Optical phased array (OPA) devices that uses diffraction to steer an optical beam have found applications ranging from light detection and ranging (LiDAR), free-space optical (FSO) communications, optical switches, holographic display, biomedical imaging, etc. We aim to integrate the OPA system into the application of automobile navigation, which is currently primarily dominated by opto-mechanical scanning based systems, which are usually bulky and relatively slow thus cannot provide the steering speeds and versatility necessary for many applications. Traditional OPAs are usually made of liquid crystal phase shifters, but they have too slow response time for LiDAR applications. MEMS actuated OPAs can have much faster response time. We demonstrate an active 2-D MEMS OPA, in which 25,600 sub-wavelength grating phase shifters are integrated into an aperture of 3.1 mm x 3.2 mm. The diffractive elements are optimized over the NIR telecom optical wavelength bands from 1200 nm to 1700 nm. The MEMS OPA can operate within that band with an 85% optical efficiency.
Project end date: 08/05/19