Stacked-actuator Deformable Mirror Research Articles

Atmospheric Turbulence with Kolmogorov Spectra: Software Simulation, Real-Time Reconstruction and Compensation by Means of Adaptive Optical System with Bimorph and Stacked-Actuator Deformable Mirrors

Atmospheric turbulence causes refractive index fluctuations, which in turn introduce extra distortions to the wavefront of the propagated radiation. It ultimately degrades telescope resolution (in imaging applications) and reduces radiation power density (in focusing applications). One of the possible ways of researching the impact of turbulence is to numerically simulate the spectrum of refractive index fluctuations, to reproduce it using a wavefront corrector and to measure the resultant wavefront using, for example, a Shack–Hartmann sensor. In this paper, we developed turbulence simulator software that generates phase screens with Kolmogorov spectra. We reconstructed the generated set of phase screens using a stacked-actuator deformable mirror and then compensated for the introduced wavefront distortions using a bimorph deformable mirror. The residual amplitude of the wavefront reconstructed by the 19-channel stacked-actuator mirror was 0.26 λ, while the residual amplitude of the wavefront compensated for by the 32-channel bimorph mirror was 0.08 λ.

Water-cooled stacked-actuator flexible mirror for high-power laser beam correction

To correct for phase distortions in high-power laser setups a stacked-actuator deformable mirror with water cooling was developed. The main characteristics of the mirror such as the initial surface profile, response functions of the actuators, maximal stroke and amplitude frequency characteristic were shown. The quality of initial surface was equal to 0.14 µm (P-V). The maximal stroke of the mirror was about 7 µm. The first resonant frequency was found at 18.5 kHz, that would allow to exploit such wavefront corrector in high-speed adaptive optical systems. The measured hysteresis of the deformable mirror was equal to 12%. Experimental investigations of proposed cooling method of the mirror surface through actuators were performed.

High-spatial resolution stacked-actuator deformable mirror for correction of atmospheric wavefront aberrations.

Deformable mirrors are vital components of any adaptive optical system. Considering such a crucial role in compensation of incident wavefront distortions, the main requirements are imposed on these elements that determine performance of the entire system. To correct for phase distortions in high-power laser complexes a stacked-actuator deformable mirror with water cooling was developed. The main characteristics of the mirror, such as the initial surface profile (flatness), response functions of the actuators, maximal stroke, and amplitude-frequency characteristics are presented in this paper. Experimental investigations of the proposed cooling method of the mirror surface through actuators were performed.

Cooled Stacked-Actuator Deformable Mirror for Compensation for Phase Fluctuations in a Turbulent Atmosphere

Abstract—A wavefront corrector has been designed in the form of a cooled stacked-actuator deformable mirror for the correction of aberrations of laser radiation propagating through the turbulent atmosphere. The main parameters of this mirror are theoretically estimated. A technique for cooling the reflecting surface of the wavefront corrector through piezo actuators is suggested and experimentally tested. The main parameters of the deformable mirror are measured: the initial shape of the surface, the response functions of the actuators, the mirror stroke, and the frequency-amplitude characteristic of optical surface.

Cooled stacked-actuator deformable mirror for compensation of phase fluctuations in a turbulent atmosphere

Cooled stacked-actuator deformable mirror for compensation of phase fluctuations in a turbulent atmosphere

Continuous facesheet low voltage deformable mirrors

Litton/Itek Optical Systems has been a leader in the development of deformable mirrors for use in high quality optical systems since 1973. The monolithic piezoelectric mirror (MPM), which was introduced in 1974, has been the quality product against which all other visible wavelength compensators have been compared. The stacked actuator deformable mirror (SADM), first delivered in 1980, set new performance standards for infrared systems. These devices continue to maintain high quality large stroke performance in the field. In 1981 Itek began the development of a new concept in deformable mirrors, the low voltage electrodisplacive mirror (LVEM). Itek teamed with Bell Aerospace in 1984 to develop a cooled silicon electrodisplacive mirror (CSEM) technology. The CSEM development emphasized extending the LVEM technology to high energy laser systems applications by incorporating a silicon multiport pin-fin heat exchanger into the mirror structure. Recently, in 1988, Itek began developing a cost efficient cooled mirror technology compatible with moderate flux levels and quantity production. The LVEM uncooled technology has matured and represents the current state of the art in deformable mirror performance. Upon its maturity, the CSEM technology will provide both high performance and cost efficient cooled deformable mirrors for the needs of the high energy laser community.