Displacement measurements using phase changes

Details Displacement measurements using phase changes Displacement measurements using phase changes

2004-08-31

2009-10-27

Dang, Duy M (Department: 2624)

Image analysis

Applications

Range or distance measuring

C382S294000

Reexamination Certificate

active

07609858

ABSTRACT:
A measurement process or system transforms image data corresponding to images of an object to the frequency domain and analyzes the frequency domain data to determine a displacement of the object occurring between first and second images. Analysis in the frequency domain simplifies identification and handling of data expected to be noisy. In particular, frequencies corresponding to modes of vibration, lighting variation, or sensor error characteristic of a measurement system or frequencies corresponding to small magnitude frequency-domain data can be given little or no weighting in analysis that provides the displacement measurement. In one embodiment, Fourier transforms of shifted and unshifted images differ by a phase delay. A least square fit slope of the phase values associated with the phase delay can indicate displacements to accuracies less than 1% of a pixel width, thereby providing nanometer scale precision using imaging systems having a pixel width of about 1 μm.

REFERENCES:
patent: 5063524 (1991-11-01), Ferre et al.
patent: 5149980 (1992-09-01), Ertel et al.
patent: 5204739 (1993-04-01), Domenicali
patent: 6195475 (2001-02-01), Beausoleil, Jr. et al.
patent: 6628845 (2003-09-01), Stone et al.
patent: 2001/0053245 (2001-12-01), Sakai et al.
patent: 0480807 (1992-04-01), None
patent: 1061417 (2000-12-01), None
patent: WO 03/073367 (2003-09-01), None

Affiliated with

Also associated with

Rating

Displacement measurements using phase changes does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Displacement measurements using phase changes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Displacement measurements using phase changes will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-4130223