A lighting device includes a light source, a light guide, a light guide cover, and a unit frame. The light guide is in a bar form and, while guiding light that has entered from the light source along the axial direction, sends forth the light. The light guide cover holds the light guide. The light guide cover is attached to a unit frame. The light guide cover includes a main body portion and a plurality of light guide holding portions provided along the longitudinal direction of the main body portion and holding the light guide at a plurality of places, and a plurality of guide engaging portions provided along the longitudinal direction of the main body portion. The unit frame has a cover fitting face to which the light guide cover is fitted and a plurality of cover guides with which a plurality of guide engaging portions engage respectively.

A lighting device includes a light source, a light guide, a light guide cover, and a unit frame. The light guide is in a bar form and, while guiding light that has entered from the light source along the axial direction, sends forth the light. The light guide cover holds the light guide. The light guide cover is attached to a unit frame. The light guide cover includes a main body portion and a plurality of light guide holding portions provided along the longitudinal direction of the main body portion and holding the light guide at a plurality of places, and a plurality of guide engaging portions provided along the longitudinal direction of the main body portion. The unit frame has a cover fitting face to which the light guide cover is fitted and a plurality of cover guides with which a plurality of guide engaging portions engage respectively.

An image forming apparatus includes first and second image forming portions, a power source portion, and a controller. The power source portion is constituted so that when the power source portion applies a charging voltage to a first charging member of the first image forming portion, the charging voltage is also applied to a second charging member of the second image forming portion. The controller carries out control so that a timing of a start of discharge of the first photosensitive drum in the first image forming portion is made earlier than a timing of a start of image formation by the first image forming portion and so that a timing of a start of discharge of the second photosensitive drum in the second image forming portion is made earlier than a timing of a start of image formation by the second image forming portion.

An image forming apparatus includes a first image forming portion, a second image forming portion, a power source portion, and a controller. The power source portion is constituted so that when the power source portion applies a charging voltage to a first charging member of the first image forming portion, the charging voltage is also applied to a second charging member of the second image forming portion. The controller carries out control so that an emitted light quantity of a light emitting element is changed from a first light quantity to a second light quantity larger than the first light quantity and is changed from the second light quantity to a third light quantity larger than the second light quantity.

A light guide device includes: a housing main body; a side member attached to a side portion in the housing main body; a light guide body supported by the housing main body and including a light incident surface to which light enters; a light source substrate held by the side member and including a light element that emits the light toward the light incident surface; and a positioning portion configured to position the light element to a reference position with respect to the light incident surface. The positioning portion includes: an abutting member provided in the housing main body and configured to abut on a mounting surface in the light source substrate on which the light element is mounted; and an elastic member held by the side member and configured to press the light source substrate toward the light guide body to position the light element to the reference position.

An image forming apparatus includes: a photosensitive drum; a light guide plate that irradiates, onto the photosensitive drum, light incoming through an end thereof by emitting the light from an irradiation end surface thereof; a static elimination light source that is disposed near the end of the light guide plate and emits the light into the light guide plate; and a blocking wall that is disposed between the light guide plate and the photosensitive drum to cover the irradiation end surface, and restricts the light emitted from the irradiation end surface non-uniformly in a longitudinal direction of the light guide plate. Of the light emitted from the irradiation end surface, portions emitted from end regions located around ends of the light guide plate are less restricted by the blocking wall than a portion emitted from a region other than the end regions of the light guide plate.

An image forming apparatus includes: a photosensitive drum; a light guide plate that irradiates, onto the photosensitive drum, light incoming through an end thereof by emitting the light from an irradiation end surface thereof; a static elimination light source that is disposed near the end of the light guide plate and emits the light into the light guide plate; and a blocking wall that is disposed between the light guide plate and the photosensitive drum to cover the irradiation end surface, and restricts the light emitted from the irradiation end surface non-uniformly in a longitudinal direction of the light guide plate. Of the light emitted from the irradiation end surface, portions emitted from end regions located around ends of the light guide plate are less restricted by the blocking wall than a portion emitted from a region other than the end regions of the light guide plate.

An image forming apparatus includes a photoconductor, a charger, a charge remover, and control circuitry. The charger is configured to charge the photoconductor. The charge remover is configured to remove charge from a surface of the photoconductor by light and electric discharge. The control circuitry is configured to: estimate a surface potential that the photoconductor has after the photoconductor is charged by the charger, based on a characteristic value of the photoconductor and a value of a current flowing through the charger after the charge remover removes charge from the photoconductor; and control a charging bias applied to the charger, based on the surface potential estimated.

In an image forming apparatus having a housing; a cartridge including an image bearing member and capable of being attached/detached to/from the housing; a discharging exposure unit having a light source member and a light guide member, which forms a light guide path guiding light from the light source member so as to be emitted to the image bearing member, and exposing the image bearing member; and an opening/closing member capable of being opened/closed and provided on a surface on which an opening portion, through which the cartridge is inserted/removed in the housing, is provided so as to cover the opening portion, wherein the light source member is provided so as to be exposed to a surface of the housing opened/closed by the opening/closing member and be capable of being attached/detached to/from the light guide member.

In an image forming apparatus having a housing; a cartridge including an image bearing member and capable of being attached/detached to/from the housing; a discharging exposure unit having a light source member and a light guide member, which forms a light guide path guiding light from the light source member so as to be emitted to the image bearing member, and exposing the image bearing member; and an opening/closing member capable of being opened/closed and provided on a surface on which an opening portion, through which the cartridge is inserted/removed in the housing, is provided so as to cover the opening portion, wherein the light source member is provided so as to be exposed to a surface of the housing opened/closed by the opening/closing member and be capable of being attached/detached to/from the light guide member.