[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？ /tx]5`#@7]  
一下是我的Prescription Data数据： I(L,8n5  
GENERAL LENS DATA: S]e|"n~@  
|P HT694Uz  
Surfaces                :                3 OUPUixz2Z  
Stop                    :                1 {tuYs:  
System Aperture         : Object Space NA = 0.12 .PIL +x*]N  
Glass Catalogs          : Schott np"\19^  
Ray Aiming              : Paraxial Reference, Cache On ~F|+o}a`  
X Pupil shift          :               0 A@!qv#'  
Y Pupil shift          :               0 zII|9
y  
Z Pupil shift          :               0 u"cV%(#  
Apodization             : Gaussian, factor =   1.00000E+000 +K:
Dx!9  
************************************************************* +ZaSM~   
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) r;.yz I  
Effective Focal Length  :        1.639158 (in image space) JW83Tp8[8  
************************************************************* ,GbR!j@6  
Back Focal Length       :       -1.061568 <sGVR5NR  
Total Track             :           4.318 )1J R#  
Image Space F/#         :        3.417255 _lJ!R:*  
Paraxial Working F/#    :        2.950535 sk<3`x+  
Working F/#             :        2.961912 ^B.5GK)!  
Image Space NA          :       0.1670788 by1<[$8r  
Object Space NA         :            0.12 WTQ\PANAaR  
Stop Radius             :       0.2398355 v!-/&}W)1  
Paraxial Image Height   :               0 .LnGL]/  
Paraxial Magnification  :               0 ;s= l52  
Entrance Pupil Diameter :       0.4796709 T\6dm/5  
Entrance Pupil Position :               0 |/|5UiX7  
Exit Pupil Diameter     :        2.511155 5,lEx1{_  
Exit Pupil Position     :        7.420935 WtsFz*`)y  
Field Type              : Angle in degrees 7?!d^$B  
Maximum Field           :               0 ?DS@e@lx  
Primary Wave            :            1.31 .]Y$o^mf  
Lens Units              :   Millimeters B?gOHG*vd>  
Angular Magnification   :               0 x*\Y)9Vgy  
k<nZ+! M  
Fields          : 1 ~|DUt  
Field Type: Angle in degrees wtLO!=B  
#        X-Value        Y-Value         Weight CAig]=2'  
1       0.000000       0.000000       1.000000 Wa>}wA=v  
"rALt~AX  
Vignetting Factors \_VA50  
#       VDX       VDY       VCX       VCY       VAN ~k-y &<UR  
1  0.000000  0.000000  0.000000  0.000000  0.000000 Fbr;{T .
 
b4%??"&<Y  
Wavelengths     : 1 U/66L+1  
Units: Microns  L^/5ux  
#          Value         Weight }1L4"}L.  
1       1.310000       1.000000 R3)~?X1n  
3)t.p>VgO  
CARDINAL POINTS: a_^\=&?'  
ehGLk7@7&  
Object space positions are measured with respect to surface 1. c)6m$5]  
Image space positions are measured with respect to the image surface. lne4-(DJ  
The index in both the object space and image space is considered. ,a{P4Bq  
RtkEGxw*^  
                          Object Space         Image Space DD+7V@  
W = 1.310000 (Primary) ?um;s-x)  
************************************************************ rQ{7j!Im  
Focal Length          :           -1.639015            1.639015 .FP$m?  
************************************************************ ^&9zw\x;z  
Focal Planes          :            0.313078           -1.159568 /e5O"@  
Principal Planes      :            1.952094           -2.798584 G=s}12/Z"{  
Anti-Principal Planes :           -1.325937            0.479447 p;`>e>$  
Nodal Planes          :            1.952094           -2.798584 [t m_Mg  
Anti-Nodal Planes     :           -1.325937            0.479447 pTth}JM>  
hIYNhZv  
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