Multi-Dimensional, Non-Contact Metrology using Trilateration and High Resolution FMCW Ladar

• Main Authors: Mateo, Ana Baselga, Barber, Zeb W
• Format: Journal Article
• Language: English
• Published: 27-02-2015
• Subjects: Physics - Optics
• DOI: 10.48550/arxiv.1503.00042

Here we propose, describe, and provide experimental proof-of-concept
demonstrations of a multi-dimensional, non-contact length metrology system
design based on high resolution (millimeter to sub-100 micron) frequency
modulated continuous wave (FMCW) ladar and trilateration based on length
measurements from multiple, optical fiber-connected transmitters. With an
accurate FMCW ladar source, the trilateration based design provides 3D
resolution inherently independent of stand-off range and allows
self-calibration to provide flexible setup of a field system. A
proof-of-concept experimental demonstration was performed using a
highly-stabilized, 2 THz bandwidth chirped laser source, two emitters, and one
scanning emitter/receiver providing 1D surface profiles (2D metrology) of
diffuse targets. The measured coordinate precision of < 200 microns was
determined to be limited by laser speckle issues caused by diffuse scattering
of the targets.