[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？ {B.]w9  
一下是我的Prescription Data数据： 8-ssiiJ}gh  
GENERAL LENS DATA: n
0pe7/Ai  
HPKyAcS\  
Surfaces                :                3 =_J<thp  
Stop                    :                1 vP?S0>gh  
System Aperture         : Object Space NA = 0.12 Yj\yO(o/  
Glass Catalogs          : Schott vh8Kd' y  
Ray Aiming              : Paraxial Reference, Cache On Xy<f_  
X Pupil shift          :               0 ! hr@{CD  
Y Pupil shift          :               0 Gx_e\fe-/  
Z Pupil shift          :               0 4>C=:w  
Apodization             : Gaussian, factor =   1.00000E+000 |7x^@i9w  
************************************************************* *8H;KGe=  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) #%"
TU,[+  
Effective Focal Length  :        1.639158 (in image space) EsB'nf r  
************************************************************* 7`@?3?  
Back Focal Length       :       -1.061568 5udoZ>T  
Total Track             :           4.318 NV4W2thYo  
Image Space F/#         :        3.417255 !!%nl_I
(  
Paraxial Working F/#    :        2.950535 ldvxYq<:  
Working F/#             :        2.961912 jdf)bO(9#  
Image Space NA          :       0.1670788 SfSEA^@|  
Object Space NA         :            0.12 6G$tYfX  
Stop Radius             :       0.2398355 H)aC'M^
 
Paraxial Image Height   :               0 ^>{;9lo<  
Paraxial Magnification  :               0 g*r;( H>e  
Entrance Pupil Diameter :       0.4796709 `1<3Hu_  
Entrance Pupil Position :               0 %E7.$Gj%  
Exit Pupil Diameter     :        2.511155 3|r!*+.  
Exit Pupil Position     :        7.420935 aB6LAb2z;T  
Field Type              : Angle in degrees [<a%\:c m4  
Maximum Field           :               0 0a6z"K}  
Primary Wave            :            1.31 C,vc aC?  
Lens Units              :   Millimeters N:jiZ)  
Angular Magnification   :               0 .r%|RWs6W  
>1pH 91c'  
Fields          : 1 oe|<xWu  
Field Type: Angle in degrees Yf)|ws?!  
#        X-Value        Y-Value         Weight SSbK[aR  
1       0.000000       0.000000       1.000000 <L ( =  
GiO#1gA  
Vignetting Factors Rn_W|"  
#       VDX       VDY       VCX       VCY       VAN -U;LiO;N  
1  0.000000  0.000000  0.000000  0.000000  0.000000 Xb:BIp!e  
Fd,+(i D  
Wavelengths     : 1 MGyB8(  
Units: Microns ~2DV{dyj  
#          Value         Weight FDs^S)B  
1       1.310000       1.000000 y&=19A#  
8Pr7aT:,  
CARDINAL POINTS: l%U_iqL&  
(My$@l973  
Object space positions are measured with respect to surface 1. yP9wYF^A\  
Image space positions are measured with respect to the image surface. L0|hc  
The index in both the object space and image space is considered. J}_Dpb[L  
qq7X",s  
                          Object Space         Image Space >AX~c jo  
W = 1.310000 (Primary) O0(Q0Ko  
************************************************************ yO,`"Dc_0  
Focal Length          :           -1.639015            1.639015 ~TFYlV  
************************************************************ [xp,&  
Focal Planes          :            0.313078           -1.159568 %x8`fm  
Principal Planes      :            1.952094           -2.798584 a(DZGQ-as  
Anti-Principal Planes :           -1.325937            0.479447 DcR}pQ(e  
Nodal Planes          :            1.952094           -2.798584 -YjgS/g  
Anti-Nodal Planes     :           -1.325937            0.479447 4zfRD`;  
kxqc6  
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