Abstract: An image forming apparatus includes a recording head and processing circuitry. The recording head includes a plurality of nozzles. The processing circuitry prints a reference adjustment pattern on a recording medium using a reference nozzle, which is one of the nozzles. When the recording medium is conveyed from the reference nozzle in a sub-scanning direction by a predetermined conveyance amount, the processing circuitry prints an adjustment pattern on the recording medium using a designated nozzle, which is apart by a predetermined distance with respect to a nozzle apart from the reference nozzle in the sub scanning direction by the predetermined conveyance amount. The processing circuitry detects the reference adjustment pattern and the adjustment pattern, computes a distance between the reference adjustment pattern and the adjustment pattern in the sub-scanning direction, and determines whether a standard deviation of the distance computed is equal to or larger than a predetermined value.

Abstract: An image forming apparatus includes a head, processing circuitry, and a reader. The head includes a first nozzle, a second nozzle, and a third nozzle at a position different from the first nozzle in a conveyance direction of a recording medium. The circuitry controls relative movement of the medium and the head along a main scanning direction and relative movement of a conveyance amount between the medium and the head along the conveyance direction. The circuitry controls the head to form a first test pattern with color ink discharged from the first nozzle, form a second test pattern with color ink discharged from the third nozzle, and form a mask image overlapping on or under the first pattern and overlapping on or under the second pattern with base ink discharged from the second nozzle. The reader reads positions of the first pattern and the second pattern on the medium.

Abstract: A position detector includes a reading device, a position reference member having a mark opposite the reading device, and circuitry. The circuitry controls the reading device to detect the contour of the processing target and the position of the image pattern on the processing target and the position of the mark and corrects a processing position for the processing target to offset distortion of the reading device.

Abstract: A reading device including a position reference member having a reference pattern having a line extending along a first direction of the position reference member, the position reference member movable in a second direction orthogonal to the first direction; a reader including a plurality of sensor chips arranged along the first direction, each of the sensor chips having a length defined by a plurality of pixels; and circuitry. The circuitry is configured to detect the reference pattern of the position reference member using the reader; determine coordinates of at least two sensor chips in the second direction, based on the detected reference pattern of the position reference member; and correct a position of a reading target in the second direction based on the coordinates determined for the at least two sensor chips of the reader in the second direction.

Abstract: An optical sensor device includes a first light source, a second light source, a sensor, and control circuitry. The first light source has a plurality of peak wavelengths in a wavelength range of 400 nm to 780 nm. The second light source emits ultraviolet light. The control circuitry adjusts a light amount of the first light source based on an output of the sensor in a state the first light source is on and the second light source is off, adjusts a light amount of the second light source based on an output of the sensor in a state the second light source is on and the first light source is off, and acquires a correction value of data output by the sensor, based on an output of the sensor in a state each of the first and second light sources is on with the light amount adjusted.

Abstract: A reading device includes a position reference member and a reader. The position reference member has a reference pattern that includes a line extending in a prescribed direction. The position reference member is configured to relatively move in a direction orthogonal to the prescribed direction. The reader includes a plurality of sensor chips, each of the sensor chips including a plurality of pixels. The reference pattern corresponds to each of the sensor chips of the reader.

Abstract: An image forming apparatus includes a conveyance device to convey a recording medium in a first direction and a second direction opposite the first direction; an image forming device; an imaging device; and circuitry to control the image forming apparatus. Controlled by the circuitry, the image forming device forms the colorimetric pattern on the recording medium that has been conveyed in the first direction by a predetermined distance after the marker pattern is formed. Controlled by the circuitry, after the colorimetric pattern is fixed, the circuitry causes the conveyance device to convey the recording medium in the second direction by an amount equivalent to a distance from the marker pattern to an imaging position by the imaging device plus a margin, conveys the recording medium in the first direction until the imaging device detects the marker pattern, and conveys the recording medium in the first direction to a colorimetry position.

Abstract: An optical sensor device includes a first light source, a second light source, a sensor, and control circuitry. The first light source has a plurality of peak wavelengths in a wavelength range of 400 nm to 780 nm. The second light source emits ultraviolet light. The control circuitry adjusts a light amount of the first light source based on an output of the sensor in a state the first light source is on and the second light source is off, adjusts a light amount of the second light source based on an output of the sensor in a state the second light source is on and the first light source is off, and acquires a correction value of data output by the sensor, based on an output of the sensor in a state each of the first and second light sources is on with the light amount adjusted.

Abstract: An image forming apparatus includes a conveyance device to convey a recording medium in a first direction and a second direction opposite the first direction; an image forming device; an imaging device; and circuitry to control the image forming apparatus. Controlled by the circuitry, the image forming device forms the colorimetric pattern on the recording medium that has been conveyed in the first direction by a predetermined distance after the marker pattern is formed. Controlled by the circuitry, after the colorimetric pattern is fixed, the circuitry causes the conveyance device to convey the recording medium in the second direction by an amount equivalent to a distance from the marker pattern to an imaging position by the imaging device plus a margin, conveys the recording medium in the first direction until the imaging device detects the marker pattern, and conveys the recording medium in the first direction to a colorimetry position.

Abstract: A reading device including a position reference member having a reference pattern having a line extending along a first direction of the position reference member, the position reference member movable in a second direction orthogonal to the first direction; a reader including a plurality of sensor chips arranged along the first direction, each of the sensor chips having a length defined by a plurality of pixels; and circuitry. The circuitry is configured to detect the reference pattern of the position reference member using the reader; determine coordinates of at least two sensor chips in the second direction, based on the detected reference pattern of the position reference member; and correct a position of a reading target in the second direction based on the coordinates determined for the at least two sensor chips of the reader in the second direction.

Abstract: A reading device includes a position reference member and a reader. The position reference member has a reference pattern that includes a line extending in a prescribed direction. The position reference member is configured to relatively move in a direction orthogonal to the prescribed direction. The reader includes a plurality of sensor chips, each of the sensor chips including a plurality of pixels. The reference pattern corresponds to each of the sensor chips of the reader.

Abstract: A position detector includes a reading device, a position reference member having a mark opposite the reading device, and circuitry. The circuitry controls the reading device to detect the contour of the processing target and the position of the image pattern on the processing target and the position of the mark and corrects a processing position for the processing target to offset distortion of the reading device.

Abstract: An image capturing device includes an image capturing unit, a moving unit, a detector, and a determiner. The image capturing unit includes an optical transmission member; and a sensor capturing an image of the subject via the optical transmission member. The moving unit moves the image capturing unit in an optical axis direction of the sensor. The detector detects a contamination from first and second images. The first and second images are captured by the sensor when the image capturing unit is located at first and second positions in the optical axis direction, respectively. The second position is spaced away from the subject than the first position in the optical axis direction. The determiner determines that a contamination is deposited on the optical transmission member when a difference in the number of pixels in which a contamination is detected between the first and second images is less than a threshold.

Abstract: An image capturing unit includes a sensor section that images a predetermined range including a subject; a reference chart section that is imaged by the sensor section with the subject; and an illumination light source that illuminates the subject and the reference chart section. The illumination light source is arranged at a position where a mirror reflection region that mirror reflects light entering from the illumination light source to the sensor section is outside a region of the subject and the reference chart section.

Abstract: A glossiness determining device includes: a light source; a two-dimensional sensor that receives reflected light containing a specular reflection component of a subject illuminated by the light source, and outputs an image of the subject; and a determining unit that determines glossiness of the subject by using a saturated image, which is the image of the subject output by the two-dimensional sensor and in which pixel values of a partial area are saturated.

Abstract: A color measuring device includes a housing; a sensor unit configured to capture an image of a region, the sensor unit being held to the housing; an illumination light source configured to illuminate the region, the illumination light source being held to the housing; a detecting unit configured to detect a distance between predetermined two points from image data of the region obtained by the sensor unit; a correcting unit configured to correct the image data including a subject whose color is to be measured according to a ratio of the detected distance to a reference distance; and a calculating unit configured to calculate a colorimetric value of the subject based on the corrected image data.

Abstract: An image capturing unit includes a sensor section that images a predetermined range including a subject; a reference chart section that is imaged by the sensor section with the subject; and an illumination light source that illuminates the subject and the reference chart section. The illumination light source is arranged at a position where a mirror reflection region that mirror reflects light entering from the illumination light source to the sensor section is outside a region of the subject and the reference chart section.

Abstract: An image capturing device includes an image capturing unit, a moving unit, a detector, and a determiner. The image capturing unit includes an optical transmission member; and a sensor capturing an image of the subject via the optical transmission member. The moving unit moves the image capturing unit in an optical axis direction of the sensor. The detector detects a contamination from first and second images. The first and second images are captured by the sensor when the image capturing unit is located at first and second positions in the optical axis direction, respectively. The second position is spaced away from the subject than the first position in the optical axis direction. The determiner determines that a contamination is deposited on the optical transmission member when a difference in the number of pixels in which a contamination is detected between the first and second images is less than a threshold.

Abstract: A glossiness determining device includes: a light source; a two-dimensional sensor that receives reflected light containing a specular reflection component of a subject illuminated by the light source, and outputs an image of the subject; and a determining unit that determines glossiness of the subject by using a saturated image, which is the image of the subject output by the two-dimensional sensor and in which pixel values of a partial area are saturated.

Abstract: An image capturing unit includes a sensor section that images a predetermined range including a subject; a reference chart section that is imaged by the sensor section with the subject; and an illumination light source that illuminates the subject and the reference chart section. The illumination light source is arranged at a position where a mirror reflection region that mirror reflects light entering from the illumination light source to the sensor section is outside a region of the subject and the reference chart section.