[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？ ]I:h4hgw  
一下是我的Prescription Data数据： 7N8a48$8  
GENERAL LENS DATA: _FxQl]@  
d)1Pl3+  
Surfaces                :                3 A(1
dq  
Stop                    :                1 pxV@fH+`  
System Aperture         : Object Space NA = 0.12 =z4kK_?F,  
Glass Catalogs          : Schott d>h
Lnz1O  
Ray Aiming              : Paraxial Reference, Cache On cyXnZs ?|  
X Pupil shift          :               0 /SKgN{tWe  
Y Pupil shift          :               0 !Ct'H1J-  
Z Pupil shift          :               0 _ lE d8Cb  
Apodization             : Gaussian, factor =   1.00000E+000 _ipY;  
************************************************************* Om5+j:YM  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) Al^h^ 9tJ  
Effective Focal Length  :        1.639158 (in image space) ;@s'JSPt  
************************************************************* d)'J:  
Back Focal Length       :       -1.061568 l'FNp  
Total Track             :           4.318 7q@>d(xho  
Image Space F/#         :        3.417255 f0ME$:2  
Paraxial Working F/#    :        2.950535 ;
t5e]  
Working F/#             :        2.961912 8dCa@r&tz  
Image Space NA          :       0.1670788 dPb@[k  
Object Space NA         :            0.12 o
l8|  
Stop Radius             :       0.2398355 L
@x#:s=  
Paraxial Image Height   :               0 ByivV2qd{  
Paraxial Magnification  :               0 ~T:L0||.%9  
Entrance Pupil Diameter :       0.4796709 i1ss}JJp*  
Entrance Pupil Position :               0 ]:n! \G  
Exit Pupil Diameter     :        2.511155
]#P>wW  
Exit Pupil Position     :        7.420935 |YWX.-aeo  
Field Type              : Angle in degrees {Ax{N  
Maximum Field           :               0 50HRgoP5Y  
Primary Wave            :            1.31 YdF\*tZ  
Lens Units              :   Millimeters ]}A3Pm- t*  
Angular Magnification   :               0 |P`:NAf2  
VhX~sJ1%Gp  
Fields          : 1 MB!$s_~o#L  
Field Type: Angle in degrees woyeKOr  
#        X-Value        Y-Value         Weight ZuVes?&j  
1       0.000000       0.000000       1.000000 Xw]L'+V=  
gQlL0jAV  
Vignetting Factors =plU3D2  
#       VDX       VDY       VCX       VCY       VAN yGX"1Fb?;x  
1  0.000000  0.000000  0.000000  0.000000  0.000000 FWl'='5L  
RJ~I?{yR0[  
Wavelengths     : 1 [.LbX`K:  
Units: Microns +@jX|  
#          Value         Weight 'J(B{B7|  
1       1.310000       1.000000 U9%#(
T$  
HWxwG'EEY,  
CARDINAL POINTS: 5|Hz$oU  
xq\A TON  
Object space positions are measured with respect to surface 1. B<6Ye9zuG  
Image space positions are measured with respect to the image surface. :}3;z'2]l  
The index in both the object space and image space is considered. (f>~+-IL  
Hl b%/&  
                          Object Space         Image Space r0fEW9wL  
W = 1.310000 (Primary) 9,>u,  
************************************************************ \K%A}gnHe  
Focal Length          :           -1.639015            1.639015 0PT\/imgN  
************************************************************ %eQw\o,a  
Focal Planes          :            0.313078           -1.159568 ]}HuK#  
Principal Planes      :            1.952094           -2.798584 0pl |  
Anti-Principal Planes :           -1.325937            0.479447 ,{VC(/d  
Nodal Planes          :            1.952094           -2.798584 !/wR[`s9w  
Anti-Nodal Planes     :           -1.325937            0.479447 }.74w0~0^  
%:vMD  
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！