Fabrication and Integration of Binary Phased Fresnel Lens and Micro Linear Actuator for IR Laser Beam Scanning Application

Abstract

This study presents a MEMS IR-laser beam scanning system consisted of the micro Fresnel lens and linear comb actuators. The merits of this study is to fabricate and further integrate the binary phase Fresnel lens, micro springs, and micro electrostatic actuators through the silicon micromachining processes to achieve the proposed IR-laser beam scanning system. Thus, the difficulty and problem resulted from assembly can be prevented. The proposed IR-laser beam scanner is a spring-mass system driven by linear comb-drive actuators, and operates at the resonant frequency to enlarge the scanning angle. Measurements indicate the scanner has a resonant frequency of ~2 kHz (exceeds the millisecond minimum response time requirement for application), and a displacement of greater than ±20μm at a driving voltage of VDC=12.5V, Vpp=18V. Moreover, the 1550 nm infrared laser beam has a deflection angle of ±6.84°.