A charging roller is provided. The charging roller is configured to face
an image carrier at a predetermined charging gap and charge the image
carrier in a non-contact state. A conductive shaft is provided with a
pair of annular concave portions formed on an outer circumferential
surface at both ends thereof. A conductive layer is formed on the outer
circumference surface at a center portion of the conductive shaft defined
between the pair of concave portions. An insulating layer is formed on
the outer circumferential surface at outer portions of the conductive
shaft from the pair of annular concave portions. A depth of the concave
portions is larger than a thickness of the conductive layer.