[求助]关于Effective focal length的问题 [复制链接]

  ZEMAX中priscription data会给出系统的许多有用的数据，其中包括effective focal length的数据和主平面位置的数据。但是我发现直接给出的effective focal length数据和根据其定义结合主平面的数据算出来的结果不一致，这时怎么回事？ 2_q/
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一下是我的Prescription Data数据： qYK^S4L  
GENERAL LENS DATA: g-eJan&]N  
(/A.,8Ad  
Surfaces                :                3 MTu\T  
Stop                    :                1 TTXF r  
System Aperture         : Object Space NA = 0.12 "wgPPop  
Glass Catalogs          : Schott OG5{oH#K  
Ray Aiming              : Paraxial Reference, Cache On zjmoIE  
X Pupil shift          :               0 \u,CixV=  
Y Pupil shift          :               0 #_DpiiS,.Q  
Z Pupil shift          :               0 Fi i(dmn  
Apodization             : Gaussian, factor =   1.00000E+000 Uu_qy(4  
************************************************************* p*Z<DEh#  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) `NIb?/!f  
Effective Focal Length  :        1.639158 (in image space) Z
)7{~xq  
************************************************************* &W45.2  
Back Focal Length       :       -1.061568 WZ'<iI  
Total Track             :           4.318 T8S&9BM7  
Image Space F/#         :        3.417255 }>{R<[I!G  
Paraxial Working F/#    :        2.950535 ),x0G*oebj  
Working F/#             :        2.961912 zDvV%+RW)  
Image Space NA          :       0.1670788 rS [4Pey  
Object Space NA         :            0.12 dcf,a<K\  
Stop Radius             :       0.2398355 k-~}KlP  
Paraxial Image Height   :               0 &]TniQH  
Paraxial Magnification  :               0 b7sfr!t_d  
Entrance Pupil Diameter :       0.4796709 WsHDIp  
Entrance Pupil Position :               0 d:'{h"M6  
Exit Pupil Diameter     :        2.511155 Ichg,d-M-K  
Exit Pupil Position     :        7.420935 5gf ~/Zr  
Field Type              : Angle in degrees y4kn2Mw;  
Maximum Field           :               0 #(tdJ<HvC|  
Primary Wave            :            1.31 R>b
g3j  
Lens Units              :   Millimeters k6#$Nb606  
Angular Magnification   :               0 EID-ROMO  
y3efie {J  
Fields          : 1 lV'?X%  
Field Type: Angle in degrees EB3/o7)L  
#        X-Value        Y-Value         Weight #6M |T+=  
1       0.000000       0.000000       1.000000 :Ra
cu;xf  
z};|.N}  
Vignetting Factors _WS8I>  
#       VDX       VDY       VCX       VCY       VAN ew\:&"@2]w  
1  0.000000  0.000000  0.000000  0.000000  0.000000 y3;M$Jr  
Uh.swBC n  
Wavelengths     : 1 |sGJum&=  
Units: Microns .i;.5)shsu  
#          Value         Weight fq>{5ODO  
1       1.310000       1.000000 aj4ZS  
:}NheRi  
CARDINAL POINTS: B2NIV
7  
AJ\gDjj<  
Object space positions are measured with respect to surface 1. dQ*^WNUB  
Image space positions are measured with respect to the image surface. ?b7ttlX{  
The index in both the object space and image space is considered. ;L$-_Z  
FRxR/3&  
                          Object Space         Image Space !>F70  
W = 1.310000 (Primary) +&\. ]Pp  
************************************************************ b}(c'W*z%  
Focal Length          :           -1.639015            1.639015 ICz:>4M-dn  
************************************************************ "EpH02{i  
Focal Planes          :            0.313078           -1.159568 ZY<RNwu  
Principal Planes      :            1.952094           -2.798584 (&.T  
Anti-Principal Planes :           -1.325937            0.479447 ;8<HB1 &,  
Nodal Planes          :            1.952094           -2.798584 @tSB^&jUWu  
Anti-Nodal Planes     :           -1.325937            0.479447 .-YE(}^  
GG%;~4#2  
我用*号，标出了需要注意的地方，请高手指教！

各位指点一下吧，自己顶起来！

帮顶！！！！！！！！！！！！！！1

等待高手帮忙吧 我也不会!

看的我头晕了,可能是感冒的缘故吧,以后有机会再探讨

我也不会先看看再说!~

慢慢理解