[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？ Fi mN?s  
一下是我的Prescription Data数据： "(s6aqO$  
GENERAL LENS DATA: t#C,VwMe[  
n[!
;yO  
Surfaces                :                3 AY#wVy  
Stop                    :                1 >(X#<`  
System Aperture         : Object Space NA = 0.12 I*EJHBsQ5  
Glass Catalogs          : Schott "\e:h| .G  
Ray Aiming              : Paraxial Reference, Cache On 4-mVB wq  
X Pupil shift          :               0 \gLxC  
Y Pupil shift          :               0 g>so R&*  
Z Pupil shift          :               0 *HR+a#o  
Apodization             : Gaussian, factor =   1.00000E+000 l , ..5   
************************************************************* {fZb@7?GF  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) v=!YfAn  
Effective Focal Length  :        1.639158 (in image space) P0^c?s"I  
************************************************************* ?hnx/z+uT  
Back Focal Length       :       -1.061568 eP"`,<  
Total Track             :           4.318 "'m)VG  
Image Space F/#         :        3.417255 \[yr=X  
Paraxial Working F/#    :        2.950535 |^R*4;Phe  
Working F/#             :        2.961912 \K;op2  
Image Space NA          :       0.1670788 8".2)W4*  
Object Space NA         :            0.12 cJCU*(7&  
Stop Radius             :       0.2398355 B`
fH^N  
Paraxial Image Height   :               0 o\Uu?.-<  
Paraxial Magnification  :               0 jpRBER_X  
Entrance Pupil Diameter :       0.4796709 W{ fZ[z  
Entrance Pupil Position :               0 F/>*Ifs  
Exit Pupil Diameter     :        2.511155 lwc5S`"  
Exit Pupil Position     :        7.420935 J!{Al  
Field Type              : Angle in degrees ow$q7uf  
Maximum Field           :               0 \R(R9cry  
Primary Wave            :            1.31 *m9{V8Yi2  
Lens Units              :   Millimeters En(7(qP6}  
Angular Magnification   :               0 g+xw$A ou  
.wmnnvtl,  
Fields          : 1 K/txD20 O|  
Field Type: Angle in degrees [$pmPr2  
#        X-Value        Y-Value         Weight ciudRK63M  
1       0.000000       0.000000       1.000000 4:7mK/Z  
gY(1,+0-  
Vignetting Factors R_^/,^1  
#       VDX       VDY       VCX       VCY       VAN {CtR+4KD  
1  0.000000  0.000000  0.000000  0.000000  0.000000  4*TmlY  
i
ib  
Wavelengths     : 1 (luKn&826  
Units: Microns zvY+R\,in  
#          Value         Weight  W^Y#pn  
1       1.310000       1.000000 "X04mQn15  
WNs}sNSf  
CARDINAL POINTS: y7:tr  
D'b#,a;V  
Object space positions are measured with respect to surface 1. $d/&k`  
Image space positions are measured with respect to the image surface. -Fxm
si  
The index in both the object space and image space is considered. Dzl;-]S  
~>Kq<]3~  
                          Object Space         Image Space =wG+Ao  
W = 1.310000 (Primary) 7AwgJb hn  
************************************************************ paW@\1Q  
Focal Length          :           -1.639015            1.639015 /*$hx@ih  
************************************************************ oFDz;6  
Focal Planes          :            0.313078           -1.159568 kkS~4?-*  
Principal Planes      :            1.952094           -2.798584 y<- _(^  
Anti-Principal Planes :           -1.325937            0.479447 yHeEobvb  
Nodal Planes          :            1.952094           -2.798584 C3XmK}h  
Anti-Nodal Planes     :           -1.325937            0.479447 /6KIl  
Pf<[|yu4?  
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