University of California, Davis
Micro Instruments and Systems Laboratory
apwallace@ucdavis.edu, smith@ece.ucdavis.edu, collins@ece.ucdavis.edu
Microfabricated Linear Electromagnetic Motor:
As part of the development of a micro Fourier Transform Spectrometer, a micro linear translational actuator has been demonstrated.  Fabricated with KOH etching of silicon, wafer bonding, gold electroplating, and patternable polyimide, the actuator can provide long range mirror tranlation at a constant velocity.  The permanent magnet mounted on the dovetail slider is controlled by electrical coils patterend on the backside of the dovetail structures.  Feedback is obtained using a laser reflecting off the mounted mirror to a position sensitive diode.  This work has been published at Transducers 99.  Links to both the conference paper and presentation are included below.
Published at Transducers 99, Sendai, Japan
Presentation
Paper
Note:  the background is a microfabricated gold coil

 
 
 


Diagram of a typical Fourier transform spectrometer 
with Michelson interferometer design.  As the mirror 
moves a monochromatic light source will experience 
a cyclic intensity distribution at the detector due to 
interference.

 
 
 
 
 


Typical interferogram for a broadband optical source.  At the zero path difference (ZPD) all wavelengths are in phase and a centerburst occurs. 
As the mirror moves past the ZPD, the different wavelengths destructive

 
 
 


Actual interferograms and Fourier Transformed spectra for a 650nm interference filter.  (A). shows the interferogram and Fourier Transformed spectrum obtained for the micromachined FTS.  For comparison, (B). shows the interferogram and spectrum for the same filter obtained from a commercial FTS (Brucker).