In a message dated 12/05/2010, gmvoeth@........... writes:

Back to  the light thingy, Given A Mass and Spring: It Seems To Me You 
might get X1000  magnification of motion by putting a light source with a small 
radius fixed to  a stationary location connected to the mass and then like 
50 to 100 feet more  away sensing the lights motion.

Have you ever seen such a mechanically  amplified sensor before ?



Hi Geoff,
 
    This is called an optical lever and it was used on  pre-electronic 
seismic sensors with mirror galvanometers, recording on photo  sensitive paper. 
The seismometer used a magnet + coil detector to drive the  galvanometer 
coil. You had to wet develop, fix and dry the paper before it could  be read. 
You are unlikely to get enough light intensity to use large  separations with 
electronic detectors. If you want to see what you can observe,  try using 
one of the red pen lasers. It was also used directly with a mirror on  the 
Wood-Anderson short period seisometers. See 
_http://www.eas.slu.edu/Earthquake_Center/Instruments/_ 
(http://www.eas.slu.edu/Earthquake_Center/Instruments/) 
 
    Regards,
 
    Chris Chapman
 
    






In a message dated 12/05/2010, gmvoeth@........... writes:
Back to=20
  the light thingy, Given A Mass and Spring: It Seems To Me You might get=
 X1000=20
  magnification of motion by putting a light source with a small radius fi=
xed to=20
  a stationary location connected to the mass and then like 50 to 100 feet=
 more=20
  away sensing the lights motion.

Have you ever seen such a mechani=
cally=20
  amplified sensor before ?


Hi Geoff,
 
    This is called an optical lever and it was us=
ed on=20
pre-electronic seismic sensors with mirror galvanometers, recording on pho=
to=20
sensitive paper. The seismometer used a magnet + coil detector to drive th=
e=20
galvanometer coil. You had to wet develop, fix and dry the paper before it=
 could=20
be read. You are unlikely to get enough light intensity to use large=
=20
separations with electronic detectors. If you want to see what you can obs=
erve,=20
try using one of the red pen lasers. It was also used directly with a mirr=
or on=20
the Wood-Anderson short period seisometers. See http://www.eas.slu.edu/Earthquake=
_Center/Instruments/
 
    Regards,
 
    Chris Chapman