A method and system for measuring the temporal response of a micromirror
array to a variety of driving signals. A micromirror array is illuminated
with a coherent light source so that a diffraction pattern is reflected
from the micromirror array. One or more photodetectors are aligned with
spots of light in the diffraction pattern that correspond to orders of
the diffraction pattern. Diffraction pattern theory predicts that the
intensity of these spots of light will vary as the tilt angle of the
micromirrors is changed. Thus, by measuring the relative intensity of the
spots of light as the micromirror array is provided with a variety of
driving signals, many performance characteristics of the micromirror
array can be measured. Some of these characteristics include the impulse
response, the forced resonant frequency (i.e. the natural frequency), the
damped resonant frequency, the quality factor of the micromirror
response, the damping factor of the micromirror response, and the
frequency transfer function. According to another aspect of the
invention, the electromechanical compliance of the micromirrors in the
micromirror array can also be measured. It is further contemplated that
all of these measurements can be localized to specific regions on the
surface of the micromirror array so that the variance of different
characteristics across its surface can be analyzed. Another aspect of the
disclosed invention is the measurement of the tilt angle of the
micromirror array at a non-biased state.