[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： u(Sz$eV  
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RPC Photonics公司有高品质的的工程漫射体BSDF测试数据，但它对于FRED帮助甚少，下面这个步骤描述了如何利用FRED脚本转换RPC Photonics提供的TXT文件，并将数据直接应用到FRED的Tabulated scatter 散射模型。 mm-UQ\h  
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背景： ha! "BR  
Thorlabs和RPC Photonics联手共同推出的新型漫射体及光束整形技术，可以解决其他技术的不足，大大改善了诸如光刻系统、有效固态照明，显示，背光，显示亮度增强和投影屏等大多数应用的性能。这项我们称之为工程漫射体（Engineered DiffusersTM）的新概念，与其他技术有许多不同。与诸如磨砂玻璃、乳色玻璃和全息元件等随机漫射体截然不同，工程漫射体要求对于每个散射中心，通常为微透镜单元，都进行控制。例如全息漫射体可以视为一组随机排列的透镜，但是通过全息曝光形成的类透镜效果只能通过静态方式进行控制：而无法单独操控每个微透镜单元，这也帮助解释了全息漫射体无法控制光的分布和轮廓。另一方面，在工程漫射体中，每个微透镜单元形成漫射体，由其凹形纵断面和在阵列中的位置所确定。同时，为了确保漫射体不受输入光束变化的影响，并且不产生衍射效果，微透镜单元的分布是随机的，根据产生相应的光束形状函数所选取的概率分布函数来确定。因此，工程漫射体同时保留了随机与确定性漫射体的优点，从而实现高性能的光束整形功能。 ok2~B._+;  
FRED是美国Photon Engineering 公司开发的光学工程仿真软件，其在杂散光分析中独特的算法、高效的准确性，使其与其它同类产品相比更具优势。本案例我们重点讲述如何由RPC Photonics的BSDF数据转为FRED可识别的散射数据。 S5KYZ W  
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步骤 O f@#VZ  
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1、 在http://www.rpcphotonics.com/bsdf-data-optical-diffusers/下载并解压BSDF数据到某一文件夹下，选择“Raw data”文件。 lkg*AAR?'  
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2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） .{a2z*o  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 ]\,uF8gg)  
例如下所示： ko2j|*D6@~  
Sample name:  EDF-C1-56 F(~_L.  
Merging data from file EDF-C1-56 0-0.txt A=d$ir K[  
Finished merging RPC data for sample EDF-C1-56 |;m`874  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt dHF$T33It  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 $YY)g$  
a. 创建一个新的散射库 Y*cJ4hQ  
b. 散射模型命名 M03i4R@h(  
c. 改变散射模型为“Tabulated BSDF”. #x@lZ!Y  
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 ） \R\@t]>Y  
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"Y?y:!  
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， uE#,c\[8  
g. 点击OK t`YZ)
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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 JOx,19r  
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脚本代码： =Z .V+4+  
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'#Language "WWB-COM" ,,gLrVk  
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Option Explicit 66@3$P%1p  
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Sub Main A:bPIXb  
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    'Cleanup =ch Af=  
    ClearOutputWindow() o;4e)tK  
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    Print "Merging RPC Photonics BSDF Data Files" \btR^;_\A  
    SetTextColor(255,0,0) ,mjfZ*N  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." "R2t&X[9  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." q X%vRf0  
    SetTextColor(0,0,0) vV6Lp  
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    'Current directory of this script (should be the same as the text files being merged) q bZ,K@0  
    Dim cDir As String YP#AB]2\}  
    cDir = MacroDir$ & "\" |[owNV>  
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    'Array which will be populated with the list of files to be merged H8-D'q>R  
    Dim fList() As String, curFile As String nJ
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    GetFileList( cDir, fList ) _
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    Print "" |v$%V#Bo  
    Print "Files found for merging:" Xm8Z+}i  
    For Each curFile In fList ~i }+P71  
        Print Chr(9) & curFile RJRq` T|m  
    Next y^!E "  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. 3cCK"kr  
    Dim nameArray() As String, sampName As String `?]rr0.}hp  
    nameArray = Split(fList(0)," 0-0.txt") OS"{"P  
    sampName  = nameArray(0) vNz;#Je  
    Print "" vdH+>l  
    Print "Sample name: " & Chr(9) & sampName [EmOA.6  
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    'Open an output file and write the FRED header data p<HTJ0  
    Dim outFile As String aI={,\  
    outFile = cDir & sampName & "_FRED.txt" 7bonOt Y  
    Open outFile For Output As #1 Z\|u9DO  
    Print #1, "type bsdf_data" WXLe,7y  
    Print #1, "format angles=deg bsdf=value scale=1" uS,p|}Q&  

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    'Loop the file list, skip the two header lines and write the remaining data to file A-a17}fta  
    Dim lineArray() As String, curLine As Long ~IlF*Zz#}6  
    For Each curFile In fList <o&o=Y8  
        Print "Merging data from file " & curFile h"u<E\g  
        ReadFile( cDir & curFile, lineArray ) q}<.x8\  
        For curLine = 2 To UBound(lineArray) JFG",09]  
            Print #1, lineArray(curLine) OB?SkR  
        Next 6.U"_%  
    Next QGH h;  
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    'Close the output file Ig1lol:;  
    Close #1 TsaW5ho<p  
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    Print "Finished merging RPC data for sample " & sampName qnq%mwDeD  
    Print "FRED formatted data file: " & Chr(9) & outFile 83KfM!w  
End Sub a[1sA12  
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'Utility function to read the contents of a file into an array of strings. /7k.r}6\R  
Function ReadFile(ByVal fileName As String, _ 1mJbQ#5  
                  ByRef lineArray() As String) As Long jDlA<1  
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    ReadFile = -1 JsmbW|t^  
    Dim oFSO As Object cT-K@dg  
    Set oFSO = CreateObject("Scripting.FileSystemObject") C9<4~IM w  
    Erase lineArray brg":V1a  
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    Dim fid As Long 1@A7h$1P  
    If oFSO.fileexists( fileName ) Then gB]C&Q  
        fid = FreeFile() e7@li<3>d  
        Open fileName For Input As fid jrm0@K+<IA  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) RVc)") hQj  
        Close fid ?^LG hdR   
    End If { EA2  
    Set oFSO = Nothing H
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    Return UBound( lineArray ) $brKl8P  
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End Function f%2%T'Q  
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Sub GetFileList( ByVal in_dir As String, _ [J~aAB  
                 ByRef in_flist() As String ) C/F@ ]_y  
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    'Redimension the file list array P?^JPbfV  
    Erase in_flist fO*)LPen.z  
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    'Tracks how many files are found saatU;V  
    Dim fCount As Long oG!6}5  
    fCount = 0 '.pgXsC:=?  
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    'Recurse directory and search for text files ,# ]+HS^B  
    Dim f As String e\`wlaP,  
    f = Dir$(in_dir & "*.txt") {3_Gjb5\\4  
    While f <> "" avlqDi1l  
        ReDim Preserve in_flist(fCount) St
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        in_flist(fCount) = f x@htx?  
        fCount += 1 9*' &5F=  
        f = Dir$() P"b8!k?  
    Wend 8Bq-0=E  
    ReDim Preserve in_flist(fCount-1) iBucT"d]  
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End Sub d$}&nV/A)