Abstract: An optical disc of write once type, a method and an apparatus of managing defect information on the optical disc of write once type, e.g., a BD-WO, are provided with a temporary defect management area (TDMA). The method includes preparing the temporary defect management area (TDMA) in which a temporary defect list (TDFL) is recorded as defect management information for managing a defective area on the optical disc, recording the most recent temporary defect list cumulatively with the previous temporary defect list in the temporary defect management area, and recording position information for indicating a position of the most recent temporary defect list in the temporary defect management area along with the temporary defect list to more effectively manage the temporary defect list.

Abstract: A write-once type optical disc and a method and apparatus for allocating a spare area on the write-once type optical disc are provided. The method includes allocating a data area on a recording medium of write-once type, and allocating a user data area and at least one spare area within the data area on the recording medium, the at least one spare area having a variable size, wherein a maximum recording capacity of the at least one spare area on the recording medium is less than a maximum recording capacity of at least one variable spare area on a rewritable type optical disc.

Abstract: A rotary force controlling apparatus and an image forming apparatus including the same are provided. The rotary force controlling apparatus includes a clutch device having a shaft, and a rotary body mounted at one end of the shaft. A housing receives and rotates together with the shaft. A power transferring member is rotatably mounted in the housing and selectively rotates the housing by a clutch inserted between the housing and the power transferring member. A positioning unit protrudes from the periphery of the housing and positions a stop location of the rotary body. A solenoid unit is spaced apart from the clutch device and is selectively turned on and off. The positioning unit includes a first positioning unit that positions an initial location of the rotary body when the solenoid unit is turned on; and a plurality of second positioning units that are separated from the first positioning unit and stop the rotary body at a predetermined location when the solenoid unit is turned off.

Abstract: An image forming apparatus is configured to reduce a velocity fluctuation of a rotating body by reducing the AC velocity component of the rotating body. The image forming apparatus may include an image bearing body with a surface on which a toner image is formed; a driving motor configured to drive the image bearing body according to an input signal; and a controller configured to control the driving motor to output a motor output velocity at a period equal to that of an AC velocity component of the image bearing body. A velocity control method for the rotating body includes sampling a continuous motor input signal at a period equal to that of an AC velocity component of a rotating velocity of the rotating body. The sampled signal is transmitted to a driving motor that drives the rotating body, which is driven based upon the discrete motor input signal.

Abstract: A recording medium, and a method and apparatus for recording management information on the recording medium are discussed. According to an embodiment, the invention provides a method of recording management information on a recording medium, the recording medium including a temporary defect management area (TDMA) and a final defect management area (DMA), the DMA including a defect list area, the method comprising: recording, in the TDMA, defect list information produced while the recording medium is in use, and recording, in the defect list area of the DMA, the latest defect list information included in the TDMA when the recording medium is to be finalized, wherein the defect list area of the DMA includes a plurality of recording units, and the latest defect list information is recorded on at least one of the recording units of the defect list area.

Abstract: A method and device for managing a recording medium including a non data area having a final defect management area and a data area having a user data area and a spare area. The method includes: (a) recording a defect list onto one or more recording-units of a temporary defect management area allocated to one of the non data area and the spare area, and recording position information of the defect list onto the temporary defect management area, the position information containing one or more defect list pointers which indicate position of the one or more recording-units containing the defect list; and (b) if a recoding-unit is defective, re-recording defect list data onto another recording-unit, and recording updated position information containing a defect list pointer indicating a position of the another recording-unit instead of a defect list pointer indicating a position of the defective recording-unit.

Abstract: A high voltage switch device includes a plurality of switches installed between a high voltage power unit and a plurality of developing units. A plurality of cams are disposed on a cam shaft corresponding to the respective switches. The switches are selectively turned “on” and “off” as the cam shaft rotates.

Abstract: A write-once optical recording medium, a method for allocating a defect management area of the write-once optical recording medium, and a method for allocating a spare area of the write-once optical recording medium are provided. A method of managing defects on a write-once optical recording medium having at least one recording layer includes the steps of allocating at least one temporary defect management area having a fixed size and at least one temporary defect management area having a variable size to said optical recording medium, respectively, recording defect management information on the at least one temporary defect management area having a fixed size and the at least one temporary defect management area having a variable size; and using the at least one temporary defect management area having a fixed size and the at least one temporary defect management area having a variable size is provided herein.

Abstract: The data structure on the recording medium includes a temporary defect management area storing a data block. The data block includes a space bit map and a temporary definition structure. The space bit map indicates recordation status of the data area, and the temporary definition structure provides a pointer to the space bit map.

Abstract: A method and apparatus for managing a defective area on a optical recording medium, e.g., of writable once type, permits more efficient writing and management of defect list information or temporary defect list information for managing the defective area in a minimum recording size. The method includes writing data in a defective area existing on a high density optical disc, e.g., such as a BD-WO, in a spare area in place of the defective area, producing defect list information for access to the data replacement written in the spare area and writing in a particular area for defect management. The defect entries actually corresponding to the replacement written data, and writing location information of the next available spare area are written and managed as defect list information for management, or the writing location information of a location where replacement writing is possible is written and managed as defect definition structure information.

Abstract: A device and method of reproducing and/or recording data onto a write once recording medium, the recording medium having a data area and a management area, the data area having a spare area. The recording method include: performing a replacement-recording by recording data requested to be recorded in a specified area onto a replacement area in the data area when the specified area is defective or contains data recorded thereon; and recording onto the management area a pair of consecutive entries for managing the replacement-recording when a size of the specified area corresponds to a plurality of consecutive recording-units. One of the pair of consecutive entries includes start address information of the specified area and start address information of the replacement area and another of the pair of consecutive entries includes end address information of the specified area and end address information of the replacement area.

Abstract: A method of managing overwrite and a method of recording management information on an optical disc write once can make it possible to perform a logical overwrite on the disc and thus heighten the use efficiency of the disc. The method includes replacement-recording data which is requested to be overwritten in a specified area of the disc where recording is completed in another data area physically separated from the specified area in the disc, and producing and recording management information for reproducing the physically replacement-recorded data.

Abstract: A write-once optical recording medium, a method for allocating a defect management area of the write-once optical recording medium, and a method for allocating a spare area of the write-once optical recording medium are provided. A method of managing defects on a write-once optical recording medium having at least one recording layer includes the steps of allocating at least one temporary defect management area having a fixed size and at least one temporary defect management area having a variable size to said optical recording medium, respectively, recording defect management information on the at least one temporary defect management area having a fixed size and the at least one temporary defect management area having a variable size; and using the at least one temporary defect management area having a fixed size and the at least one temporary defect management area having a variable size is provided herein.

Abstract: Disclosed herein is a wireless device including at least one locker structure. The locker structure includes a battery pack side coupling member (a first coupling member) protruding from the outer surface of a battery pack, the first coupling member having a hook formed at one side thereof and a structure tapered downward toward the battery pack (an incline structure) at the other side thereof, and a wireless device body side coupling member (a second coupling member) mounted in a body of the wireless device at the position corresponding to the first coupling member, the second coupling member including a coupling part which can be coupled with the hook, a member body having a rear protrusion formed at the position corresponding to the incline, and an elastic member mounted at the rear of the member body.

Abstract: A defective area on a write-once type optical recording medium, e.g., such as a BD-WO, is effectively managed with a method that can efficiently replace and/or record data that has been recorded in a defective area of the disc, e.g., in a spare area of a data area of the BD-WO. During the reproduction of data, the data that has been recorded and replaced can be read out and reproduced from an area other than a spare area. New TDFL information may be recorded cumulatively with the previous TDFL information as defect management information for the defective area, or repeatedly recorded at least twice in a certain recording region, e.g., a recording region chosen from a lead-in area, the data area, and a lead-out area, so that the temporary defect list information can be accurately and reliably secured.

Abstract: A writable-once optical recording medium such as a BD-WO, and a method and apparatus for managing the writable-once optical recording medium, are provided. According to an embodiment, the method includes recording temporary management information in a temporary defect management area of the recording medium, the temporary management information including disc usage management information indicating a recording or non-recording status of the user area of the each recording layer; and transferring the disc usage management information from the at least one temporary defect management area to the at least one final defect management area of the recording medium, wherein in the recording step, the disc usage management information for each of the recording layers is separately recorded in the temporary defect management area.

Abstract: A method and apparatus for managing a defective area of a recording medium, are discussed. According to an embodiment, the method includes identifying a finalization state by searching identification information indicating whether or not the recording medium is finalized; searching a location of defect list information recorded in a management area when identification information indicating the recording medium is finalized; and searching a location of latest temporary defect list information recorded in a temporary management area when identification information indicating the recording medium is not finalized.

Abstract: A developing device driver according to the present invention includes a developing roller gear connected to each developing roller to develop an electrostatic latent image formed on a photoconductive medium with developer having predetermined color, a driving source for generating power for rotating the developing roller gear, a driving gear driven by the power transmitted from the driving source, and a power switching gear provided with power from the driving gear and rotated along a circumference of the driving gear, and a rotation unit. The rotation unit rotates the power switching gear to place the power switching gear into contact with and separate the gear from the developing roller gears to selectively drive one developing roller.

Abstract: Provided is an image forming apparatus for printing a desired image.

Abstract: A method and apparatus for recording or reproducing data are discussed. According to an embodiment, the invention is directed to a method for recording data onto a recording medium having a recording layer, the recording layer including an inner area, a data area and an outer area, the data area having a user data area and a spare area, the user data area consisting of a plurality of clusters, the method comprising steps of: (a) recording a first data block having a temporary defect list for managing a defective area of the data area onto a temporary defect management area allocated in the inner area or the spare area; and (b) recording a second data block having a space bitmap onto the temporary defect management area.