Abstract: A belt device includes a belt member, a detected unit, a window, an optical detector, and a regulation member. The belt member is movable in a direction of belt movement. The detected unit disposed on at least one side of the belt in a width direction of the belt intersecting with the direction of belt movement and extending in the direction of belt movement. The window transmits detection light emitted toward the detected unit and reflected light from the detected unit. The optical detector detects the detected unit. The regulation member is disposed on at least one side in a width direction of the window to keep the detected unit away from the window.

Abstract: A belt device includes a belt member, a detected unit, a window, an optical detector, and a regulation member. The belt member is movable in a direction of belt movement. The detected unit disposed on at least one side of the belt in a width direction of the belt intersecting with the direction of belt movement and extending in the direction of belt movement. The window transmits detection light emitted toward the detected unit and reflected light from the detected unit. The optical detector detects the detected unit. The regulation member is disposed on at least one side in a width direction of the window to keep the detected unit away from the window.

Abstract: An optical scanner includes a light source to project light, a light deflector to deflect light, an optical element, and a holder to hold an optical element in place. The holder includes a curve adjustment mechanism, a first pressing member, a second pressing member, and a retainer. The curve adjustment mechanism adjusts a shape of the optical element in a sub-scanning direction relative to a scanning surface and perpendicular to a main scanning direction. The first pressing member is disposed at a first side from which the first pressing member presses the optical element in the sub-scanning direction. The second pressing member is disposed at a second side opposite the first side, to press the optical element from the second side. The retainer fixes substantially a center of the optical element in a main scanning direction of the light striking the optical element to the first side.

Abstract: An image forming apparatus includes a latent image carrier having a surface that moves, an optical writing unit that scans and emits light in a main scanning direction, a developing unit, a first storage unit, a second storage unit, and a control unit. The first storage unit stores first light intensity adjustment data for adjusting the intensity of light emitted from the optical writing unit such that the deviation of the emission intensity of the light in the main scanning direction due to characteristics of the optical writing unit is corrected. The second storage unit stores second light intensity adjustment data which can be set at each irradiation point in the main scanning direction and is for adjusting the intensity of the light emitted from the optical writing unit such that the deviation of image density at an arbitrary irradiation point in the main scanning direction is corrected.

Abstract: An optical scanner includes a light source to project light, a light deflector to deflect light, an optical element, and a holder to hold an optical element in place. The holder includes a curve adjustment mechanism, a first pressing member, a second pressing member, and a retainer. The curve adjustment mechanism adjusts a shape of the optical element in a sub-scanning direction relative to a scanning surface and perpendicular to a main scanning direction. The first pressing member is disposed at a first side from which the first pressing member presses the optical element in the sub-scanning direction. The second pressing member is disposed at a second side opposite the first side, to press the optical element from the second side. The retainer fixes substantially a center of the optical element in a main scanning direction of the light striking the optical element to the first side.

Abstract: An image forming apparatus includes a latent image carrier having a surface that moves, an optical writing unit that scans and emits light in a main scanning direction, a developing unit, a first storage unit, a second storage unit, and a control unit. The first storage unit stores first light intensity adjustment data for adjusting the intensity of light emitted from the optical writing unit such that the deviation of the emission intensity of the light in the main scanning direction due to characteristics of the optical writing unit is corrected. The second storage unit stores second light intensity adjustment data which can be set at each irradiation point in the main scanning direction and is for adjusting the intensity of the light emitted from the optical writing unit such that the deviation of image density at an arbitrary irradiation point in the main scanning direction is corrected.