Abhay,
If you support your diaphragm on a ring and either apply pressure or vacuum
- real slight - on it, it will curve. If you observe it under florescent
lights with a rectangular grid, you will notice the distortion of the grid
reflection on you diaphragm. The center is the symmetrical cent of the
distortion

Shay

-----Original Message-----
From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org]
On Behalf Of Abhay C. Deshpande _04307411_
Sent: Tuesday, October 25, 2005 6:14 AM
To: mems-talk@memsnet.org
Subject: [mems-talk] testing of a diaphragm

hello everyone,
  i have made a diaphragm by using single polished wafer. i need to test the
diaphragm. i want to test the diaphragm by applying point load at the center
from the front side. please advice me on how to pinpoint the center of the
diaphragm for applying the load.

thanks and regards
abhay