[分享]RPC Photonics扩散片BSDF [复制链接]

摘要： 9ENI%Jz  
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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。 k SgE_W)  
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背景： 7O:g;UI#  
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。 (][-()YV  
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。 JW)f'r_f  
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步骤 yDWBrN._  
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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。 :
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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） ^bP`Iv  
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 BC\W`K  
例如下所示： WIuYSt)h  
Sample name:  EDF-C1-56 7?{y&sf  
Merging data from file EDF-C1-56 0-0.txt %V+"i_{m  
Finished merging RPC data for sample EDF-C1-56 SN]g4}K-  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt k>7bPR5Mw  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 }2iR=$2  
a. 创建一个新的散射库 oOC&w0  
b. 散射模型命名 7mf&`.C np  
c. 改变散射模型为“Tabulated BSDF”. >\w]i*%  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） 3 ^K#\*P  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 A^#\=ZBg1  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， /|<SD.:  
g. 点击OK 2ij&D
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5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 s]|tKQGl,  
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脚本代码： e([>sAx!1  
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'#Language "WWB-COM" Pq8oK'z-  
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Option Explicit |cgjn*a?M  
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Sub Main MtaGv#mJ  
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    'Cleanup
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    ClearOutputWindow() }z$_!)/i  
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    Print "Merging RPC Photonics BSDF Data Files" G"OP`OMDc  
    SetTextColor(255,0,0) I:G8
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    Print "Note: Script should be located in the same folder as the BSDF TXT files." @c'iT20  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." /I!62?)-*  
    SetTextColor(0,0,0) Bv!{V)$  
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    'Current directory of this script (should be the same as the text files being merged) CbC[aVA=  
    Dim cDir As String 2l+L96  
    cDir = MacroDir$ & "\" y<6c*e1  
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    'Array which will be populated with the list of files to be merged kLF`6ZXtd  
    Dim fList() As String, curFile As String M\a{2f7'n  
    GetFileList( cDir, fList ) v_Sa0
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    Print "" PfRA\  
    Print "Files found for merging:" EJ#I7_  
    For Each curFile In fList ]& ckq  
        Print Chr(9) & curFile mL
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    Next rDhQ3iCqo  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. \fiy[W/k  
    Dim nameArray() As String, sampName As String ^4+NPk  
    nameArray = Split(fList(0)," 0-0.txt") U4fv$gV  
    sampName  = nameArray(0) dk nM|  
    Print "" J8p;1-C"  
    Print "Sample name: " & Chr(9) & sampName n:O
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    'Open an output file and write the FRED header data 'ia-h7QWS  
    Dim outFile As String GEF's#YWK  
    outFile = cDir & sampName & "_FRED.txt" t;6<k7h  
    Open outFile For Output As #1 b4-gNF]Yt  
    Print #1, "type bsdf_data" <)wLxWalF  
    Print #1, "format angles=deg bsdf=value scale=1" `G1"&q,i  
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    'Loop the file list, skip the two header lines and write the remaining data to file @n?"*B  
    Dim lineArray() As String, curLine As Long m+;U,[%[*E  
    For Each curFile In fList jVd`J  
        Print "Merging data from file " & curFile *3fl}l  
        ReadFile( cDir & curFile, lineArray ) [0y,K{8t  
        For curLine = 2 To UBound(lineArray) Zf3(! a[  
            Print #1, lineArray(curLine) *3`R W<Z  
        Next :_6o|9J\t  
    Next Os'E7;:1h  
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    'Close the output file cM'MgX9  
    Close #1 hdx_Tduue  
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    Print "Finished merging RPC data for sample " & sampName {l,&F+W$C  
    Print "FRED formatted data file: " & Chr(9) & outFile tj~r>SRb+  
End Sub rIPfO'T?  
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'Utility function to read the contents of a file into an array of strings. 2|lR@L sr  
Function ReadFile(ByVal fileName As String, _ 2PyuM=(Wt  
                  ByRef lineArray() As String) As Long +bLP+]7oZ  
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    ReadFile = -1 Rf8Obk<  
    Dim oFSO As Object En9J7es_  
    Set oFSO = CreateObject("Scripting.FileSystemObject") y EfAa6  
    Erase lineArray NMK$$0U  
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    Dim fid As Long ~6kF`}5  
    If oFSO.fileexists( fileName ) Then e8("G[P>  
        fid = FreeFile() PL&>pM  
        Open fileName For Input As fid \Hrcf+`  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) ,]wQ]fpt  
        Close fid oQ r.cKD ?  
    End If \99'#]\_/E  
    Set oFSO = Nothing Ebs]]a>PO  
    Return UBound( lineArray ) xjbI1qCfe  
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End Function 2~f*o^%l  
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Sub GetFileList( ByVal in_dir As String, _ #rX^)2  
                 ByRef in_flist() As String ) onSt%5{P%X  
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    'Redimension the file list array KJoa^e;~  
    Erase in_flist `)y ;7%-  
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    'Tracks how many files are found W`
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    Dim fCount As Long C;HEvq7  
    fCount = 0 6AJ`)8HX  
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    'Recurse directory and search for text files I2CI9,0  
    Dim f As String YQC.jnb2  
    f = Dir$(in_dir & "*.txt") )yb~ k
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    While f <> "" z_xy*Iif  
        ReDim Preserve in_flist(fCount) iu=Mq|t0  
        in_flist(fCount) = f 5l8F.LtO\  
        fCount += 1 w}l^B>Zz  
        f = Dir$() rhPv{6Z|7  
    Wend cQ-#]  
    ReDim Preserve in_flist(fCount-1) 153*b^iDBh  
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End Sub u-iQ  
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