An inserting state acquiring section (51) acquires inserting state information of an inserting section that is to be inserted into an insertion subject, and an insertion subject shape acquiring section (52) acquires shape information of the insertion subject. A positional relation calculating section (54) is input the inserting state information and the insertion subject shape information and calculates a positional relation of the inserting section to the insertion subject, and an output section (55) outputs the calculation result of the positional relation calculating section (54) as display information.
