Two categories of optical beam steering micro-electro- mechanical systems (MEMS) were investigated: variable blaze gratings (VBGs) and linear optical phased arrays. All devices were surface micromachined using the multi-user MEMS processes (MUMPs). VBGs use an adjustable blaze angle to direct the majority of reflected light into a selectable diffraction order. Diffraction efficiencies greater than 50% were demonstrated. Linear optical phased arrays use a single row of piston micromirrors to create a far-field pattern with a steerable main lobe along one axis. All devices were constructed of polysilicon and gold and were actuated with electrostatic force. Electrostatic actuation provides high speed operation at a very low drive power. These optical beam steering devices discussed in this work are less optically efficient than a single pivoting mirror, but they require no post-fabrication assembly and can handle large beam diameters. Also, the low individual mass of the elements in surface micromachined VBGs and optical phased arrays yield faster system response times than a single macroscale pivoting mirror.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.