HARTMANN-TYPE OPTICAL WAVEFRONT SENSOR

摘要

An optical wavefront sensor for measuring phase tilt in two dimensions across the cross section of a beam (14), using only a single lenslet array (26) and a single camera sensor array (28). The rectangular lenslet array (26) is oriented at 45 d egrees to first and second orthogonal sets of axes defining multiple points of interest (22') in the beam cross section, such that each lenslet subaperture is centered (at 40) between ad jacent points of interest on the first and second axes. The points of interest (22') are locat ions corresponding to the positions of actuators (22) in an adaptive optics system. T he camera sensor array (28) has more cells per unit area than there are subapertures per u nit area. Only selected cells are activated, to provide for measurements at the approximat e midpoints of lines between adjacent points of interest (22') on the first and se cond orthogonal axes. Thus the sensor array (28) has enough active cells to effect measurements in both orthogonal directions without interference between the cells used for measuremen t in the two directions, and without the need for multiple lenslet arrays or sensor array s.