Philip A Chang

US Patent:

D471247, Mar 4, 2003

Filed:

Apr 1, 2002

Appl. No.:

29/158108

Inventors:

Philip Chang - Foster City CA

Assignee:

Montgomery Golf Corporation - Foster City CA

International Classification:

2102

US Classification:

D21789

US Patent:

6647185, Nov 11, 2003

Filed:

Feb 12, 2002

Appl. No.:

10/076020

Inventors:

Roger A. Hajjar - San Jose CA
John M. Beley - Moorpark CA
Philip Chang - San Jose CA

Assignee:

Vitesse Semiconductor Corporation - San Jose CA

International Classification:

G02B 642

US Classification:

385 48, 385 2, 385 14, 385 40

Abstract:

Techniques for optically sampling the output of a Mach-Zehnder electro-optic modulator without interfering the output optical signal.

US Patent:

D4379098, Feb 20, 2001

Filed:

Jun 9, 2000

Appl. No.:

D/124743

Inventors:

Philip L. Chang - Sunnyvale CA

Assignee:

Swing Solutions - Sunnyvale CA

International Classification:

2102

US Classification:

D21789

US Patent:

D4376269, Feb 13, 2001

Filed:

Jul 19, 1999

Appl. No.:

D/107933

Inventors:

Philip L. Chang - Sunnyvale CA

Assignee:

Swing Solutions - Sunnyvale CA

International Classification:

2102

US Classification:

D21796

US Patent:

53420543, Aug 30, 1994

Filed:

Mar 25, 1993

Appl. No.:

8/037089

Inventors:

Philip L. Chang - San Bruno CA
Gary S. Flood - Saratoga CA
Kent W. Kirkes - Palo Alto CA
Edwin R. Smith - San Jose CA

Assignee:

Timecap, Inc. - Sunnyvale CA

International Classification:

G06F 1544

US Classification:

2731861

Abstract:

A golf practice apparatus provides recording and instant playback of video images of a golfer's swing. A plurality of color video cameras are preferably employed to obtain video images of a swing from different angles. A video processing and storage unit digitally stores the images in memory for instant replay. Image processing and recording is automatically initiated when a golf ball is placed on a designated hitting area through the use of an infrared camera and image processing software that detects a golf ball in the IR camera's image. The IR camera is also used in conjunction with an IR flash unit to obtain snapshot images of a club head and ball just before and just after the golf club hits the ball. An optical sensor array is positioned adjacent the hitting area to detect the passage of a golf club toward the ball. The signals generated by the optical sensor array are employed by the image processing and storage unit to both calculate the club speed and control triggering of the flash unit.