@article {779, title = {A Preliminary Model for a Distance Sensor, using a Radiometric Point of View}, journal = {Sensor Letters}, volume = {7}, year = {2009}, month = {02/2009}, pages = {17-23}, publisher = {American Scientific Publishers}, abstract = {In this paper, a preliminary model for a radiometric image formation process for a CMOS camera, based on the radiometric response function of a camera, is presented. The model is used to estimate the distance between an infrared emitter diode and a camera using gray-level intensity of images, and the inverse-square distance law. To define the model, the behaviors of measured sensor irradiance with emitter power, camera exposure time, and distance between emitter and camera are shown and also integrated. Furthermore, an application for distance estimation is also presented. Results show that a maximum error of 4 cm was obtained over a range of measurement from 34 to 100 cm. }, issn = {1546-198X}, doi = {10.1166/sl.2009.1004}, author = {Angel Cano and Jose L. Lazaro and P. Fernandez and Oscar Esteban and Carlos Andres Luna} }