1. A medical apparatus, comprising: an illuminator that is capable of emitting a light for normal-light observation and a light for special-light observation to a living tissue for irradiation; an imager that picks up an image of a light from the living tissue irradiated with the light emitted from the illuminator; an image processor that generates a normal-light observation image obtained by picking up an image of a light from the living tissue irradiated with the light for normal-light observation in a first observation field of view in the imager, and further a special-light observation image obtained by picking up an image of a light from the living tissue irradiated with the light for special-light observation in a second observation field of view in the imager; a discriminator that determines matching of the first observation field of view and the second observation field of view; a processor that performs processing for displaying markers indicating the same position for the normal-light observation image and the special-light observation image when it is determined that the first observation field of view and the second observation field of view match each other in the discriminator, the processor performing processing for displaying the marker to be superimposed on each of the normal light observation image and the special-light observation image when it is determined that the first observation field of view and the second observation field of view match each other by the discriminator, and displaying the marker to be superimposed on one of the normal-light observation image and the special-light observation image when it is determined that the first observation field of view and the second observation field of view do not match each other by the discriminator; and a display that simultaneously displays the normal-light observation image and the special-light observation image processed in the processor.