Two new micro programmable gratings and their potential applications

This paper presents the basic concepts of design and fabrication for two new micro programmable gratings, and gives preliminary research results for demonstrating their potential applications. Firstly, a surface-micromachined micro programable grating with its blazed angle electrostatically modulated was described. To maximize the blazed angle, dimples were taken as key components for the grating beams and their depth was specially designed to close to the air gap. After fabrication, the realized maximum blazed angle can reach 5.1deg. Then, the micro programmable blazed grating was applied for multispectral imaging and the initial results were obtained. Secondly, a micro programmable pitch-tunable grating based on the silicon-on-glass technology was introduced and fabricated. By changing the driving voltage from 0 V to 45 V, the grating pitch is increased from 10 mum to 20 mum respectively and accordingly, the measured first-order diffraction angle is changed from 3.86deg to 1.94deg for an incident laser of 650 nm. This property enables the pitch-tunable grating suitable for optical switch applications.