John M Widder

US Patent:

7995217, Aug 9, 2011

Filed:

Oct 14, 2008

Appl. No.:

12/287845

Inventors:

John A. Widder - Washougal WA, US

Assignee:

STMicroelectronics, Inc. - Coppell TX

International Classification:

G01B 11/14
G06F 15/00

US Classification:

356614, 702150, 702158

Abstract:

A position sensing apparatus and method, motion control system, and integrated circuit are provided that include a plurality of sensors and a tracking processor. The plurality of sensors includes a linear array of sensors that sense a plurality of features of an object. A spacing between two of the plurality of sensors is substantially smaller than a spacing between two of the plurality of features. The tracking processor samples signals from the sensors, compares the samples to previous samples and calculates a position of the object. The plurality of sensors may include a second linear array of sensors. Centers of the sensors of the second linear array may be offset from centers of the sensors of the first linear array along a longitudinal axis of the plurality of sensors.

US Patent:

56466544, Jul 8, 1997

Filed:

Mar 9, 1995

Appl. No.:

8/401393

Inventors:

John A. Widder - Camas WA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

B41J 2938
B41J 29393

US Classification:

347 14

Abstract:

An ink-jet printing system includes an ink-jet print head having multiple nozzles for ejecting drops of ink onto the recording media to form printed images. The ink-jet print head emits an audible sound during the ejection of an ink droplet, but remains comparatively silent when no ink droplet is ejected. An acoustic detector is provided to detect the audible sound emitted by the ink-jet print head during ejection of the ink droplet. The system further includes an energy control subsystem coupled to supply pulses of operating energy to the print head to cause ejection of the ink droplets. The energy control subsystem is operatively coupled to receive feed back information from the acoustic detector which is then used to adjust the operating energy pulses that are supplied to the print head. The energy control subsystem adjusts the operating energy pulses in a manner that causes the print head to emit audible sounds that are optimized toward approximating an ideal audible sound indicative of optimal operation.

US Patent:

54754054, Dec 12, 1995

Filed:

Dec 14, 1993

Appl. No.:

8/167595

Inventors:

John A. Widder - Portland OR
Peter C. Nicholson - Vancouver WA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

B41J 205

US Classification:

347 14

Abstract:

A temperature control circuit regulates temperature in an ink-jet print head. The control circuit includes a thermal sensor mounted on the print head to measure its temperature and a temperature level detector to determine whether the measured print head temperature exceeds a threshold temperature. The temperature level detector outputs a first signal when the measured print head temperature exceeds the threshold temperature and a second signal when the measured print head temperature does not exceed the threshold temperature. The control circuit also has first logic circuitry to output warming pulses upon receipt of the second signal. The warming pulses have energy insufficient to deposit an ink drop from the print head. Second logic circuitry is configured to output warming pulses to non-selected nozzles of the print head and firing pulses to selected nozzles. In this manner, the print head is automatically warmed via the warming pulses so long as the print head temperature is below a prescribed level.