Ricoh Company, Ltd.

Masashi Tachi

Tomohide Takenaka

Masaki Sukesako

Keita Sone

Kazuaki Kamihara

Masayoshi Nakayama

Takuma Higa

Yuichi Aizawa

Shinya Tanaka

Kohei Matsumoto

An image forming apparatus includes an image former, a detector, and circuitry. The image former forms a toner pattern with a first line screen; and forms a toner image based on image data, with a second line screen. The detector detects density unevenness of the toner pattern, formed by the image former, in a main scanning direction. The circuitry is configured to calculate a first correction amount from the density unevenness detected by the detector; create a gradation correction table that reduces the density unevenness based on the first correction amount; and correct the first correction amount by a second correction amount corresponding to the second line screen, in a case where the first line screen is different from the second line screen.

Image forming apparatus

An image forming apparatus includes an image forming device, a first transfer device including a first mover, a second transfer device including a second mover, a transfer-pressure changer, a detector, and circuitry. The detector detects a toner image and outputs a detection value indicating an amount of toner of the toner image adhering to the second mover. The circuitry calculates a variable value for the amount of toner varying with a change in a transfer pressure, based on the detection value and a target value of the amount of toner of the toner image to be transferred and adhere to the second mover, reflects the calculated variable value in the detection value to correct the detection value, adjusts an image-forming condition based on the corrected detection value, and sets the image-forming condition of the toner image in the image forming device based on the corrected detection value.

Image forming apparatus and image forming method

An image forming apparatus includes an image forming device, a density deviation detector, and processing circuitry. The circuitry performs a density deviation adjustment mode to: cause the image forming device to form a first image pattern having a uniform image density in the width direction on a surface of an image bearer; cause the detector to detect a first image density deviation in the width direction in the first pattern; adjust the first deviation based on a detection result of the first pattern; cause the image forming device to form a second image pattern on a surface of the image bearer after adjustment of the first deviation; cause the detector to detect a second image density deviation in the width direction in the second pattern; and correct a light intensity sensitivity in adjusting the second deviation, based on a detection result of the second pattern.

Image forming apparatus and image formation method

An image forming apparatus includes a latent image bearer to bear a latent image, a potential sensor having a vibrator driven by a drive frequency to detect a surface potential of the latent image bearer, a developer bearer to bear developer that develops the latent image on the latent image bearer, and a power supply to apply a superimposed voltage obtained by superimposing an alternating voltage on a direct current voltage on the developer bearer. The frequency of the alternating voltage is not a multiple of the drive frequency and is a value obtained by adding a predetermined value to a multiple of the driving frequency.

Image forming apparatus and voltage application method

An electrophotographic image forming apparatus includes a latent image bearer to rotate and bear a latent image, a charging device to charge the a latent image bearer, a developing device to develop the latent image with developer including toner and use a developing voltage including an AC component, and a lubricant applicator to apply lubricant onto a surface of the latent image bearer. An amount of the lubricant applied by the lubricant applicator onto the latent image bearer per centimeter in an axial direction of the latent image bearer is equal to or greater than 0.845 mg for a running distance of 1.0 kilometer of the latent image bearer, and a difference between a largest value and a smallest value of the developing voltage is in a range of 200 V to 400 V.

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Kanagawa, Japan

Masashi Tachi