‘Digital lenses’ the next big thing?

‘Lenses remain essentially unchanged since medieval times,’ according to the technology pioneers aiming to fundamentally alter the analogue nature of conventional lens-making. They have a ways to go yet, though.

ST Microelectronics is a semiconductor manufacturer which has teamed up with ‘meta-optics’ start-up Metalenz in a collaboration that will see ST manufacture lenses based on Metalenz’s meta-optics technology.

Metalenz, founded in 2016, has developed technology whereby complex optical performance can be built on a single semiconductor layer, enabling large-scale production of optics in semiconductor foundries – effectively ‘printing’ lenses like computer chips.

Metalenz has its origins at Harvard University, where the meta-surface optics technology was invented. The collaborators are anticipating going into mass production by the end of this year.

The first target is cameraphones, which like digital cameras, use lens elements stacked over an image sensor. Metalenz’s design uses a single lens built on a glass wafer between just one and three square millimetres in size.

Instead of using curved surfaces, ‘meta-surface optics’ combines multiple optical functions in a single flat layer. This shrinks the size of each lens element while also cutting the number of lens elements needed, reducing the size of the optical lens, the number of components, the complexity of assembly, and the overall cost. Under a microscope ‘nanostructures’ measuring one-thousandth the width of a human hair can be seen on the Metalenz surface. They bend light rays to enable a single lens camera system to perform like a more sophisticated lens array. The silicon nanostructures manipulate light rays in a way that allow for brighter and sharper images compared to standard lens elements.

Smartphone camera development is constrained by the need to pack small but nonetheless complex lenses into an increasingly thin form factor. Hence the unwanted ‘camera bumps’ in some of the more optically sophisticated phones.

‘A camera built around this new flat-lens technology can collect more light for brighter images and produce images of the same or better quality than traditional refractive lenses while consuming less power and taking up less space,’ the press release explained.

ST will integrate the Metalenz’s meta-surface optics technology into ST’s existing diffractive optics manufacturing process at its 300mm wafer manufacturing plant in Crolles, France.

First cab off the rank is reported to be a 3D camera for an unnamed smartphone brand.

‘Given the benefits, optical lenses made in a semiconductor wafer fab could someday be as common as traditional refractive lenses,’ the Metalenz announcement concluded.