Characterization of a digital micromirror device for use as an optical mask in imaging and spectroscopy

The digital micromirror device (DMD) is a micro-optical-electro-mechanical structure (MOEMS) consisting of an array of 16 mu m x 16 mu m square mirrors positioned on a 17 mu m pitch. Each individual mirror can be tilted +/- 10 degrees relative to the DMD substrate; the tilt is along the diagonal direction of the micromirror. The device was invented and manufactured by Texas Instruments (TI), Inc. TI packages the DMD as an OEM product for use in projection displays. We are investigating the use of the DMD as a spatial light modulator for precision imaging and spectroscopy applications. This includes optical characterization of the device, as well as systems engineering to operate the device. Some of the performance metrics to be considered are the diffraction efficiency, optical-switching contrast, background scattering properties, mirror crosstalk, and the modulation transfer function (MTF).