[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： yD(0:g#  
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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。 s9zdg"c'  
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背景： PKty'}
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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。 E XEae?  
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。 c"v#d9  
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步骤 .^fq$7Y}7  
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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。 x/R|i%u-s  
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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） r. =_=V/t  
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 Cir==7A0  
例如下所示： JIQS'
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Sample name:  EDF-C1-56 ;N6L`|  
Merging data from file EDF-C1-56 0-0.txt zH.DyD5T;  
Finished merging RPC data for sample EDF-C1-56 \|L@  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt n
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4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 ym{?vY h  
a. 创建一个新的散射库 P BpjE}[Q  
b. 散射模型命名 NyFa2Ihd  
c. 改变散射模型为“Tabulated BSDF”.
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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 ） &1{RuV
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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。 Nj@k|_1
 
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， ==l p\  
g. 点击OK .TSj8,  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 ;Z%ysLA  
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脚本代码： #db8ur3?  
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'#Language "WWB-COM" o5-oQ_j  
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Option Explicit =;9Wh!{  
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Sub Main i-vhX4:bd  
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    'Cleanup XTUxMdN  
    ClearOutputWindow() *1$rg?yGf  
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    Print "Merging RPC Photonics BSDF Data Files" O$V 6QJ  
    SetTextColor(255,0,0) W7c(] tg.  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." ICN>8|O`&  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." 7%c9 nY  
    SetTextColor(0,0,0) By]XD~gcP  
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    'Current directory of this script (should be the same as the text files being merged) ><mZOTn e;  
    Dim cDir As String FVPhk2  
    cDir = MacroDir$ & "\" |<96H8  
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    'Array which will be populated with the list of files to be merged 47ppyh6@  
    Dim fList() As String, curFile As String S#8wnHq  
    GetFileList( cDir, fList ) ),(ejRP'r  
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    Print "" EW%%W6O6  
    Print "Files found for merging:" `(vgBz`e[  
    For Each curFile In fList <UQaRI[55  
        Print Chr(9) & curFile  Jx9S@L`  
    Next +ByxhSIr  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. (\{9W  
    Dim nameArray() As String, sampName As String B$1e AwT9  
    nameArray = Split(fList(0)," 0-0.txt") o3P`y:&  
    sampName  = nameArray(0)
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    Print "" F#Uxl%h  
    Print "Sample name: " & Chr(9) & sampName O8(;=exA  
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    'Open an output file and write the FRED header data *6sB$E_y  
    Dim outFile As String 9$c0<~B\  
    outFile = cDir & sampName & "_FRED.txt" UTGR{>=>  
    Open outFile For Output As #1 bg[k8*.:F  
    Print #1, "type bsdf_data" *91iFeKj=  
    Print #1, "format angles=deg bsdf=value scale=1" j0B, \A  
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    'Loop the file list, skip the two header lines and write the remaining data to file BG_m}3j  
    Dim lineArray() As String, curLine As Long z6#N f,  
    For Each curFile In fList uc<XdFcu  
        Print "Merging data from file " & curFile 6Xb\a^q  
        ReadFile( cDir & curFile, lineArray )
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        For curLine = 2 To UBound(lineArray) FY)vrM*yh  
            Print #1, lineArray(curLine) D|/Azy.[  
        Next "aHY]E{  
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    'Close the output file yw^t6E  
    Close #1 %Qgo0  
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    Print "Finished merging RPC data for sample " & sampName k!H;(B"s-  
    Print "FRED formatted data file: " & Chr(9) & outFile _6Wz1.]n  
End Sub @+h2R  
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'Utility function to read the contents of a file into an array of strings. QMea2q|3$  
Function ReadFile(ByVal fileName As String, _ g6o-/A!Q3  
                  ByRef lineArray() As String) As Long O6LZ<}oUR  
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    ReadFile = -1 {>tgNW>)  
    Dim oFSO As Object ]|18tVXc  
    Set oFSO = CreateObject("Scripting.FileSystemObject") _m;0%]+  
    Erase lineArray %Js3Y9AL C  
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    Dim fid As Long ;ZPAnd:pb  
    If oFSO.fileexists( fileName ) Then o\vIYQ   
        fid = FreeFile() Un@B D}@\  
        Open fileName For Input As fid %Ez%pT0TQ#  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) e.hHpjWi?Z  
        Close fid uNZJNrV%  
    End If QFU;\H/  
    Set oFSO = Nothing *q_ .y\D  
    Return UBound( lineArray ) y K)7%j!  
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End Function ]Cnj=\'  
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Sub GetFileList( ByVal in_dir As String, _ gm~Ka%O|F  
                 ByRef in_flist() As String ) zD}dvI}  
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    'Redimension the file list array  Q<B=m6~  
    Erase in_flist fT [JU1  
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    'Tracks how many files are found YqX/7b+  
    Dim fCount As Long |VbF&*v`  
    fCount = 0 &:`T!n  
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    'Recurse directory and search for text files 8`XpcK-0  
    Dim f As String +C1/02ZJ  
    f = Dir$(in_dir & "*.txt") ^]o]'  
    While f <> "" W=41jw  
        ReDim Preserve in_flist(fCount) (.4mX t  
        in_flist(fCount) = f +Rn]6}5m\  
        fCount += 1 ; S7 %  
        f = Dir$() fQRGz\r*k  
    Wend ^dFdw\  
    ReDim Preserve in_flist(fCount-1) !:t}8  
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End Sub ,!_$A}@0 ^