Electrostatic combdrive-actuated micromirrors for laser-beam scanning and positioning

We describe the design and fabrication of surface-micromachined resonant microscanners that have large scan angles and fast scan speeds. These scanning micromirrors, which are hundreds of micrometers on a side, are driven by electrostatic-comb actuators and have resonant frequencies in the kilohertz range. Fabricated with two or three structural layers of polysilicon, the scanners are compact, extremely light in weight, and potentially very low in cost. Their power consumption is also minimal because the capacitive motors draw very low currents. High-precision positioning (0.01/spl deg/ dynamically and 0.038/spl deg/ statically) over a large angular range (up to 28/spl deg/ optical angle) makes the micromirrors suitable for a variety of optical applications such as laser scanners and printers, displays, holographic data storage, and fiber-optic switches. We have demonstrated microscanners of this type in bar-code readers, which are important devices with a growing number of applications in many industries.

[1]  R. Muller,et al.  Optoelectronic packaging using silicon surface-micromachined alignment mirrors , 1995, IEEE Photonics Technology Letters.

[2]  Kristofer S. J. Pister,et al.  Micro-machined three-dimensional micro-optics for integrated free-space optical system , 1994, IEEE Photonics Technology Letters.

[3]  J. A. Walker,et al.  Fabrication of a mechanical antireflection switch for fiber-to-the-home systems , 1996 .

[4]  Meng Hsiung,et al.  Design and Fabrication of High-Performance Silicon Micromachined Resonant Microscanners for Optical Scanning Applications , 1996 .

[5]  Kam Y. Lau,et al.  Surface-micromachined electrostatic-comb driven scanning micromirrors for barcode scanners , 1996, Proceedings of Ninth International Workshop on Micro Electromechanical Systems.

[6]  F. Merat,et al.  Diffraction grating scanners using polysilicon micromotors , 1995 .

[7]  F. Merat,et al.  THE DEVELOPMENT OF POLYSILICON MICROMOTORS FOR OPTICAL SCANNING APPLICATIONS , 1999 .

[8]  Kurt E. Petersen,et al.  Silicon Torsional Scanning Mirror , 1980, IBM J. Res. Dev..

[9]  N. F. de Rooij,et al.  Line-Addressable Torsional Micromirrors for Light Modulator Arrays , 1994 .

[10]  S. Wakabayashi,et al.  Two Dimensional Silicon Micromachined Optical Scanner Integrated With Photo Detector And Piezoresistor , 1995, Proceedings of the International Solid-State Sensors and Actuators Conference - TRANSDUCERS '95.

[11]  Meng-Hsiung Kiang,et al.  Silicon-micromachined micromirrors with integrated high-precision actuators for external-cavity semiconductor lasers , 1996, IEEE Photonics Technology Letters.

[12]  Jürgen Brugger,et al.  Mechanical and optical properties of surface micromachined torsional mirrors in silicon, polysilicon and aluminum , 1994 .

[13]  K.Y. Lau,et al.  Micromachined polysilicon microscanners for barcode readers , 1996, IEEE Photonics Technology Letters.

[14]  Larry J. Hornbeck,et al.  Deformable-Mirror Spatial Light Modulators , 1990, Optics & Photonics.

[15]  R. Muller,et al.  Laser-to-fiber coupling module using a micromachined alignment mirror , 1995, IEEE Photonics Technology Letters.

[16]  O. Solgaard,et al.  Deformable grating optical modulator. , 1992, Optics letters.

[17]  K.E. Petersen,et al.  Silicon as a mechanical material , 1982, Proceedings of the IEEE.

[18]  M.C. Wu,et al.  Out-of-plane refractive microlens fabricated by surface micromachining , 1996, IEEE Photonics Technology Letters.