[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？ '@ (WT~g  
一下是我的Prescription Data数据： 8;-a_VjA)  
GENERAL LENS DATA: /mo
4Q?^  
$ R,7#7bG  
Surfaces                :                3 '8}*erAg  
Stop                    :                1 9JJ(KY  
System Aperture         : Object Space NA = 0.12 89k9#i X  
Glass Catalogs          : Schott E+]g
C  
Ray Aiming              : Paraxial Reference, Cache On m9a(f>C  
X Pupil shift          :               0 'k{pWfn=<  
Y Pupil shift          :               0 !#5RP5,,Y  
Z Pupil shift          :               0
w8%<O^wN,  
Apodization             : Gaussian, factor =   1.00000E+000 BXnSkT7  
************************************************************* CES^ c-. k  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) DnMfHG[<  
Effective Focal Length  :        1.639158 (in image space) t+|c)"\5h  
************************************************************* [wj&.I{^s  
Back Focal Length       :       -1.061568 #Bj.#5  
Total Track             :           4.318 0x4p!5  
Image Space F/#         :        3.417255 aP>%iRk'J!  
Paraxial Working F/#    :        2.950535 -;Y*;xe  
Working F/#             :        2.961912 Q]uxZ;}aF  
Image Space NA          :       0.1670788 y.=ur,Nd  
Object Space NA         :            0.12 %J5zfNe)&  
Stop Radius             :       0.2398355 ?MHVkGD  
Paraxial Image Height   :               0 Ze~^+ EE  
Paraxial Magnification  :               0 \/xWsbG\  
Entrance Pupil Diameter :       0.4796709 PeEC|&x  
Entrance Pupil Position :               0 Pe6MDWR  
Exit Pupil Diameter     :        2.511155 4nN%5c~=  
Exit Pupil Position     :        7.420935 ' jf$3  
Field Type              : Angle in degrees J'G 6Z7  
Maximum Field           :               0 t,gKN^P_  
Primary Wave            :            1.31 pd?3_yU  
Lens Units              :   Millimeters )+'FTz` c  
Angular Magnification   :               0 /59jkcA+  
=6y4*f  
Fields          : 1 /. k4Y  
Field Type: Angle in degrees !_3RdS  
#        X-Value        Y-Value         Weight KB0HM  
1       0.000000       0.000000       1.000000 wf)T-]e  
l{[{pAm  
Vignetting Factors "94e-Nx  
#       VDX       VDY       VCX       VCY       VAN swss#?.se  
1  0.000000  0.000000  0.000000  0.000000  0.000000 ,_,Z<X/
 
D(yU:^L  
Wavelengths     : 1 $b,o3eC  
Units: Microns &U^6N+l9  
#          Value         Weight u0(H!  
1       1.310000       1.000000 oKLL~X>!U  
Rf||(KC<  
CARDINAL POINTS: W3Oj6R  
Q*u4q-DE  
Object space positions are measured with respect to surface 1. A>8"8=C  
Image space positions are measured with respect to the image surface. ;7Cb!v1
 
The index in both the object space and image space is considered. kTZ`RW&0  
uH!uSB2  
                          Object Space         Image Space DgQw`D)+  
W = 1.310000 (Primary) #EQwl6  
************************************************************ "xe %  IS  
Focal Length          :           -1.639015            1.639015 KAVe~j"  
************************************************************ Wnm?a!j5  
Focal Planes          :            0.313078           -1.159568 \bNN]=  
Principal Planes      :            1.952094           -2.798584 *8{PoD   
Anti-Principal Planes :           -1.325937            0.479447 A Ch!D>C1  
Nodal Planes          :            1.952094           -2.798584 SIQ7oxS4  
Anti-Nodal Planes     :           -1.325937            0.479447 fTQRn  
?WyL
|;b*  
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