A new OLED gadget created by researchers at the University of Michigan can convert near-infrared light into visible light, providing over 100 times the amplification of conventional image intensifiers without their size or complexity. Compared to the average human hair, which is roughly 50 microns thick, this invention uses a thin film that is less than a micron thick. This gadget works at a far lower voltage than conventional systems, which require high voltage and bulky vacuum layers. This reduces power consumption and lengthens battery life.
In order for the device to function, an infrared photon-absorbing layer must be combined with a five-layer OLED stack to convert infrared light into electrons, which are subsequently converted into visible light photons. Five photons should ideally be created for each electron that travels through the OLED layers. A positive feedback loop is created when some of these photons are released and others are reabsorbed, greatly increasing the amount of light that is produced from the original light input.
Earlier OLED technologies were limited to one-to-one photon exchange for the conversion of infrared light into visible light. But this new gadget which was created with help from lead author Raju Lampande and U-M professor Chris Giebink is the first to show substantial photon gain, which amplifies light within a thin film device.
Another interesting characteristic of this technology is its memory behavior, known as hysteresis. Once illuminated, the device may “remember” the past intensity and duration of the light, staying “on” long after the initial lighting is shut off. While this raises hurdles for night vision applications, it introduces new opportunities for image processing that mimics human neural networks, making it an attractive promise for future applications in computer vision. With its readily accessible OLED materials and manufacturing processes, this technology is scalable and reasonably priced, indicating a high likelihood of wider adoption over the road.