[技术]RPC Photonics扩散片BSDF [复制链接]

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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。 5 2Hqu>  
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背景： z+VV}:Q  
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。 rla:<6tt  
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。 h)dRR_  
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步骤 T\sNtdF`:  
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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。 I:;+n^N?  
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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） %$9bce-fcG  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 w|Q
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例如下所示： _z"o1`{w  
Sample name:  EDF-C1-56 P. V\ov7m2  
Merging data from file EDF-C1-56 0-0.txt ,"G\f1  
Finished merging RPC data for sample EDF-C1-56 uMiyq<  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt BKb<2  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 f=_g8+}h  
a. 创建一个新的散射库 !$>G#+y  
b. 散射模型命名 Yj8&  
c. 改变散射模型为“Tabulated BSDF”. 3,$iGe  
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 ） 04JT@s"o
 
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。 e\N0@  
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， o#{#r@,i  
g. 点击OK fusPMf *[  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 QJXdb]Y^;  
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脚本代码： r8v:|Q1"  
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'#Language "WWB-COM" JDhwN<0R  
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Option Explicit %b<%w   
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Sub Main x[Q&k[xV  
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    'Cleanup kI+b <$:D  
    ClearOutputWindow() shK&2Noan  
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    Print "Merging RPC Photonics BSDF Data Files" yJJ8"s~i  
    SetTextColor(255,0,0) k?-S`o%Q  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." i./Y w
 
    Print "Note: Do not run this script multiple times without deleting the output file between executions." /v$]X4 S`  
    SetTextColor(0,0,0) P^4'|#~2T  
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    'Current directory of this script (should be the same as the text files being merged)  N|N/)  
    Dim cDir As String p JX, n  
    cDir = MacroDir$ & "\" cVg$dt  
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    'Array which will be populated with the list of files to be merged K~JC\a\0  
    Dim fList() As String, curFile As String k4mTZ}6E  
    GetFileList( cDir, fList ) +/_!P;I  
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    Print "" W_D%|Ub2X  
    Print "Files found for merging:" ,O9`X6rh'  
    For Each curFile In fList STRyW Ml  
        Print Chr(9) & curFile d<?X3&J  
    Next x`3.Wu\  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. U]mO7HK  
    Dim nameArray() As String, sampName As String ;]u1
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    nameArray = Split(fList(0)," 0-0.txt") L]NYYP-  
    sampName  = nameArray(0) g4T3?"xMB_  
    Print "" |vT=Nnu  
    Print "Sample name: " & Chr(9) & sampName c0hdLl;5  
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    'Open an output file and write the FRED header data ]o!&2:'N`  
    Dim outFile As String J ZNyC!u  
    outFile = cDir & sampName & "_FRED.txt" b@F_7P%  
    Open outFile For Output As #1 $"(3MnR  
    Print #1, "type bsdf_data" /gF]s_
 
    Print #1, "format angles=deg bsdf=value scale=1" LA
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    'Loop the file list, skip the two header lines and write the remaining data to file -KA4Inn]5  
    Dim lineArray() As String, curLine As Long 14;Av{Xt  
    For Each curFile In fList BiI{8`M!$x  
        Print "Merging data from file " & curFile ":z@c,  
        ReadFile( cDir & curFile, lineArray ) uRs9}dzv  
        For curLine = 2 To UBound(lineArray) Ic_tc  
            Print #1, lineArray(curLine) Q!Msy<v  
        Next >4#tkv>S.  
    Next tTE3H_  
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    'Close the output file Mof)2Hbd:  
    Close #1 t2m
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    Print "Finished merging RPC data for sample " & sampName =7H.F:BBG  
    Print "FRED formatted data file: " & Chr(9) & outFile B0NN>)h  
End Sub $)Jc-V 6E  
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'Utility function to read the contents of a file into an array of strings. JO]`LF]  
Function ReadFile(ByVal fileName As String, _ e(4bx5<*  
                  ByRef lineArray() As String) As Long J
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    ReadFile = -1 !~Ax  
    Dim oFSO As Object zl,bMtQ  
    Set oFSO = CreateObject("Scripting.FileSystemObject") |ORmS&7  
    Erase lineArray he_HVRpB  
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    Dim fid As Long oR4fK td  
    If oFSO.fileexists( fileName ) Then  zd.1  
        fid = FreeFile() wV]sGHuF}  
        Open fileName For Input As fid ~mHXz  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) LAOdH/*:  
        Close fid !Q<8c =f  
    End If }D8~^  
    Set oFSO = Nothing xuw//F  
    Return UBound( lineArray ) _D!M nTK  
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End Function qYQUr8{  
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Sub GetFileList( ByVal in_dir As String, _ {[H4G,QK  
                 ByRef in_flist() As String ) ,dGFX]P  
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    'Redimension the file list array
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    Erase in_flist ?tW%"S^D  
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    'Tracks how many files are found w}]3jc84  
    Dim fCount As Long weTK#O0@v  
    fCount = 0 "E4i >g  
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    'Recurse directory and search for text files p
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    Dim f As String Oi+Qy[y2  
    f = Dir$(in_dir & "*.txt") c"oQ/x  
    While f <> "" 2_B;  
        ReDim Preserve in_flist(fCount) btr x?k(  
        in_flist(fCount) = f bw<~R2[  
        fCount += 1 ]JhDRJ\  
        f = Dir$() )x9nED{  
    Wend _Ct@1}aa4x  
    ReDim Preserve in_flist(fCount-1) kM6 EZ`mj  
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End Sub uL qpbn