From: Michael E. Viola
Sent: Wednesday, November 01, 2006 2:25 PM
To: Lawrence E. Dudek; Steve Raftopoulos; Michael J. Duco
Cc: John W. Edwards; Wayne T. Reiersen; Thomas G. Brown; Ronald L.
Strykowsky
Subject: Leica support

Larry, Steve, Mike
 
We are experiencing "noise" in the metrology system again.
I called Leica Don Demetrakaes, his rates are $125/hr plus expenses.
He is available the first week of December.
 
EMSCON allows Verisurf (third party software) to trigger the controller to take the measurements.  It also includes a web based program that allows you to take measurements in EMSCON and therefore eliminate the Verisurf software as a potential source of a problem.  EMSCON must be used by third party software to properly access the Leica head.  Any other method i.e. NETBUI is considered a kluge by Leica and is not reliable nor supported.  
Therefore we must purchase EMSCON now to continue with reliable Verisurf operation.
 
Regarding measurement accuracy:
The Birdbath does nothing for us in continuous mode and should not be a gage for stability. In fact the birdbath position causes the head motors to hunt vigorously while reading in continuous mode. It would be better to put a nest out 6 feet and use that.
There are three checks for stability and accuracy:
1) 2 face field check sites on a target rotates the head rereads the head. (angle encoder check daily 3 minutes)
2) Interferometer (IFM) check    (
3) ADM check                          (weekly 20 minute total)
 
I am directing Mike Duco to perform the field checks per the above schedule.
 
In continuous mode the redundancy of measurements is not real.
The tech spec is +/-0.001" in 10' envelope plus 10 microns (0.0004")/meter beyond that.
 
Rental is at the rate of 10% of the overall cost with a minimum time of 2 weeks.
The system the we would need is the 840 and would run around $300K so the rental rate is ~$30K/month

 

Thanks,

Mike Viola, PPPL, (609) 243 3655