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A 3mm narrow interval deformable mirror (DM) with tip-tilt stage has been developed for astronomical instruments. Benefiting from its compact design, the adaptive optics system can be built with simple structure and smaller optical elements. First, a 37-elements prototype mirror has been developed for our 1.8-meter telescope, which interval space is 3mm, maximum tilt is ±10’, and maximum deformation is ±2μm. Based on this mirror, a simple adaptive optics system has been set up and its performance was tested in the laboratory especially the closed-loop correction ability. This adaptive optics subsystem is scheduled to be mounted at one folded Cassegrain focus of the 1.8-meter telescope this year, and comparison test for star compensation observation using this compact system and conventional adaptive optics system will also be carried out at the same time.

For better understanding and forecasting of the solar activity and the corresponding impacts human technologies and life on earth, the high resolution observations for Sun are needed. The Chinese Large Solar Telescope (CLST) with 1.8 m aperture is being built. The CLST is a classic Gregorian configuration telescope with open structure, alt-azimuth mount, retractable dome, and a large mechanical de-rotator. The optical system with all reflective design has the field of view of larger than 3 arc-minute. The 1.8 m primary mirror is a honeycomb sandwiches fused silica lightweight mirror with ULE material and active cooling. The adaptive optics system will be developed to provide the capability for diffraction limited observations at visible wavelengths. The CLST design and development phase began in 2011 and 2012 respectively. We plan for the CLST’s starting of commission in 2017. A multi-wavelength tomographic imaging system with seven wavelengths range from visible to near-infrared wavelength is considered as the first light scientific instruments. In this paper the main system configuration and the corresponding post focal instruments are described. Furthermore, the latest progress and current status of the CLST are also reported.

A low-order solar adaptive optics (AO) system, which consists of a fine tracking loop with a tip/tilt mirror and a correlation tracker, and a high-order correction loop with a 37-element deformable mirror, a correlating Shack-Hartmann wavefront sensor and a high-order wavefront correction controller, had been successfully developed and installed at 1-m New Vacuum Solar Telescope of Full-shine Lake (also called Fuxian Lake) Solar Observatory. This system is an update of the 37-element solar AO system designed for the 26-cm Solar Fine Structure Telescope at Yunnan Astronomical Observatory in 2009. The arrangement of subapertures of the Shack-Hartmann wavefront sensor was changed from square to hexagon to achieve better compensation performance. Moreover, the imaging channel of the updated system was designed to observe the Sun at 710nm and 1555nm simultaneously. The AO system was integrated into the solar telescope in 2011, and AO-corrected high resolution sunspots and granulation images were obtained. The observational results show that the contrast and resolution of the solar images are improved evidently after the correction by the AO system.

The 127-element adaptive optical system for the 1.8m astronomical telescope is being developed. In this system, the wavefront correction loop consists of a 127-element deformable mirror, a Hartmann-Shack (H-S) wavefront sensor, and a high-speed digital wavefront processor. The tracking system consists of a tip-tilt mirror, a tracking sensor and a tracking processor. The wavelength for the H-S wavefront sensor ranges from 400-700nm. The imaging observation wavelengths range from 700-1000nm and 1000-1700nm respectively. In this paper, the optical configuration of 1.8m telescope will be briefly introduced. The 127-element adaptive optical system is described in detailed. Furthermore, the preliminary performances and test results on the 127-element adaptive optical system is reported.

The 61-element upgraded adaptive optical system for the 1.2m telescope of Yannan Observatory for astronomical observation had been in operation since May 2004. In this paper, the 61-element upgraded adaptive optical system for 1.2m telescope of Yunnan Observatory will be briefly described. The performance on the 61-element upgraded adaptive optical system is analyzed. Furthermore, the observational results for the stars will be presented.

A tilt-correction adaptive optical system installed at 430mm Solar Telescope at Nanjing University has been in operation. It is made up of a tip-tile mirror, a correlation tracker and an imaging CCD camera. The Absolute Difference algorithm is used in order to detect image motion in the correlation tracker. The sampling frequency of the system is 419Hz. In this paper, the configuration of the system is described. The observation results are reported. Furthermore, the performance of the system is analyzed. The residual jitter of 0.14arcsec has been achieved. The error rejection bandwidth of the system can be adjusted in the range from 5Hz to 28Hz according to the beacon size and the strength of the atmospheric turbulence.

A 21-element adaptive optics system installed at the 2.16m telescope of Beijing Astronomical Observatory has been in operation. It is made up of a pair of shearing interferometer (SI), a 21-element deformable mirror, a fast steering mirror, a digital wavefront processor, a precise tracking subsystem and a PtSi IR CCD camera. In this paper the performance of the system will be briefly introduced. Its observation results in IR K band and in visible band are reported. For the system, 0.25 arcsec resolution has been achieved in IR K band, which approaches the diffraction limit of the 2.16m aperture. In visible band, 0.13arcsec resolution has been also achieved. For the star of magnitude 9.m2, the compensation of the system is still effective. The error rejection bandwidth of the system can be adjusted in the range from 5Hz to 40Hz according to the beacon magnitude and the strength of the atmospheric turbulence.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.