New 'Fourier Pixels' Can Both Steer and Analyze Light
Researchers have developed a novel type of pixel capable of both controlling and analyzing light, potentially merging camera and display functions into a single device.
Historically, pixels have served distinct roles: either controlling light emission for displays or analyzing incoming light for cameras. Now, a team led by Professor David Norris at ETH Zurich has created a bidirectional pixel that can perform both functions. These innovative pixels are capable of steering light and analyzing its intensity, oscillation phase, and polarization.
The breakthrough relies on the physical phenomenon of light wave interference. When light scatters off a sculpted surface, the resulting waves interact. The precise nanometer-level shaping of the pixel's surface determines how these waves interfere, either reinforcing or canceling each other out. The researchers use this to convert incoming light into surface waves, which then propagate and are scattered back as light patterns.
By employing mathematical Fourier analysis, the team can predict the resulting light patterns and design the required surface topography for specific images. Beyond simple intensity, these "Fourier pixels" can manipulate polarization, the direction of a light wave's electric field oscillation, and create specific light beam shapes, such as those with a central hole. This functionality extends to different wavelengths, enabling the generation of colored images.
Crucially, the same principle can be inverted for analysis. By interfering incoming light with a reference wave on the pixel, researchers can capture and analyze the light's phase and polarization state from the resulting interference pattern. This ability to control and analyze amplitude, phase, and polarization on a single pixel using Fourier analysis is a significant advancement, offering a simpler approach compared to complex models.
This development of bidirectional pixels is significant as it challenges the fundamental separation of display and sensor functions. By integrating light manipulation and analysis at the pixel level, it opens avenues for more compact and efficient optical devices. Such technology could be crucial for advanced imaging systems, potentially impacting fields requiring high-resolution, adaptable optical components, and integrated sensing and display capabilities.
Edited by the news editor with AI from the original report — please refer to the original source.