Focus-Free Camera Uses A Newly Designed Flat Lens
Researchers have been able to create a new camera that doesn't require focusing using a single lens that is very thin. The technology has significant benefits over traditional cameras, like those used in smartphones today. One of the significant benefits is that current cameras require multiple lenses to form high-quality, in-focus images.Researchers on the project from the University of Utah say that the flat lens can drastically reduce the weight, complexity, and cost of cameras and other imaging systems. At the same time, the new flat lenses also increase the functionality of the cameras. The team says that their optics could enable thinner smartphone cameras, improved and smaller cameras for biomedical imaging, and more compact cameras for use in automobiles.
The flat lens can maintain focus on objects that are about six meters apart from each other. The lens itself uses a nanostructure pattern on a flat surface rather than bulky glass or plastic to achieve the optical properties needed to control the way light travels as a traditional camera lens does. Scientists believe that the new flat lens could have many applications outside of photography, including very efficient illumination for LIDAR that is critical for autonomous automobiles.
Researchers say that to enable a traditional lens to focus light, it transforms parallel light waves into spherical waves that converge into a focal spot. The important breakthrough with the flat lens was the realization that waves with other shapes can produce a similar effect. The scientists then chose the best lens design for depth focus and used nanofabrication techniques to build their prototype lens.
Demonstrations of the new lens used infrared light and a relatively low numerical aperture. In the future, the team plans to extend the lens to larger apertures and to use it with the visible light spectrum. The group says they also need to ensure that the lenses could be mass-manufactured before it can be commercialized.