[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？ 7o'kdYJzo  
一下是我的Prescription Data数据： nhiCV
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GENERAL LENS DATA: s-3vp  
k 32Jz.\B  
Surfaces                :                3 G%Wjtrpj  
Stop                    :                1 FJ}/g ?  
System Aperture         : Object Space NA = 0.12 z;2kKQZm  
Glass Catalogs          : Schott GbBcC#0  
Ray Aiming              : Paraxial Reference, Cache On q: ?6  
X Pupil shift          :               0 nH/V2>Lm  
Y Pupil shift          :               0 zxT&K|  
Z Pupil shift          :               0 D-69/3PvP  
Apodization             : Gaussian, factor =   1.00000E+000 [8l8m6  
************************************************************* ikw_t?  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) bX=A77  
Effective Focal Length  :        1.639158 (in image space) BJB'o  
************************************************************* @'7'3+ c  
Back Focal Length       :       -1.061568 (wo.OH  
Total Track             :           4.318 3l-8TR  
Image Space F/#         :        3.417255 6zaO$  
Paraxial Working F/#    :        2.950535 '>@evrG  
Working F/#             :        2.961912 ")i4w{_y  
Image Space NA          :       0.1670788 7??+8T#n*  
Object Space NA         :            0.12 >E^sZmY[f-  
Stop Radius             :       0.2398355 s1?N&t8c  
Paraxial Image Height   :               0 mXAX%M U  
Paraxial Magnification  :               0 PI)lJ\  
Entrance Pupil Diameter :       0.4796709 )8!""n~  
Entrance Pupil Position :               0 K\,)9:`t  
Exit Pupil Diameter     :        2.511155 _RST[B.u6  
Exit Pupil Position     :        7.420935 69p>?zn  
Field Type              : Angle in degrees VK[^v;  
Maximum Field           :               0 [K9l>O  
Primary Wave            :            1.31 `!K(P- yB?  
Lens Units              :   Millimeters l*e*jA_>:7  
Angular Magnification   :               0 jL<:N 8  
)4toBDg"  
Fields          : 1 wJNiw)C  
Field Type: Angle in degrees 9!NL<}]{  
#        X-Value        Y-Value         Weight [h {zT)[  
1       0.000000       0.000000       1.000000 ~+/IzckrG  
9l]+rs+  
Vignetting Factors 0L S,(v4  
#       VDX       VDY       VCX       VCY       VAN -B*= V  
1  0.000000  0.000000  0.000000  0.000000  0.000000 &'
TZU"_  
^mv F%"g  
Wavelengths     : 1 '-N `u$3Y  
Units: Microns zn@<>o8hU  
#          Value         Weight O&RW[ml*3  
1       1.310000       1.000000 Pv|g.hH9m  
{P&{+`sov  
CARDINAL POINTS:
@@-n/9>vs  
"jb`KBH%"  
Object space positions are measured with respect to surface 1. TWZ**S-  
Image space positions are measured with respect to the image surface. "v@Y[QI  
The index in both the object space and image space is considered. EZ:pcnL{  
m(i84~  
                          Object Space         Image Space 1hp`.!3]H  
W = 1.310000 (Primary) 2!Yq9,`  
************************************************************ @tGju\E"o  
Focal Length          :           -1.639015            1.639015 WYSqnmi  
************************************************************ MKf|(6;~  
Focal Planes          :            0.313078           -1.159568 O2g9<H  
Principal Planes      :            1.952094           -2.798584 Z-z^0QO  
Anti-Principal Planes :           -1.325937            0.479447 @a$_F3W  
Nodal Planes          :            1.952094           -2.798584 ,R#pQ 4  
Anti-Nodal Planes     :           -1.325937            0.479447 YcOPqvQ  
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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