In this paper, an active optics and co-focus experimental system of segmented mirror is built. Firstly, a support structure of segmented mirror is designed and it is verified by simulation to meet the requirement for ...In this paper, an active optics and co-focus experimental system of segmented mirror is built. Firstly, a support structure of segmented mirror is designed and it is verified by simulation to meet the requirement for the experimental system of segmented mirror. In this system, the large de-focus and tilt/tip errors of the segmented mirror are adjusted by observing the density and contrast of interference fringes based on isoclinic interference theory until the defocus and tilt/tip errors are in the detective range of the Shack–Hartmann. Then, the Shack–Hartmann is used to measure them and they are adjusted by actuators. The actuators are controlled by active optics to realize the closed-loop adjustment and maintenance for fine co-focus of segmented mirror. And the interference fringes are utilized to verify the detective precision of Shack–Hartmann. After the co-focus fine-tuning of the segmented mirror, the tilt/tip residual surface error is better than 0.01λ RMS; the defocus residual surface error is better than 0.01λ RMS.展开更多
Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain.By varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may b...Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain.By varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may be controlled.This approach is used to tune the astigmatism of the tunable lenses,and it is shown that the generated wavefront may be accurately controlled.The lens presented here has an initial focal length of 32.6 mm and a tuning range of 12.3 mm for approximately 10%applied strain.The range of directly tunable Zernike polynomials representing astigmatism is about 3 mm,while the secondary lens errors,which cannot be tuned directly,vary only by about 0.2 mm.展开更多
基金supported by the National High Technology Research and Development Program of China
文摘In this paper, an active optics and co-focus experimental system of segmented mirror is built. Firstly, a support structure of segmented mirror is designed and it is verified by simulation to meet the requirement for the experimental system of segmented mirror. In this system, the large de-focus and tilt/tip errors of the segmented mirror are adjusted by observing the density and contrast of interference fringes based on isoclinic interference theory until the defocus and tilt/tip errors are in the detective range of the Shack–Hartmann. Then, the Shack–Hartmann is used to measure them and they are adjusted by actuators. The actuators are controlled by active optics to realize the closed-loop adjustment and maintenance for fine co-focus of segmented mirror. And the interference fringes are utilized to verify the detective precision of Shack–Hartmann. After the co-focus fine-tuning of the segmented mirror, the tilt/tip residual surface error is better than 0.01λ RMS; the defocus residual surface error is better than 0.01λ RMS.
基金This work was funded by the German Science Foundation within the framework of the Priority Program 1337 Aktive MikrooptikThe authors thank Philipp Muller and the Laboratory for Biomedical Technology at IMTEK for coating the master lenses.
文摘Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain.By varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may be controlled.This approach is used to tune the astigmatism of the tunable lenses,and it is shown that the generated wavefront may be accurately controlled.The lens presented here has an initial focal length of 32.6 mm and a tuning range of 12.3 mm for approximately 10%applied strain.The range of directly tunable Zernike polynomials representing astigmatism is about 3 mm,while the secondary lens errors,which cannot be tuned directly,vary only by about 0.2 mm.
