PHOTOGRAPH: JUSTIN KNIGHT/METALENZ
Imagine a world like this. An in-vehicle camera detects thin ice on the road surface in advance and alerts the driver. Alternatively, your smartphone's camera can analyze lesions that appear on your skin to determine if you have cancer. And Apple's facial recognition function "Face ID" will recognize your face even if you are wearing a mask. Metalenz's PolarEyes polarization technology, which is developing next-generation lenses, has the potential to make all of this possible. Technology that realizes a completely flat lens is about to bring innovation to smartphone cameras Metalenz announced a camera system equipped with a flat lens for mobile terminals called "Optical Metasurface" in 2021 It was the year. The system is space-saving, but the image quality is comparable to, if not superior to, conventional smartphone cameras. Most of the cameras installed in smartphones have a structure in which many lenses are stacked. For this reason, it is inevitably thick and a "protrusion" is formed. Metalenz technology, on the other hand, uses just one lens. The nanostructures in the lens redirect light passing through it and focus it onto the sensor, producing an image as bright and sharp as a conventional camera. According to Metalenz CEO Rob Devlin, the technology will be in products in the second quarter of 2022. "PolarEyes", which Metalenz announced in January 2022, is the second-generation technology, and it may be installed in electronic devices in 2023. The underlying technology is the same, but the difference is that the nanostructures retain the polarization information of light. Conventional cameras, such as those found in smartphones, capture only luminosity and color without this information. If the amount of data that can be acquired increases, the range of smartphone functions may expand.
The value of polarization information indicating the direction of light
Enlarged image of the nanostructure designed by Metalenz
Light is a type of electromagnetic wave that propagates in the form of waves. When light hits a particular object (such as a crystal), its waveform changes and it begins to vibrate in a unique way. “Polarization information is all about the direction of the light,” says Devlin. “The light that hits the camera after being reflected off a smooth surface, a bumpy surface, some corners, certain molecules, etc., will be directed differently depending on the material, molecule, or object that reflects it. , contrast is born, and you can grasp what the material is.” The waveform of light reflected on ordinary roadside ice is different from that reflected on thin ice. If a camera can capture this information, machine-learning algorithms for computer vision can learn the difference between thin ice and regular ice. The car would then be able to give the driver advance notice of impending danger. You may not be aware of it, but polarization technology is all around us. Polarizing filters are used in the panels of LCD TVs and PC monitors, and the polarizing lenses of sunglasses cut glare and reflected light, and isolate specific wavelengths. However, until now, polarization imaging, which captures the unique vibrations of light waves, has been used mainly only in scientific and medical research. One such researcher is Tom Cronin, a visual ecologist who studies the crustacean mantis shrimp at the University of Maryland, Baltimore County. Mantis shrimp are known to be able to sense polarized light, which allows them to see well in murky water. "They use polarized light to communicate and navigate," Cronin says of the strange creature. Most equipment for polarization imaging is large and expensive. Metalenz's PolarEyes, on the other hand, are small and cost-effective enough to fit in a smartphone as a camera.
