Joyce Elaine Thompson

US Patent:

7641124, Jan 5, 2010

Filed:

Jun 30, 2006

Appl. No.:

11/479897

Inventors:

Kerry D. Brown - Portola Valley CA, US
David K. Pariseau - Los Altos CA, US
Weidong Li - Mountain View CA, US
Edgar M. Williams - Palo Alto CA, US
Joyce Thompson - Menlo Park CA, US

Assignee:

Qsecure, Inc. - Los Altos CA

International Classification:

G06K 19/06

US Classification:

235493, 235492, 235451

Abstract:

A Q-Chip MEMS magnetic device comprises a thin-film electronic circuit for implantation in the Track-2 area of a magnetic stripe on the back of a credit card. The Q-Chip MEMS magnetic device periodically self-generates new sub-sets of magnetic data that are to be read in combination with other magnetic data that is permanently recorded in the surrounding surface of the magnetic stripe. A collocated battery and microcontroller provide operating power and new data for magnetic bit updates. A swipe sensor triggers such updates by sensing electrical contact with a legacy card reader. Several thin-film coils of wire are wound end-to-end around a common, flat, ferrous core. These are driven by the microcontroller. In one instance, such core comprises “hard” magnetic material with a coercivity of 200-300 Oersteds. Magnetic data written from the corresponding adjacent coils will persist for later readings by a legacy card reader.

US Patent:

6721138, Apr 13, 2004

Filed:

Oct 24, 2001

Appl. No.:

09/999694

Inventors:

Yingjian Chen - Fremont CA
Xizeng Shi - Fremont CA
Hugh Craig Hiner - Fremont CA
Francis Liu - Fremont CA
Matthew R. Gibbons - Livermore CA
Joyce Anne Thompson - Menlo Park CA
William D. Jensen - Fremont CA
Chester Xiaowen Chien - San Jose CA
Yugang Wang - Milpitas CA

Assignee:

Western Digital (Fremont), Inc. - Fremont CA

International Classification:

G11B 539

US Classification:

360317, 360126

Abstract:

An inductive transducer having first and second magnetic pedestals disposed between first and second magnetic pole layers and adjacent to a media-facing surface, the pedestals separated by a submicron, nonmagnetic gap. The first pedestal extends less than the second pedestal from the media-facing surface, defining a short throat height. The second pedestal extends further to provide sufficient area for stitching to the second pole layer. The stitching and the thickness provided by the pedestals allow plural coil layers to be disposed between the pole layers, and the second pedestal, as well as other features, can be defined by high-resolution photolithography. The two coil layers have lower resistance, lower inductance and allow the pole layers to be shorter, improving performance. All or part of either or both of the pedestals may be formed of high magnetic saturation material, further enhancing performance.