Optical measurements : high-speed imaging for the analysis of the
Optical measurements : !
high-speed imaging for the analysis of the!
dynamic behaviour of materials
Transparents du cours de M2 MAGIS, février 2011
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High-speed imaging on internet…
http://www.2fast4u.ipressl.at/
“Slow motion”…
What interest for mechanical engineering ?
(and in particular the study of dynamic behavior of materials…)
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1960-69 1970-79 1980-89 1990-99 2000-09
High-speed imaging for science !
In Experimental Mechanics (IF 1.469 (2008))
High-speed camera
(engineering) (materials)
High-speed photography
(engineering) (materials)
! One indicator :
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! See what cannot be seen…
The magic of high-speed imaging
Website Cordin
“High-speed photographic methods serve as
extension of our eye-sight” (Edgerton)
125’000 fps
1’000’000 fps
http://www.cordin.com/images.html
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The limitations of human sight
rods and cones
http://hyperphysics.phy-astr.gsu.edu/hbase/vision/rodcone.html
Rods : 120 millions (on retina),
Highly sensitive
in adapted conditions
B&W only
Cones : 7 millions (highest density
on macula),
Color perception
The eye -> perception of light intensity = light power x integration time
Persistence of vision : 50 ms
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