如何分析Ghost focus generator的结果

Ghost Trace Data b^P\Q s*m  
File : C:\Program Files\ZEMAX - Beta\Samples\Sequential\Objectives\Cooke 40 degree field.zmx 3a=\$x@  
Title: A SIMPLE COOKE TRIPLET. crSqbL  
Units are Millimeters. bqx2lQf,_  
Wavelength: 0.550000 μm nQa:t. rC  
Type: Double Bounces }1lZW"{e[  
The '****' denotes a possible internal focus =Mxu,A  
RMS is the RMS spot radius on axis at the primary wavelength. !67xN?b  
RMS values of 0.00 indicate that an accurate RMS imhE=6{  
could not be computed, usually due to ray errors. P7l3ZH( g  
This analysis may be inaccurate if the system is (XFF}~>B.  
non-rotationally symmetric or uses non-standard surfaces. TgJ6O,0  
Ghost reflection off surface 2 then 1. (GH002001.ZMX) *O)i)["  
Surf     Marginal          F/#          RMS Pj{I}4P`  
   1  5.0000E+000     5.737068  3.5355E+000 P.1Z@HC  
   2  4.7160E+000     4.595701  3.3570E+000 e#F3KLSL`  
   1  4.3614E+000     0.990012  3.1277E+000 kVG+Wr7l0F  
   2  2.7155E+000     0.607262  1.9876E+000 '- #QK'p  
   3 -2.2309E+000     0.916280  2.6065E+000 s|TO9N)pO  
   4 -2.7766E+000     0.514753  0.0000E+000 n1PvZ~^3  
   5 -7.3909E+000     0.888038  0.0000E+000 nHp$5|r<  
   6 -9.0530E+000     0.823473  0.0000E+000 5 [4{1v  
   7 -3.4681E+001     0.823473  0.0000E+000 Dqd2e&a\  
Marginal ray height    :       -34.6809 8=?U7aw  
Chief ray height       :       -24.8107 t"e%'dFv  
Distance to ghost pupil:       -50.9613 kr!>rqN5  
Distance to ghost focus:       -57.1176 yF+mJ >kj  
Effective focal length :         8.2347