Samsung Electronics Co., Ltd.

Sang-don Lee

Myung-kook Ahn

In-yong Song

Sung-min Park

Jin-geun Kwak

Suk-ho Yoon

Mitsuru Oikawa

Do-Young Rhee

Jong-uk Seo

Jong-pil Jun

Byoung-kyun Kim

Keon-Hun Lee

Kee-Won Lee

Shinichi Hasatomi

An apparatus for evaluating the quality of a crystal includes an optical device that measures a surface reflectance of a wafer in which a V-pit is formed; and a data processing unit that calculates a threading dislocation density by calculating a difference in surface reflectance of the wafer that is measured by the optical device.

Apparatus for evaluating quality of crystal, and method and apparatus for manufacturing semiconductor light-emitting device including the apparatus

A developing device to supply toner in a developer, including a development member which receives the developer on an outer circumferential surface thereof and supplies the toner to the image bearing member, a first regulation member including a first regulating portion that forms a first doctor gap between the outer circumferential surface of the development member and the first regulating portion, and a second regulation member disposed on an upstream side of the first regulation member in a rotational direction of the development member and includes a second regulating portion that forms a second doctor gap between the outer circumferential surface of the development member and the second regulating portion, the second doctor gaps at a central portion and both end portions in a longitudinal direction of the development member being different from each other.

Developing device to form a uniform developer layer on a developing member and electrophotographic image forming apparatus using the same

Provided is an apparatus and method for supplying a charge voltage to an organic photoconductor (OPC) drum. The apparatus includes a storage unit for storing first service life information of the OPC drum according to a first supplying method, and second service life information of the OPC drum according to a second supplying method, a sensor unit for measuring information about conditions surrounding the apparatus, a control unit for selecting one of the first and second supplying methods according to the measured information and determining a charge voltage corresponding to the service life information according to the selected method, and a voltage supplying unit using the selected method to supply the determined charge voltage to the OPC drum.

Apparatus and method for supplying charge voltage to organic photoconductor drum

A developer agitator of an image forming device capable of improving the electrification rate of a developer is disclosed. The developer agitator includes a rotatable shaft and an agitating wing disposed on the circumferential surface of the shaft. The agitating wing has an uneven part formed to increase the contact area with a developer. The developer agitator can obtain an electrification rate of the developer required for high speed printing, thereby allowing the image forming device to be operated at a high speed.

Developer agitator increasing electrification rate of developer, and developing apparatus and image forming device having the same

An image forming apparatus is provided that forms an image with liquid developer, and a method thereof. The image forming apparatus includes a plurality of photoconductors on which developer images having carrier rates different from each other are formed with corresponding liquid developers. An image transfer member is disposed to form transfer nips with the respective photoconductors in such a manner that the developer images of the respective photoconductors are overlappingly transferred onto the image transfer member according to a transfer order predetermined on the basis of the carrier rates thereof. The developer images from the respective photoconductors are moved to an image receiving medium. Since the developer images formed on the plurality of photoconductors are overlappingly transferred onto the image transfer member according to the predetermined transfer order, the developer images previously transferred at the prior transfer nips are substantially prevented from generating a squeezed carrier beyond a predetermined limit at the posterior transfer nips. The squeezed carrier is substantially prevented from accumulating beyond the predetermined limit at the inlet side of the posterior transfer nips when the developer images are transferred from the respective photoconductors to the image transfer member.

Image forming apparatus and method thereof

An image transfer member, an image transfer device and an image forming system employing the image transfer member and device are disclosed. The image transfer member comprises a base layer, and a surface layer formed from a semi-conductive material above the base layer to receive the developer image transferred from the photoconductor. The surface layer forms a contact inscribed angle &#x3b8; in the range of 10&#xb0; to 50&#xb0; between the surface thereof and the developer image. The image transfer member has a voltage-current characteristic exhibiting a current density (CD) in the range of 0.6 &#x3bc;A/cm&#x2266;CD&#x2266;1.5 &#x3bc;A/cmat 1 KV voltage, and a voltage decay characteristic exhibiting a voltage decay time (DT) in the range of 0.4 sec&#x2266;DT&#x2266;3 sec for the voltage decay from 500 V to 100 V. The present invention avoids a transfer defect such as transfer void produced by breakdown caused when a high bias voltage is applied to a developer image having a high electric charge and to significantly improve the transfer efficiency.

Growing community of inventors

Gwacheon-si, South Korea

Sang-don Lee