A lens unit according to an embodiment includes: a lens array that includes lens elements each provided with an optical axis and extends in a first direction; a support member that supports the lens array; and an adhesive that bonds the lens array and the support member. The support member includes a first adhesive holding portion with a specified depth in a direction of the optical axis and a second adhesive holding portion shallower than the first adhesive holding portion. The first adhesive holding portion and the second adhesive holding portion are aligned in the first direction. The adhesive is arranged at the first adhesive holding portion and the second adhesive holding portion.

An image forming apparatus includes: a photoreceptor; a light source; a rotational polygon mirror including a plurality of mirror surfaces on an outer circumferential surface of a rotating body; and a hardware processor that: controls the light source to perform emission of a light beam; controls to rotate the rotational polygon mirror to perform a sequential primary scanning; and corrects a shift of an exposure position of the light beam; and a clock characteristic changer capable of changing a clock characteristic including at least one of frequency and phase of a write clock, wherein the hardware processor controls to execute two-dimensional exposure with the clock characteristic of the write clock, controls to execute the two-dimensional exposure at a predetermined relative position with respect to the mirror surface, and specifies a mirror surface used for formation of each portion of the detection pattern.

An optical scanning device has a housing body and an upper lid. The upper lid is formed at the end part thereof with a plurality of engagement holes, the housing body is provided at the sidewall thereof with a plurality of upper lid engaging projecting parts that project outward from a housing and are engaged with the engagement holes, an input gear is held to an end part of one side or the other side of the upper lid in a predetermined direction, and the plurality of upper lid engaging projecting parts are formed such that amounts of projecting outward from the housing are increased as the plurality of upper lid engaging projecting parts are positioned at a side near the input gear in the predetermined direction.

A moving member is disposed between an upper guide, which guides a conveyed transfer material and to which a voltage is applied from a power source, and a lower guide, which guides the conveyed transfer material, the upper guide being disposed on an upstream side with respect to a photosensitive drum in a conveyance direction of the transfer material. The moving member is supported by the upper guide, and is capable of abutting against and separating from the lower guide. By being pushed by the transfer material, the moving member transitions from a first state in which the moving member is abutted against the lower guide to a second state in which the moving member is separated from the lower guide.

In an optical writing device that deflects light beams from first and second light source sections and performs scanning by first and second scanning optical systems, in reflective optical elements disposed in the optical axis direction from after the polygon mirror to before a separation mirror, a number of hold points on each of a writing start side and a writing end side in scanning is same, and in reflective optical elements disposed from after the separation mirror up to a surface to be scanned, a number of hold points on a writing start side of the first scanning optical system is same (one) with that on a writing end side of the second scanning optical system, and a number of hold points on a writing end side of the first scanning optical system is same (two) with that on a writing start side of the second scanning optical system.

Provided is an optical scanning device, which includes a bottomed box-like casing (31) in which a ceiling side is opened, a rotating polygon mirror (35) housed in the casing (31) to deflect and scan light beams emitted from a light source, a driving motor (41) fixed to a bottom wall of the casing (31) to drive the rotating polygon mirror (35), and a lid member (37) that closes the ceiling side of the casing (31) and is fixed to the casing (31) via a fixing mechanism (311), wherein the fixing mechanism (311) is provided adjacent to a minimum separation part (B) of a sidewall of the casing (31) in which a distance from the rotating polygon mirror (35) is minimum.

An exposure device irradiates a photoconductor with light on the basis of an exposure signal and thereby forms an electrostatic latent image. A toner amount calculating unit (a) determines a distribution pattern of the electrostatic latent image on the basis of the exposure signal, (b) determines an electric field variation level of a target pixel, (c) determines an electric field intensity of the target pixel on the basis of a value of the target pixel in the distribution pattern and the electric field variation level, and (d) determines a toner consumption amount corresponding to the electric field intensity. Further, the toner amount calculating unit limits the electric field variation level to an uppermost value or less, the uppermost value corresponding to a value of the target pixel in the distribution pattern of the electrostatic latent image.

An optical scanning device has a housing body and an upper lid. The upper lid is formed at the end part thereof with a plurality of engagement holes, the housing body is provided at the sidewall thereof with a plurality of upper lid engaging projecting parts that project outward from a housing and are engaged with the engagement holes, an input gear is held to an end part of one side or the other side of the upper lid in a predetermined direction, and the plurality of upper lid engaging projecting parts are formed such that amounts of projecting outward from the housing are increased as the plurality of upper lid engaging projecting parts are positioned at a side near the input gear in the predetermined direction.

An image forming apparatus includes: a photoreceptor; a light source; a rotational polygon mirror including a plurality of mirror surfaces on an outer circumferential surface of a rotating body; and a hardware processor that: controls the light source to perform emission of a light beam; controls to rotate the rotational polygon mirror to perform a sequential primary scanning; and corrects a shift of an exposure position of the light beam; and a clock characteristic changer capable of changing a clock characteristic including at least one of frequency and phase of a write clock, wherein the hardware processor controls to execute two-dimensional exposure with the clock characteristic of the write clock, controls to execute the two-dimensional exposure at a predetermined relative position with respect to the mirror surface, and specifies a mirror surface used for formation of each portion of the detection pattern.

An image processing apparatus includes: a pipeline processor that inputs image data shifted 1 pixel at a time in a sub-scanning direction; a detector that inputs and holds each pixel of the image data, compares each pixel value of the held plurality of pixels, and detects an edge of a front end or a rear end of an object; a counter that counts a number of pixels that each pixel of the image data shifted in the sub-scanning direction; a distance coefficient determiner that uses a count value of the counter to determine a distance coefficient; a correction value calculator that calculates a correction value; a corrector that adds the correction value of each pixel to the pixel value of each pixel of the image data; and a position where the correction value is added is a position shifted at least N+1 pixels.