[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？ XFKe6:  
一下是我的Prescription Data数据： Vw:.'-Oi  
GENERAL LENS DATA: ]=!wMn**  
`ECT8  
Surfaces                :                3 :_V9Jw
u  
Stop                    :                1 d"o5uo  
System Aperture         : Object Space NA = 0.12 kk#%x#L[  
Glass Catalogs          : Schott A?V}$PTlx  
Ray Aiming              : Paraxial Reference, Cache On ^=`7]E[p  
X Pupil shift          :               0 +A%|.;  
Y Pupil shift          :               0 Q46^i7=  
Z Pupil shift          :               0 CAg~K[  
Apodization             : Gaussian, factor =   1.00000E+000 'Dw+k;RH  
************************************************************* qM78s>\-h  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) (37dD!  
Effective Focal Length  :        1.639158 (in image space) 7niZ`doBA  
************************************************************* uqy&PS  
Back Focal Length       :       -1.061568 zGgPW  
Total Track             :           4.318 S"hA@j  
Image Space F/#         :        3.417255 35=kZXwG+4  
Paraxial Working F/#    :        2.950535 PJ}d- 
 
Working F/#             :        2.961912 yTJ Eo\g/@  
Image Space NA          :       0.1670788 ZD!?mR+-  
Object Space NA         :            0.12 -
#@l`kt  
Stop Radius             :       0.2398355 c"D
%c(:4|  
Paraxial Image Height   :               0 :Ywb  
Paraxial Magnification  :               0 h|~I'M]*  
Entrance Pupil Diameter :       0.4796709 `|kW%L4  
Entrance Pupil Position :               0 8R|!$P  
Exit Pupil Diameter     :        2.511155 `%S 35x9  
Exit Pupil Position     :        7.420935 I<E~=  
Field Type              : Angle in degrees NzS(,F  
Maximum Field           :               0 ]M3V]
m  
Primary Wave            :            1.31 D!7-(3R  
Lens Units              :   Millimeters >s dT=6v  
Angular Magnification   :               0
Gbj^oo  

bmCp:
6  
Fields          : 1 ozaM!ee\z  
Field Type: Angle in degrees <c'0-=  
#        X-Value        Y-Value         Weight $[f-{B{>*  
1       0.000000       0.000000       1.000000 j-]`;&L  
ri.}G  
Vignetting Factors  T.d1?  
#       VDX       VDY       VCX       VCY       VAN )LC"rSNx%  
1  0.000000  0.000000  0.000000  0.000000  0.000000 H@,h$$  
P^'TI[\L9  
Wavelengths     : 1 'Fq+\J#%  
Units: Microns T'6MAxEZUq  
#          Value         Weight  iYaS  
1       1.310000       1.000000 SG$V%z"e  
e|-&h `[  
CARDINAL POINTS: deLLqdZa  
r=}v` R&  
Object space positions are measured with respect to surface 1. '[WVP=M<XV  
Image space positions are measured with respect to the image surface. m&MAA^I  
The index in both the object space and image space is considered. HQkK8'\LP  
j_3`J8WwF  
                          Object Space         Image Space bW-sTGjRD  
W = 1.310000 (Primary) gOy
;6\/  
************************************************************ X+2uM+  
Focal Length          :           -1.639015            1.639015 NHaY&\  
************************************************************ ldFR%v>9  
Focal Planes          :            0.313078           -1.159568 ;cEoc(<?  
Principal Planes      :            1.952094           -2.798584 J?#Xy9dz  
Anti-Principal Planes :           -1.325937            0.479447 5Z@0XI  
Nodal Planes          :            1.952094           -2.798584 !i>d04u`%  
Anti-Nodal Planes     :           -1.325937            0.479447 \s?8}k  
rP{J
ep!  
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