US Patent 9720055 Magnetometer with light pipe

A device includes a diamond assembly. The diamond assembly includes a diamond with a plurality of nitrogen vacancy centers and electrical components that emit electromagnetic waves. The device also includes a light source configured to emit light toward the diamond and a photo detector configured to detect light from the light source that traveled through the diamond. The device further includes an attenuator between the diamond assembly and the photo detector. The attenuator is configured to attenuate the electromagnetic waves emitted from the electrical components of the diamond assembly.