Method and apparatus for asynchronous time measurement

US4908784A · kind A · utility

Assignee

• WAVE Technologies, Inc. · US

Inventors

• Gary William Box · Golden Valley, US
• Thomas S. Foote-Lennox · Bloomington, US
• Rodney G. Herreid · St. Louis Park, US
• James F. Hoff · Shoreview, US
• Dennis J. Leisz · Minnetonka, US
• John Albert Perlick · Eden Prairie, US
• Terry T. Steeden · Minneapolis, US
• John J. Turner · Calabasas, US
• Curtis R. Alexander · San Diego, US

Key dates

• Filing date: Aug 4, 1987
• Grant date: Mar 13, 1990
• Expiry date: Aug 4, 2007

Classification

• Technology area (CPC G): Physics
• CPC primary: G04F10/00
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The present invention relates to time measurement apparatus and method for measuring, with picosecond precision, intervals between single edged events, where each measured interval comprises the summation of a rough clock count and fine or calibrated vernier counts of measured fractional clock periods before and after each START and STOP event selected from a calibrated vernier memory. The calibrated vernier memory takes the form of a table of linear voltage versus time developed using pseudo-random generated measurement events of random duration and random separation.