[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？ D8r=Vf  
一下是我的Prescription Data数据： j?gscQ3  
GENERAL LENS DATA: k2t#O%_f  
idLCq^jnJ  
Surfaces                :                3 4&a,7uVer  
Stop                    :                1 {I"`
(  
System Aperture         : Object Space NA = 0.12 Lr;PESV  
Glass Catalogs          : Schott tw?\bB  
Ray Aiming              : Paraxial Reference, Cache On [T>a}}@  
X Pupil shift          :               0 pQ/ bIuq  
Y Pupil shift          :               0 C?47v4n-'  
Z Pupil shift          :               0 }+3IM1VTW{  
Apodization             : Gaussian, factor =   1.00000E+000 [7|j:!  
************************************************************* }ki}J>j|f  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) d%C:%d  
Effective Focal Length  :        1.639158 (in image space) Eg;xj@S<2  
************************************************************* U%)m [zAw  
Back Focal Length       :       -1.061568 gyx4='Q  
Total Track             :           4.318 ),#hBB`ZA  
Image Space F/#         :        3.417255 gXThdNU4G  
Paraxial Working F/#    :        2.950535 1p]Z9$Y  
Working F/#             :        2.961912 I[$SVPe#  
Image Space NA          :       0.1670788 di,?`  
Object Space NA         :            0.12 kV$$GLD\  
Stop Radius             :       0.2398355 SGUu\yS&s  
Paraxial Image Height   :               0 Gi*GFv%xB  
Paraxial Magnification  :               0 XDM~H  
Entrance Pupil Diameter :       0.4796709 wn-{Vkpm  
Entrance Pupil Position :               0 UC{Tmf  
Exit Pupil Diameter     :        2.511155 sM0o,l(5  
Exit Pupil Position     :        7.420935 Y\pRk6,  
Field Type              : Angle in degrees !?%'Fy6t  
Maximum Field           :               0 ]0yYMnqvr  
Primary Wave            :            1.31 xM6v0Ua  
Lens Units              :   Millimeters ctB(c`zcY  
Angular Magnification   :               0 e_{!8u.+  
-'jPue2\  
Fields          : 1 Il&}4#:  
Field Type: Angle in degrees 3$hbb6N%6.  
#        X-Value        Y-Value         Weight |m5 E%E
 
1       0.000000       0.000000       1.000000 5[{#/!LX)  
=O?#>3A}  
Vignetting Factors hExw}c  
#       VDX       VDY       VCX       VCY       VAN wWU5]v  
1  0.000000  0.000000  0.000000  0.000000  0.000000 5PXo1"n8T  
~BJ~]~0P`  
Wavelengths     : 1 xU5+"t~  
Units: Microns %C^%Oq_k  
#          Value         Weight Q#$#VT!F  
1       1.310000       1.000000 tEE1
`10Mt  
 :Ky *AI  
CARDINAL POINTS: QoVRZ$!p  
Zagj1OV|  
Object space positions are measured with respect to surface 1. 5?()o}VjAO  
Image space positions are measured with respect to the image surface. <m|\#Jw_V  
The index in both the object space and image space is considered. J/o$\8tiMw  
D" 4*&  
                          Object Space         Image Space (3;dtp>Xx  
W = 1.310000 (Primary) ^ew<|J2,B  
************************************************************ nfV32D|3  
Focal Length          :           -1.639015            1.639015 l`}Ag8Q  
************************************************************ cIIt ;q[  
Focal Planes          :            0.313078           -1.159568 k;?Oi?]  
Principal Planes      :            1.952094           -2.798584 dT9ekNQB  
Anti-Principal Planes :           -1.325937            0.479447 0B;cQSH!q  
Nodal Planes          :            1.952094           -2.798584 +.RC{o,  
Anti-Nodal Planes     :           -1.325937            0.479447 yQXHEB  
(^Q:zU  
我用*号，标出了需要注意的地方，请高手指教！

慢慢理解

我也不会先看看再说!~

看的我头晕了,可能是感冒的缘故吧,以后有机会再探讨

等待高手帮忙吧 我也不会!

帮顶！！！！！！！！！！！！！！1

各位指点一下吧，自己顶起来！