According to an embodiment, a signal generation circuit includes a generation unit configured to generate a second clock signal from division of a first clock signal and generate a timing signal with a cycle length that is a sum of a predetermined number of half-cycle periods of the second clock signal. A period changing unit of the signal generation circuit is configured to adjust the cycle length of the timing signal by changing a length of at least one half-cycle period of the second clock signal. An output unit of the signal generation circuit is configured to output the second clock signal and the timing signal.

A integrated light source module includes a planar optical waveguides layer having N light incident ports aligned with respect to each other, M light exit ports aligned with respect to each other, and optical waveguides connected to the N light incident ports and the M light exit ports, and N optical semiconductor devices facing each of the N light incident ports arranged so that light emitted from each of the N optical semiconductor devices can be incident on each of the N light incident ports, wherein light emitted from the M light exit ports can be applied to an object to be irradiated.

A light-emitting device includes a first connection wire and a second connection wire each connecting a first power supply wire and a second power supply wire, a second lead wire between the first connection wire and the second connection wire, and first lead wires including a first lead wire located opposite to the second lead wire from relative to the first connection wire. The first lead wires are parallel to one another and include first connection pads as first connections at ends connected to first signal wires. The second lead wire includes a second connection pad as a second connection at an end connected to a second signal wire. A distance between the second connection pad and a first connection pad of the first connection pads adjacent to the second connection pad is greater than a distance between adjacent ones of the first connection pads.

A light emitting device in which light emitting elements are arranged on a surface of a substrate is provided. Each of the light emitting elements comprises a light emitting layer, a reflective layer arranged between the light emitting layer and the surface, a first electrode arranged between the reflective layer and the light emitting layer, an optical distance adjustment layer arranged between the reflective layer and the first electrode, an insulating layer covering a peripheral portion of the first electrode and arranged, between two light emitting elements adjacent to each other, between the optical distance adjustment layer and the light emitting layer, and a conductive plug extending from the insulating layer to pass through the optical distance adjustment layer and reach a height of an upper surface of the reflective layer while being in electrical contact with the first electrode.

According to at least one embodiment, a lens mirror array includes a plurality of optical elements. An optical element of the plurality of optical elements includes an incident surface on which light is incident, an emitting surface configured to emit the light incident through the incident surface, at least one reflecting surface reflecting the light incident through the incident surface toward the emitting surface, and a light shielding portion configured to block the light. The incident surface includes an effective surface configured to pass effective light emitted from the emitting surface and a directional surface configured to direct unnecessary light to the light shielding portion.

An exposure head includes a first light emitting board group, a first lens array, a second light emitting board group, and a second lens array. The first light emitting board group is disposing a plurality of first light emitting boards each including a plurality of first light emitting elements disposed side by side in a second direction intersecting with the first direction. The plurality of first light emitting boards are disposed along the second direction and alternately in the first direction. The first lens array condenses light emitted from the plurality of first light emitting elements disposed on the first light emitting board group onto the surface of the image bearing member. The second light emitting board group is disposed in a manner separated with respect to the first light emitting board group in the first direction.

An image forming apparatus includes a photoconductor, light emitting elements, a developing device, a fixing device, and a controller. The photoconductor is charged. The light emitting elements form light spots on the photoconductor in order to form an electrostatic latent image on the photoconductor, and are provided to have a first distance with each other in a main scanning direction. The developing device develops an electrostatic latent image on the photoconductor to a toner image. The fixing device fixes the toner image to a sheet. The controller causes the light emitting elements to form first light spots on the photoconductor, causes the photoconductor to move toward the light emitting elements by a second distance shorter than the first distance in a sub-scanning direction orthogonal to the main scanning direction, and causes the light emitting elements to form second light spots on the photoconductor.

An image forming apparatus includes: an exposure head including a first light emitting chip, a second light emitting chip, a first lens fixed to a housing at a position facing the first light emitting chip, and configured to form an image of light emitted from a plurality of light emitting portions included in the first light emitting chip on a photoreceptor, and a second lens provided separately from the first lens, fixed to the housing at a position facing the second light emitting chip, and configured to form an image of light emitted from a plurality of light emitting portions included in the second light emitting chip on the photoreceptor; and a controller capable of controlling application of a voltage to each of a plurality of electrodes of the first light emitting chip and a plurality of electrodes of the second light emitting chip so as to form one pixel.

According to at least one embodiment, a lens mirror array includes a plurality of optical elements. An optical element of the plurality of optical elements includes an incident surface on which light is incident, an emitting surface configured to emit the light incident through the incident surface, at least one reflecting surface reflecting the light incident through the incident surface toward the emitting surface, and a light shielding portion configured to block the light. The incident surface includes an effective surface configured to pass effective light emitted from the emitting surface and a directional surface configured to direct unnecessary light to the light shielding portion.

A second electrode is laminated on a light emitting layer on an opposite side across the light emitting layer from a first electrode laminated on a silicon substrate. The second electrode is capable of transmitting light. A photoconductor drum is exposed to light by using light transmitted through the second electrode.