Patents by Inventor Chuan DU

Chuan DU has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20050053241
    Abstract: The method includes: associating different cell phones to different enciphering and deciphering keys of an asymmetric encryption algorithm. Access information of the network lock corresponding to the cell phone is enciphered by the corresponding enciphering key. Then, the enciphered network lock is stored in the cell phone, and the corresponding deciphering key is recorded in an inerasable memory of the cell phone. The original plaintext access information of the network lock and the enciphering key is stored only in a service provider of the communication network. When the cell phone tries to access the communication network, it deciphers the enciphered network lock using the deciphering key stored in the inerasable memory to verify the network lock of the cell phone.
    Type: Application
    Filed: April 2, 2004
    Publication date: March 10, 2005
    Inventors: Chen-Huang Fan, Ben-Chuan Du, Yi-Wen Cheng
  • Publication number: 20040185918
    Abstract: A method and related apparatus for reducing power consumption of a cell phone. The method includes: when the cell phone is in an idle state, connecting to a base station after a time interval several times that of the discrete receiving (DRX) time interval assigned by the base station so as to still maintain a logged-in state to the base station but to decrease radio transmissions and save power.
    Type: Application
    Filed: March 19, 2004
    Publication date: September 23, 2004
    Inventors: Chen-Huang Fan, Ben-Chuan Du
  • Publication number: 20040101129
    Abstract: The invention provides a device, used in a communication apparatus, for generating a mediate ring information and playing a ring signal based on the mediate ring information. The device comprises a receiving module, a processing module, an analyzing module, a storage module and a playing module. The receiving module receives an audio digital signal. The processing module divides the audio digital signal into a plurality of sub-signals in a predetermined period and then transfers the plurality of sub-signals into a plurality of sets of frequency spectrums. The analyzing module retrieves at least one frequency with largest amplitude in each of the plurality of sets of frequency spectrums respectively, and stores the retrieved frequencies in series to generate the mediate ring information. The storage module stores the mediate ring information and a plurality of predetermined tone information.
    Type: Application
    Filed: July 9, 2003
    Publication date: May 27, 2004
    Applicant: Benq Corporation
    Inventor: Ben-Chuan Du
  • Patent number: 6705699
    Abstract: An image output device includes two color ink cartridges. The first color ink cartridge is filled with yellow ink, magenta ink, and cyan ink. Besides, the yellow ink nozzle, first magenta ink nozzle, first cyan ink nozzle eject the yellow ink, magenta ink, and cyan ink respectively. The second color ink cartridge is filled with black ink, magenta ink, and cyan ink. Besides, the black ink nozzle, second magenta ink nozzle, and second cyan ink nozzle ejects the black ink, magenta ink, and cyan ink respectively. The second magenta ink nozzle has a diameter smaller that of the first magenta ink nozzle, and the second cyan ink nozzle has a diameter smaller that of the first cyan ink nozzle. The color ink cartridge ink having the nozzle with small diameter is driven to create small ink drops or light ink drops. It improves the image resolution and creates a six-color tone expression. Moreover, the cost of manufacturing the printhead will not increase and the controlling method will not become complicated.
    Type: Grant
    Filed: May 1, 2002
    Date of Patent: March 16, 2004
    Assignee: Benq Corporation
    Inventors: Ben-Chuan Du, Yung-Yi Li
  • Publication number: 20040013269
    Abstract: The invention provides a device, used in a communication apparatus including a cipher-key generating module, for securing a subscriber's information. The device includes a storage module, a cipher-key acquiring module, an encrypting module and a decrypting module. The subscriber's information is stored in the storage module. The cipher-key acquiring module transmits an input to the cipher-key generating module, and then receives a cipher key generated by the cipher-key generating module in response to the input. The encrypting module retrieves the cipher key through the cipher-key acquiring module, retrieves the subscriber's information from the storage module, and encrypts the subscriber's information using the cipher key to generate an encrypted information. After generated, the encrypted information is stored into the storage module and replaces the subscriber's information.
    Type: Application
    Filed: July 10, 2003
    Publication date: January 22, 2004
    Applicant: BENQ CORPORATION
    Inventors: Ben-Chuan Du, Chen-Huang Fan
  • Patent number: 6679577
    Abstract: A method of performing printhead maintenance comprises the steps as follow. First, the orifices of the printhead are defined to form a plurality of orifice groups. Then, a test graph comprising a plurality of test lines associated with the orifice groups is provided, and the ink is ejected through the printhead to obtain a printing result of the test graph. Next, the orifice groups containing the clogged orifices are selected according to the printing result. Then the orifice groups to be cleaned undergo the maintenance procedure. In the present invention, the orifice groups to be cleaned are determined by comparing the printing result and the test graph. Then the maintenance procedure can be selected to purge only the orifice groups containing clogged orifices, so that the unnecessary consumption of ink in purging unclogged orifices is reduced.
    Type: Grant
    Filed: February 11, 2002
    Date of Patent: January 20, 2004
    Assignee: Benq Corporation
    Inventors: Ben-Chuan Du, Yung-Yi Li
  • Publication number: 20030109243
    Abstract: A portable electronic device with power failure recovery, powered by a main power source, the device comprising a power detection module, a processor, a timing unit and a power management unit. The power detection module detects an output characteristic from the main power source and asserts an interrupt signal if the characteristic is below a threshold value. The processor asserts a turn-off signal and an enable signal in response to the interrupt signal. The timing unit asserts a notification signal at a predetermined time interval when the enable signal is asserted. Upon receipt of the turn-off signal, the power management unit disconnects the main power source to a circuit block with high power consumption. Moreover, the power management unit reconnects the main power source to the circuit block when the notification signal is asserted and the output characteristic of the main power source is beyond the threshold value.
    Type: Application
    Filed: December 7, 2001
    Publication date: June 12, 2003
    Applicant: Acer Communications and Multimedia Inc.
    Inventors: Hsin-Chin Chang, Chen-Huang Fan, Ben-Chuan Du
  • Publication number: 20020163557
    Abstract: An image output device includes two color ink cartridges. The first color ink cartridge is filled with yellow ink, magenta ink, and cyan ink. Besides, the yellow ink nozzle, first magenta ink nozzle, first cyan ink nozzle eject the yellow ink, magenta ink, and cyan ink respectively. The second color ink cartridge is filled with black ink, magenta ink, and cyan ink. Besides, the black ink nozzle, second magenta ink nozzle, and second cyan ink nozzle ejects the black ink, magenta ink, and cyan ink respectively. The second magenta ink nozzle has a diameter smaller that of the first magenta ink nozzle, and the second cyan ink nozzle has a diameter smaller that of the first cyan ink nozzle. The color ink cartridge ink having the nozzle with small diameter is driven to create small ink drops or light ink drops. It improves the image resolution and creates a six-color tone expression. Moreover, the cost of manufacturing the printhead will not increase and the controlling method will not become complicated.
    Type: Application
    Filed: May 1, 2002
    Publication date: November 7, 2002
    Inventors: Ben-Chuan Du, Yung-Yi Li
  • Publication number: 20020149641
    Abstract: A method of performing printhead maintenance comprises the steps as follow. First, the orifices of the printhead are defined to form a plurality of orifice groups. Then, a test graph comprising a plurality of test lines associated with the orifice groups is provided, and the ink is ejected through the printhead to obtain a printing result of the test graph. Next, the orifice groups containing the clogged orifices are selected according to the printing result. Then the orifice groups to be cleaned undergo the maintenance procedure. In the present invention, the orifice groups to be cleaned are determined by comparing the printing result and the test graph. Then the maintenance procedure can be selected to purge only the orifice groups containing clogged orifices, so that the unnecessary consumption of ink in purging unclogged orifices is reduced.
    Type: Application
    Filed: February 11, 2002
    Publication date: October 17, 2002
    Inventors: Ben-Chuan Du, Yung-Yi Li
  • Publication number: 20020118239
    Abstract: The present invention is related to an apparatus and a method for improving the quality of printing. The reference timings are adjusted by random values to decrease the cyclic unevenness of images associated with the conventional technique. The random values may be generated by the apparatus itself or may be received from an external device, such as a personal computer. The distance between two adjacent dots changes, and the unevenness of images is scattered to provide a higher quality of printing.
    Type: Application
    Filed: February 26, 2002
    Publication date: August 29, 2002
    Applicant: Benq Corporation
    Inventors: Ben-Chuan Du, Yung-Li Li
  • Patent number: 6416147
    Abstract: A printer has a print path disposed along a left-and-right direction, a driving system for moving a print head left or right along the print path, a control circuit for controlling the driving system, and a look-ahead system. The print head is used to perform a printing operation that forms at least one pixel on a media in a print swath. The look-ahead system determines a plurality of different paths that cover at least three print swaths, and computes a print time required by the driving system to cover each path. The look-ahead system then selects a path having the shortest print time, and the control system directs the driving system to follow this path.
    Type: Grant
    Filed: December 21, 2000
    Date of Patent: July 9, 2002
    Assignee: Acer Communications and Multimedia Inc.
    Inventors: Yung-Yi Li, Ben-Chuan Du
  • Patent number: 6416148
    Abstract: A printer has a print head for forming a pixel, and a driving system for moving the print head from a first location to a second location. The print head forms the pixel according to a firing signal. The movement of the print head is controlled by a control signal sent to the driving system. The method involves building a list of desired pixel locations, building a calibrated list of firing signal offsets, sending the control signal to trigger movement of the print head, and sending a firing signal to the print head to form a pixel at a predetermined location. The firing signal offsets correspond to the desired pixel locations, and are adjusted to compensate for the driving system. The timing of the firing signal is determined by the timing of the control signal and by a firing signal offset in the calibrated list of firing signal offsets. The firing signal offset adjusts the firing time so that the predetermined location of the pixel is effectively on a corresponding desired pixel location.
    Type: Grant
    Filed: January 5, 2001
    Date of Patent: July 9, 2002
    Assignee: Acer Communications and Multimedia Inc.
    Inventors: Ben-Chuan Du, Yung-Yi Li
  • Publication number: 20020080201
    Abstract: A printer has a print path disposed along a left-and-right direction, a driving system for moving a print head left or right along the print path, a control circuit for controlling the driving system, and a look-ahead system. The print head is used to perform a printing operation that forms at least one pixel on a media in a print swath. The look-ahead system determines a plurality of different paths that cover at least three print swaths, and computes a print time required by the driving system to cover each path. The look-ahead system then selects a path having the shortest print time, and the control system directs the driving system to follow this path.
    Type: Application
    Filed: December 21, 2000
    Publication date: June 27, 2002
    Inventors: Yung-Yi Li, Ben-Chuan Du
  • Patent number: 6371593
    Abstract: A printer has a print path, a code strip disposed in parallel along the print path, a sensor for sensing the code strip, a driving system for moving the sensor along the code strip, a timer, a memory and a position signal generator. The code strip has embedded position information, which the sensor reads. The sensor generates a first or a second code signal depending upon the position of the sensor on the code strip. The timer generates clock signals at a rate that corresponds to an expected rate of change of the first and second signals from the sensor when the driving system moves the sensor along the code strip. The memory is used to hold the locations of defective areas on the code strip. The position signal generator uses the sensor to generate a position signal when the sensor is not reading within any of the defective areas on the code strip, and uses the clock signals from the timer to generate the position signal when the sensor is moving within any of the defective areas on the code strip.
    Type: Grant
    Filed: January 5, 2001
    Date of Patent: April 16, 2002
    Assignee: Acer Communication and Multimedia Inc.
    Inventors: Yung-Yi Li, Ben-Chuan Du