Patent ID: 7937003

Claim:
An image forming apparatus comprising: a photosensitive element; a charging unit that charges the photosensitive element; an exposing unit that irradiates light onto a surface of the photosensitive element charged by the charging unit to expose the surface of the photosensitive element and forms an electrostatic latent image on the surface of the photosensitive element; a developing unit that allows a developer having a charging property to be adhered to a development member that comes into contact with the surface of the photosensitive element, and applies to the development member a development bias to form, between the development member and the surface of the photosensitive element, an electric field in a direction in which the developer is adhered to the electrostatic latent image, whereby the developer is adhered to the electrostatic latent image and the electrostatic latent image is developed as a developer image; a transferring unit that transfers the developer image onto a recording medium and forms an image on the recording medium; an exposure instructing unit that allows the exposing unit to perform exposure on the surface of the charged photosensitive element at a specified density which is specified in advance; a measuring unit that measures a magnitude of a current that flows between the photosensitive element and the development member; a degradation determining unit that determines that a charging property of the developer is degraded when a value measured by the measuring unit is less than a first threshold which is set in advance; and a remaining amount shortage determining unit that determines that an amount of remaining developer is short when the value measured by the measuring unit is less than a second threshold, the second threshold being set in advance and being smaller than the first threshold.