Celebrate Princeton Invention: Craig Arnold Posted December 21,
2009; 01:08 p.m. Able to adjust its focus more than 100,000
times faster than the human eye, the TAG Lens invented by
mechanical and aerospace engineering professor Craig Arnold and
his colleagues has applications in materials processing and
imaging. (Photo: Brian Wilson) Name: Craig Arnold, associate
professor of mechanical and aerospace engineering Invention:
Tunable Acoustic Gradient Index of Refraction Lens (TAG Lens)
What it does: The TAG lens features a cylinder made of a special
material that vibrates when electricity is passed through it,
enclosed inside a fluid-filled chamber. Controlling the flow of
electricity changes the vibrations that propagate through the
fluid, changing the lens' focus more than 100,000 times faster
than the human eye can refocus. Inspiration: After developing a
low-cost lens to shape laser beam output into different
patterns, Arnold and his colleagues focused their attention on
understanding how the device worked