[分享]RPC Photonics扩散片BSDF [复制链接]

摘要： &GkD5
b  
w%8y5v5  
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。 :`Ut.E~.  
AI Kz]J0;  
背景： ([}08OW@  
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。 x^1d9Z  
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。 &0tW{-Hv"  
H%gAgXHn  
n:2._s T  
{u2Zl7]z^  
步骤 g(;OUkj$Zp  
~LZrhwVj$  
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。 MkL2I+*  
dR;N3KwY  
mC$y*G  
2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） b9m`y*My  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 |w54!f6w_  
例如下所示： ~J&-~<%P}  
Sample name:  EDF-C1-56 Z"%.  
Merging data from file EDF-C1-56 0-0.txt 0c`nk\vUy  
Finished merging RPC data for sample EDF-C1-56 6/5,n0  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt 6<$.Z-,  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 0 !{X8>x  
a. 创建一个新的散射库 RL/y7M1j  
b. 散射模型命名 s1[&WDedM  
c. 改变散射模型为“Tabulated BSDF”. af %w|M  
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 ） ES AX}uF  
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。 kLF`6ZXtd  
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， M\a{2f7'n  
g. 点击OK v_Sa0
}K9  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 Fa[^D~$l*  
h7^&:  
 1n +Uv*  
脚本代码： FHw%ynC  
\X _}\_c,d  
'#Language "WWB-COM" \)rMC]  
-grmmE]/  
Option Explicit pu]U_Ll@
 
/51$o\4S  
Sub Main kN Ll|in@  
R[j?\#  
    'Cleanup l<GN<[/.+  
    ClearOutputWindow() 5WJ ~%"O  
_.Hj:nFHz  
    Print "Merging RPC Photonics BSDF Data Files" Ux*xz|^  
    SetTextColor(255,0,0) )9_W"'V  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." gBv!E9~l  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." N%}J:w  
    SetTextColor(0,0,0) F |BY]{  
+]A,fmI.  
    'Current directory of this script (should be the same as the text files being merged) \}v@!PQl  
    Dim cDir As String o>C,Db~L/  
    cDir = MacroDir$ & "\" RQ=$, i`  
kY\faWuR  
    'Array which will be populated with the list of files to be merged 2Ax"X12{6  
    Dim fList() As String, curFile As String   8sG?|u  
    GetFileList( cDir, fList ) ?Y3i-jY
  
$q:l \  
    Print "" hmo4H3g!N  
    Print "Files found for merging:" L?+N:G  
    For Each curFile In fList rHB>jN@$  
        Print Chr(9) & curFile |ugdl|f  
    Next * @]wT'  
C/Tk`C&  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. (m:Q'4E
p  
    Dim nameArray() As String, sampName As String 1>rQ).eT  
    nameArray = Split(fList(0)," 0-0.txt") #$xtUCqX  
    sampName  = nameArray(0) @9| jY1  
    Print "" ~*/ >8R(Y  
    Print "Sample name: " & Chr(9) & sampName b4cTn 6  
X
Xum2eA  
    'Open an output file and write the FRED header data @3KSoA"^  
    Dim outFile As String J Fn
E
{  
    outFile = cDir & sampName & "_FRED.txt" s 0Uid&qE  
    Open outFile For Output As #1 9)v]jk  
    Print #1, "type bsdf_data" lf>d{zd5  
    Print #1, "format angles=deg bsdf=value scale=1" s(3u\#P  
:JG5)H}j+  
    'Loop the file list, skip the two header lines and write the remaining data to file \O"H#gt  
    Dim lineArray() As String, curLine As Long 9;v3 (U+:  
    For Each curFile In fList #X'-/q`.  
        Print "Merging data from file " & curFile [-VH%OM  
        ReadFile( cDir & curFile, lineArray ) hGY-d}npAJ  
        For curLine = 2 To UBound(lineArray) }.)R#hG?  
            Print #1, lineArray(curLine) M?sax+'  
        Next x)dLY.'|  
    Next 01-rBto$  
_lkVT']  
    'Close the output file .:}<4;Qz94  
    Close #1 HJN GO[*g  
/kG?I_z  
    Print "Finished merging RPC data for sample " & sampName iXo;e  
    Print "FRED formatted data file: " & Chr(9) & outFile pP":,8Q{  
End Sub i /[{xRXiR  
i*N2@Z[  
'Utility function to read the contents of a file into an array of strings. 'uL$j
=vB  
Function ReadFile(ByVal fileName As String, _ @
NA+Ma{N  
                  ByRef lineArray() As String) As Long |e@1@q(a[]  
,dQ*0XO!  
    ReadFile = -1 }C_g;7*  
    Dim oFSO As Object E*5aLT5!,  
    Set oFSO = CreateObject("Scripting.FileSystemObject") 8Pa*d/5Y(  
    Erase lineArray ^2$b8]q  
A"M;kzAfHM  
    Dim fid As Long U.SC,;N^  
    If oFSO.fileexists( fileName ) Then rBmW%Gv  
        fid = FreeFile() k8}fKVU;  
        Open fileName For Input As fid 4z5qXI/<m4  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) 9D\E0YG X/  
        Close fid j:1N&7<FU  
    End If 6/L[`n"G  
    Set oFSO = Nothing uo]\L^j   
    Return UBound( lineArray ) ;~:Z~8+{c  
2EpQ(G J  
End Function yOl
VS@7  
) 6QJZ$  
Sub GetFileList( ByVal in_dir As String, _ $!9U\Au>2  
                 ByRef in_flist() As String ) H4 O"^#5  
2*w`l|Sx  
    'Redimension the file list array 
}GURq#  
    Erase in_flist nw/g[/<;  
hk5!
$#^  
    'Tracks how many files are found jG`PyIgw  
    Dim fCount As Long .jP|b~  
    fCount = 0 |khFQ(  
81|[Y'f  
    'Recurse directory and search for text files ]Whv%  
    Dim f As String G2wSd'n*y  
    f = Dir$(in_dir & "*.txt") C<a&]dN/  
    While f <> "" H?r~% bh  
        ReDim Preserve in_flist(fCount) Pl'lmUR  
        in_flist(fCount) = f 'j'6x'[>]  
        fCount += 1 ,ov$`v  
        f = Dir$() bz nMD  
    Wend {f4jE#a
>v  
    ReDim Preserve in_flist(fCount-1) P|ibUxSA~,  
sqhIKw@  
End Sub a+v.(mCG  
)UU`uzU;u  
aOinD  
QQ：2987619807 #s\yO~F-