04357672 is referenced by 36 patents and cites 11 patents.

The disclosure is directed to a microprocessor-based apparatus and method for determining the distance between an object and a reference position. An embodiment of a graphical digitizer is set forth in which a microprocessor system is adapted to generate and store a count that depends upon the number of instruction cycles that the microprocessor system performs during a time interval that is a function of the travel time of acoustic wave energy traveling between the object and the reference position. In a disclosed embodiment, acoustic receivers are mounted with their axes parallel, and each receiver has a generally circular receptivity pattern.

Title
Distance ranging apparatus and method
Application Number
6/173723
Publication Number
4357672
Application Date
July 30, 1980
Publication Date
November 2, 1982
Inventor
Seymour J Sindeband
Pound Ridge
NY, US
Joseph A Howells
Brookfield Center
CT, US
Agent
Martin Novack
Assignee
Science Accessories Corporation
CT, US
IPC
G06F 15/20
View Original Source