The analysis of scattering characteristics of diffractive optics based on Finite-difference time-domain method is
presented. And its scattering pattern along the surface is gotten. It shows that the scattering intensity in the discontinuous
surface is much higher than the continuous surface. This causes the decrease of diffractive efficiency. Binary optics with
multilevel relief can cause more scattering than micro optics with continuous relief, so it is not suitable for being used in
the situation where phase varies rapidly.
This paper discussed the SI-GaAs photoconductive switch entering into the nonlinear mode under the high biased
field and the result of photovoltaic delay, as well as, analyzed the phenomena of electric pulses delay under the
high biased field. Meanwhile, pose a theory that the captive effects of impurities in deep energy level of
semi-conductor materials is the main reason of photovoltaic delay, moreover, calculation to account the
relationship between the transmission of charge domain and photovoltaic delay, and received a result that
inosculate with the experiment.