An image reading apparatus includes a light emitter to irradiate a document with light, a first light guide to guide the light reflected by the document, an output device to output a readout signal obtained from the light reflected and guided by the first light guide, a base to correct shading in the readout signal, and circuitry to output a scanned image in which the shading of the document in the readout signal is corrected, based on correction data obtained from the readout signal of the base output from the output device, control a timing at which the light emitter emits the light and a timing at which the output device outputs a signal, and heat the first light guide with the light emitted from the light emitter before the output device outputs the readout signal of each of the document and the base.

A communication device includes a transmitter, a receiver, a clock signal line, a data signal line, a memory and a controller. The controller is configured to control the transmitter to transmit the clock signal and the confirmation signal where at least one of the clock signal and the confirmation signal are transmitted at a reference waveform condition and determine whether the transmitter receives an acquisition signal. The controller is configured to, if the transmitter does not receive the acquisition signal, control the transmitter to transmit the clock signal and the confirmation signal using a different waveform condition for at least one of the clock signal and the confirmation signal and if the transmitter receives the acquisition signal, update condition change information.

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.

A communication device includes a transmitter, a receiver, a clock signal line, a data signal line, a memory and a controller. The controller is configured to control the transmitter to transmit the clock signal and the confirmation signal where at least one of the clock signal and the confirmation signal are transmitted at a reference waveform condition and determine whether the transmitter receives an acquisition signal. The controller is configured to, if the transmitter does not receive the acquisition signal, control the transmitter to transmit the clock signal and the confirmation signal using a different waveform condition for at least one of the clock signal and the confirmation signal and if the transmitter receives the acquisition signal, update condition change information.

A parameter adjustment method and apparatus are provided. The parameter adjustment method for a communication device with a SerDes link includes: acquiring, by the communication device, a current ambient temperature of the communication device; and if according to a preset correspondence between a temperature range and a parameter, the current ambient temperature is determined to be not corresponding to a SerDes parameter of the communication device, adjusting the SerDes parameter of the communication device according to the correspondence. The SerDes parameter of the communication device is adjusted in real time, thereby improving reliability of a SerDes link of the communication device, and reducing a bit error rate of the SerDes link.

An image forming apparatus comprising: an exposing unit including: a first light source comprising a first light emitter and a first light receiver including a first electric output responsive to a received light quantity of the first light emitter; a second light source comprising a second light emitter and a second light receiver including a second electric output responsive to a received light quantity of the second light emitter; and a first light-source driver electrically connected to the first light source and the second light source. The first light-source driver includes: a first output terminal electrically connected to the first light emitter; a second output terminal electrically connected to the second light emitter; and an input terminal electrically connected to both the first electric output and the second electric output.

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.

An image reading apparatus includes a reference signal output portion, an image sensor, and an analog front end. The reference signal output portion is capable of outputting a first reference signal and a second reference signal, and changing difference in level between the first reference signal and the second reference signal according to a reference level control signal that is inputted. The image sensor outputs a primary image signal that is an analog signal in which a reference level is a level of the first reference signal that is inputted. The analog front end subjects the primary image signal to offset adjustment according to levels of the second reference signal and an offset control signal that are inputted, and further amplifies a signal having been subjected to the offset adjustment, to output a secondary image signal.

An image forming apparatus comprising: an exposing unit including: a first light source comprising a first light emitter and a first light receiver including a first electric output responsive to a received light quantity of the first light emitter; a second light source comprising a second light emitter and a second light receiver including a second electric output responsive to a received light quantity of the second light emitter; and a first light-source driver electrically connected to the first light source and the second light source. The first light-source driver includes: a first output terminal electrically connected to the first light emitter; a second output terminal electrically connected to the second light emitter; and an input terminal electrically connected to both the first electric output and the second electric output.

In a scanning apparatus, a controller is configured to obtain black reference data, compensated data based on digital data (scan data) by scanning a reference member with the light source turned off, and the black reference data. The controller further compares the compensated data with a first particular value. The controller executes the compensated data obtaining process with setting the light amount adjustment value to be a smaller value when the compensated data is greater than the first particular value, while with setting the light amount adjustment value to be a greater value when the compensated data is less than the first particular value. Further, the controller sets the light amount adjustment value to be a scan-time light amount adjustment value when the light amount adjustment value is equal to the first particular value. Then, the controller executes a scanning process according to the scan-time light amount adjustment value.