@article {783, title = {Sensor for distance estimation using FFT of images}, journal = {Sensors}, volume = {9}, year = {2009}, month = {12/2009}, pages = {10434-10446}, abstract = {In this paper, the problem of how to estimate the distance between an infrared emitter diode (IRED) and a camera from pixel grey-level intensities is examined from a practical standpoint. Magnitudes that affect grey level intensity were defined and related to the zero frequency component from the FFT image. A general model was also described and tested for distance estimation over the range from 420 to 800 cm using a differential methodology. Method accuracy is over 3\%.}, issn = {1424-8220}, doi = {10.3390/s91210434}, url = {http://www.mdpi.com/1424-8220/9/12/10434/}, author = {Jose L. Lazaro and Angel Cano and P.R. Fern{\'a}ndez and Carlos Andres Luna} }