Planar Luneburg Lens

Optical beam steering is a critical technology in numerous sectors ranging from telecommunications to defense and biomedical systems. In systems requiring light-direction control, the need for a reliable, high-performing optical beam- steering device becomes crucial. Traditional aplanatic lenses have been used, yet they show deficiencies like nonuniform beam quality in different directions. Current beam-steering devices suffer from a limited field of view, aberrations off boresight, and sensitivities to misalignment or fabrication imperfections. These limitations often affect the uniformity of a beam, decreasing the overall performance and effectiveness of the device. Also, many existing devices require complex and costly manufacturing processes, limiting their feasibility and versatility.

Technology Description

The integrated optical beam steering device features a unique composition of a planar Luneburg lens and a curved grating coupler. The lens, likely composed of subwavelength features, collimates beams from different inputs in various directions within the lens plane. The grating coupler then diffracts these collimated beams out of the lens plane. Beam direction can be controlled within and outside the plane through lens illumination and beam wavelength variation. What sets this technology apart is its capability of operating over an extremely wide field of view — up to 180° — without any aberrations off boresight. This approach offers uniform beam quality in all directions, a feature not seen in aplanatic lenses. The circular symmetry of the planar Luneburg lens allows for this design. Additionally, this lens is robust to misalignment and fabrication imperfections and can be fabricated using standard CMOS processes.