[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？  jH>`:  
一下是我的Prescription Data数据： yXT8:2M  
GENERAL LENS DATA: 3>QkO.b  
???`BF[|  
Surfaces                :                3 (NC]S  
Stop                    :                1 Lz{z~xNHW.  
System Aperture         : Object Space NA = 0.12 AX;!-|bW  
Glass Catalogs          : Schott xtO#reL"q?  
Ray Aiming              : Paraxial Reference, Cache On Fj4>)!^kM  
X Pupil shift          :               0 ohna1a^  
Y Pupil shift          :               0 B;e (5y-  
Z Pupil shift          :               0 5yk#(i7C  
Apodization             : Gaussian, factor =   1.00000E+000 AF\Jh+ynT!  
************************************************************* z"P/Geb:O  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) QTC!vKM  
Effective Focal Length  :        1.639158 (in image space) fLS].b]1N  
************************************************************* #f<3[BLx  
Back Focal Length       :       -1.061568 ( 4(,"  
Total Track             :           4.318 5Ky(C6E$s  
Image Space F/#         :        3.417255 .F},Z[a&  
Paraxial Working F/#    :        2.950535 qWM+!f  
Working F/#             :        2.961912 LyH1tF  
Image Space NA          :       0.1670788 @ Fkhida  
Object Space NA         :            0.12 pZz\o  
Stop Radius             :       0.2398355 4-m6e$p;  
Paraxial Image Height   :               0 7@ \:l~{  
Paraxial Magnification  :               0 >#VNA^+t  
Entrance Pupil Diameter :       0.4796709 1xI  
Entrance Pupil Position :               0 y9b%P]i  
Exit Pupil Diameter     :        2.511155 ]f_`w81[  
Exit Pupil Position     :        7.420935 %Ai' 6  
Field Type              : Angle in degrees _iL?kf  
Maximum Field           :               0 ?4^ 0xGyE  
Primary Wave            :            1.31 \PWH(E9  
Lens Units              :   Millimeters &~=r .T  
Angular Magnification   :               0 1mD)G55Ep  
'o~gT ;T#  
Fields          : 1 LcZ|A;it  
Field Type: Angle in degrees M|NQoQ8q  
#        X-Value        Y-Value         Weight 1yVhO2`7]  
1       0.000000       0.000000       1.000000 2VzYP~Jg  
5|5p -B  
Vignetting Factors IC?(F]$%>  
#       VDX       VDY       VCX       VCY       VAN Yt?]0i+  
1  0.000000  0.000000  0.000000  0.000000  0.000000 "9 f
+F  
*YSRZvD<\  
Wavelengths     : 1 bQ(-M:  
Units: Microns 3)yL#hXg)  
#          Value         Weight `/^ _W <  
1       1.310000       1.000000 .cbC2t95  
0<O()NMv  
CARDINAL POINTS: n*
Uk<_WA  
h aApw(.%  
Object space positions are measured with respect to surface 1. A,BYi$  
Image space positions are measured with respect to the image surface. K`2(Q  
The index in both the object space and image space is considered. FWA?mde  
Vd(n2JMtG  
                          Object Space         Image Space tj$[szo  
W = 1.310000 (Primary) @$~IPg[J  
************************************************************ ?w+ V:
D  
Focal Length          :           -1.639015            1.639015 Q;J( 5;  
************************************************************ M~N/er  
Focal Planes          :            0.313078           -1.159568 5'c#pm\Q  
Principal Planes      :            1.952094           -2.798584 2;u i'B  
Anti-Principal Planes :           -1.325937            0.479447 $dF3@(p  
Nodal Planes          :            1.952094           -2.798584 :eSsqt9]9  
Anti-Nodal Planes     :           -1.325937            0.479447 2j}DI"|h  
R3;%eyu  
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