A camera body includes a movable main mirror for reflecting a light beam emerging from an objective lens, an optical element arranged along a reflection optical path of the movable main mirror and near a predetermined imaging plane of the objective lens, and having a plurality of micro refracting elements forming a display character, an eyepiece, a prism for deflecting the reflection optical path toward the eyepiece, and an illumination source, arranged in front of the prism, for causing the movable main mirror to reflect an illumination light beam to illuminate the display character.