如何分析Ghost focus generator的结果

Ghost Trace Data #^_7i)=~  
File : C:\Program Files\ZEMAX - Beta\Samples\Sequential\Objectives\Cooke 40 degree field.zmx cpH*!*S
 
Title: A SIMPLE COOKE TRIPLET. RDeI l&  
Units are Millimeters. rcf#8  
Wavelength: 0.550000 μm Va4AE)[/*  
Type: Double Bounces ?'>[
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The '****' denotes a possible internal focus V0bKtg1f?-  
RMS is the RMS spot radius on axis at the primary wavelength. 2h)*  
RMS values of 0.00 indicate that an accurate RMS {M23a _t\  
could not be computed, usually due to ray errors. A&d_!u>  
This analysis may be inaccurate if the system is uZP(-}  
non-rotationally symmetric or uses non-standard surfaces. Wt=%.Y(x  
Ghost reflection off surface 2 then 1. (GH002001.ZMX) <^+&A7Q-_  
Surf     Marginal          F/#          RMS rm<`H(cT  
   1  5.0000E+000     5.737068  3.5355E+000 sDwE,f0h  
   2  4.7160E+000     4.595701  3.3570E+000 ;`
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   1  4.3614E+000     0.990012  3.1277E+000 e63io0g>  
   2  2.7155E+000     0.607262  1.9876E+000 R_IT${O  
   3 -2.2309E+000     0.916280  2.6065E+000 G&yF9s)Lvs  
   4 -2.7766E+000     0.514753  0.0000E+000 j[=P3Z0q  
   5 -7.3909E+000     0.888038  0.0000E+000 ^
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   6 -9.0530E+000     0.823473  0.0000E+000 '<wZe.Q!  
   7 -3.4681E+001     0.823473  0.0000E+000 Ut(BQM>U+$  
Marginal ray height    :       -34.6809 Zf?jnDA  
Chief ray height       :       -24.8107 ?aZ\Dg{  
Distance to ghost pupil:       -50.9613 3ZAzv en  
Distance to ghost focus:       -57.1176 6a6N$v"  
Effective focal length :         8.2347