Motion Measurements With Three Degrees Of Freedom
Images of a moving structure taken at a single plane of focus provide
information about three independent degrees of freedom of motion:
displacement in the x and y directions (within the plane of focus), and
rotation within this plane.
This image shows the displacement of a MEMS device moving in response to a
The primary component of motion is in the y direction (up-and-down on the
screen), and is roughly 400 nanometers peak-to-peak.
Motion in the x direction (left-and-right) is below the noise floor of the
Rotation of the device within the plane of focus is also below the noise