[分享]RPC Photonics扩散片BSDF [复制链接]

摘要： {=+'3p  
(?P\;yDG  
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。 cq$_$jRx  
d;).| .}P  
背景： |gfG\fL3V  
Thorlabs和RPC Photonics联手共同推出的新型漫射体及光束整形技术，可以解决其他技术的不足，大大改善了诸如光刻系统、有效固态照明，显示，背光，显示亮度增强和投影屏等大多数应用的性能。这项我们称之为工程漫射体（Engineered DiffusersTM）的新概念，与其他技术有许多不同。与诸如磨砂玻璃、乳色玻璃和全息元件等随机漫射体截然不同，工程漫射体要求对于每个散射中心，通常为微透镜单元，都进行控制。例如全息漫射体可以视为一组随机排列的透镜，但是通过全息曝光形成的类透镜效果只能通过静态方式进行控制：而无法单独操控每个微透镜单元，这也帮助解释了全息漫射体无法控制光的分布和轮廓。另一方面，在工程漫射体中，每个微透镜单元形成漫射体，由其凹形纵断面和在阵列中的位置所确定。同时，为了确保漫射体不受输入光束变化的影响，并且不产生衍射效果，微透镜单元的分布是随机的，根据产生相应的光束形状函数所选取的概率分布函数来确定。因此，工程漫射体同时保留了随机与确定性漫射体的优点，从而实现高性能的光束整形功能。 Q776cj^L  
FRED是美国Photon Engineering 公司开发的光学工程仿真软件，其在杂散光分析中独特的算法、高效的准确性，使其与其它同类产品相比更具优势。本案例我们重点讲述如何由RPC Photonics的BSDF数据转为FRED可识别的散射数据。 g,f AVM  
eX'V#K#C  
U<"k-  
L(HAAqRn
J  
步骤 pwNF\ ={  
2UTmQOm  
1、 在http://www.rpcphotonics.com/bsdf-data-optical-diffusers/下载并解压BSDF数据到某一文件夹下，选择“Raw data”文件。 O 2+taB  
nMBF/75  
7<LCX{Uw  
2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） w%%*3[--X  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 uFfk!  
例如下所示： id>2G %Tx  
Sample name:  EDF-C1-56 0fN; L;v  
Merging data from file EDF-C1-56 0-0.txt @ b}-<~  
Finished merging RPC data for sample EDF-C1-56 "?'9\<>  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt 7_L$XIa  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 -E.fo._L5  
a. 创建一个新的散射库 ye4GHAm,p  
b. 散射模型命名 _DYe<f.  
c. 改变散射模型为“Tabulated BSDF”. nlc$"(eA[H  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） e8k|%m<Sp  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 xr31<
4B  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线，
F1%^,;  
g. 点击OK pzT`.#N:M  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 L^Fb;sJYI  
k:z)Sw  
}RUK?:lEA  
脚本代码： r(g#3i4Q  
9x#Tj/5%  
'#Language "WWB-COM" )~ ^`[`  
Axla@  
Option Explicit 9dva]$^:*1  
<jh=W9.N_  
Sub Main /wi/i*;A  
$?DEO[p.  
    'Cleanup NOl/y@#  
    ClearOutputWindow() D=M'g}l  
D_BdvWSxj  
    Print "Merging RPC Photonics BSDF Data Files" r%`3*<ALV)  
    SetTextColor(255,0,0) 
R?#.z#  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." +)_#j/  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." l=<},_]{  
    SetTextColor(0,0,0) -+:t%A?  
H?;@r1ZAn  
    'Current directory of this script (should be the same as the text files being merged) 8`Tj*7Y=  
    Dim cDir As String _D8:p>=  
    cDir = MacroDir$ & "\" O]t)`+%q  
N,&bBp  
    'Array which will be populated with the list of files to be merged 'T]Ok\  
    Dim fList() As String, curFile As String ">q?(i\  
    GetFileList( cDir, fList ) UryHte  
lN*"?%<
x>  
    Print "" "J2v8c  
    Print "Files found for merging:" )!'7!" $  
    For Each curFile In fList ov1#BeQ  
        Print Chr(9) & curFile BuOe'$F 0t  
    Next 1+xi1w}3a  
,E2c9V'  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. n]3Z~HoZ  
    Dim nameArray() As String, sampName As String -~ Dn^B1^  
    nameArray = Split(fList(0)," 0-0.txt") |A2o$H  
    sampName  = nameArray(0) {&nDm$KTD  
    Print "" ESuP ZB  
    Print "Sample name: " & Chr(9) & sampName C-/+n5J  
CUj$ <ay=  
    'Open an output file and write the FRED header data A9z3SJ\vXl  
    Dim outFile As String gj82qy\:  
    outFile = cDir & sampName & "_FRED.txt" SGpe\P]k  
    Open outFile For Output As #1 }'h\;8y  
    Print #1, "type bsdf_data" Q>TNzh  
    Print #1, "format angles=deg bsdf=value scale=1" UK.=Y9  
4\ny]A:~  
    'Loop the file list, skip the two header lines and write the remaining data to file 6dYa07  
    Dim lineArray() As String, curLine As Long BipD8`a  
    For Each curFile In fList 9!6u Yf+  
        Print "Merging data from file " & curFile DN;$->>  
        ReadFile( cDir & curFile, lineArray ) &0OH:P%  
        For curLine = 2 To UBound(lineArray) q'%!qa+  
            Print #1, lineArray(curLine) U:8cz=#  
        Next m[Qr>="  
    Next hPt=j{aJ%<  
DO~~  
    'Close the output file 7Kti&T  
    Close #1 LftzW{>gI"  
}{.V^;  
    Print "Finished merging RPC data for sample " & sampName 2]H?q!l!O  
    Print "FRED formatted data file: " & Chr(9) & outFile H`7T;`Yb  
End Sub J$&2GAi  
^%qQ)>I=j  
'Utility function to read the contents of a file into an array of strings. 3Q_)Xs r`  
Function ReadFile(ByVal fileName As String, _ /.(F\2+A  
                  ByRef lineArray() As String) As Long *7),v+ET  
h2 >a_0"  
    ReadFile = -1 [V0%=q+R  
    Dim oFSO As Object *\^(-p~M  
    Set oFSO = CreateObject("Scripting.FileSystemObject") j{HIdP  
    Erase lineArray S~GS:E#  
W&2r{kCsQ  
    Dim fid As Long I3YSW  
    If oFSO.fileexists( fileName ) Then -90X^]  
        fid = FreeFile() *?o 'sTH  
        Open fileName For Input As fid R)%I9M,  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) m21H68y  
        Close fid (>gb9n  
    End If ,+FiP{`  
    Set oFSO = Nothing y>ePCDR3  
    Return UBound( lineArray ) Nk?/vMaw  
ty8E;['  
End Function m2Wi "X(I_  
3GXmyo:o$  
Sub GetFileList( ByVal in_dir As String, _ KnUVR!H|  
                 ByRef in_flist() As String ) e)|5P  
c`7dNx  
    'Redimension the file list array {ApjOIxk  
    Erase in_flist _]us1  
'w_Qs~6~{  
    'Tracks how many files are found #X0Y8:vj  
    Dim fCount As Long OOzXA%<%c  
    fCount = 0 D~ 7W  
O?iLLfs  
    'Recurse directory and search for text files c>wne\(5H  
    Dim f As String [vxHsY3z  
    f = Dir$(in_dir & "*.txt") KuMH,rXF  
    While f <> "" \Z-Fu=8J8^  
        ReDim Preserve in_flist(fCount) 2W;2._  
        in_flist(fCount) = f "fu@2y4^  
        fCount += 1 %ejq|i7  
        f = Dir$() &,$N|$yK}|  
    Wend _[N*k"  
    ReDim Preserve in_flist(fCount-1) ZN!<!"~  
!'a <Dw5  
End Sub ym2"D?P (  
0Q[;{}W}  
]qiX"<s>~C  
QQ：2987619807 i~rb-~o