Login / Signup

Miniature Deformable MEMS Mirrors for Ultrafast Optical Focusing.

Afshin Kashani IlkhechiMatthew T MartellRoger J Zemp
Published in: Micromachines (2022)
Here, we introduce ultrafast tunable MEMS mirrors consisting of a miniature circular mirrored membrane, which can be electrostatically actuated to change the mirror curvature at unprecedented speeds. The central deflection zone is a close approximation to a parabolic mirror. The device is fabricated with a minimal membrane diameter, but at least double the size of a focused optical spot. The theory and simulations are used to predict maximum relative focal shifts as a function of membrane size and deflection, beam waist, and incident focal position. These devices are demonstrated to enable fast tuning of the focal wavefront of laser beams at ≈MHz tuning rates, two to three orders of magnitude faster than current optical focusing technologies. The fabricated devices have a silicon membrane with a 30-100 μm radius and a 350 nm gap spacing between the top and bottom electrodes. These devices can change the focal position of a tightly focused beam by ≈1 mm at rates up to 4.9 MHz and with response times smaller than 5 μs.
Keyphrases
  • high speed
  • high resolution
  • cardiovascular disease
  • body mass index
  • energy transfer
  • monte carlo
  • physical activity
  • gold nanoparticles
  • carbon nanotubes