Abstract: An image forming device comprises: an exposer having a plurality of light emitting devices, a light emitting device among the plurality of light emitting devices to transmit light toward a photosensitive drum; and a developer to develop an electrostatic latent image formed on a surface of the photosensitive drum by the light, wherein the light emitting device among the plurality of light emitting devices includes: a light emitting layer to generate the light; and a reflective layer to reflect at least a portion of the generated light. The reflective layer can include a plurality of sub-reflective layers, in which a thickness of a sub-reflective layer among the plurality of sub-reflective layers is different from a thickness of another sub-reflective layer among the plurality of sub-reflective layers, and/or a refractive index of a sub-reflective layer among the plurality of sub-reflective layers is different from a refractive index of another sub-reflective layer among the plurality of sub-reflective layers.

Abstract: An image forming device comprises: an exposer having a plurality of light emitting devices, a light emitting device among the plurality of light emitting devices to transmit light toward a photosensitive drum; and a developer to develop an electrostatic latent image formed on a surface of the photosensitive drum by the light, wherein the light emitting device among the plurality of light emitting devices includes: a light emitting layer to generate the light; and a reflective layer to reflect at least a portion of the generated light. The reflective layer can include a plurality of sub-reflective layers, in which a thickness of a sub-reflective layer among the plurality of sub-reflective layers is different from a thickness of another sub-reflective layer among the plurality of sub-reflective layers, and/or a refractive index of a sub-reflective layer among the plurality of sub-reflective layers is different from a refractive index of another sub-reflective layer among the plurality of sub-reflective layers.

Abstract: A light-emitting element array module includes a control driver configured to receive print data and operate, and light-emitting element array chips configured to receive a signal from the control driver, respectively, and operate, wherein the light-emitting element array chips are connected to the control driver through respective data lines, and the control driver controls an operation point in time of each of the light-emitting element array chips by adjusting input points in time of a start signal and a data signal according to a registration error of each of the light-emitting element array chips.

Abstract: A luminous flux limit device, an optical scanning unit employing the luminous flux limit device, and an electrophotographic image forming apparatus are provided. The luminous flux limit device limits a luminous flux of the optical scanning unit and includes a light-blocking portion, a light transmissive region around the light blocking region, and a light blocking outer region around the light transmissive region.

Abstract: A light-emitting element array module includes a control driver configured to receive print data and operate, and light-emitting element array chips configured to receive a signal from the control driver, respectively, and operate, wherein the light-emitting element array chips are connected to the control driver through respective data lines, and the control driver controls an operation point in time of each of the light-emitting element array chips by adjusting input points in time of a start signal and a data signal according to a registration error of each of the light-emitting element array chips.

Abstract: A luminous flux limit device, an optical scanning unit employing the luminous flux limit device, and an electrophotographic image forming apparatus are provided. The luminous flux limit device is a device that limits a luminous flux of the optical scanning unit and includes a body portion with an aperture and a light-blocking portion that prevents light from being transmitted via a portion of the aperture. The aperture includes a blocking region in which light is blocked by the light-blocking unit, and a transmissive region that is a remaining region of the aperture excluding the blocking region.

Abstract: A light scanning unit and an electrophotographic image forming apparatus are provided. The light scanning unit includes a light source emitting the light beams according to an image signal, an incident optical system including a flux-limiting element limiting the flux of light beams emitted by the light source, an optical deflector deflecting the light beams emitted by the light source in a main scanning direction, and an image forming optical system including a scanning optical element imaging the light beams deflected by the optical deflector on a scanning target surface, the light scanning unit forming an electrostatic latent image by scanning the light beams to the scanning target surface of the image bearing member. The scanning optical element of the scanning optical elements of the image forming optical system is eccentrically arranged from a central optical axis of the image forming optical system in a sub-scanning direction.

Abstract: A lens array, a linear light exposure device, and an optical apparatus including the linear light exposure device. The lens array includes: an image side lens array unit in which a plurality of lens cells are arranged in at least one line along an arrangement direction to have optical axes parallel with each other; and a light blocking unit provided on an incidence surface of the image side lens array unit, the light blocking unit having light transmission regions, through which light is transmitted toward each lens cell, and blocking regions in regions other than the light transmission regions, wherein each lens cell of the image side lens array unit has a square formed effective optical region.

Abstract: A light scanning unit and an electrophotographic image forming apparatus are provided. The light scanning unit includes a light source emitting the light beams according to an image signal, an incident optical system including a flux-limiting element limiting the flux of light beams emitted by the light source, an optical deflector deflecting the light beams emitted by the light source in a main scanning direction, and an image forming optical system including a scanning optical element imaging the light beams deflected by the optical deflector on a scanning target surface, the light scanning unit forming an electrostatic latent image by scanning the light beams to the scanning target surface of the image bearing member. The scanning optical element of the scanning optical elements of the image forming optical system is eccentrically arranged from a central optical axis of the image forming optical system in a sub-scanning direction.

Abstract: A lens array, a linear light exposure device, and an optical apparatus including the linear light exposure device. The lens array includes: an image side lens array unit in which a plurality of lens cells are arranged in at least one line along an arrangement direction to have optical axes parallel with each other; and a light blocking unit provided on an incidence surface of the image side lens array unit, the light blocking unit having light transmission regions, through which light is transmitted toward each lens cell, and blocking regions in regions other than the light transmission regions, wherein each lens cell of the image side lens array unit has a square formed effective optical region.