[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？ jJe?pT]o  
一下是我的Prescription Data数据： uX+ YH  
GENERAL LENS DATA: XM:\N$
tg  
v=E(U4v9e  
Surfaces                :                3 oN=>U"<\1  
Stop                    :                1 vm8ER,IW)  
System Aperture         : Object Space NA = 0.12 &LHS<Nv^:  
Glass Catalogs          : Schott A0H6}53, $  
Ray Aiming              : Paraxial Reference, Cache On x\K,@  
X Pupil shift          :               0 [(Ihue  
Y Pupil shift          :               0 <!derr-K  
Z Pupil shift          :               0 G@o\D-$  
Apodization             : Gaussian, factor =   1.00000E+000 ]eo%eaA   
************************************************************* )^j62uv  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) r|Q/:UV?w  
Effective Focal Length  :        1.639158 (in image space) nc.:Wm6Mj  
************************************************************* oGz5ZDa#  
Back Focal Length       :       -1.061568 Up\ k67  
Total Track             :           4.318 1abQoe  
Image Space F/#         :        3.417255 vg*~t3{L  
Paraxial Working F/#    :        2.950535 \ 9#X]H  
Working F/#             :        2.961912 N
)  
Image Space NA          :       0.1670788 ?I;PJj  
Object Space NA         :            0.12 TECp!`)j"  
Stop Radius             :       0.2398355 8T3Nz8Q7  
Paraxial Image Height   :               0 oe[f2?-  
Paraxial Magnification  :               0 4z,/0  
Entrance Pupil Diameter :       0.4796709 \n^;r|J7k  
Entrance Pupil Position :               0 =s,}@iqNO4  
Exit Pupil Diameter     :        2.511155 -mG
 ,_}F  
Exit Pupil Position     :        7.420935 >lF@M-
 
Field Type              : Angle in degrees kp^q}iS  
Maximum Field           :               0 =&WH9IKz  
Primary Wave            :            1.31 JHg y&/  
Lens Units              :   Millimeters R^@  
Angular Magnification   :               0 ?{wD%58^oG  
Te7xj8<  
Fields          : 1 b8|<O:]Hp  
Field Type: Angle in degrees Pdk#"H-j  
#        X-Value        Y-Value         Weight NF'<8{~  
1       0.000000       0.000000       1.000000 %\Mc6  
hY|-l%2f  
Vignetting Factors /&zlC{:G92  
#       VDX       VDY       VCX       VCY       VAN VI?kbqjo  
1  0.000000  0.000000  0.000000  0.000000  0.000000 +nL#c{  
"pc t#  
Wavelengths     : 1 >FqU=Q  
Units: Microns 5jHr?
C  
#          Value         Weight !HKW_m^3J  
1       1.310000       1.000000 zEYQZywc  
0N_u6*@  
CARDINAL POINTS: 'ji|'x T  
a7jE*%f9  
Object space positions are measured with respect to surface 1. :jFZz%   
Image space positions are measured with respect to the image surface. kzC4V  
The index in both the object space and image space is considered. +QeA*L$~  
f(T`(pX0V  
                          Object Space         Image Space +-qa7  
W = 1.310000 (Primary) 6_>(9&g`zV  
************************************************************ VXl|AA<OG  
Focal Length          :           -1.639015            1.639015 o,{]<Sm  
************************************************************ `bF4/iBW  
Focal Planes          :            0.313078           -1.159568 _}tPtHPa/  
Principal Planes      :            1.952094           -2.798584 :-oMkBS  
Anti-Principal Planes :           -1.325937            0.479447 1,+swFSN  
Nodal Planes          :            1.952094           -2.798584 =ba1::18  
Anti-Nodal Planes     :           -1.325937            0.479447 mQ2=t%  
ubMN  
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