Abstract: According to various embodiments, a device may include a light-emitting diode (LED) to generate optical radiation at an operational wavelength with a divergent emission profile, such as a Lambertian emission profile, relative to a planar face thereof. A metalens may be positioned to modify the divergent emission profile of the optical radiation from the LED to have a modified transmission profile. The metalens may comprise, for example, a substrate and a two-dimensional array of passive pillars that extend from the substrate with a radially symmetric pattern of varying pillar diameters. The pillars may be spaced from one another according to a uniform subwavelength interelement spacing. The diameters of the pillars are selected as a function of the operational wavelength to provide a target phase gradient that modifies the divergent emission profile of the optical radiation from the LED to have the modified transmission profile.

Abstract: Systems and methods are described herein that use passive metasurfaces for optical domain image processing, reducing power consumption, latency, and/or computational load in computer vision. As an example, an optical detection device may include an optical assembly that generates multiple copies of an image, which are processed by an array of metasurface filters. Each metasurface filter applies a predefined pattern to a specific image copy. The filtered image copies are used to identify features of interest with reduced computational demands. For example, a first filter may target a first feature, while a second filter targets a second feature. The intensity of the optical radiation output by each filter is used to determine a confidence level that each respective feature is present in the image.

Abstract: Various embodiments and configurations of optical imaging systems are described herein that utilize a metalens for narrowband deflection of target frequencies. For example, one embodiment of a multifrequency metalens includes an in-plane spatially multiplexed array of frequency-specific nanopillars or frequency-specific rows/columns of nanopillars that are intermingled with one another. In other embodiments, transmissive metalenses and/or reflective metalenses are tuned to focus color-separated visible light into red, green, and blue (RGB) channels of a digital image sensor.

Abstract: Systems and methods are described herein for manufacturing high-index, low-absorption materials for use in visible light optical metasurfaces. Methods of manufacturing or forming hydrogenated amorphous silicon (a-Si:H), silicon-rich nitride (SRN), and hydrogenated silicon-rich nitride (SRN:H) are described herein that exhibit high indices of refraction and low extinction coefficients for visible wavelengths of optical radiation. Optical metasurfaces, including optical metalenses and waveguide couplers, are described herein that utilize the a-Si:H, SRN, and/or SRN:H materials.

Abstract: According to various embodiments, a device may include a light-emitting diode (LED) to generate optical radiation at an operational wavelength with a divergent emission profile, such as a Lambertian emission profile, relative to a planar face thereof. A metalens may be positioned to modify the divergent emission profile of the optical radiation from the LED to have a modified transmission profile. The metalens may comprise, for example, a substrate and a two-dimensional array of passive pillars that extend from the substrate with a radially symmetric pattern of varying pillar diameters. The pillars may be spaced from one another according to a uniform subwavelength interelement spacing. The diameters of the pillars are selected as a function of the operational wavelength to provide a target phase gradient that modifies the divergent emission profile of the optical radiation from the LED to have the modified transmission profile.