Optical microelectromechanical system array for free-space retrocommunication

We demonstrate here an optical link for free-space retrocommunication based on an optical microelectromechanical system array with a structure of mechanically active antireflection switch using a thin Si/sub 3/N/sub 4/ membrane. The array consists of 215 identical single devices with a total active area of 36 mm/sup 2/ and was fabricated with the normal surface sacrificial micromachining. An overfilled reflectance contrast of 3 dB was observed at 6328 /spl Aring/ and a data rate of 100 kb/s shown in 50 mtorr vacuum. A design tradeoff between the high optical filling factor and the high working frequency is discussed.