An image forming apparatus, including a photosensitive member, a scanning optical unit configured to scan the photosensitive member by laser light according to image information, a detection unit arranged in a position facing the photosensitive member and configured to output positional information on the laser light. The detection unit includes a detection portion into which the laser light reflected by the photosensitive member is incident, and a control unit configured to calculate a positional deviation amount of an irradiation position on the photosensitive member which is irradiated by the laser light based on the positional information output by the detection unit, and control the scanning optical unit to correct the positional deviation of the irradiation position of the laser light.

A rotating reflector is a resin rotating reflector including: a rotating part; and a blade provided around the rotating part and functioning as a reflecting surface, wherein the rotating part has a hole in which a rotary shaft is inserted.

A method for manufacturing optical scanning systems by which plural optical scanning systems with different effective scanning widths can be manufactured by changing a polygon mirror alone is provided. The method includes the steps of designing a first scanning optical system using a first polygon mirror corresponding to a first value of effective scanning width; designing a second scanning optical system provided with a second polygon mirror corresponding to a second value of effective scanning width, the second value being smaller than the first value, wherein a reference point of deflection is located at the position of the reference point of deflection of the first scanning optical system; and adjusting a size and a position of the scanning lens so as to adjust a lateral magnification in a cross section in the sub-scanning direction of the imaging optical system.

In an example, a method comprises: directing a sensing beam towards a reflective component of a print apparatus in a direction; detecting a reflected portion of the sensing beam at a detector comprising a two-dimensional sensing region; obtaining an indication of a location of the reflected portion of the sensing beam incident on the two-dimensional sensing region; and determining an orientation of the reflective component based on a correspondence between the location of the portion of the sensing beam on the two-dimensional sensing region and the direction of the sensing beam reflected by the component according to its orientation.

High speed laser scanning systems and methods are disclosed for imaging target samples. Embodiments of the laser scanning systems and methods include separating a laser beam into two or more different pathways and pulsing light along the two or more pathways. The different pathways intersect the surface of a moving mirror at different locations and light traveling in a pathway that is being approached by an edge of the moving reflective surface is turned off while light traveling in a different pathway that is farther from the edge of the moving reflective surface is turned on. Embodiments include reflective surfaces that form a rotating polygonal scanner. Further embodiments include recombining the two or more different pathways, focusing the laser light on a test sample, and imaging the light reflected from the test sample.

Provided is an optical deflector that detects an arbitrary deflection angle of a mirror part while avoiding the increase in the length of an optical sensor for detection of the deflection angle. An optical deflector 3 comprises: a mirror part 30 that has a flat reflection surface 38 and a grooved reflection surface 39, each of the flat reflection surface 38 and the grooved reflection surface 39 reflecting an incident light; and an actuator 32a to 32d that reciprocally turns the mirror part 30 about a rotation axis 36. The grooved reflection surface 39 has a plurality of longitudinal grooves 41 that extends parallel to the rotation axis 36. Each longitudinal groove 41 has a facing inclination surface 42a, 42b that is parallel to the rotation axis 36 and that has at least an opening-side portion of a facing inclination surface of a V-groove.

An optical scanning unit steers a light beam emitted from a laser diode in the main scanning direction by a polygon mirror. The laser diode, a collimator lens, an aperture, a first lens, the polygon mirror, and a condensing lens are sequentially placed in the optical system of the optical scanning unit. The laser diode emits a light beam in which divergent angles in intersecting two directions are different from each other. The direction in which the light beam divergent angle is large is aligned with the sub-scanning direction, and the direction in which the light beam divergent angle is small is aligned with the main scanning direction. The first lens has a first function to condense a beam in the sub-scanning direction and a second function to diffuse a beam in the main scanning direction.

A scanning optical apparatus includes a first light source unit, a second light source unit, a rotary polygon mirror and a casing provided with a bottom surface on which said deflection unit is disposed. The second light source unit is disposed at a position away from the bottom surface more than the first light source unit with respect to a rotational axis direction of the rotary polygon mirror. The casing is provided with first and second supporting surfaces for supporting the first and second light source. Both the first and second supporting surfaces are faced in a direction away from the bottom surface.

An optical head comprises a substrate on which optical elements are arranged in a main scanning direction, a lens unit that transmits light emitted from the optical elements or light entering the optical elements, and a holder that holds the lens unit. The holder has a sidewall extending in the main scanning direction. The sidewall has a hole at a position facing the lens unit. A fixing member is provided in the hole. The fixing member fixes the lens unit to the sidewall.

An optical member that refracts a light beam to diverge or focus the light beam, includes: at least three pairs of opposing surfaces. Each of the three pairs of opposing surfaces include a lens. Curvatures of the lenses at one side surfaces of the respective three pairs of surfaces are all the same, or curvatures of the lenses at one side surfaces of respective pairs of at least two pairs of the three pairs of surfaces are different from each other, and respective shortest distances between optical axes of the lenses at the one side surfaces of respective pairs of the at least two pairs of surfaces, and reference sides which are each any one of respective sides surrounding surfaces including the lenses are different from each other.