A light scanning apparatus includes a light source, a deflector configured to deflect a light flux from the light source, and an imaging optical system configured to guide the light flux deflected at the deflector onto a scanned surface. The imaging optical system consists of a single imaging optical element, wherein, on the optical axis of the imaging optical system, the conditions 0.15T2/Sk0.3 and 0.03d/K0.08 are satisfied. A condition 0.3B0.6 is satisfied at a condensing position Y where a scanning angle is greatest, when the condensing position Y in the main scanning direction on the scanned surface of the light flux deflected at the scanning angle by the deflector is expressed by Y=(K/B)tan(B).

An image forming apparatus includes a light source, an optical deflector, an optical deflector casing, a bearing, and a sound absorption unit. The optical deflector reflects and deflects an optical beam emitted from the light source, having a rotational reflection member disposed on a rotation shaft to perform optical scanning. The optical deflector casing seals a space in which the optical deflector. The bearing rotatably supports the rotation shaft of the rotational reflection member with respect to the optical deflector casing, and includes at least portion exposed to an external space outside the sealed space of the optical deflector casing. The sound absorption unit is disposed opposite the exposed portion of the bearing with the external space therebetween.

An image forming apparatus includes an optical scanning apparatus configured to scan a photoreceptor with a light beam having a scanning speed changing in accordance with a position in a main scanning direction, and a control unit configured to output a horizontal synchronization signal for determining a timing at which an image signal generation unit outputs an image signal to the optical scanning apparatus. The optical scanning apparatus includes a beam detection sensor that outputs a beam detection signal indicating a detection timing of the light beam, and a memory that stores timing correction information. The control unit corrects, based on the timing correction information, a reference time, and outputs the horizontal synchronization signal to the image signal generation unit at a timing after a period corrected from reception of the beam detection signal.

The optical scanning device includes a polygon mirror, one or more planar mirrors for reflecting the beam light so as to be led to a photosensitive drum, and a pressing member for pressing a back surface of a final planar mirror. The final planar mirror has a glass plate for allowing the beam light to pass therethrough and a reflection layer arranged on an opposite surface of the glass plate. The beam light passes through the glass plate and is reflected at the opposite surface side, so that a scanning line is curved on a surface to be scanned in a convex shape to one side in a sub-scanning direction. The final planar mirror is pressed by the pressing member so as to be curved, so that the scanning line on the surface to be scanned is adjustable to a flat shape.

An optical scanning apparatus includes a light source, an optical deflector having a rotary polygon mirror to deflect a light beam from the light source, a scanning optical system configured to focus the light beam deflected by the optical deflector on a target surface, a sync detecting sensor configured to determine a write start timing on the target surface, and a processing unit configured to correct detection data of the sync detecting sensor based on a measured value of a time needed for one revolution of the rotary polygon mirror.

An image forming apparatus includes a light source, an optical deflector, an optical deflector casing, a bearing, and a sound absorption unit. The optical deflector reflects and deflects an optical beam emitted from the light source, having a rotational reflection member disposed on a rotation shaft to perform optical scanning. The optical deflector casing seals a space in which the optical deflector. The bearing rotatably supports the rotation shaft of the rotational reflection member with respect to the optical deflector casing, and includes at least portion exposed to an external space outside the sealed space of the optical deflector casing. The sound absorption unit is disposed opposite the exposed portion of the bearing with the external space therebetween.

A step is formed between a first bottom portion and a second bottom portion, and the area where a sealing member and an upper cover adhere to each other increases by an amount corresponding to the provided step so that adhesiveness between the sealing member and the upper cover is enhanced.

Provided is a light scanning apparatus including a deflecting unit configured to deflect a first light flux from a first light source to scan a first scanned surface in a main scanning direction, a first imaging optical system and a reflecting element which are configured to guide the first light flux deflected by the deflecting unit to the first scanned surface, an optical element configured to guide the first light flux emitted from the first light source to the deflecting unit, and a holding member configured to hold the deflecting unit, the first imaging optical system, the reflecting element, and the optical element, in which the optical element and the reflecting element abut against the holding member.

An optical scanning device includes a first expander lens that expands beams emitted from a plurality of laser diodes in a main scanning direction. The beams emitted from the plurality of laser diodes are incident on the first expander lens, the first expander lens being a single lens. The plurality of laser diodes are disposed with optical paths of the beams from the plurality of light sources to a polygon mirror (rotary polygon mirror) overlapping each other in the main scanning direction when viewed from a direction along a rotary shaft of the polygon mirror.

An image forming apparatus includes: a polygon mirror formed with a plurality of reflection surfaces, and a generating device configured to generate a pulse signal required to modulate a laser beam based on image data. The generating device is further configured to generate a pulse signal by inserting or deleting a pulse signal having a width smaller than a width of a pulse signal corresponding to one pixel of the image data into or from a pulse signal corresponding to the image data based on information associated with deviation amounts between lengths of scanning lines formed by the plurality of reflection surfaces and a reference value, so as to adjust the lengths of the scanning lines formed by the plurality of reflection surfaces to be closer to the reference value.