Alignment sensing and correcting assembly for an optical element

Claim 1

In an optical system comprising: a. a base structure; b. at least two optical elements; and c. a plurality of displacement actuators for positioning at least one of the optical elements to the base structure in accordance with a known displacement matrix [D], so that the optical elements define a first curvature profile; an assembly comprising: (1) a plurality of sensing means (a) positioned in accordance with a known position matrix [P] which is calculated based upon the Position of each of the sensing means with respect to each of the optical elements; the sensing means (b) sensing changes in the first curvature profile, due to arbitrary inputs to the optical system; and providing a corresponding plurality of sensing output signals [S]; and (2) a computation means for: (a) inputting the plurality of sensing output signals [S]; (b) inputting the position [P] and displacement matrices [D]; and (c) computing, on the basis of the sensing output signals [S], and the position [P] and displacement [D] matrices, at least one displacement actuator command [C], whereby, a realization of displacement actuator re-positioning, in accordance with the or each displacement actuator command [C], restores the system first curvature profile.