[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： K1_#Jhz  
S
sfH
p  
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。 \@F~4,VT  
i{2ny$55h  
背景： w6<zPrA  
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。 kpLx?zW--q  
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。 u.9syr  
Qf.]Mw?Bm  
+V;@)-   
Su*f`~G];  
步骤 fA" VLQE  
(y!V0iy]  
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。 z( ^ r  
_,bDv`>Ra  
ukwO%JAr  
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） h;JO"J@H  
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 zn2Qp  
例如下所示： %Gc)
$z/Wd  
Sample name:  EDF-C1-56 :@]%n~x  
Merging data from file EDF-C1-56 0-0.txt i&Xjbcbp  
Finished merging RPC data for sample EDF-C1-56 @D+2dT0[M  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt 'wd&O03&  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 LyNLz m5  
a. 创建一个新的散射库 ?*dt JL  
b. 散射模型命名 )m<CmYr2  
c. 改变散射模型为“Tabulated BSDF”. xjH({(/B>a  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） :O/QgGZN$  
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。 H}PZJf_E  
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， T))F r:  
g. 点击OK qj:\)#I  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 {jOV8SVL  
B*&HQW *u  
..;ep2jSs  
脚本代码： $9rQ w1#e  
~jDf,a2  
'#Language "WWB-COM" _0h)O  
aU?HIIA  
Option Explicit cllnYvr3  
Y0xn}:%K  
Sub Main  ?~=5x  
{vox x&UX  
    'Cleanup ?4H>1Wk
b  
    ClearOutputWindow() "a=dx| Z  
LtVIvZie  
    Print "Merging RPC Photonics BSDF Data Files" 3F?_{A  
    SetTextColor(255,0,0) |"i"8~/@<  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." xM2UwTpW  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." QQ\\:]iM  
    SetTextColor(0,0,0) /4{IxQk  
9?zi  
    'Current directory of this script (should be the same as the text files being merged) &h'NC%
"v  
    Dim cDir As String Tu&W7aoX5  
    cDir = MacroDir$ & "\" 0P^&{ek+)  
Y[.f`Ei2  
    'Array which will be populated with the list of files to be merged bmI6OIWl  
    Dim fList() As String, curFile As String > K s.  
    GetFileList( cDir, fList ) pz ~REsx  
MoC@n+Q+@  
    Print "" {4YD_$4W  
    Print "Files found for merging:" L17{W4  
    For Each curFile In fList 80"oT'ZFh  
        Print Chr(9) & curFile P0ZY;/e5h  
    Next 1BOv|xPjZ  
8Az|SJ<  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. ]6@6g>f?  
    Dim nameArray() As String, sampName As String {ug*  
    nameArray = Split(fList(0)," 0-0.txt") @Zw[LIQ*  
    sampName  = nameArray(0) X]c>clk,  
    Print "" ()(^B}VK  
    Print "Sample name: " & Chr(9) & sampName v(~EO(n.  
Z
DbzH=[  
    'Open an output file and write the FRED header data w-P;E!gTt  
    Dim outFile As String XVzsqi*Z  
    outFile = cDir & sampName & "_FRED.txt" LX{mr{  
    Open outFile For Output As #1 `i)Pf WdBN  
    Print #1, "type bsdf_data" y1#*c$ O  
    Print #1, "format angles=deg bsdf=value scale=1" dfWtLY  
m;
{(U Z  
    'Loop the file list, skip the two header lines and write the remaining data to file =k##*%  
    Dim lineArray() As String, curLine As Long k%?qN,Cl  
    For Each curFile In fList 3v>w$6  
        Print "Merging data from file " & curFile k|3hs('y|  
        ReadFile( cDir & curFile, lineArray ) %hi]oz  
        For curLine = 2 To UBound(lineArray) V>& 1;n  
            Print #1, lineArray(curLine) Kj/Lcx;bh  
        Next y/;DA=  
    Next  V0!kvIv  
oQK,#>rv  
    'Close the output file p Cgm!t?/  
    Close #1 'RZ0,SK'  
He1~27+99  
    Print "Finished merging RPC data for sample " & sampName =4 NKXP~C  
    Print "FRED formatted data file: " & Chr(9) & outFile
zuI7Px  
End Sub =}'7}0M_=  
T$1(6<:+.  
'Utility function to read the contents of a file into an array of strings. N9 TM  
Function ReadFile(ByVal fileName As String, _ gdkHaLL"  
                  ByRef lineArray() As String) As Long wQ?Z y;/S  

SXx4^X  
    ReadFile = -1 k_`YVsEYP  
    Dim oFSO As Object ~toR)=Yv  
    Set oFSO = CreateObject("Scripting.FileSystemObject") : `,#z?Rk  
    Erase lineArray \0.!al0  
wowWq\euY  
    Dim fid As Long &neB$m3y  
    If oFSO.fileexists( fileName ) Then \?[m%$A  
        fid = FreeFile() ~(]'ah,  
        Open fileName For Input As fid 8@r>`c  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) *0Wkz
'=U  
        Close fid $ZlzS`XF7  
    End If 6W9lKD_i  
    Set oFSO = Nothing sNZOm$  
    Return UBound( lineArray ) 5MK.>3fE  
?MOjtAG0_~  
End Function O)c3Lm-w  
p~OX1RBI  
Sub GetFileList( ByVal in_dir As String, _ >N"=10  
                 ByRef in_flist() As String ) 7>f)pfLM  
F]cc?r312  
    'Redimension the file list array kH?PEA! \  
    Erase in_flist HG^
~7oMf  
wlpcuz@  
    'Tracks how many files are found .J?RaH{i  
    Dim fCount As Long lL&p?MUp  
    fCount = 0 Y4N)yMSl"  
]F #0
to  
    'Recurse directory and search for text files \6!s";=hQ  
    Dim f As String AmK g;9LS  
    f = Dir$(in_dir & "*.txt") Sg1,9[pb  
    While f <> "" f!G%$?]  
        ReDim Preserve in_flist(fCount) d>wG6Z,|  
        in_flist(fCount) = f Yu:($//w  
        fCount += 1 S+l>@wa)|  
        f = Dir$() xP &@|Ag  
    Wend at(gem   
    ReDim Preserve in_flist(fCount-1) J
]|S0JC`  
kfq<M7y  
End Sub [ZD`t,x(