[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？ ;}f {o^]'  
一下是我的Prescription Data数据： qzvht4  
GENERAL LENS DATA: eDP&W$s#  
+U J~/XV  
Surfaces                :                3 xLFMC?I  
Stop                    :                1 J`0dF<<{[y  
System Aperture         : Object Space NA = 0.12 [Q8Wy/o Q  
Glass Catalogs          : Schott +{=U!}3|  
Ray Aiming              : Paraxial Reference, Cache On >f
Hu  
X Pupil shift          :               0 z7XI`MZN^  
Y Pupil shift          :               0 *2-b&PQR{  
Z Pupil shift          :               0 Ig?9"{9p  
Apodization             : Gaussian, factor =   1.00000E+000 G$'UK  
************************************************************* v)O].Hd
 
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) nM&a2Z,T  
Effective Focal Length  :        1.639158 (in image space) q9{ h@y  
************************************************************* `u_MdB}<x;  
Back Focal Length       :       -1.061568 Y
KU|D32  
Total Track             :           4.318 <m~8pM  
Image Space F/#         :        3.417255 MHt ~ZVH  
Paraxial Working F/#    :        2.950535 "2-D[rYZ  
Working F/#             :        2.961912 mDp8JNJNE  
Image Space NA          :       0.1670788 ji4bz#/B0  
Object Space NA         :            0.12 |ITCw$T  
Stop Radius             :       0.2398355 >)NS U  
Paraxial Image Height   :               0 =2(52#pT  
Paraxial Magnification  :               0 J9tV|
0  
Entrance Pupil Diameter :       0.4796709 ( 1  
Entrance Pupil Position :               0 ztHx) !  
Exit Pupil Diameter     :        2.511155 J,:;\Xhl  
Exit Pupil Position     :        7.420935 QX}J
Q<8  
Field Type              : Angle in degrees 4HZXv
\$  
Maximum Field           :               0 R#y"SxD()  
Primary Wave            :            1.31 [OOQ0c~  
Lens Units              :   Millimeters PU%f`)  
Angular Magnification   :               0 )f^^hEIS  
AFBWiuwI3  
Fields          : 1 Nc[N 11?O  
Field Type: Angle in degrees LDU4 D  
#        X-Value        Y-Value         Weight 7Q Ns q  
1       0.000000       0.000000       1.000000 +Tx_q1/f5X  
tmBt[  
Vignetting Factors 9a+Y )?z  
#       VDX       VDY       VCX       VCY       VAN 9* 3;v;F  
1  0.000000  0.000000  0.000000  0.000000  0.000000 {"$[MYi:  
-e0[$v  
Wavelengths     : 1 >L "+8N6  
Units: Microns C,mfA%63  
#          Value         Weight T+RC#&>  
1       1.310000       1.000000 *]R5bj.!o  
Fkpaou  
CARDINAL POINTS: H0])>1sWB  
IaOR%Bg  
Object space positions are measured with respect to surface 1. m:0[as=  
Image space positions are measured with respect to the image surface. Qa:[iF  
The index in both the object space and image space is considered. FVL{KNW~i  
YuIF}mUr"  
                          Object Space         Image Space 9I<~t@q5e@  
W = 1.310000 (Primary) <ty]z!B  
************************************************************ W?kJ+1"(  
Focal Length          :           -1.639015            1.639015 w 2U302TZ  
************************************************************ `J03t\  
Focal Planes          :            0.313078           -1.159568 &\cS{35  
Principal Planes      :            1.952094           -2.798584 A*/8j\{n  
Anti-Principal Planes :           -1.325937            0.479447 za 7+xF  
Nodal Planes          :            1.952094           -2.798584 I7=A
!C"  
Anti-Nodal Planes     :           -1.325937            0.479447 \ %MsG  
q
7soV(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