Technicolor was a breakthrough innovation in our history that changed how we see the world around us. Today, we hold unique methods for observing the world around us particularly through polarization.
"Polarization is a feature of light that is changed upon reflection off a surface," said Dr. Paul Chevalier, a postdoctoral fellow at SEAS and co-author of the study. "Based on that change, polarization can help us in the 3D reconstruction of an object, to estimate its depth, texture and shape, and to distinguish man-made objects from natural ones, even if they're the same shape and color."
However, current-generation polarization-sensitive cameras are expensive, bulky, and have limited potentiality. "If we want to measure the light's full polarization state, we need to take several pictures along different polarization directions," said Noah Rubin, first author of the paper and graduate student.
Now, a study published in Science, describes the development of a small and portable camera that can polarize in a single shot. "This research is game-changing for imaging," said Dr. Federico Capasso, senior author of the paper. "Most cameras can typically only detect the intensity and color of light but can't see polarization. This camera is a new eye on reality, allowing us to reveal how light is reflected and transmitted by the world around us."
The miniature sized camera -- roughly the size of a thumb -- could hold advanced applications ranging from the autonomous use of vehicles to the detection of camouflaged objects.
"Previous devices either used moving parts or sent light along multiple paths to acquire the multiple images, resulting in bulky optics. A newer strategy uses specially patterned camera pixels, but this approach does not measure the full polarization state and requires a non-standard imaging sensor. In this work, we were able to take all of the optics needed and integrate them in a single, simple device with a metasurface,” said Rubin. "This technology could be integrated into existing imaging systems, such as the one in your cell phone or car, enabling the widespread adoption of polarization imaging and new applications previously unforeseen.”
Researchers have harnessed the world of polarization by designing a metasurface that directs light.
"This research opens an exciting new direction for camera technology with unprecedented compactness, allowing us to envision applications in atmospheric science, remote sensing, facial recognition, machine vision and more," stated Capasso.
Source: Harvard University
