A new imaging system can gather significantly more color information than the human eye and conventional cameras, potentially enabling assisted-vehicle-driving systems, better identification of counterfeit bills and more accurate medical imaging. A team at the University of Granada designed the system, which is based on transverse field detectors (TFDs) developed at the Polytechnic University of Milan, as well as a matrix of multispectral filters. The system is capable of obtaining up to 36 color channels, allowing researchers to capture multispectral images in real time. The TFD system can extract full color information from each pixel in an image without the need for RGB color filters. Conventional color-imaging sensors and detectors can only extract information from one of the three RGB filters in each pixel, while algorithms are applied to the remaining two colors. “To study the way in which light interacts with our environment can give us very valuable information on its behavior in a totally innocuous and noninvasive way,” said doctoral student Miguel Angel Martinez Domingo, a researcher with the University of Granada. With the TFD system, each photon penetrates at a different depth, depending on its wavelength and color. Collecting these photons at varying depths on the sensor’s silicon-based surface prompts different channels of color to be separated. Using the TFDs, the researchers applied a transversal electric field of controlled but varying intensity, allowing the researchers to “modulate the depth at which the photons in each color channel are collected.” “This offers the possibility of fine tuning the way in which these sensors turn the light they receive into electric signals,” Domingo said. Multispectral images created using the TDF system have potential for better remote sensing, satellite images, military and defense technology, as well as industrial applications, robotic vision, assisted or automatic driving. For more information, visit www.ugr.es.
Vision Sensor