Abstract: In a reading device, a light transmissive member has a front surface on which an original is placed. A peripheral member is adjacent to the light transmissive member, and includes a back surface in which a reference hole is formed. The reference hole includes a first edge and a second edge intersecting with each other. A reading sensor faces the back surface of the light transmissive member and the back surface of the peripheral member. The controller controls the reading sensor to read a reading range including the reference hole to obtain a read image, and determines a reference position in the reading range based on the read image. The reference position is determined to an intersection between the first edge and the second edge. The controller sets a reading start position based on the reference position.

Abstract: A scanning device includes a casing holding a original document table. A facing area is provided to the casing, and a rectangular hole is formed on the facing area. The rectangular hole has edges extending along a main scanning direction and edges extending along a sub-scanning direction. The edges extending along the sub-scanning direction are located in a central area of a photoelectric conversion element row of a sensor assembly in the main scanning direction. The sensor assembly scans the rectangular hole and detects a edge extending along the main scanning direction and a edge extending along the sub-scanning direction, thereby determines a scanning start position.

Abstract: In a reading device, a light transmissive member has a front surface on which an original is placed. A peripheral member is adjacent to the light transmissive member, and includes a back surface in which a reference hole is formed. The reference hole includes a first edge and a second edge intersecting with each other. A reading sensor faces the back surface of the light transmissive member and the back surface of the peripheral member. The controller controls the reading sensor to read a reading range including the reference hole to obtain a read image, and determines a reference position in the reading range based on the read image. The reference position is determined to an intersection between the first edge and the second edge. The controller sets a reading start position based on the reference position.

Abstract: A reading apparatus, having a document placement plate, a reader, a driving device, a cover, and a controller, is provided. The cover includes an alignment part and a protrusive part. The protrusive part includes an uneven surface and first and second edges forming outer edges of the uneven surface extending in a main scanning direction and in a sub-scanning direction, respectively. The controller is configured control the driving device to move the reader in the sub-scanning direction and the reader while being moved to read the protrusive part, and detect the first edge and the second edge in image data of the protrusive part read by the reader based on an image of the uneven surface and determine a reading range for the reader in the document placement plate based on positions of the first edge and the second edge.

Abstract: A reading apparatus, having a document supporting part, a reader, a driving mechanism, a reference density plate, and a controller, is provided. The controller controls the reader to perform a first reading action to read the reference density plate at a first position and adjust an amount of light, controls the reader to perform a second reading action under the light in the adjusted amount and create correction data for shading correction, controls the driving mechanism to move the reader from the first position toward a standby position, controls the reader while being moved from a second position toward a third position to perform a third reading action including a plurality of reading actions under the light in the adjusted amount, and inspects validity of the correction data by comparing read data obtained from signals resulted from the plurality of reading actions.

Abstract: A reading apparatus, having a document placement plate, a reader, a driving device, a cover, and a controller, is provided. The cover includes an alignment part and a protrusive part. The protrusive part includes an uneven surface and first and second edges forming outer edges of the uneven surface extending in a main scanning direction and in a sub-scanning direction, respectively. The controller is configured control the driving device to move the reader in the sub-scanning direction and the reader while being moved to read the protrusive part, and detect the first edge and the second edge in image data of the protrusive part read by the reader based on an image of the uneven surface and determine a reading range for the reader in the document placement plate based on positions of the first edge and the second edge.

Abstract: A reading apparatus, having a document supporting part, a reader, a driving mechanism, a reference density plate, and a controller, is provided. The controller controls the reader to perform a first reading action to read the reference density plate at a first position and adjust an amount of light, controls the reader to perform a second reading action under the light in the adjusted amount and create correction data for shading correction, controls the driving mechanism to move the reader from the first position toward a standby position, controls the reader while being moved from a second position toward a third position to perform a third reading action including a plurality of reading actions under the light in the adjusted amount, and inspects validity of the correction data by comparing read data obtained from signals resulted from the plurality of reading actions.

Abstract: An image scanner has an operation clock generator, a photoelectric converter, an AD converter configured to convert the analog pixel signals serially output by the photoelectric converter to digital pixel data by sampling the analog pixel signals in accordance with an operation clock generated by the operation clock generator, a data generator configured to generate read image data representing an read image of the original based on the pixel data converted by the AD converter, a resolution setter configured to set a reading resolution in the sub scanning direction, and a line period determiner configured to determine the line period to be (integer+decimal value) times a modulation period based on the reading resolution set by the resolution setter, the modulation period being inversion of the modulation frequency. The integer is greater than one and the decimal value is determined based on the reading resolution.

Abstract: An image scanner has an operation clock generator, a photoelectric converter, an AD converter configured to convert the analog pixel signals serially output by the photoelectric converter to digital pixel data by sampling the analog pixel signals in accordance with an operation clock generated by the operation clock generator, a data generator configured to generate read image data representing an read image of the original based on the pixel data converted by the AD converter, a resolution setter configured to set a reading resolution in the sub scanning direction, and a line period determiner configured to determine the line period to be (integer+decimal value) times a modulation period based on the reading resolution set by the resolution setter, the modulation period being inversion of the modulation frequency. The integer is greater than one and the decimal value is determined based on the reading resolution.

Abstract: An image forming apparatus includes a polygon mirror having a first mirror surface and a controller. The controller is configured to: acquire a detection interval corresponding to one rotation of a polygon mirror; start scanning exposure with a first beam deflected by the first mirror surface, in response to elapse of a first time period after a detection signal has been detected; and start scanning exposure with a second beam deflected by the first mirror surface, in response to elapse of a second time period after the detection signal has been detected. The second time period is calculated based on the detection interval.

Abstract: An image forming apparatus includes a polygon mirror having a first mirror surface and a controller. The controller is configured to: acquire a detection interval corresponding to one rotation of a polygon mirror; start scanning exposure with a first beam deflected by the first mirror surface, in response to elapse of a first time period after a detection signal has been detected; and start scanning exposure with a second beam deflected by the first mirror surface, in response to elapse of a second time period after the detection signal has been detected. The second time period is calculated based on the detection interval.

Abstract: An image forming apparatus includes a control unit performing a first rotation control process of switching on and off current-supplying in accordance with a change in a first deviation between a first rotation speed of a brushless motor and a target speed regardless of a change in an integrated value of the first deviation; a second rotation control process of calculating an integrated value of a second deviation between a second rotation speed of the brushless motor and the target speed, and switching on and off the current-supplying in accordance with a change in the second deviation and a change in the integrated value of the second deviation; and a rotation control switching process of switching to the second rotation control process when it is determined that the first deviation has entered a prescribed range during the first rotation control process.

Abstract: A light scanning apparatus includes: a light emission unit emitting a first light beam and a second light beam; a motor; a rotary polygon mirror rotated by the motor, forming two scanning lines on a scan object at the same time; an optical sensor detecting the first light beam and the second light beam deflected by the rotary polygon mirror; a deviation measurement unit measuring a deviation amount of starting positions of the two scanning lines on the scan object based on a first detection timing at which the optical sensor detects the first light beam and a second detection timing at which the optical sensor detects the second light beam; and a motor control unit controlling rotation of the motor based on the second detection timing in a measurement non-execution period, and controls rotation of the motor without using the first detection timing in a measurement execution period.

Abstract: A high-voltage power supply for applying a developing bias to a developing roller of an image forming apparatus is provided. The high-voltage power supply includes: a developing bias application unit that applies a developing bias to the developing roller in accordance with a control voltage that is input therein; a developing bias detection unit that detects the developing bias applied to the developing roller; a control voltage adjustment unit that adjusts the control voltage input to the developing bias application unit such that the developing bias detected by the developing bias detection unit approaches a predetermined target value; and a condensation determination unit that determines condensation of the developing bias application unit based on the control voltage.

Abstract: A light scanning apparatus includes: a light emission unit emitting a first light beam and a second light beam; a motor; a rotary polygon mirror rotated by the motor, forming two scanning lines on a scan object at the same time; an optical sensor detecting the first light beam and the second light beam deflected by the rotary polygon mirror; a deviation measurement unit measuring a deviation amount of starting positions of the two scanning lines on the scan object based on a first detection timing at which the optical sensor detects the first light beam and a second detection timing at which the optical sensor detects the second light beam; and a motor control unit controlling rotation of the motor based on the second detection timing in a measurement non-execution period, and controls rotation of the motor without using the first detection timing in a measurement execution period.

Abstract: There is provided an image forming device, including: a first electrical load; a second electrical load; a voltage generation circuit that generates a second voltage to be applied to the second electrical load; a shunt circuit that located between an output side of the voltage generation circuit and the first electrical load; and a controller that executes first control of controlling the shunt circuit to change a first voltage applied from the shunt circuit to the first electrical load to a first target level, and second control of controlling the voltage generation circuit to change the second voltage to a second target level. The controller executes voltage change suppression control of controlling the second voltage such that change of the second voltage becomes gentler as a difference between the first voltage and the first target level becomes larger.

Abstract: A high-voltage power supply for applying a developing bias to a developing roller of an image forming apparatus is provided. The high-voltage power supply includes: a developing bias application unit that applies a developing bias to the developing roller in accordance with a control voltage that is input therein; a developing bias detection unit that detects the developing bias applied to the developing roller; a control voltage adjustment unit that adjusts the control voltage input to the developing bias application unit such that the developing bias detected by the developing bias detection unit approaches a predetermined target value; and a condensation determination unit that determines condensation of the developing bias application unit based on the control voltage.

Abstract: There is provided an image forming device, comprising: a first electrical load; a second electrical load; a voltage generation circuit that generates a second voltage to be applied to the second electrical load; a shunt circuit that located between an output side of the voltage generation circuit and the first electrical load; and a controller that executes first control of controlling the shunt circuit to change a first voltage applied from the shunt circuit to the first electrical load to a first target level, and second control of controlling the voltage generation circuit to change the second voltage to a second target level. The controller executes voltage change suppression control of controlling the second voltage such that change of the second voltage becomes gentler as a difference between the first voltage and the first target level becomes larger.