A new type of wavefront sensor for adaptive optics with pulsed laser beacons

摘要利用瑞利信标探测大气波前畸变是一种非常新颖的方法。 发射100纳秒紫外脉冲的近衍射极限激光器将在光波前相位扰动大气介质内投射出瞬时体积为30米长× 10厘米宽的近圆柱形的光柱。 湍流大气的一部分被100纳秒的脉冲及时冻结。瑞利辐射将背向散射光的相位信息特征量送入望远镜。 该场景信息将用于创建湍流的3-D特征的实时体积层析成像图。 来自该体积相位图的信号将驱动多平面自适应光学系统来校正宽等晕斑上的大气湍流。系统设计和有限的硬件原型将被设计，建造和测试，以验证理论。 这一创新思想的一个重要方面是如何做波前精度和分辨率的理论预期可以实现天文望远镜，如6.5米MMT。

Lloyd-HartAST9987358AbstractA very innovative approach to sense an atmospheric wavefront distortion with Rayleigh beacons is being developed. A near diffraction-limited laser emitting ultra-violet pulses of 100 nanoseconds will project columns of light whose instantaneous volume is a near cylindrical shape 30 meters long by 10 centimeters wide within the optical wavefront-phase perturbing atmospheric medium. A portion of the turbulent atmosphere is frozen in time by the 100 nanosecond pulse. Radiation will Rayleigh backscatter optical phase information characteristic of that volume into the telescope. This scene information will be used to create a real-time volumetric tomographic map of the 3-D character of the turbulence. Signals from this volume phase map will drive a multiple-plane Adaptive-Optics system to correct for atmospheric turbulence over a wide isoplanatic patch. Systems design and limited hardware prototypes will be designed built and tested to verify theory. An important aspect of this innovative idea is how well do the theoretical expectations for wavefront accuracy and resolution can be realized on an astronomical telescope such as the 6.5-meter MMT.