Sharp Kabushiki Kaisha Corporation

Semiconductor Energy Laboratory Co., Ltd.

Toshimasa Hamada

Nobuhiro Maezawa

Masumi Nakamichi

Shunpei Yamazaki

Satoshi Teramoto

Yuugo Goto

Yoshitaka Yamamoto

Sadayoshi Matsui

Saburo Yamamoto

Tetsuya Okamoto

Naoaki Yamaguchi

Toshihiko Yoshida

Osamu Yamamoto

Yukihiko Nakata

Toyoka Aimoto

Hirohisa Tanaka

Katunobu Awane

Takashi Itoga

Tetsuya Hanamoto

Shohichi Katoh

Masaru Iwasaki

Takahiro Funakoshi

Masahito Gotou

Shohichi Kato

Koji Miyake

A developing device which includes a developing roller which supplies a toner to a photoreceptor and a supply roller which performs supply of a toner to the developing roller and peeling of a toner from the developing roller, and applies a bias voltage to the developing roller so as to develop an electrostatic latent image formed on the photoreceptor with a toner. The developing device includes a first current measuring portion which measures a value of a current flowing in the developing roller, a second current measuring portion which measures a value of a current flowing in the supply roller, and a control portion which calculates a toner charging amount on the developing roller and a toner peeled amount by the supply roller based on measured results by the first current measuring portion and the second current measuring portion.

Developing device and image forming apparatus

Provided is a developing device employing single-component development in which in an upstream side of a most proximate area of a developing roller and a blade for regulating a toner layer, toner aggregation is made difficult to occur between the developing roller and the blade, and uniformity of the toner layer on the developing roller is increased, so as to be able to perform development which does not apply heavy stress and is excellent in uniformity. In the developing device, the blade is divided into two areas of a downstream area in a rotational direction of the developing roller including the most proximate part to the developing roller and an upstream area in a rotational direction of the developing roller not including the most proximate part, and adhesion between a toner and the blade in the upstream area is made smaller than that in the downstream area.

A transfer device and an image forming apparatus capable of forming an image of smooth image quality with little uneven density, are provided. An alternating voltage is applied so that a first period in which a first peak-to-peak voltage Vpp() is applied and a second period in which a second peak-to-peak voltage Vpp(), lower than the first peak-to-peak voltage, is applied are alternately repeated. In the alternating voltage to be applied, a transfer side potential to shift a toner from an intermediate transfer belt to recording paper sheet and an opposite transfer side potential to shift the toner from the recording paper sheet to the intermediate transfer belt are applied so as to alternate with each other. When fdenotes a frequency of the first period and fdenotes a frequency of the second period, ffis satisfied.

Transfer device and image forming apparatus

There is provided an image forming apparatus capable of realizing Improvement of an image density by improving dot reproducibility and reducing fog as well. An alternating voltage is applied to a development sleeve so that a first period during which a first peak-to-peak voltage Vpp() is applied and a second period during which a second peak-to-peak voltage Vpp() that is lower than the first peak-to-peak voltage is applied are repeated alternately. The alternating voltage to be applied is applied so that a development-side potential to move toner from the development sleeve to a photoreceptor and an opposite development-side potential to move toner from the photoreceptor to the development sleeve alternate with each other A frequency of the second period is lower than a frequency of the first period.

Image forming apparatus with a developing device utilizing an alternating bias voltage

A developing device capable of improving the image density and the dot reproducibility, and an image forming apparatus including the same are provided. A developing device applies an alternating voltage superimposed on a direct current voltage to a developing roller to thereby develop an electrostatic latent image formed on a photoreceptor with toner. A bias voltage waveform superimposed at this time has an original period (first period) in which each of a development-side electrical potential and an opposite development-side electrical potential is applied one time and a period (second period) in which a Vpp is gradually increased from the initial value to the maximum value.

Developing device and image forming apparatus that utilize a variable AC bias voltage

In an embodiment in which an electrostatic latent image formed on the surface of a photoreceptor is developed with a toner by applying an oscillating bias voltage in which a development-side electrical potential and an opposite development-side electrical potential alternate with each other, between a development sleeve of a development roller and the photoreceptor, the development-side electrical potential is applied in two stages, and, in the two-staged development-side electrical potential, the absolute value of a first electrical potential Vthat is initially applied is larger than the absolute value of a second electrical potential Vthat is subsequently applied.

Development method and image forming apparatus

A developing device for an image forming apparatus includes both a layer height restricting blade for controlling a thickness of the developer layer on a developer supply roller, and a spike-height restricting blade. The spike-height restricting blade is located downstream from the layer height restricting blade, and upstream from the position at which an electrostatic latent image bearing member and the developer supply roller are closest to each other. Preferably, the tip of the spike-height restricting blade is located downstream from a radial line along which a main magnetic pole of the device projects half of its maximum magnetic field strength.

There is provided an image forming apparatus capable of realizing improvement of an image density by improving dot reproducibility and reducing fog at the same time. An alternating voltage is applied to a development sleeve so that a first period during which a first peak-to-peak voltage Vpp() is applied and a second period during which a second peak-to-peak voltage Vpp() that is lower than the first peak-to-peak voltage is applied are repeated alternately. The alternating voltage to be applied is applied so that a development-side potential to move toner from the development sleeve to a photoreceptor and an opposite development-side potential to move toner from the photoreceptor to the development sleeve alternate with each other. The potential to be finally applied in the first period is preferably the development-side potential.

Image forming apparatus

A developing device and an image forming apparatus capable of restraining density irregularity and restraining a decline in image quality caused by adherence of carrier to a photoreceptor, are provided. An angle &#x3b1; is in a range of no less than 45 degrees nor more than 57 degrees, which is formed between a plane comprising a central line of magnetic pole formed by a regulating pole in a magnet roller and a rotating central axis of a developing sleeve and a plane comprising a central line of magnetic pole formed by a pumping pole and a rotating central axis of the developing sleeve. Further, an absolute value of the maximum value of strength of the magnetic pole formed by a main pole is in a range of no less than 120 mT nor more than 140 mT.

Developing device and image forming apparatus having the same

A method for forming an insulator film at a semiconductor temperature of 600&deg; C. or less comprises the steps of forming a first insulator film by oxidizing a surface of a semiconductor in an atmosphere containing oxygen atom radicals, and forming a second insulator film on the first insulator film by deposition without exposing the first insulator film to outside air.

Insulating film formation method, semiconductor device, and production apparatus

There is disclosed a manufacturing method of highly integrated circuits with thin-film transistors (TFTs) for use as peripheral driver circuitry in active-matrix liquid crystal display (LCD) panel with a pixel array each having a charge transfer control TFT, capable of facilitating formation of contact holes otherwise being difficult in cases where an anode oxide film is formed on gate electrodes of TFTs and lead wires both of which are made of anodizable metal, such as aluminum. The method includes execution of anodization while causing a resist mask to be disposed on part of the lead wire and electrode made of aluminum, thereby partly eliminating formation of the anode oxide film on the lead wire and electrode. At a later step of fabrication, each contact is formed by use of such portion that has no anode oxide film formed thereon. This may allow aluminum to be employed as lead wires while enabling easy fabrication of contacts therefor.

Method of forming semiconductor device

On a metallic wiring substrate, a first metallic layer is connected to a second metallic layer at a non-anodic-oxide section of the first metallic layer exposed at a bottom of a contact hole. The surface of the first metallic layer is anodically oxidized except for the non-anodic-oxide section. After resist is patterned so as to be entirely positioned on the surface of the first metallic layer, the first metallic layer is anodically oxidized, and the resist is removed therefrom. In such a manner, the non-anodic oxide section and the anodic oxide section are formed. This method makes it possible to produce the metallic wiring substrate having good insulation properties between layers easier than a method for forming the non-anodic-oxide section by etching the anodic oxide section.

Metallic wiring substrate

Disclosed is a photodetector with a multilayer filter. A light-receiving substrate is mounted on a recessed portion of a ceramic stem. An electrode pad is formed on a P-type layer of the light-receiving substrate while another electrode pad is formed on an N-type layer of the light-receiving substrate. An optical multilayer filter is formed on the light-receiving substrate except the regions of the electrode pads. Further, an epoxy transparent resin is poured into the recessed portion of the stem and then cured, so that a resin portion to cover the light-receiving substrate is formed. The optical multilayer filter is formed of amorphous low refractive index films made of SiC.sub.2 and amorphous high refractive index films made of TiO.sub.2. The amorphous high and low refractive index films are alternately stacked.

Photodetector with a multilayer filter and method of producing the same

A hyper-resolution optical device which can focus a beam of light to a diameter less than the diffraction limit. The optical device has an optical system disposed on a transmissive substrate. One component in the optical system is a hyper-resolution optical component which passes or reflects light and which has a central portion which does not pass or reflect light, respectively. The hyper-resolution optical component can be integrated with the transmissive substrate. Such optical devices are particularly suitable for optical pick-up devices, laser printers, sensors.

Growing community of inventors

Osaka, Japan

Toshimasa Hamada