[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？ l]G iz&  
一下是我的Prescription Data数据： =A!oLe$%  
GENERAL LENS DATA: sOqFEvzo1%  
6B]=\H  
Surfaces                :                3 P!-RZEt$  
Stop                    :                1 >5O~S
F.  
System Aperture         : Object Space NA = 0.12 R;HE{q[ f  
Glass Catalogs          : Schott *iB&tWv  
Ray Aiming              : Paraxial Reference, Cache On ,^bgk -x-  
X Pupil shift          :               0 5mamWPw  
Y Pupil shift          :               0 Cab-:2L]  
Z Pupil shift          :               0 'p5M|h\:T  
Apodization             : Gaussian, factor =   1.00000E+000 GZO:lDdA  
************************************************************* WIU]>_$.  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) pW+uVv,  
Effective Focal Length  :        1.639158 (in image space) ;_\yg)X,  
************************************************************* h: yJ  
Back Focal Length       :       -1.061568 D%+yp  
Total Track             :           4.318 !aSj1 2J  
Image Space F/#         :        3.417255 /KvJjt'8  
Paraxial Working F/#    :        2.950535 .I_atv  
Working F/#             :        2.961912 ezw*Lo!  
Image Space NA          :       0.1670788 =rymd3/  
Object Space NA         :            0.12 x8aOXN#w}  
Stop Radius             :       0.2398355 ?OW!D?  
Paraxial Image Height   :               0 ]Ea-MeH  
Paraxial Magnification  :               0 CUJq [  
Entrance Pupil Diameter :       0.4796709 XQ~Xls%]   
Entrance Pupil Position :               0 Q z(n41@`  
Exit Pupil Diameter     :        2.511155 N.mRay,  
Exit Pupil Position     :        7.420935 uxyj6(  
Field Type              : Angle in degrees j-d&4,a:c  
Maximum Field           :               0
e?XFtIj$  
Primary Wave            :            1.31 e6MBy\*n  
Lens Units              :   Millimeters .Wt3|?\=nd  
Angular Magnification   :               0 U[MeK)*  
%|JiFDjp  
Fields          : 1 ='jT 5Mg  
Field Type: Angle in degrees &]YyV.
 
#        X-Value        Y-Value         Weight 7j)ky2r#  
1       0.000000       0.000000       1.000000 JPn)Op6  
U;/2\Ii  
Vignetting Factors 3Ewdu
 
#       VDX       VDY       VCX       VCY       VAN F.U@8lr  
1  0.000000  0.000000  0.000000  0.000000  0.000000 |Uics:cQC  
.K84"Gdx  
Wavelengths     : 1 T1qbb*  
Units: Microns s! 2[zJ19p  
#          Value         Weight EMP|I^  
1       1.310000       1.000000 g"748LY>=p  
|!] "y<  
CARDINAL POINTS: 6yy%_+k*  
:pM8Q1:B  
Object space positions are measured with respect to surface 1. ^vMlRt;  
Image space positions are measured with respect to the image surface. /?r A|  
The index in both the object space and image space is considered. HL&HY)W1gf  
^2}HF/  
                          Object Space         Image Space !-tw  
W = 1.310000 (Primary) t$du|q(  
************************************************************ Uj;JN}k  
Focal Length          :           -1.639015            1.639015 O
)`L( x  
************************************************************ Xk.OyQ@  
Focal Planes          :            0.313078           -1.159568 ;@=3 @v  
Principal Planes      :            1.952094           -2.798584 h,FU5iK|  
Anti-Principal Planes :           -1.325937            0.479447 zc8^#D2y&  
Nodal Planes          :            1.952094           -2.798584 el`?:dY H  
Anti-Nodal Planes     :           -1.325937            0.479447 3F]Dh^IR9  
^+Nd\tp  
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