We describe a high accuracy frequency stepping method for a tunable diode laser to improve a three dimensional (3D) imaging approach based upon interferometric speckle imaging. The approach, modeled after Takeda, exploits tuning an illumination laser in frequency as speckle interferograms of the object (specklegrams) are acquired at each frequency in a Michelson interferometer. The resulting 3D hypercube of specklegrams encode spatial information in the x-y plane of each image with laser tuning arrayed along its z-axis. We present laboratory data of before and after results showing enhanced 3D imaging resulting from precise laser frequency control.
Revised: September 23, 2015 |
Published: September 1, 2015
Citation
Cannon B.D., B.E. Bernacki, J.T. Schiffern, and A. Mendoza. 2015.Three Dimensional Speckle Imaging Employing a Frequency-Locked Tunable Diode Laser. In Applied Advanced Optical Metrology Solutions, August 9, 2015, San Diego, California. Proceedings of the SPIE, edited by E Novak and JD Trolinger, 9576, Paper No. 957604. Bellingham, Washington:SPIE.PNNL-SA-111821.doi:10.1117/12.2188470