The openloop Liquid crystal adaptive optics for astronomical application

Atmospheric turbulence deteriorates the image quality of astronomical objects and limits the spatial resolution of large aperture optical telescopes. Adaptive optics (AO) corrects the aberrations induced by atmospheric turbulence in real time, which concentrates the incident light and enables the telescope to achieve the diffraction-limited resolution on-axis or over an extended field-of-view (FoV). In this paper, we present the transfer function of our open-loop liquid crystal adaptive optics system. Based on the transfer function, we calculated the bandwidth of our nematic LC AO system: -3dB bandwidths are about 57.0 Hz and 82.4Hz for high order aberration and tilt-tip compensation control, respectively. Through further improvements on LC material, electronic interface port, shortened data processing time and optimized control, we will get a better LC AO system.