  
    Dim fCount As Long ijUzC>O+q  
    fCount = 0 RT*5d;l0  
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    'Recurse directory and search for text files -5>NE35Cto  
    Dim f As String UUtbD&\  
    f = Dir$(in_dir & "*.txt") G&9#*<F$c  
    While f <> "" IA*KaX2S<  
        ReDim Preserve in_flist(fCount) ?o[L7JI  
        in_flist(fCount) = f MZv\ C  
        fCount += 1 S~F`  
        f = Dir$() p!W[X%`)  
    Wend )\0F7Z  
    ReDim Preserve in_flist(fCount-1) 9dKul,c  
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End Sub SR7j\1a/2A  
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