Mitsubishi Denki Kabushiki Kaisha

Ricoh Company, Ltd.

Nec Corporation

Mitusbishi Denki Kabushiki Kaisha

Mitsutaka Iwasaki

Hisashi Kawafuji

Gourab Majumdar

Toru Iwagami

Khalid Hassan Hussein

Tomonori Tanaka

Toshiaki Shinohara

Tooru Iwagami

Naoki Ohta

Yuuto Watanabe

Hitoshi Toda

Gorab Majumdar

Hidetoshi Suzuki

Yutaka Sato

Yukio Kadowaki

Akihisa Yamamoto

Kazuaki Hiyama

Shinji Hatae

Toshihiro Tsukagoshi

Fumitaka Tametani

Michihito Ootsuki

Kazuhiro Miyazaki

Masazumi Sukekawa

An image forming apparatus includes a rotational conveying unit for conveying a recording medium by rotating about a rotational axis. A head unit includes n nozzle rows in a conveying direction perpendicular to an axial direction parallel to the rotational axis. Each of the n nozzle rows includes nozzles aligned as a nozzle row in the axial direction. Each n nozzle row is arranged at a distance of dto d(n&#x2212;1) from a predetermined reference nozzle row. A circuit outputs a rotational amount detection signal, and a conveying amount detection signal, and generates a discharge synchronization signal based on the detected rotational amount detection signal and the detected conveying amount detection signal, then generates a nozzle row timing signal based on the distance of the dto d(n&#x2212;) and the discharge synchronization signal, and generates discharge data based on the discharge synchronization signal and the nozzle row timing signal.

Image forming apparatus and signal control method in image forming apparatus

An image forming apparatus includes a rotating body to form an image, a sensor to detect a home position of the rotating body, a processor to acquire image density data of the image formed by the rotating body in odd-numbered rotation and even-numbered rotation of the rotating body separately based on a rotation home position signal output by the sensor, extract an image density fluctuation caused by a rotation of the rotating body, and correct an image forming condition based on the image density fluctuation.

Image forming apparatus and image forming method

An image processing device includes an external memory interface to write image data to an image memory, and an inclination correction circuit. The inclination correction circuit generates coordinate information based on inclination information, detects, from the coordinate information, a minimum sub-scanning coordinate in each of divided areas of the image data, generates first read addresses for reading the divided areas of the image data from the image memory based on the minimum sub-scanning coordinate, reads the divided areas of the image data from the image memory based on the first read addresses, writes the divided areas of the image data to an internal memory, generates second read addresses for reading the divided areas of the image data from the internal memory based on the coordinate information, and reads the divided areas of the image data from the internal memory based on the second read addresses.

Image processing device, image forming apparatus, image processing method, and non-transitory recording medium to correct an inclination of image data in the image memory relative to an output medium

An image processing device includes a writing circuit to write image data to a first memory, a second memory with a capacity of lines, a coordinate generating circuit to generate coordinate information based on inclination information, a deviation calculating circuit to calculate a maximum deviation amount of the image data from the coordinate information, a division number calculating circuit to calculate a division number based on the number of the lines and the deviation amount, an address generating circuit to generate an address for reading each of divided areas of the image data from the first memory, a burst length calculating circuit to calculate a burst length based on the division number and a main scanning width of the image data, and a transferring circuit to read and burst-transfer the image data from the first memory to the second memory based on the address and the burst length.

Image processing device for correcting skew deviation, image forming apparatus, image processing method for correcting skew deviation, and non-transitory recording medium

An image processing device includes a writing circuit to write image data to an image memory and detect a write line number, a coordinate generating circuit to generate coordinate information based on inclination information, detect a minimum sub-scanning coordinate in each of divided areas of the image data, and generate first read addresses for reading the divided areas from the image memory, a reading circuit to read the divided areas from the image memory and detect a read line number, a reading control circuit to bring the reading circuit into a standby state and cancel the standby state, and a memory control circuit to generate write addresses for writing the divided areas to a memory, sequentially write the read divided areas to the memory, generate second read addresses for reading the divided areas from the memory, and sequentially read the divided areas from the memory.

Adjusting image data using divided areas

A light-source-driving control device thins a pixel at an edge portion of image data by a first pixel width; sets a second pixel width at the edge portion such that a ratio between the first and second pixel widths is constant; creates light amount information including a first light amount with which a pixel not included in the set second pixel width is exposed, and a second light amount with which a pixel included in the second pixel width is exposed; selects the first or second light amount based on a power-modulation control signal; drives light sources according to the selected light amount and a light-source-modulation pulse signal; and counts an addition value of pixel density considering a pixel width and a light amount, based on a data-width setting signal based on the second pixel width, and on a light-amount setting signal based on the light amount information.

Light-source-driving control device, image forming apparatus, and light-source driving method

A multi-beam laser light-intensity control circuit includes laser diodes; a light-receiving element for receiving a laser beam emitted from each laser diode and outputting a current corresponding to the light intensity of the received laser beam; and an automatic power control circuit for automatically controlling output power of each laser diode based on the current output from the light-receiving element. The automatic power control circuit includes a current/voltage conversion unit for converting the current output from the light-receiving element into a voltage; an error amplifying circuit for amplifying a difference voltage between the voltage output from the current/voltage conversion unit and a predetermined reference voltage; storing circuits each configured to store the difference voltage output from the error amplifying circuit in association with the corresponding laser diode; and drive current generating units each configured to generate a drive current for the corresponding laser diode based on the difference voltage.

Multi-beam laser light-intensity control circuit and optical scanning apparatus including the same

A semiconductor integrated circuit device controlling a first light amount of light emitted from a light source based on a second light amount of light entering a light amount detection part so that the first light amount becomes a target level is disclosed. The semiconductor integrated circuit device includes a comparison part configured to compare a voltage corresponding to the second light amount and a reference voltage corresponding to the target level; and a drive current control part configured to control a drive current supplied to the light source based on the result of the comparison by the comparison part. The drive current control part includes a return light identification part configured to determine whether the second light amount includes a third light amount of return light occurring discontinuously.

Semiconductor integrated circuit device, optical scanner using same, image forming apparatus using optical scanner, and return light identification method

A PLL control circuit, which outputs a PLL clock in response to a reference clock, is provided with a frequency adjustment circuit which performs frequency adjustment such that the PLL clock frequency is substantially constant even when the reference clock varies. The frequency adjustment circuit changes a set value in a counter, which determines the PLL clock frequency, in accordance with the variation in the reference clock frequency.

PLL control circuit

The present invention provides an image processing device, an image processing method, and an image reading method, by which encoded data can be easily generated from sub-sampled image data, without a complicated circuit or an increase in the data amount. A one-dimensional wavelet transform in a predetermined direction is omitted in stagewhere componentsandof input image data have been sub-sampled. When coefficient data generated through such a two-dimensional wavelet transform are to be encoded, sub-bands that are not contained in the coefficient data in comparison with the coefficient data of a componentshould be considered to have been truncated.

Image processing device, image processing method, and image reading method

An inverter circuit to reduce a resistor for overcurrent detection and decrease the number of filters in an inverter circuit for supply polyphase power. Transistors each having a current detection terminal and a protective diode for regenerative current are adopted as switching elements on an 'L' side and their current detection terminals are connected in common to a resistor. Therefore, a voltage drop caused by a current flowing in the resisytor becomes larger when an overcurrent flows in at least one of the transistors and further when an overcurrent flows in a switching element on an 'H' side even if no overcurrent flows in any one of the transistors.

Inverter circuit

Semiconductor device

A power module is provided with an insulating substrate with a heat sink being bonded to one surface thereof and a circuit pattern being formed on the other surface. The circuit pattern is formed by an electrode layer. A switching semiconductor element and a free wheeling diode that is connected to a switching semiconductor element in anti-parallel therewith are placed on the circuit pattern. A controlling IC for controlling the switching semiconductor element is placed on the free wheeling diode. Thus, it is possible to make the entire power module compact, and it becomes possible to provide an inexpensive power module which can prevent the controlling IC from malfunctioning due to heat generated by the switching semiconductor element.

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Kanagawa, Japan

Mitsutaka Iwasaki