What actually happens inside the rotary Electric Encoder?
An internally generated space/time modulated electric field interacts with a rotor which is made of a dielectric composite material. The rotor includes a peripheral sinusoidally shaped 3D pattern that serves the fine channel, and a recessed sinusoidal pattern that serves the coarse channel. The electric field is integrated over the full rotor area (hence holistic ) and the resulting signal is processed and separated into Sine and Cosine output channels. Since a common channel processes both the Sine and Cosine outputs they are nearly matched and the decoded angle is stable over time and temperature.
