[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： 7JHS8C<]  
Du."O]syD  
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。 [.`%]Z(  
s/J/kKj*s  
背景： a#o6Nv  
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。 y:3d`E4Xw  
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。 v9R"dc]0h  
Y94/tjt  
!@vM@Z"  
nfbqJ  
步骤 @"E{gM@B  
xMAb=87_  
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。 u t4+c0  
'fkaeFzOl  
1-bQ ( -  
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） Z2x%  
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  {!9i8T  
例如下所示： x3++JG  
Sample name:  EDF-C1-56 c@1q8,  
Merging data from file EDF-C1-56 0-0.txt #RA3 T[A  
Finished merging RPC data for sample EDF-C1-56 /P3s.-sL  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt [M{EO)  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 ?dcR!-3  
a. 创建一个新的散射库 `bF]
O"  
b. 散射模型命名 >&3ATH;&(  
c. 改变散射模型为“Tabulated BSDF”. k;9"L90  
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 ） s"solPw  
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。 )"o+wSI1  
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， >)IXc<"wq  
g. 点击OK f YuM`O  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 :9Vd=M6,  
Y[yw8a  
@~l?hf  
脚本代码： "<J%@  
hIr$^%  
'#Language "WWB-COM" Y/1,%8n  
M"t=0[0DM:  
Option Explicit )5Bkm{v3  
_\tGmME37  
Sub Main <.h\%&'U  
u70-HFI@  
    'Cleanup <XH

S@|  
    ClearOutputWindow() X}5a
E4K/  
(cj3[qq  
    Print "Merging RPC Photonics BSDF Data Files" aumXidbS  
    SetTextColor(255,0,0) 7Z;w<b~  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." XFg.Z+ #  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." dWI.t1`i  
    SetTextColor(0,0,0) r_kw "9  
&z\]A,=Tc  
    'Current directory of this script (should be the same as the text files being merged) BI\+NGrB  
    Dim cDir As String ^3-Wxn9&  
    cDir = MacroDir$ & "\" PZdYkbj  
N+vU@)_lC  
    'Array which will be populated with the list of files to be merged 7Pc0|Z/  
    Dim fList() As String, curFile As String ClHaR  
    GetFileList( cDir, fList ) g1uqsqYt  
WR*|k
h  
    Print "" a#0GmK  
    Print "Files found for merging:" W].P(A
>m  
    For Each curFile In fList Jb~-)n2  
        Print Chr(9) & curFile ')9%eBaeK  
    Next 4R U1tWQ%  
B=;pyhc  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. lbES9o5  
    Dim nameArray() As String, sampName As String sJlX]\RLQ  
    nameArray = Split(fList(0)," 0-0.txt") toipEp<ci  
    sampName  = nameArray(0) / -=(51}E  
    Print "" Zw5\{Z0  
    Print "Sample name: " & Chr(9) & sampName n(Up?_  
T$]2U>=<J  
    'Open an output file and write the FRED header data OU(z};Is6Z  
    Dim outFile As String 6[9E^{(z  
    outFile = cDir & sampName & "_FRED.txt"  :*M\z3`k  
    Open outFile For Output As #1 ]kmOX  
    Print #1, "type bsdf_data" /s%I(iP4  
    Print #1, "format angles=deg bsdf=value scale=1" 0;)6ZU  
/S;o2\  
    'Loop the file list, skip the two header lines and write the remaining data to file (%>Sln5hq  
    Dim lineArray() As String, curLine As Long (oxe\Qk  
    For Each curFile In fList xQ7n$.?y@  
        Print "Merging data from file " & curFile s9A'{F  
        ReadFile( cDir & curFile, lineArray ) ISr~JQr  
        For curLine = 2 To UBound(lineArray) 13
Z6dhZu  
            Print #1, lineArray(curLine) ucj)t7O   
        Next 4[3T%jA  
    Next oQDOwM,  
9ok|]d P  
    'Close the output file HHZ!mYr  
    Close #1 *eXO?6f%s^  
K74oRKv  
    Print "Finished merging RPC data for sample " & sampName ^+[o+  
    Print "FRED formatted data file: " & Chr(9) & outFile dW7dMx  
End Sub q rbF@{  
%:o@IRTRU  
'Utility function to read the contents of a file into an array of strings. T , =ga  
Function ReadFile(ByVal fileName As String, _ >B~jPU  
                  ByRef lineArray() As String) As Long >V(2Ke Y  
SEchF"KJQF  
    ReadFile = -1 ~+>M,LfK  
    Dim oFSO As Object LbR/it'}  
    Set oFSO = CreateObject("Scripting.FileSystemObject") l7{hq}@;cC  
    Erase lineArray ?<frU ,{  
z K8#gif@  
    Dim fid As Long @\l> <R9V  
    If oFSO.fileexists( fileName ) Then 5 J|;RtcR  
        fid = FreeFile() d L%
E0o  
        Open fileName For Input As fid , m|9L{  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) `^J~^Z7Y-  
        Close fid A?}OOjA  
    End If lO $M6l  
    Set oFSO = Nothing GP1>h.J  
    Return UBound( lineArray ) H[N&Wiq/|  
)Qxv9:X  
End Function Y)u}+Yg  
 ^RWt  
Sub GetFileList( ByVal in_dir As String, _ \>=YxB q  
                 ByRef in_flist() As String ) 2K*-uT#$~  
J|FyY)_  
    'Redimension the file list array cHsJQU*K6  
    Erase in_flist Z `\7B e  
'fAD Dh}  
    'Tracks how many files are found jZ 
D\u%  
    Dim fCount As Long vWkKNB  
    fCount = 0 T4!]^_t^  
x>8f#B\Mr  
    'Recurse directory and search for text files <$yer)_J!k  
    Dim f As String H9)uni   
    f = Dir$(in_dir & "*.txt") _Mt:^H}Sy  
    While f <> "" UiZ61lw  
        ReDim Preserve in_flist(fCount) _&%!4n#>  
        in_flist(fCount) = f J#x91Jh  
        fCount += 1 .sG,TLE[<  
        f = Dir$() C]=E$^|{  
    Wend Ba+OoS  
    ReDim Preserve in_flist(fCount-1) >Au<y,Tw  
5ZKnxEW,(  
End Sub
ABHZ)OM