An electromagnetic scanning mirror integrated with blazed grating and angle sensor for a near infrared micro spectrometer

摘要

This work presents an electromagnetic scanning mirror integrated with blazed grating and an angle sensor for a near infrared micro spectrometer. This device is fabricated on an aluminum coated 7.9 degrees off-oriented (1 1 1) silicon substrate by utilizing the micro-electro-mechanical systems (MEMS) technology. The proposed MEMS electromagnetic scanning grating mirror not only provides high diffraction efficiency by integrating blazed grating, but also realizes the closed-loop control of the scanning angle by designing an angle sensor during the mirror scanning. Finally, in order to verify the effectiveness of this proposed device, the near infrared micro spectrometer is presented. The use of this MEMS electromagnetic scanning grating mirror allows the near infrared micro spectrometer to span a spectral range of 800 nm-1800 nm accurately. Based on this configuration, the near infrared micro spectrometer is extremely simple and only one single InGaAs photodetector is achieved, instead of a detector array.