A team of physicists has made a groundbreaking advancement by creating the smallest pixel ever, measuring just 300 by 300 nanometers. This innovation, detailed in a recent paper published in Science Advances, enables a full high-definition resolution of 1920 by 1080 pixels to fit within an area the size of a breadcrumb.
The ongoing trend of miniaturization in technology is evident in various devices, from smartwatches to augmented reality glasses. This latest research pushes the boundaries further, utilizing optical antennas that convert radiation into finely focused energy bits, achieving brightness levels comparable to that of traditional OLED pixels.
In the realm of display technology, a pixel serves as the smallest unit of information for digital images. Theoretically, reducing pixel size allows devices to accommodate more pixels, enhancing image resolution. However, the paper notes that existing technologies encounter significant manufacturing challenges and efficiency losses at the (sub)micrometer scale.
The challenge becomes particularly pronounced when attempting to shrink OLED pixels beyond the wavelengths of visible light, which range from approximately 400 to 700 nanometers. The geometry of conventional OLED systems, coupled with quantum mechanical effects, leads to imbalances in electrical distribution within the pixel cells.
Jens Pflaum, co-author of the study and a physicist at the University of Würzburg in Germany, explained that simply reducing the size of existing OLED designs could result in current distributions that primarily emanate from the corners of the antenna, creating instability.
The researchers successfully identified a method to mitigate these issues by fabricating a thin insulating layer with a small circular opening at its center, which was placed over a gold optical antenna. This innovative arrangement effectively prevented the formation of disruptive structures known as filaments, which could compromise the pixel”s integrity.
Moreover, the optical antenna plays a crucial role in focusing electromagnetic energy and enhancing brightness. According to Bert Hecht, the study”s senior author, the initial nanopixels demonstrated stability for up to two weeks under ambient conditions, showcasing their potential viability.
Despite the promising results, the system is still in the prototype phase, currently achieving about 1% efficiency. However, the researchers believe that overcoming one of the major obstacles in miniaturizing pixels opens the door to future advancements. They envision a time when displays and projectors could become so compact that they can be seamlessly integrated into wearable devices, ranging from eyeglass frames to contact lenses.
