[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？ IP ,.+:i  
一下是我的Prescription Data数据： P
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GENERAL LENS DATA: #!})3_Qc(y  
]-:6T0JuS  
Surfaces                :                3 w"8V0z  
Stop                    :                1 \uM? S  
System Aperture         : Object Space NA = 0.12 pOA!#Aj)  
Glass Catalogs          : Schott ,mKObMu  
Ray Aiming              : Paraxial Reference, Cache On g^l RG3a  
X Pupil shift          :               0 uel{`T[S  
Y Pupil shift          :               0 2*2:-ocl$  
Z Pupil shift          :               0 {^m
Kvc  
Apodization             : Gaussian, factor =   1.00000E+000 rN5tI.iC  
************************************************************* 66\jV6eH7L  
Effective Focal Length  :        1.639158 (in air at system temperature and pressure) K_ke2{4Jm  
Effective Focal Length  :        1.639158 (in image space) h@1!T  
************************************************************* !SxG(*u  
Back Focal Length       :       -1.061568
Vh
Eka#  
Total Track             :           4.318 57Z-  
Image Space F/#         :        3.417255 , ZFE(  
Paraxial Working F/#    :        2.950535 _#C()Ro*P  
Working F/#             :        2.961912 wtH~-xSB|  
Image Space NA          :       0.1670788 3BQ!qO17^d  
Object Space NA         :            0.12 ig+4S[L~n  
Stop Radius             :       0.2398355 1^G{tlA-  
Paraxial Image Height   :               0 T!|=El>  
Paraxial Magnification  :               0 Z?G&.# :  
Entrance Pupil Diameter :       0.4796709 GJA`l8`SQ  
Entrance Pupil Position :               0 ",Cr,;]  
Exit Pupil Diameter     :        2.511155 bt/ =Kq#  
Exit Pupil Position     :        7.420935
@n+=vC.xO  
Field Type              : Angle in degrees z-T{~{q  
Maximum Field           :               0 Jkt4@h2Q}  
Primary Wave            :            1.31 Y.6SOu5$]  
Lens Units              :   Millimeters {XCf-{a]~  
Angular Magnification   :               0 gVR@&bi7  
WyhhCR=;  
Fields          : 1 (eWPis[  
Field Type: Angle in degrees >QkP7Kb  
#        X-Value        Y-Value         Weight Zu*K-ep"  
1       0.000000       0.000000       1.000000 5Wx~ZQZ  
0Q5^C!K  
Vignetting Factors  |a^U]  
#       VDX       VDY       VCX       VCY       VAN /8'S1!zc  
1  0.000000  0.000000  0.000000  0.000000  0.000000 2}U!:bn(  
"tk-w{>  
Wavelengths     : 1 5*g]qJF  
Units: Microns ,E )|y4  
#          Value         Weight (qMj-l  
1       1.310000       1.000000 Fg]?zEa  
~wm;;#_O  
CARDINAL POINTS: )FN;+"IJ  
z
muMWT;  
Object space positions are measured with respect to surface 1. V N{NA+I  
Image space positions are measured with respect to the image surface. _f0C Y"  
The index in both the object space and image space is considered. _*M42<wcO  
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                          Object Space         Image Space VSX@e|Nj  
W = 1.310000 (Primary) yM.IxpT#$  
************************************************************ PQmq5N6  
Focal Length          :           -1.639015            1.639015 #FOqP!p.E  
************************************************************ {@Yb%{+  
Focal Planes          :            0.313078           -1.159568 3\O|ii  
Principal Planes      :            1.952094           -2.798584 Rgy-OA  
Anti-Principal Planes :           -1.325937            0.479447 T VmH  
Nodal Planes          :            1.952094           -2.798584 M,5j5<7  
Anti-Nodal Planes     :           -1.325937            0.479447 @Hb'8F  
,fDEz9-,  
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