06879403 is referenced by 29 patents and cites 18 patents.

A system for measuring the spatial dimensions of a three-dimensional object employs a lens and at least two detectors. The combination of which defines two or more object planes. The combination of the lens and the detectors define an optical axis that is normal to the object planes and passes through a focal point of the lens. At least a first and a second photodetector are optically aligned with the object through the lens. The first and second photodetectors or array of detectors are further parallel with the surface but have differing elevations relative to that surface. In addition, the first and second photodetectors are capable of motion relative to said object. Electrical output from the first and from the second photodetectors is provided to a processor that determines a distance of the object from the lens and thereby a height of the object. This system is particularly suited for measuring the spatial dimensions of solder balls mounted to a surface of a ball grid array (BGA) electronic package.

Title
Three dimensional scanning camera
Application Number
10/800319
Publication Number
6879403 (B2)
Application Date
March 11, 2004
Publication Date
April 12, 2005
Inventor
Daniel Freifeld
Napa
CA, US
Agent
Gregory S Rosenblatt
Anthony P Gangemi
Wiggin and Dana
Assignee
Visicon Inspection Technologies
CA, US
IPC
G01B 011/24
View Original Source