A Fully Solid-State Beam Scanner for FMCW LiDAR Application

We demonstrate a fully solid-state beam scanner that incorporates a Si3N4 photonic integrated switch array, a collimator lens, and a lithographically patterned diffraction grating. The off-chip components enable nearly circular output beams under the reduced system complexity. By manipulating the optical switch array and tuning the input wavelength, two-dimensional beam steering with <inline-formula> <tex-math notation="LaTeX">$32\times23$ </tex-math></inline-formula> = 736 resolvable spots across a <inline-formula> <tex-math notation="LaTeX">$14.3^{\circ }\times 9.9^{\circ }$ </tex-math></inline-formula> field of view (FOV) is realized. Furthermore, the coherent ranging within 18 m is demonstrated experimentally by utilizing the triangular frequency modulation. The tested results validate the feasibility of the proposed beam scanner, which might offer a flexible, scalable, and easily-implemented solution for the solid-state frequency modulated continuous-wave (FMCW) LiDAR.