[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？ !P"?  
一下是我的Prescription Data数据： h3h8lt_|  
GENERAL LENS DATA: MYTS3(  
U,3d) ]Zy&  
Surfaces                :                3 sfC@*Y2XT  
Stop                    :                1 Mh
H);fn  
System Aperture         : Object Space NA = 0.12 XZ@>]P  
Glass Catalogs          : Schott s, -*q
}  
Ray Aiming              : Paraxial Reference, Cache On )[DpK=[N^p  
X Pupil shift          :               0
H^v{Vo  
Y Pupil shift          :               0 `X
qy  
Z Pupil shift          :               0 N<bD  
Apodization             : Gaussian, factor =   1.00000E+000 /'+4vXc@  
************************************************************* M+UMR+K  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) w)<4>(D  
Effective Focal Length  :        1.639158 (in image space) L{K*~B-p  
************************************************************* Y\>\[*.v  
Back Focal Length       :       -1.061568 5V rcR=?O  
Total Track             :           4.318 !pS~'E&q  
Image Space F/#         :        3.417255 )]]|d  
Paraxial Working F/#    :        2.950535 ^8\Y`Z0%  
Working F/#             :        2.961912 g _x\T+=  
Image Space NA          :       0.1670788 eH `t \n  
Object Space NA         :            0.12 b.(XS?4o  
Stop Radius             :       0.2398355 ;q&Z9lm  
Paraxial Image Height   :               0 |QqWVelc  
Paraxial Magnification  :               0 Wbs^(iUU}  
Entrance Pupil Diameter :       0.4796709 Hc /wta  
Entrance Pupil Position :               0 !pV<n  
Exit Pupil Diameter     :        2.511155 vK`S!7x'&  
Exit Pupil Position     :        7.420935 RhyegD  
Field Type              : Angle in degrees N  I3(  
Maximum Field           :               0 \y,;Cfl<  
Primary Wave            :            1.31 &X7ttB"#h  
Lens Units              :   Millimeters S r[IoF)  
Angular Magnification   :               0 o5V`'[c  
^s.oZj q  
Fields          : 1 @6[x%j/!bt  
Field Type: Angle in degrees (mY(\mu}  
#        X-Value        Y-Value         Weight eAU"fu6d  
1       0.000000       0.000000       1.000000 u-1@~Z  
%y3:SUOdx  
Vignetting Factors hF9B?@n?B  
#       VDX       VDY       VCX       VCY       VAN o8m
o=V4j  
1  0.000000  0.000000  0.000000  0.000000  0.000000 |H<|{{E  
Rgs3A)[`d/  
Wavelengths     : 1 4Z],+?.[  
Units: Microns }P16Xb)p  
#          Value         Weight ZG!x$yi$  
1       1.310000       1.000000 SUSc  
tc5M$b3^2  
CARDINAL POINTS: 7ia"
u+Y  
4g S[D  
Object space positions are measured with respect to surface 1. d[yrNB6|  
Image space positions are measured with respect to the image surface. "
{mt?  
The index in both the object space and image space is considered. }1@n(#|c  
 s"#CkG  
                          Object Space         Image Space ?#U0eb5u  
W = 1.310000 (Primary) 8R BDJ  
************************************************************ ^CO#QnB @  
Focal Length          :           -1.639015            1.639015 E#8J+7  
************************************************************ rkbl/py  
Focal Planes          :            0.313078           -1.159568 =tLU]  
Principal Planes      :            1.952094           -2.798584 A"`L~|&  
Anti-Principal Planes :           -1.325937            0.479447 O5c_\yv=  
Nodal Planes          :            1.952094           -2.798584 6_pDe  
Anti-Nodal Planes     :           -1.325937            0.479447 Xk 5oybDI  
KhLg*EL  
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