[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？ K/DH / r  
一下是我的Prescription Data数据： k9cK bf@  
GENERAL LENS DATA: =1O?jrl~q  
R j-jAH  
Surfaces                :                3 x 96}#0'  
Stop                    :                1 fH&zR#T7U4  
System Aperture         : Object Space NA = 0.12 |n)<4%i8J  
Glass Catalogs          : Schott T
)`gm{T  
Ray Aiming              : Paraxial Reference, Cache On -P2 @mx%  
X Pupil shift          :               0 ^<!Ia  
Y Pupil shift          :               0 X@cSP7b  
Z Pupil shift          :               0 fTTm$,f5N  
Apodization             : Gaussian, factor =   1.00000E+000 !TGr.R  
************************************************************* {798=pC<.  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) 4yhcK&  
Effective Focal Length  :        1.639158 (in image space) jn~!V!++  
************************************************************* Vfb<o"BQk  
Back Focal Length       :       -1.061568 +9TV:T  
Total Track             :           4.318 g083J}08  
Image Space F/#         :        3.417255 (:JjQ`i  
Paraxial Working F/#    :        2.950535 8*vFdoE_oO  
Working F/#             :        2.961912 O /vWd"  
Image Space NA          :       0.1670788 Ac J>$L)  
Object Space NA         :            0.12 )TM!ms+K  
Stop Radius             :       0.2398355
m.!wsw  
Paraxial Image Height   :               0 iEe#aO"D!  
Paraxial Magnification  :               0 ad9EG#mD#  
Entrance Pupil Diameter :       0.4796709 Bf/|{@  
Entrance Pupil Position :               0 )t5;d  
Exit Pupil Diameter     :        2.511155 % ^e@`0L  
Exit Pupil Position     :        7.420935 O6/xPeak  
Field Type              : Angle in degrees wBLsz/  
Maximum Field           :               0 8'+7i8e  
Primary Wave            :            1.31 uO"y`$C$_  
Lens Units              :   Millimeters <M=';h^w2  
Angular Magnification   :               0 `6UtxJSx  
[Q|M/|mnR1  
Fields          : 1 b##1hm~+9  
Field Type: Angle in degrees =Aj"j-r&{  
#        X-Value        Y-Value         Weight h+5@I%WX  
1       0.000000       0.000000       1.000000 |J\,F.{'  
Ohi D  
Vignetting Factors ^zHRSO  
#       VDX       VDY       VCX       VCY       VAN 2?*||c==*  
1  0.000000  0.000000  0.000000  0.000000  0.000000 BK*z 4m  
wz h.$?~  
Wavelengths     : 1 72u db^  
Units: Microns \<=IMa0  
#          Value         Weight *{Yh6{  
1       1.310000       1.000000 6A.P6DW  
j!7Qw 8  
CARDINAL POINTS: [#>{4qY2  
(m/aV  
Object space positions are measured with respect to surface 1. w1cw1xX*  
Image space positions are measured with respect to the image surface. ldYeX+J _  
The index in both the object space and image space is considered. svqvG7  
Nkx0CG*  
                          Object Space         Image Space i0iez9B  
W = 1.310000 (Primary) I.-v?1>,  
************************************************************ v[smQO  
Focal Length          :           -1.639015            1.639015 Ajg\aof0{  
************************************************************ <$Ztik1  
Focal Planes          :            0.313078           -1.159568 (2d3jQN`  
Principal Planes      :            1.952094           -2.798584 1g~y]iQ  
Anti-Principal Planes :           -1.325937            0.479447 #>XeR>T  
Nodal Planes          :            1.952094           -2.798584 R2CQXhiJ  
Anti-Nodal Planes     :           -1.325937            0.479447 <&6u]uKrW  
viJJ e'\2  
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