Patents by Inventor Chao Guan

Chao Guan 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: 20150090794
    Abstract: Method and system for correcting a QR code image is provided. An initial coordination system and a correction coordination system are determined at first. Conversion coefficients are obtained according to the coordinates of the central point of each detection pattern, the coordinates of the locating point in the initial coordinate system, the correction coordinate system. For each point in the correction coordinate system, its corresponding module in the initial coordinate system is found out, and the grayscale value of that module is assigned to the point to realize the correction of the QR code image. Coordinates of the three detection patterns, the locating point in the initial coordination system, and the correction coordinate system may be readily obtained according to different version numbers. At the same time, shortcomings caused by edge detection may be avoided, and a favorable correction effect may be obtained.
    Type: Application
    Filed: December 11, 2013
    Publication date: April 2, 2015
    Applicants: FOUNDER MOBILE MEDIA TECHNOLOGY (BEIJING) CO., LTD, PEKING UNIVERSITY FOUNDER GROUP CO., LTD.
    Inventors: Ling ZHANG, Chao Guan, Zhenhua Liu, Gezhang Liu, Wanyi Che
  • Publication number: 20150090795
    Abstract: Method and system for detecting detection patterns of a QR code is disclosed, detection is performed in a first direction and then in a second direction based on the first direction detection to detect a line segment having a length ratio of black:white:black:white:black meeting a predetermined ratio to determine the central points of the detection patterns, and thereby find out all detection patterns. Line-by-line traversal detection in a first direction is used to detect the detection patterns. Detection is performed based on the detected central point of the first line segment. Thus, detection steps may be greatly saved to simplify the detection procedure and improve computing speed. Fast detection of detection patterns may be realized for a QR code image.
    Type: Application
    Filed: December 11, 2013
    Publication date: April 2, 2015
    Applicants: FOUNDER MOBILE MEDIA TECHNOLOGY (BEIJING) CO., LTD., PEKING UNIVERSITY FOUNDER GROUP CO., LTD.
    Inventors: Ling Zhang, Chao Guan, Zhenhua Liu, Gezhang Liu, Wanyi Che
  • Publication number: 20150090792
    Abstract: Method and system for decoding a two dimensional code is disclosed. In the binarization process of a two dimensional code image, through performing a dividing operation on the two dimensional code image, each block region has a different grayscale threshold. For each block region, whether a pixel in the block region is determined as black or white is not solely based on the grayscale value of the pixel itself, but also an average grayscale value of a predetermined area set for the block region where the pixel locates. When the predetermined area in which the block region locates has a larger grayscale value as a whole, the grayscale threshold corresponding to the block region may become larger, and vice versa.
    Type: Application
    Filed: December 12, 2013
    Publication date: April 2, 2015
    Applicants: FOUNDER MOBILE MEDIA TECHNOLOGY (BEIJING) CO., LTD., PEKING UNIVERSITY FOUNDER GROUP CO., LTD.
    Inventors: Ling ZHANG, Chao Guan, Zhenhua Liu, Gezhang Liu, Wanyi Che
  • Patent number: 8598658
    Abstract: A high voltage lateral double diffused metal-oxide-semiconductor field effect transistor (LDMOS) comprises a substrate; an epitaxy layer on the substrate; a drift region on the epitaxy layer; and a drain region and a source region at two ends. At least one pair of n-type and p-type semiconductor regions is arranged alternately above the interface of the substrate and the epitaxy layer and firmly attached to a lower surface of the drifting region; the n-type and p-type semiconductor regions are firmly closed to each other and arranged to form a lateral PN junction; and the p-type semiconductor region and the drifting region form a vertical PN junction. The n-type and p-type semiconductor regions are also totally called “a reduced surface field (RESURF) layer in body”, and the LDMOS device with a RESURF layer in body effectively solves conflict between raising reverse withstand voltage and reducing forward on-resistance of the current LDMOS devices.
    Type: Grant
    Filed: April 28, 2011
    Date of Patent: December 3, 2013
    Assignee: University of Electronic Science and Technology of China
    Inventors: Jian Fang, Lvyun Chen, Wenchang Li, Chao Guan, Qiongle Wu, Wenbin Bo, Zehua Wang
  • Publication number: 20130214355
    Abstract: A high voltage lateral double diffused metal-oxide-semiconductor field effect transistor (LDMOS) comprises a substrate; an epitaxy layer on the substrate; a drift region on the epitaxy layer; and a drain region and a source region at two ends. At least one pair of n-type and p-type semiconductor regions is arranged alternately above the interface of the substrate and the epitaxy layer and firmly attached to a lower surface of the drifting region; the n-type and p-type semiconductor regions are firmly closed to each other and arranged to form a lateral PN junction; and the p-type semiconductor region and the drifting region form a vertical PN junction. The n-type and p-type semiconductor regions are also totally called “a reduced surface field (RESURF) layer in body”, and the LDMOS device with a RESURF layer in body effectively solves conflict between raising reverse withstand voltage and reducing forward on-resistance of the current LDMOS devices.
    Type: Application
    Filed: April 28, 2011
    Publication date: August 22, 2013
    Applicant: University of Electronic Science and Technology of China
    Inventors: Jian Fang, Lvyun Chen, Wenchang Li, Chao Guan, Qiongle Wu, Wenbin Bo, Zehua Wang