[Raytrace] Dall Null

[John D. Upton]

Tom,

At 08:39 PM 9/4/2002 -0700, you wrote:
>I also got 1/10 wave - RMS - not P-V.  I  got 0.15 P-V with the nulling
>lens on axis, no mask. Does this agree with your result? I understood
>everything in your data but the PY 0.0 - what is that? Tom W.

     No, the file I posted shows me a 0.110 wave PV and 0.037 wave RMS on 
the wavefront.  Copy the text of the file I posted into a *.len file on 
your system and open it up.  See what it says when you run an "spd" 
command.  There may be something odd going on here.  I have sometimes 
confused OSLO-LT enough that it gives obviously "left field" results until 
I re-enter all the data.

     Has anyone else built a model based on Tom's description and gotten 
something different?  Here is the text prescription I used:

22 Inch F:4.5 Dall Null tilt 0.5
  SRF      RADIUS      THICKNESS   APERTURE RADIUS       GLASS  SPE  NOTE
  OBJ       --        157.841870 V    0.000158             AIR
  AST   156.402902      4.000000     18.013877 AS          BK7 C
   2        --        4.7843e+03     18.157875 S           AIR
   3   -5.0292e+03   -4.9445e+03 S  279.400000 SX   REFL_HATCH   *
  IMS       --         -0.529301      0.030227 S

*CONIC AND POLYNOMIAL ASPHERIC DATA
  SRF        CC          AD          AE          AF          AG
   3      -1.000000      --          --          --          --

*TILT/DECENTER DATA
   3     DT    1         DCX       --       DCY       --       DCZ       --
                         TLA     0.500000   TLB       --       TLC       --


Sincerely,

John D. Upton
Georgetown, TX
<http://www.atm-workshop.com/>      "The ATM's Workshop Page"
<http://hometown.aol.com/RonWin20/>  "Ronchi For Windows Software Page"