Static And Dynamic Characterization Measurement Of MEMS-DMs Based On Stroboscopic Imaging

The technology based on MEMS is more and more popular,but the testing means of MEMS apparatus developed slowly. Dynamic testing technique is very important part of MEMS testing technology,and dynamic testing must be resolved to record the motion moment of MEMS and analyze the out-of plane motion of MEMS surface. After learn a lot of acknowledges and look up so many datum, we set up a MEMS out-of plane motion measuring system based on stroboscopic imaging technique and phase-stepping microscopic interferometry and promoted a new algorithm named double-direction phase unwrapping. In experiments, we make success to measure the out-of plane motion of deformable mirrors. The major works in the paper are as follows(1) We analyse the characters of MEMS-DMs,so we have sufficiency reasons to decide which project should be applied. The paper presents a novel deformable mirrors with transparent electrode based on MEMS technology, the method of designing and fabricating is provided also.(2) The paper has a general explain for the principle of phase-stepping microscopic interferometry, analyzes its technique details including the optical layout of interference microscope, phase-shifting interferometry, and phase unwrapping technique, and discusses various methods or algorithms in each part. A new unwrapping algorithm based on reliability is promoted in the paper, and validate such a algorithm is useful .(3) Setting up a MEMS out-of plane motion measuring system. I selected LED light source by comparing capability, improved LED driving circuit, modified high voltage amplifier circuit, modified Arbitrary Waveform Generator and made each part work together. Advancing a new double-direction phase unwrapping algorithm which unwraps phases along both spatial and temporal directions based on stroboscopic imaging technique., and we acquire time-resolved 3D surface map.(4) Setting up the synchronized control system of stroboscopic imaging based on virtual instrumentation technique. This section includes hardware building, waveform edition of driving signal and control signals, and the design of synchronized control strategy. For time relay in work has a strong influence on system function, calibrating time relay and its countermeasure are carried out and depicted in paper., corresponding solved ways is provided also.(5) Testing the new system is carried out. Measuring the out-of plane motion of deformable-mirrors was performed. Stroboscopic imaging synchronized control system recorded successfully interferograms of deformable-mirrors motion moment. And the data processing software restored its out-of plane motion tracks perfectly. The system also carried out frequency-scanning measurement to the deformable-mirrors, and acquire resonance frequency parameter.