Micro Motor Technology
The Micro Motor (MM) has a diameter of only 1mm. It functions as a two phase synchronous motor with 4 coils and a 2 pole magnet. The rotational speed follows the frequency of the supplied current and because of its very small inertia, the Micro Motor can reach a speed of 200,000 rpm.
Micro Motors are used in OCT intravascular imaging. The Micro Motor is placed at the catheter tip. It rotates a small mirror that deflects the laser beam sidewards and makes a cross-sectional image of an artery. This is explained in the Voice of America item published on 1 april 2015:
A micro-motor paper, titled ” Development of a high-speed synchronous micro motor and its application in intravascular imaging”, is published by Sensors and actuators A: Physical.