Patents by Inventor Keng-Hao Chang

Keng-Hao Chang 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: 20150063430
    Abstract: The present invention provides a transceiver for a radio frequency identification (RFID) reader. The transceiver includes an RF front end, a transmitting component, a receiving component, a power divider and a micro control unit (MCU). The power divider has three terminals. The first terminal of the power divider is connected to the transmitting component. The second terminal of the power divider is connected to the receiving component. The third terminal is connected to the RF front end. Moreover, the MCU is connected to the transmitting component and the receiving component, and generates a transmitted signal and receives a retrieved data. According to the present invention, the transceiver further includes an RF switch, a matching circuit and a receiving circuit.
    Type: Application
    Filed: August 27, 2014
    Publication date: March 5, 2015
    Inventors: Keng-Hao CHANG, Shao-Chang CHANG
  • Patent number: 8803681
    Abstract: A receiver of an object finder includes an antenna to receive a signal from a transmitter associated with the receiver, a PIN diode having a first terminal coupled with the antenna, and having a resistance that increases as a current flows therethrough decreases, and vice versa, a variable resistor coupled with the first terminal of the PIN diode to control the amount of a current flowing into the PIN diode, and a radio frequency integrated circuit (RF IC) having a first pin electrically coupled with second terminal of the PIN diode to receive the signal from the antenna via the PIN diode.
    Type: Grant
    Filed: September 9, 2011
    Date of Patent: August 12, 2014
    Assignee: FAVEPC Inc.
    Inventors: Hung-Cheng Chen, Keng-Hao Chang
  • Patent number: 8505819
    Abstract: The present invention discloses a biological measuring device with auto coding capabilities. In accordance with one embodiment of the present invention, the biological measuring device with auto coding capabilities includes a test strip having a substrate and at least a first contact pad and a second contact pad provided on the substrate; and a code reader having at least a first metal pin and a second metal pin to couple to the first contact pad and the second contact pad to obtain coding information associated with the test strip, wherein the code reader is capable of reading the coding information based on a movement of the test strip before the test strip is placed still in relation to the code reader for a proper reading of a sample.
    Type: Grant
    Filed: October 26, 2011
    Date of Patent: August 13, 2013
    Assignee: Tyson Bioresearch, Inc.
    Inventors: Cheng-Che Lee, Wen-Hai Tsai, Keng-Hao Chang, Chiu-Chin Yang, Waken Chen, Jih-Hsin Yeh
  • Publication number: 20130122532
    Abstract: The present invention discloses a biological measuring device with auto coding capabilities. In accordance with one embodiment of the present invention, the biological measuring device with auto coding capabilities may include a test strip associated with a code pattern; and a code reader electrically coupled to the test strip to read the code pattern, wherein the code reader is configured to read an output from the code pattern consisted of a first logical value, a second logical value, and a third logical value.
    Type: Application
    Filed: November 14, 2011
    Publication date: May 16, 2013
    Inventors: Tsung-Sung Hsiao, Wen-Huang Chen, Keng-Hao Chang, Han-Ching Tsai
  • Patent number: 8421895
    Abstract: An image sensing device and image sensing method is described, in which an interrupt circuit is disposed to interrupt a clock signal input to a logic circuit not associated with the reading of image data when the image data is read, so as to temporarily interrupt the operation of the logic circuit, thereby reducing the power noises caused by the current generated during the operation of the logic circuit.
    Type: Grant
    Filed: March 5, 2012
    Date of Patent: April 16, 2013
    Assignee: Pixart Imaging Inc.
    Inventors: Le-Chun Ho, Wen-Cheng Yen, Keng-Hao Chang
  • Publication number: 20130063261
    Abstract: A receiver of an object finder includes an antenna to receive a signal from a transmitter associated with the receiver, a PIN diode having a first terminal coupled with the antenna, and having a resistance that increases as a current flows therethrough decreases, and vice versa, a variable resistor coupled with the first terminal of the PIN diode to control the amount of a current flowing into the PIN diode, and a radio frequency integrated circuit (RF IC) having a first pin electrically coupled with second terminal of the PIN diode to receive the signal from the antenna via the PIN diode.
    Type: Application
    Filed: September 9, 2011
    Publication date: March 14, 2013
    Inventors: Hung-Cheng Chen, Keng-Hao Chang
  • Publication number: 20120104096
    Abstract: The present invention discloses a biological measuring device with auto coding capabilities. In accordance with one embodiment of the present invention, the biological measuring device with auto coding capabilities includes a test strip having a substrate and at least a first contact pad and a second contact pad provided on the substrate; and a code reader having at least a first metal pin and a second metal pin to couple to the first contact pad and the second contact pad to obtain coding information associated with the test strip, wherein the code reader is capable of reading the coding information based on a movement of the test strip before the test strip is placed still in relation to the code reader for a proper reading of a sample.
    Type: Application
    Filed: October 26, 2011
    Publication date: May 3, 2012
    Inventors: Cheng-Che Lee, Wen-Hai Tsai, Keng-Hao Chang, Chiu-Chin Yang, Waken Chen, Jih-Hsin Yeh
  • Patent number: 8164667
    Abstract: An image sensing device and image sensing method is described, in which an interrupt circuit is disposed to interrupt a clock signal input to a logic circuit not associated with the reading of image data when the image data is read, so as to temporarily interrupt the operation of the logic circuit, thereby reducing the power noises caused by the current generated during the operation of the logic circuit.
    Type: Grant
    Filed: May 8, 2009
    Date of Patent: April 24, 2012
    Assignee: Pixart Imaging Inc.
    Inventors: Le-Chun Ho, Wen-Cheng Yen, Keng-Hao Chang
  • Publication number: 20100294660
    Abstract: The present invention provides an electrochemical biosensor. The biosensor includes a substrate; a metal layer disposed on the substrate, wherein a first end of the metal layer is formed with a reaction region by a working electrode and a reference electrode provided on the metal layer, the reaction region is applied with an enzyme so that an electrical response is generated when the enzyme and a test sample form a chemical reaction, and a second end of the metal layer is provided with an integrated information unit to provide both test sample information and coding information.
    Type: Application
    Filed: March 12, 2010
    Publication date: November 25, 2010
    Inventors: Shiow-Chen Wang, Wen Hai Tsai, Jih-Hsin Yeh, Chia Jung Chen, Hung Chih Lin, Keng Hao Chang, Yi-Chi Yang
  • Publication number: 20100283877
    Abstract: An image sensing device and image sensing method is described, in which an interrupt circuit is disposed to interrupt a clock signal input to a logic circuit not associated with the reading of image data when the image data is read, so as to temporarily interrupt the operation of the logic circuit, thereby reducing the power noises caused by the current generated during the operation of the logic circuit.
    Type: Application
    Filed: May 8, 2009
    Publication date: November 11, 2010
    Applicant: PixArt Imaging Inc.
    Inventors: Le-Chun Ho, Wen-Cheng Yen, Keng-Hao Chang
  • Publication number: 20100208566
    Abstract: The invention provides a method for performing layer changes for an optical disk drive. In one embodiment, the optical disk drive intends to move a focus of a laserbeam emitted by a pickup head from a present layer onto a target layer of an optical disk. First, an amplitude ratio between a first amplitude of a first S-curve of a previous focusing error signal and a second amplitude of a second S-curve of the previous focusing error signal is determined. The object lens is then moved towards a target position for focusing of the laserbeam on the target layer. A focusing error signal is then generated. The focusing error signal is then amplified or attenuated according to the amplitude ratio to obtain an amplified or attenuated focusing error signal. Whether the object lens has reached the target position is then determined according to the amplified or attenuated focusing error signal.
    Type: Application
    Filed: February 18, 2009
    Publication date: August 19, 2010
    Applicant: MEDIATEK INC.
    Inventors: Keng-Hao Chang, Jyh-Haur Chen
  • Publication number: 20070229743
    Abstract: An alignment method is described. First, an alignment layer material disposed on a substrate is provided. Then, a rubbing medium disposed on a surface of an alignment roller is provided, and the surface of the alignment roller is at a distance from the surface of the alignment layer material. The rubbing medium is used to align the alignment layer material, and the alignment roller is suitable for being driven by a torque and maintaining a particular rotating speed. There is a rate between the distance and the torque. When the torque of the alignment roller is larger or smaller than the range, the distance corresponding to the torque is calculated based on the rate. A distance difference value is deduced from the distance corresponding to the torque. Then, the distance is adjusted with the distance difference value.
    Type: Application
    Filed: April 4, 2006
    Publication date: October 4, 2007
    Inventors: Chein-Wen Chen, Hong-Wen Chuang, Keng-Hao Chang, Wen-Jhy Lin
  • Publication number: 20060119313
    Abstract: A Bluetooth GPS receiver with a solar panel includes an electric circuit board and a solar panel positioned on and electrically connected with the electric circuit board. Then the solar panel together with the electric circuit board is deposited between an upper shell and a lower shell of the receiver. The upper shell is further provided with a transparent board just on the solar panel to let sunlight shine on the solar panel through the transparent board, so the solar panel may absorb and convert solar energy into electricity to be used directly by the receiver and also to charge a rechargeable battery placed in the lower shell, Then the battery may supply the receiver with electricity when there is no sunlight, and for a long period of time.
    Type: Application
    Filed: December 1, 2005
    Publication date: June 8, 2006
    Inventor: Keng-Hao Chang
  • Patent number: 5813317
    Abstract: A brewing pot for tea includes a container including an upper portion having a top rim defining at least one cavity, and a lower portion defining a chamber, and an abutting edge formed between the upper portion and the lower portion. A supporting base supported on the abutting edge includes an upright post. A cylindrical body is slidably mounted on the supporting base and includes a top portion formed with an annular flange and a bottom portion defining a socket. At least one block is formed on the annular flange and abuts on the top rim of the container, and a control ball is received in the socket. The cylindrical body and the supporting base can be rotated relative to the container to a position where the block is received in the cavity such that the body can be moved downward relative to the supporting base while the control ball can be moved toward the post such that the control ball can be urged by the post to rise from the socket.
    Type: Grant
    Filed: December 15, 1997
    Date of Patent: September 29, 1998
    Inventor: Keng-Hao Chang