A controller which causes a light emitting element to continuously perform minute emission for a plurality of dots in a level in which toner is not attached to a non-image section on an image bearing member is provided. The controller controls a first driving current for an image section and controls a second driving current used to perform the minute emission by the light emitting element in the non-image section several times in one job. In the image section, a driving current obtained by adding the first driving current to the second driving current is supplied so that the light emitting element emits light.

At least one partial measurement region is set in the longitudinal direction in a printable region of a photosensitive drum 3. After the photosensitive drum 3 has been charged to a constant potential with a charging roller 6, different potentials are set in the partial measurement region and a region excluding partial measurement region with a laser scanner 4, partial discharge information of the partial measurement region is detected by discharge information detection unit, and a bias voltage in image formation that is applied to the charging roller 6 is corrected on the basis of the value of the partial discharge information.

A discharging method used in an image forming apparatus includes discharging, with an exposure device, an exposure range of the latent image bearer, and discharging, with a discharger, an area of the latent image bearer outside the exposure range and inside a developing range in a main scanning direction. The exposure range is inside the developing range in the main scanning direction. The discharging with the exposure device and the discharging with the discharger are performed when a rotation of the latent image bearer is stopped after a toner image is transferred from the latent image bearer.

A discharging light quantity adjusting device includes a potential measurement controller that performs: a process of causing a first toner image forming process to charge an image holding member to a first potential and an electrometer to measure an electrostatic potential on the image holding member to obtain a first value, a process of causing a second toner image forming process to charge the image holding member to a second potential and removing a toner image formed by the second toner image forming process, and a process of causing a third toner image forming process to charge the image holding member to a third potential, and causing the electrometer to measure an electrostatic potential on the image holding member to obtain a second value; and a light quantity adjusting unit that adjusts a quantity of a discharging light based on the first and second values.

A controller which causes a light emitting element to continuously perform minute emission for a plurality of dots in a level in which toner is not attached to a non-image section on an image bearing member is provided. The controller controls a first driving current for an image section and controls a second driving current used to perform the minute emission by the light emitting element in the non-image section several times in one job. In the image section, a driving current obtained by adding the first driving current to the second driving current is supplied so that the light emitting element emits light.

A controller which causes a light emitting element to continuously perform minute emission for a plurality of dots in a level in which toner is not attached to a non-image section on an image bearing member is provided. The controller controls a first driving current for an image section and controls a second driving current used to perform the minute emission by the light emitting element in the non-image section several times in one job. In the image section, a driving current obtained by adding the first driving current to the second driving current is supplied so that the light emitting element emits light.

An image forming apparatus includes an image bearing member, a charging member, an exposure unit which performs first exposure to form a non-image portion potential on the electrically charged surface of the image bearing member, and second exposure to form an image portion potential thereon, a developing member, a charging voltage application unit, a current detection unit which detects a current flowing from the image bearing member to the charging member, and a control unit which controls the exposure unit and the charging voltage application unit, wherein, in a case where a current value detected in a predetermined charging voltage application state is a second current value larger than a first current value, the control unit controls the exposure unit to perform image formation with a first exposure amount smaller than that in a case where the detected current value is the first current value.

An image forming apparatus includes an image bearing member, a charging member, an exposure unit which performs first exposure to form a non-image portion potential on the electrically charged surface of the image bearing member, and second exposure to form an image portion potential thereon, a developing member, a charging voltage application unit, a current detection unit which detects a current flowing from the image bearing member to the charging member, and a control unit which controls the exposure unit and the charging voltage application unit, wherein, in a case where a current value detected in a predetermined charging voltage application state is a second current value larger than a first current value, the control unit controls the exposure unit to perform image formation with a first exposure amount smaller than that in a case where the detected current value is the first current value.

An image forming apparatus includes: an image bearing member to rotate; a charging member to charge a surface of the image bearing member; a charging voltage applying portion to apply an alternating-current voltage having a predetermined charging frequency to the charging member; and an exposing portion to perform image exposure and background exposure. A plurality of modes are settable for the image forming apparatus, and the plurality of image forming modes include image forming modes different in a background potential difference which is a potential difference between a surface potential of the image bearing member after the surface of the image bearing member is charged and before the charged surface is exposed by the exposing portion and a surface potential of a portion of the surface of the image bearing member which has been subjected to the background exposure.

An image forming apparatus includes: an image bearing member to rotate; a charging member to charge a surface of the image bearing member; a charging voltage applying portion to apply an alternating-current voltage having a predetermined charging frequency to the charging member; and an exposing portion to perform image exposure and background exposure. A plurality of modes are settable for the image forming apparatus, and the plurality of image forming modes include image forming modes different in a background potential difference which is a potential difference between a surface potential of the image bearing member after the surface of the image bearing member is charged and before the charged surface is exposed by the exposing portion and a surface potential of a portion of the surface of the image bearing member which has been subjected to the background exposure.