University of Michigan researchers have developed a new type of OLED that could potentially replace bulky night vision goggles with lightweight glasses, offering a more practical and cost-effective solution for prolonged use. This new OLED device is capable of amplifying near-infrared light into visible light more than 100 times, without the need for the heavy vacuum layers and high voltage typically required by traditional image intensifiers found in current night vision systems. By optimizing the design of the device, much higher levels of amplification may be achieved. The device operates at a lower voltage than traditional image intensifiers, which could lead to significantly reduced power consumption and longer battery life.
The newly developed OLED device integrates a photon-absorbing layer that converts infrared light into electrons, and a five-layer stack of OLEDs, where these electrons are converted into visible light photons. Through a positive feedback cycle, the chain reaction greatly amplifies the output light produced for a given input light. Unlike previous OLEDs, this device exhibits high photon gain, where one input photon yields multiple output photons, resulting in efficient light conversion. Additionally, the device displays a memory behavior known as hysteresis, which allows it to remember and process past input illumination levels. This feature could potentially be applied in computer vision systems that interpret incoming light signals and images.
The memory behavior of the OLED device creates some challenges for night vision applications, but it also presents an opportunity for image processing that simulates the human visual system. The ability to remember past inputs could enable these OLEDs to mimic neuron-like connections, which would allow input images to be interpreted and classified without requiring a separate computing unit. The researchers used widely available materials and methods in the fabrication of the device, increasing cost effectiveness and scalability for further applications of this technology. The research was conducted in partnership with OLEDWorks and RTX, and is patent-pending by OLEDWorks and Penn State University.
The thin film stack of the OLED device is less than a micron thick, much thinner than a strand of hair. This thin design contributes to the lightweight nature of the device, making it suitable for integration into glasses for night vision applications. The thin film design also contributes to reducing power consumption and extending battery life due to the lower voltage operation of the device compared to traditional image intensifiers. The ability of the device to amplify light efficiently and effectively without the bulk and weight of existing night vision systems makes it an attractive alternative for practical and prolonged use in various applications.
The technology developed by the University of Michigan researchers has the potential to revolutionize the field of night vision by offering a lightweight, cost-effective, and highly efficient solution for generating visible light from near-infrared inputs. The memory behavior exhibited by the OLED device could lead to advancements in computer vision systems, with potential applications in image processing that mimic the human visual system. By utilizing off-the-shelf materials and methods already used in OLED manufacturing, the researchers have created a device that is not only innovative but also scalable and cost-effective for future implementations. With support from DARPA, this groundbreaking research paves the way for the development of next-generation night vision technology that is more practical, efficient, and user-friendly.
