A light-emitting device includes a base that extends in one direction; a light-emitting unit in which multiple light sources that are disposed in the one direction are supported by a supporting body that extends in the one direction and that is formed from a metal block; a spacer that is interposed between the base and the light-emitting unit in a direction of an optical axis of each light source; and a fixing unit that fixes the light-emitting unit to the base in a mode in which a compressive load is applied to the spacer.

An image forming apparatus includes a photoconductor, a light emitting substrate, and imaging optical systems, wherein an optical axis of the imaging optical systems are parallel, imaging magnifications of the imaging optical systems are substantially equal for the light emitting point groups, the imaging optical systems includes a first lens array, a second lens array, and apertures, central points of the light emitting point group exist in a first plane, central points of the imaging lenses exist in a second plane, central points of the apertures exist in a third plane, central points of the imaging lenses exist in a fourth plane, the first plane forms a non-zero predetermined angle with respect to a plane perpendicular to an optical axis direction, and the angle formed with respect to the plane perpendicular to the optical axis direction is greater in the order of the first, second, third, and the fourth plane.

A printing apparatus is provided. The apparatus comprises a light-emitting element, a light-receiving element including a first terminal and a second terminal, a reference current generator supplying a reference current, a comparator comparing a monitor current with the reference current, the light-receiving element supplying the monitor current to the second terminal in accordance with a light emission amount, a driver driving the light-emitting element based on an output of the comparator, and a reference voltage controller. The comparator includes a first input terminal connected to the second terminal and a second input terminal. The reference voltage controller supplies a reference voltage selected from at least two voltage values to the second input terminal, and to control the voltage of the second terminal to be a voltage according to the reference voltage.

A light emitting chip includes: a first data storage unit configured to store data for causing a first light emitting unit to emit light; a second data storage unit configured to store data for causing a second light emitting unit to emit light; a signal output unit configured to output a first trigger signal and a second trigger signal delayed with respect to the first trigger signal; and a drive unit configured to drive the first light emitting unit, in a case where the first trigger signal is output, based on data stored in the first data storage unit, and drive the second light emitting unit, in a case where the second trigger signal is output, based on data stored in the second data storage unit.

An image-forming apparatus includes a generating unit that generates correction data for correcting an unevenness in light amount of an exposure head using a read image of a correction chart, and a correction unit that corrects image data for image formation based on the correction data. The exposure head includes light-emitting chips each of which includes light-emitting elements. The correction chart includes a plurality of regions arranged in a direction, a first reference mark located on one side of the regions, and a second reference mark located on the other side of the regions. The generating unit determines partial regions respectively formed by the light-emitting chips within the regions based on positions of the first and second reference marks in the read image of the correction chart, and generate the correction data based on a result of measurement on the partial regions.

An image forming apparatus includes a fixing device including a fixing device frame, a chute rotatable between a path forming position and a path opening position, an optical sensor including a light-emitting element, and an actuator. The actuator has a shaft, a first lever configured to contact an anti-pivot rib, and a second lever configured to shield light emitted from the light-emitting element. The actuator is movable to a position where the first lever contacts the anti-pivot rib when the chute is at the path forming position, a position where the first lever and the anti-pivot rib are separated from each other when the chute is at the path forming position, and a position where the first lever and the anti-pivot rib are separated from each other when the chute is at the path opening position. The actuator and the optical sensor are supported by the fixing device frame.

An exposure device according to an embodiment may include: a holding member provided with a reference surface; an optical system being in contact with the reference surface and slidable in a first direction parallel to the reference surface; and a board including a light emitting element and being fixed to the holding member such that the optical system is sandwiched between the reference surface and the board.

An image forming apparatus includes a light emitting chip and at least one processor. The light emitting chip includes a plurality of light emitting elements, a DAC outputting a voltage corresponding to a setting value, and a circuit unit that supplies a current to the plurality of light emitting elements based on the voltage. At least one processor is configured to set the setting value such that one light emitting element included among the plurality of light emitting elements emits light of a predetermined amount, and correct image data pieces that respectively correspond to the plurality of light emitting elements based on first correction data for correcting amounts of light respectively emitted by the plurality of light emitting elements. The circuit unit supplies a current to each of the plurality of light emitting elements based on the corrected image data pieces.

The print head and light emitting elements, first and second drive circuits, and a control circuit. The light emitting elements and drive circuits are spaced from each other an arrangement pitch. The first drive circuit includes a first capacitor and sets a light emission level for the first light emitting element. The second drive circuit includes a second capacitor and sets a light emission level of the second light emitting element. The control circuit is connected to the first drive circuit by a first wiring and to the second drive circuit by a second wiring and controls voltages across the first and second capacitors individually. A difference between the length of the first wiring and the length of the second wiring is less than the arrangement pitch.

An exposure device according to an embodiment includes: a substrate in which light-emitting elements are mounted; an optical system which converges light emitted from the light-emitting elements; a holding member includes a holding member body which holds the substrate and the optical system, and a cut fringe projected from the holding member body; and a support member provided at a predetermined position in the holding member between the substrate and the optical system. The support member is formed of a cured agent attached to a shear surface of the cut fringe of the holding member, and the support member includes a contact surface with which the substrate is in contact.