B0: 3.0 mT
B1: 0 mT
B1 freq: 0.00 Hz

The CompassMR simulator can be used to explore and explain Magnetic Resonance (MR) underlying NMR and MRI. Drag objects or sliders to demonstrate MR, and proceed by using a coil for excitation and detection. Add spin when you understand the simpler Compass MR. Further advice is available in the CompassMR menu.

The CompassMR software (v. 3.2.0) illustrates Magnetic Resonance (MR) as used for MRI, NMR and ESR. You can explore Nuclear and Compass MR that are similar except for subatomic particles not only being magnetic, but also spinning. Click for YouTube demonstration. For advanced topics, try the Bloch Simulator.

The software creator Lars G. Hanson is a researcher at the DRCMR and the Technical University of Denmark. © 2015-2019, all rights reserved. Support is limited, but feedback appreciated (rate app, thanks).

Can you reinvent Magnetic Resonance? This phenomenon underlying NMR and MRI offers rare glimpses of the inner workings of cool objects such as molecules and living brains. Tissue is loaded with hydrogen nuclei that are slightly magnetic. These behave like compass needles that are initially aligned in a strong magnetic field, B0. If only you could find a practical way to detect needle oscillations without looking, and make the needles swing vigorously without touching.....

A free Android CompassMR app similar to this web version is available. It is useful when you want to understand MR or explain it to others. On other platforms, the "add to homescreen" functionality will give a similar experience.

Your feedback regarding current functionality will be useful, thanks. Please rate app, or send a mail with details about any experienced problem.