[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？ !")WZq^`  
一下是我的Prescription Data数据： &\c5!xQ9*  
GENERAL LENS DATA: X+%u(>>  
M_; w%FV  
Surfaces                :                3 hRLKb}  
Stop                    :                1 cPJ7E  
System Aperture         : Object Space NA = 0.12 ,$ mLL  
Glass Catalogs          : Schott ^9s"FdB]24  
Ray Aiming              : Paraxial Reference, Cache On uD[^K1Ag]^  
X Pupil shift          :               0 5)8.  
Y Pupil shift          :               0 W%WC(/hor  
Z Pupil shift          :               0 6$DG.p
 
Apodization             : Gaussian, factor =   1.00000E+000 aTX]+tBoe  
************************************************************* ^7<[}u;qF  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) 4Lw'v:(  
Effective Focal Length  :        1.639158 (in image space) ij!*CTG  
************************************************************* g&XhQ.aa  
Back Focal Length       :       -1.061568 {n6\g]p3  
Total Track             :           4.318 zG<0CZQ8  
Image Space F/#         :        3.417255 TRo4I{L6S  
Paraxial Working F/#    :        2.950535 |w4(rs-  
Working F/#             :        2.961912 u,\xok"  
Image Space NA          :       0.1670788 p[b7E`7  
Object Space NA         :            0.12 -C=]n<ak  
Stop Radius             :       0.2398355 Ir^BC!<2>  
Paraxial Image Height   :               0 }d@LSaM  
Paraxial Magnification  :               0 }Py<qXH  
Entrance Pupil Diameter :       0.4796709 ~%/'0}F  
Entrance Pupil Position :               0 ThbP;CzI#  
Exit Pupil Diameter     :        2.511155 y6bjJ}  
Exit Pupil Position     :        7.420935 YyG~#6aCh  
Field Type              : Angle in degrees 48;~bVr}  
Maximum Field           :               0 4sI3(z)9H  
Primary Wave            :            1.31 Up'."w_zE  
Lens Units              :   Millimeters {;\%!I  
Angular Magnification   :               0 D)h["z|F  
7f[8ED[4  
Fields          : 1 E $<;@  
Field Type: Angle in degrees ]yw_n^@  
#        X-Value        Y-Value         Weight 8.PXTOhVL  
1       0.000000       0.000000       1.000000 vrQFx~ZztH  
juR  
Vignetting Factors $,g 3*A  
#       VDX       VDY       VCX       VCY       VAN 5=*@l  
1  0.000000  0.000000  0.000000  0.000000  0.000000 t ]71  
F>TYVxQ  
Wavelengths     : 1 e W9)@nVJ  
Units: Microns Q.*'H_Y  
#          Value         Weight O~nBz):2  
1       1.310000       1.000000 .&Y,D-h}7|  
@ca#U-:g  
CARDINAL POINTS: tnA_!$Y a  
/E;;j9  
Object space positions are measured with respect to surface 1. MM=W9#  
Image space positions are measured with respect to the image surface. B#;s(O  
The index in both the object space and image space is considered. VyRW'  
(R,NV3m?w  
                          Object Space         Image Space 3
KDu!w@  
W = 1.310000 (Primary) _!|=AIX  
************************************************************ "9TxK6  
Focal Length          :           -1.639015            1.639015 F
]hx  
************************************************************ ?G2qlna  
Focal Planes          :            0.313078           -1.159568 9@kcK  
Principal Planes      :            1.952094           -2.798584 8+=p8e~An  
Anti-Principal Planes :           -1.325937            0.479447 iXt4|0  
Nodal Planes          :            1.952094           -2.798584 ScM}m  
Anti-Nodal Planes     :           -1.325937            0.479447 Ym3 "  
e?_c[`sg  
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