An imaging device according to the present disclosure includes: a clock signal generator; a plurality of light-receiving pixels; a plurality of gate circuits; and a plurality of counters. The clock signal generator supplies a first clock signal to a clock signal path. The plurality of light-receiving pixels is provided side by side in the first direction and grouped into a plurality of pixel groups in the first direction. The plurality of light-receiving pixels each includes a light-receiving circuit, a comparison circuit, and a latch circuit. The comparison circuit performs a comparison operation on the basis of a pixel signal and a reference signal having a ramp waveform. The latch circuit latches a time code on the basis of a result of comparison. The plurality of gate circuits is each configured to output a signal in a clock signal path as a second clock signal. The plurality of gate circuits each controls, on the basis of a control signal, whether or not to output the second clock signal. The plurality of counters each generates the time code on the basis of the second clock signal supplied from the corresponding gate circuit and supplies the generated time code to two or more light-receiving pixels belonging to the corresponding pixel group.

An image reading device can easily increase or improve the depth of field. The image reading device includes a lens array (1) including lenses (2) arrayed in a main scanning direction, a sensor array (4) including sensor elements (4) arrayed in the main scanning direction to receive light converged by the lenses (2), and an overlap preventer located between the lens array (1) and the sensor array (4) to prevent an overlap of images formed by the lenses (2). The overlap preventer includes a slit assembly (5) including at least one specific-light blocker or optically transparent columns (13).

An object of one embodiment of the present invention is to accurately derive an inclination of a line image sensor. One embodiment of the present invention is an image reading apparatus including: a line image sensor in which reading elements for reading an image are arrayed in a predetermined direction; a first derivation unit configured to, based on read data acquired by reading a chart on which a plurality of dot patterns is printed with the line image sensor, derive coordinates of each of the plurality of dot patterns; a second derivation unit configured to derive an inclination angle of the line image sensor based on the coordinates derived by the first derivation unit; and a first calculation unit configured to calculate a first correction value for correcting the inclination of the line image sensor based on the inclination angle derived by the second derivation unit.

An object of one embodiment of the present invention is to accurately derive an inclination of a line image sensor. One embodiment of the present invention is an image reading apparatus including: a line image sensor in which reading elements for reading an image are arrayed in a predetermined direction; a first derivation unit configured to, based on read data acquired by reading a chart on which a plurality of dot patterns is printed with the line image sensor, derive coordinates of each of the plurality of dot patterns; a second derivation unit configured to derive an inclination angle of the line image sensor based on the coordinates derived by the first derivation unit; and a first calculation unit configured to calculate a first correction value for correcting the inclination of the line image sensor based on the inclination angle derived by the second derivation unit.

An image forming apparatus performs the following. An imaging range imaged by each of the plurality of imaging sensors includes an overlapping portion between the imaging sensors adjacent in a width direction orthogonal to a conveying direction along the conveying path. A hardware processor performs a calibration operation of a first sensor based on a color measuring result of a predetermined inspection image measured within a standard imaging range of the first sensor among the plurality of imaging sensors, and a standard imaging result within the standard imaging range imaging an inspection image with a same pattern as the inspection image. The hardware processor compares imaging results by the plurality of imaging sensors in the overlapping portions and performs the calibration operation of another sensor different from the first sensor using the standard imaging result as a standard.

A photoelectric conversion device includes a plurality of pixels configured to output analog voltage signals in response to incident light; an analog memory configured to store the analog voltage signals output from the plurality of pixels; and an analog/digital (A/D) converter configured to perform A/D conversion on the analog voltage signal from the analog memory. The plurality of pixels includes N pixels configured to simultaneously output analog voltage signals to the analog memory. The A/D converter includes (N−1) or less A/D converters configured to perform A/D conversion on the analog voltage signals that have been simultaneously output from the N pixels and stored in the analog memory.

A photoelectric conversion device includes a plurality of pixels configured to output analog voltage signals in response to incident light; an analog memory configured to store the analog voltage signals output from the plurality of pixels; and an analog/digital (A/D) converter configured to perform A/D conversion on the analog voltage signal from the analog memory. The plurality of pixels includes N pixels configured to simultaneously output analog voltage signals to the analog memory. The A/D converter includes (N−1) or less A/D converters configured to perform A/D conversion on the analog voltage signals that have been simultaneously output from the N pixels and stored in the analog memory.

An image acquisition apparatus comprising pixels each including sub-pixels, the apparatus comprising signal holding units for holding signals from the sub-pixels, and a signal processing unit for acquiring and processing each of the signals from the signal holding units, wherein the signal processing unit includes a first mode of amplifying, by a predetermined amplification factor, the signals held by the signal holding units and individually outputting the signals, and a second mode of amplifying, by amplification factors at least some of which are different from the amplification factor in the first mode, the signals held by the signal holding units to add and output the signals.

An image acquisition apparatus comprising pixels each including sub-pixels, the apparatus comprising signal holding units for holding signals from the sub-pixels, and a signal processing unit for acquiring and processing each of the signals from the signal holding units, wherein the signal processing unit includes a first mode of amplifying, by a predetermined amplification factor, the signals held by the signal holding units and individually outputting the signals, and a second mode of amplifying, by amplification factors at least some of which are different from the amplification factor in the first mode, the signals held by the signal holding units to add and output the signals.

An outer peripheral member disposed at an outer periphery of a platen glass includes first and second reference surfaces. The first reference surface is a lower surface of an area extending along a side edge portion of the platen glass at an end in a main scanning direction. The second reference surface is located adjacent to the first reference surface in a second direction and differs in light reflectance from the first reference surface. An image processing portion determines whether outer periphery pixel data of an outer periphery area in line image data acquired successively while a scanning unit is moving, satisfies a border condition. A unit driving portion positions the scanning unit to a home position by moving the scanning unit a predetermined distance from where the scanning unit is located when it is determined that the outer periphery pixel data satisfies the border condition, and stops it.