[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？ }_Sg
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一下是我的Prescription Data数据： \jkDRR[  
GENERAL LENS DATA: 2V+[:>F  
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Surfaces                :                3 SnO,-Rg  
Stop                    :                1 ZhoB/TgdL  
System Aperture         : Object Space NA = 0.12 1&kf2\S  
Glass Catalogs          : Schott Gn10)Uf8X  
Ray Aiming              : Paraxial Reference, Cache On FW<YN;  
X Pupil shift          :               0 2b#>
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Y Pupil shift          :               0 %=v<3  
Z Pupil shift          :               0 (%M:=zm  
Apodization             : Gaussian, factor =   1.00000E+000 gp{P _  
************************************************************* R ta_\Aj!  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) #M[Cq= 2  
Effective Focal Length  :        1.639158 (in image space) $:DhK  
************************************************************* } /Iw]!lK2  
Back Focal Length       :       -1.061568 uC`)?f*I  
Total Track             :           4.318 G&0JK ,Y  
Image Space F/#         :        3.417255 hA"z0Fszh  
Paraxial Working F/#    :        2.950535 KR4RIJZ_t  
Working F/#             :        2.961912 gD6BPW~0  
Image Space NA          :       0.1670788 G{|FV m  
Object Space NA         :            0.12 'BEM:1)  
Stop Radius             :       0.2398355 A)^A2xZQ  
Paraxial Image Height   :               0 !un_JZD  
Paraxial Magnification  :               0 gJZ9XLPC  
Entrance Pupil Diameter :       0.4796709 LGVGr  
Entrance Pupil Position :               0 @/?$ZX/e[  
Exit Pupil Diameter     :        2.511155 S#7.
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Exit Pupil Position     :        7.420935 `qbsDfq@  
Field Type              : Angle in degrees r\{; ~V  
Maximum Field           :               0 AyZBH&}RZ  
Primary Wave            :            1.31 ch}(v'xv(  
Lens Units              :   Millimeters nr{}yQu  
Angular Magnification   :               0 "{(4  
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Fields          : 1 noNL.%I  
Field Type: Angle in degrees .gHL(*1P  
#        X-Value        Y-Value         Weight qUp DmH  
1       0.000000       0.000000       1.000000 `L}Irt}  
-U_<:  
Vignetting Factors })r[qsv  
#       VDX       VDY       VCX       VCY       VAN \LW '6 pQ_  
1  0.000000  0.000000  0.000000  0.000000  0.000000 30/(  
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Wavelengths     : 1 kv3jbSK
CT  
Units: Microns v~>4c<eG  
#          Value         Weight r`/tb
^  
1       1.310000       1.000000 "Mmvf'N  
rru `%~'O  
CARDINAL POINTS: I"+;L4o`  
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Object space positions are measured with respect to surface 1. =Wk!mGc  
Image space positions are measured with respect to the image surface. 2myHn/%C  
The index in both the object space and image space is considered. enJE#4Z5&s  
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                          Object Space         Image Space )zVD!eG_9  
W = 1.310000 (Primary) ojd/%@+u+Y  
************************************************************ #S4{,  
Focal Length          :           -1.639015            1.639015 w_i$/`i+  
************************************************************ %.D@{O  
Focal Planes          :            0.313078           -1.159568 .Su9fjy%  
Principal Planes      :            1.952094           -2.798584 8aD4wc  
Anti-Principal Planes :           -1.325937            0.479447 sL tsvH#  
Nodal Planes          :            1.952094           -2.798584 t1 .6+  
Anti-Nodal Planes     :           -1.325937            0.479447 m/0t; cx  
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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