[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？ o,7|=.-b  
一下是我的Prescription Data数据： Z(MZbzY7Hq  
GENERAL LENS DATA: `OW'AS |  
be+-p  
Surfaces                :                3 6
H|SiO9  
Stop                    :                1 01.q9AGy  
System Aperture         : Object Space NA = 0.12 MJ}{Q1|*  
Glass Catalogs          : Schott HPtMp#`T  
Ray Aiming              : Paraxial Reference, Cache On P(aBJ*((~  
X Pupil shift          :               0 |"*P`C=  
Y Pupil shift          :               0 &y? |$p\;/  
Z Pupil shift          :               0 EyK!'9~a  
Apodization             : Gaussian, factor =   1.00000E+000 gj^)T_E_  
************************************************************* @76}d  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) dz^HN`AlzC  
Effective Focal Length  :        1.639158 (in image space) hz/mNDE]  
************************************************************* S{^x]h|?  
Back Focal Length       :       -1.061568 ,^9+G"H:I  
Total Track             :           4.318 *7AB0y0k  
Image Space F/#         :        3.417255 aO{@.  
Paraxial Working F/#    :        2.950535 P^te
 
Working F/#             :        2.961912 8a6.77c  
Image Space NA          :       0.1670788 SdnnXEB7  
Object Space NA         :            0.12 ;hQ[-  
Stop Radius             :       0.2398355 u`v&URM  
Paraxial Image Height   :               0 3zsp6kV  
Paraxial Magnification  :               0 @`[e1KQ  
Entrance Pupil Diameter :       0.4796709 [RBSUOF  
Entrance Pupil Position :               0 &eMd^l}:#  
Exit Pupil Diameter     :        2.511155 i!YfR]"}  
Exit Pupil Position     :        7.420935 6 IvAs-%W  
Field Type              : Angle in degrees 8g-u  
Maximum Field           :               0 (wu'FFJp#  
Primary Wave            :            1.31 d(^8#4  
Lens Units              :   Millimeters []>rYZ9bv  
Angular Magnification   :               0 N82 6xvA  
;1&"]N%  
Fields          : 1 V Rv4p5  
Field Type: Angle in degrees JSUD$|RiJ  
#        X-Value        Y-Value         Weight i*$+>3Q-  
1       0.000000       0.000000       1.000000 .>W [  
vjX,7NY?  
Vignetting Factors .=:f]fs  
#       VDX       VDY       VCX       VCY       VAN i ;B^I8  
1  0.000000  0.000000  0.000000  0.000000  0.000000 gdIk%m4  
+.Vh<:?
 
Wavelengths     : 1 xoVd[c!   
Units: Microns 
1gK|n  
#          Value         Weight G@P;#l`(D  
1       1.310000       1.000000 #`y[75<n  
n[>hJ6  
CARDINAL POINTS: du$lS':`  
h1S)B|~8  
Object space positions are measured with respect to surface 1. Rxdj}xy  
Image space positions are measured with respect to the image surface. )2c]Z|  
The index in both the object space and image space is considered. Z"c-Ly{vEj  
=|J*9z;  
                          Object Space         Image Space {N]WVp*R  
W = 1.310000 (Primary) 4L>8RiiQE;  
************************************************************  eFsl  
Focal Length          :           -1.639015            1.639015 h GA2.{  
************************************************************ 4- QlIIf  
Focal Planes          :            0.313078           -1.159568 J4eU6W+{  
Principal Planes      :            1.952094           -2.798584 0d2RB^"i  
Anti-Principal Planes :           -1.325937            0.479447 <Y6Vfee,&  
Nodal Planes          :            1.952094           -2.798584 E^J &?
-  
Anti-Nodal Planes     :           -1.325937            0.479447 -aBhN~  
z#G\D5yX[*  
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