[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？ IEoR7:  
一下是我的Prescription Data数据： nUud?F^_  
GENERAL LENS DATA: K;y\[2;}e,  
!|<f%UO  
Surfaces                :                3 0|s$vqc  
Stop                    :                1 |t65#1  
System Aperture         : Object Space NA = 0.12 ( X 'FQ  
Glass Catalogs          : Schott Ec*--]j*c  
Ray Aiming              : Paraxial Reference, Cache On ay:\P.`5)  
X Pupil shift          :               0 fteyG$-s  
Y Pupil shift          :               0 bpF@}#fT  
Z Pupil shift          :               0 0^!,[oh6*  
Apodization             : Gaussian, factor =   1.00000E+000 O5TK&j  
************************************************************* )|Vg

/S  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) 8?j&{G  
Effective Focal Length  :        1.639158 (in image space) or!D  
************************************************************* GrLM${G  
Back Focal Length       :       -1.061568 "`jZ(+  
Total Track             :           4.318 BBU84s[  
Image Space F/#         :        3.417255 K*Nb_|~  
Paraxial Working F/#    :        2.950535 yToT7 X7F7  
Working F/#             :        2.961912 HV*:<2P%D  
Image Space NA          :       0.1670788 qN1e{T8u  
Object Space NA         :            0.12 GwMUIevO_  
Stop Radius             :       0.2398355 XU;{28P  
Paraxial Image Height   :               0 nXM9Px!  
Paraxial Magnification  :               0 g`)/x\  
Entrance Pupil Diameter :       0.4796709 p9&gEW  
Entrance Pupil Position :               0 Nn,vdu{^2  
Exit Pupil Diameter     :        2.511155 lk*0c{_L  
Exit Pupil Position     :        7.420935 o]|oAN9  
Field Type              : Angle in degrees iO?gF  
Maximum Field           :               0 $dx1[V+_  
Primary Wave            :            1.31 ~b>nCP8q  
Lens Units              :   Millimeters 2pxWv )0  
Angular Magnification   :               0 s=q%:uCO  
p-T~x$"c|  
Fields          : 1 ~4=]%XYz  
Field Type: Angle in degrees _cxm}*}\#
 
#        X-Value        Y-Value         Weight g/U$!d_  
1       0.000000       0.000000       1.000000 Lem\UD$D`  
=#.8$oa^  
Vignetting Factors f gK2.;>  
#       VDX       VDY       VCX       VCY       VAN \]f5  
1  0.000000  0.000000  0.000000  0.000000  0.000000 P;L)1 g  
8"?Vcw&  
Wavelengths     : 1 gfdPx:7^  
Units: Microns vy{rwZ$  
#          Value         Weight
LM"W)S  
1       1.310000       1.000000 xI`Uk8-8  
o7c%\v[  
CARDINAL POINTS: ]Efh(Gb]  
pjX%LsX\  
Object space positions are measured with respect to surface 1. E,*JPK-A x  
Image space positions are measured with respect to the image surface. Q8;x9o@p  
The index in both the object space and image space is considered. b[{m>Fa+o#  
z^ aCQ3E  
                          Object Space         Image Space .KiPNTh'  
W = 1.310000 (Primary) Jo7fxWO_g  
************************************************************ abTDa6 /`v  
Focal Length          :           -1.639015            1.639015 :Bx+WW&P.i  
************************************************************ t5ny"k!  
Focal Planes          :            0.313078           -1.159568 +X* F<6mZ  
Principal Planes      :            1.952094           -2.798584 xVsa,EX b  
Anti-Principal Planes :           -1.325937            0.479447 (!3Yc:~RE  
Nodal Planes          :            1.952094           -2.798584 eHVdZ'%x  
Anti-Nodal Planes     :           -1.325937            0.479447 g( ]b\rj  
p~Yy"Ec;p  
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