[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？ rbS=Ewk  
一下是我的Prescription Data数据： 0x/V1?gm  
GENERAL LENS DATA: H#`?toS  
?6]ZQ\,  
Surfaces                :                3 I~6 ;9TlQ  
Stop                    :                1 :Lzj'Ij  
System Aperture         : Object Space NA = 0.12 p6\9H

G  
Glass Catalogs          : Schott u"|nu!p`  
Ray Aiming              : Paraxial Reference, Cache On UVU*5U~  
X Pupil shift          :               0 g*AqFY7|  
Y Pupil shift          :               0 LtIZgOd<  
Z Pupil shift          :               0 ebVfny$D  
Apodization             : Gaussian, factor =   1.00000E+000 _)" 5 gv  
************************************************************* 3yX^R^`  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) P#1y  
Effective Focal Length  :        1.639158 (in image space) \$UU/\  
************************************************************* tqf-,BLh  
Back Focal Length       :       -1.061568 "n-xsAG  
Total Track             :           4.318 "t`e68{Ls  
Image Space F/#         :        3.417255 /qze  
Paraxial Working F/#    :        2.950535 @V u[Tg}J  
Working F/#             :        2.961912 4f-C]N=  
Image Space NA          :       0.1670788 >R-$JrU.=  
Object Space NA         :            0.12 e]fC!>w(\  
Stop Radius             :       0.2398355 5Ozj&Zq  
Paraxial Image Height   :               0 ^i7a2< z  
Paraxial Magnification  :               0 Q{kuB+s  
Entrance Pupil Diameter :       0.4796709 C@W0fz  
Entrance Pupil Position :               0 Y" |U$  
Exit Pupil Diameter     :        2.511155 KJSy7F  
Exit Pupil Position     :        7.420935 7w({ GZ  
Field Type              : Angle in degrees gI{F"7fa=  
Maximum Field           :               0 M#|xj <p  
Primary Wave            :            1.31 h UDEjW@S  
Lens Units              :   Millimeters ArMe[t0$  
Angular Magnification   :               0 O-YE6u  
4TV9t"Dk+c  
Fields          : 1 Hc!_o`[{l  
Field Type: Angle in degrees $5O&[/L  
#        X-Value        Y-Value         Weight ?-i&6i6Y  
1       0.000000       0.000000       1.000000 9r}}
m0  
K~G^jAk+  
Vignetting Factors ~C+T|  
#       VDX       VDY       VCX       VCY       VAN ,)8Hl[y  
1  0.000000  0.000000  0.000000  0.000000  0.000000 ;kA2"c]m  
v\u+=}rl  
Wavelengths     : 1 4Qs#ws])  
Units: Microns }=5(*Vg  
#          Value         Weight WOoVVjMM  
1       1.310000       1.000000 <#i'3TUR  
vzPrG%Uu7g  
CARDINAL POINTS: %/p5C  
W'yICt(#G  
Object space positions are measured with respect to surface 1. ZN/")  
Image space positions are measured with respect to the image surface. BZsxf'eN'  
The index in both the object space and image space is considered. 6zSN?0c  
\WEC1+@  
                          Object Space         Image Space NKN!X/P  
W = 1.310000 (Primary) 14O/R3+  
************************************************************ ,P]{*uqGiB  
Focal Length          :           -1.639015            1.639015 |/Z4lcI  
************************************************************ E.brQx#}  
Focal Planes          :            0.313078           -1.159568 C_o.d~xm  
Principal Planes      :            1.952094           -2.798584 4}`MV.  
Anti-Principal Planes :           -1.325937            0.479447 ) Lv{  
Nodal Planes          :            1.952094           -2.798584 UlR7_  
Anti-Nodal Planes     :           -1.325937            0.479447 (;0]V+-  
NaIVKo  
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