Although 2 RVR device symbols are given in the airport planview, it is written in the takeoff minimums section that all 3 RVR values (TDZ, Mid, Rollout) must be provided for the departure limits. MID RVR is not provided in planview. Is it because it is forgotten or is it because the RVR devices we call TDZ, MID, RO have different meanings? Or can a single transmissometer measure the RVR value in all areas (TDZ, MID, RO)? I couldn't understand the situation.