The concept of the MCAO upgrade for the Daniel K. Inouye Solar Telescope

The 4-meter Daniel K. Inouye Solar Telescope shall be upgraded with a mirror multi-conjugate adaptive optics system a few years after first light, replacing its initial high-order single conjugate system. We present the technical concept of this system and its subsystems. The system design sports three deformable mirrors, nine correlating Shack-Hartmann wavefront sensors, and a computer cluster for the control loop. We discuss the demands and challenges as well as our plans to implement the wavefront sensing and control systems.