I've looked at this method before for a single level reading, but a problem
arose in that the fluid(water) was dirty and contained some oil which coated
the reflective face and therefore can a false reading. My conclusion was
that this method would only work with a clean fluid.
John
***************************************************************
John.Walshe@inpactmicro.com

INPACT MICROELECTRONICS (Irl) Ltd
21A Pouladuff Road,
Cork,
Ireland,

Tel: +353 21 4318296
Fax: +353 21 4318980

WWW.INPACTMICRO.COM
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